diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /mm/damon | |
parent | Initial commit. (diff) | |
download | linux-upstream/6.1.76.tar.xz linux-upstream/6.1.76.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'mm/damon')
-rw-r--r-- | mm/damon/Kconfig | 106 | ||||
-rw-r--r-- | mm/damon/Makefile | 9 | ||||
-rw-r--r-- | mm/damon/core-test.h | 313 | ||||
-rw-r--r-- | mm/damon/core.c | 1310 | ||||
-rw-r--r-- | mm/damon/dbgfs-test.h | 163 | ||||
-rw-r--r-- | mm/damon/dbgfs.c | 1114 | ||||
-rw-r--r-- | mm/damon/lru_sort.c | 340 | ||||
-rw-r--r-- | mm/damon/modules-common.h | 46 | ||||
-rw-r--r-- | mm/damon/ops-common.c | 135 | ||||
-rw-r--r-- | mm/damon/ops-common.h | 18 | ||||
-rw-r--r-- | mm/damon/paddr.c | 319 | ||||
-rw-r--r-- | mm/damon/reclaim.c | 284 | ||||
-rw-r--r-- | mm/damon/sysfs.c | 2909 | ||||
-rw-r--r-- | mm/damon/vaddr-test.h | 316 | ||||
-rw-r--r-- | mm/damon/vaddr.c | 715 |
15 files changed, 8097 insertions, 0 deletions
diff --git a/mm/damon/Kconfig b/mm/damon/Kconfig new file mode 100644 index 000000000..7821fcb3f --- /dev/null +++ b/mm/damon/Kconfig @@ -0,0 +1,106 @@ +# SPDX-License-Identifier: GPL-2.0-only + +menu "Data Access Monitoring" + +config DAMON + bool "DAMON: Data Access Monitoring Framework" + help + This builds a framework that allows kernel subsystems to monitor + access frequency of each memory region. The information can be useful + for performance-centric DRAM level memory management. + + See https://damonitor.github.io/doc/html/latest-damon/index.html for + more information. + +config DAMON_KUNIT_TEST + bool "Test for damon" if !KUNIT_ALL_TESTS + depends on DAMON && KUNIT=y + default KUNIT_ALL_TESTS + help + This builds the DAMON Kunit test suite. + + For more information on KUnit and unit tests in general, please refer + to the KUnit documentation. + + If unsure, say N. + +config DAMON_VADDR + bool "Data access monitoring operations for virtual address spaces" + depends on DAMON && MMU + select PAGE_IDLE_FLAG + help + This builds the default data access monitoring operations for DAMON + that work for virtual address spaces. + +config DAMON_PADDR + bool "Data access monitoring operations for the physical address space" + depends on DAMON && MMU + select PAGE_IDLE_FLAG + help + This builds the default data access monitoring operations for DAMON + that works for the physical address space. + +config DAMON_VADDR_KUNIT_TEST + bool "Test for DAMON operations" if !KUNIT_ALL_TESTS + depends on DAMON_VADDR && KUNIT=y + default KUNIT_ALL_TESTS + help + This builds the DAMON virtual addresses operations Kunit test suite. + + For more information on KUnit and unit tests in general, please refer + to the KUnit documentation. + + If unsure, say N. + +config DAMON_SYSFS + bool "DAMON sysfs interface" + depends on DAMON && SYSFS + help + This builds the sysfs interface for DAMON. The user space can use + the interface for arbitrary data access monitoring. + +config DAMON_DBGFS + bool "DAMON debugfs interface" + depends on DAMON_VADDR && DAMON_PADDR && DEBUG_FS + help + This builds the debugfs interface for DAMON. The user space admins + can use the interface for arbitrary data access monitoring. + + If unsure, say N. + + This will be removed after >5.15.y LTS kernel is released, so users + should move to the sysfs interface (DAMON_SYSFS). + +config DAMON_DBGFS_KUNIT_TEST + bool "Test for damon debugfs interface" if !KUNIT_ALL_TESTS + depends on DAMON_DBGFS && KUNIT=y + default KUNIT_ALL_TESTS + help + This builds the DAMON debugfs interface Kunit test suite. + + For more information on KUnit and unit tests in general, please refer + to the KUnit documentation. + + If unsure, say N. + +config DAMON_RECLAIM + bool "Build DAMON-based reclaim (DAMON_RECLAIM)" + depends on DAMON_PADDR + help + This builds the DAMON-based reclamation subsystem. It finds pages + that not accessed for a long time (cold) using DAMON and reclaim + those. + + This is suggested to be used as a proactive and lightweight + reclamation under light memory pressure, while the traditional page + scanning-based reclamation is used for heavy pressure. + +config DAMON_LRU_SORT + bool "Build DAMON-based LRU-lists sorting (DAMON_LRU_SORT)" + depends on DAMON_PADDR + help + This builds the DAMON-based LRU-lists sorting subsystem. It tries to + protect frequently accessed (hot) pages while rarely accessed (cold) + pages reclaimed first under memory pressure. + +endmenu diff --git a/mm/damon/Makefile b/mm/damon/Makefile new file mode 100644 index 000000000..3e6b8ad73 --- /dev/null +++ b/mm/damon/Makefile @@ -0,0 +1,9 @@ +# SPDX-License-Identifier: GPL-2.0 + +obj-y := core.o +obj-$(CONFIG_DAMON_VADDR) += ops-common.o vaddr.o +obj-$(CONFIG_DAMON_PADDR) += ops-common.o paddr.o +obj-$(CONFIG_DAMON_SYSFS) += sysfs.o +obj-$(CONFIG_DAMON_DBGFS) += dbgfs.o +obj-$(CONFIG_DAMON_RECLAIM) += reclaim.o +obj-$(CONFIG_DAMON_LRU_SORT) += lru_sort.o diff --git a/mm/damon/core-test.h b/mm/damon/core-test.h new file mode 100644 index 000000000..3db9b7368 --- /dev/null +++ b/mm/damon/core-test.h @@ -0,0 +1,313 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Data Access Monitor Unit Tests + * + * Copyright 2019 Amazon.com, Inc. or its affiliates. All rights reserved. + * + * Author: SeongJae Park <sjpark@amazon.de> + */ + +#ifdef CONFIG_DAMON_KUNIT_TEST + +#ifndef _DAMON_CORE_TEST_H +#define _DAMON_CORE_TEST_H + +#include <kunit/test.h> + +static void damon_test_regions(struct kunit *test) +{ + struct damon_region *r; + struct damon_target *t; + + r = damon_new_region(1, 2); + KUNIT_EXPECT_EQ(test, 1ul, r->ar.start); + KUNIT_EXPECT_EQ(test, 2ul, r->ar.end); + KUNIT_EXPECT_EQ(test, 0u, r->nr_accesses); + + t = damon_new_target(); + KUNIT_EXPECT_EQ(test, 0u, damon_nr_regions(t)); + + damon_add_region(r, t); + KUNIT_EXPECT_EQ(test, 1u, damon_nr_regions(t)); + + damon_del_region(r, t); + KUNIT_EXPECT_EQ(test, 0u, damon_nr_regions(t)); + + damon_free_target(t); +} + +static unsigned int nr_damon_targets(struct damon_ctx *ctx) +{ + struct damon_target *t; + unsigned int nr_targets = 0; + + damon_for_each_target(t, ctx) + nr_targets++; + + return nr_targets; +} + +static void damon_test_target(struct kunit *test) +{ + struct damon_ctx *c = damon_new_ctx(); + struct damon_target *t; + + t = damon_new_target(); + KUNIT_EXPECT_EQ(test, 0u, nr_damon_targets(c)); + + damon_add_target(c, t); + KUNIT_EXPECT_EQ(test, 1u, nr_damon_targets(c)); + + damon_destroy_target(t); + KUNIT_EXPECT_EQ(test, 0u, nr_damon_targets(c)); + + damon_destroy_ctx(c); +} + +/* + * Test kdamond_reset_aggregated() + * + * DAMON checks access to each region and aggregates this information as the + * access frequency of each region. In detail, it increases '->nr_accesses' of + * regions that an access has confirmed. 'kdamond_reset_aggregated()' flushes + * the aggregated information ('->nr_accesses' of each regions) to the result + * buffer. As a result of the flushing, the '->nr_accesses' of regions are + * initialized to zero. + */ +static void damon_test_aggregate(struct kunit *test) +{ + struct damon_ctx *ctx = damon_new_ctx(); + unsigned long saddr[][3] = {{10, 20, 30}, {5, 42, 49}, {13, 33, 55} }; + unsigned long eaddr[][3] = {{15, 27, 40}, {31, 45, 55}, {23, 44, 66} }; + unsigned long accesses[][3] = {{42, 95, 84}, {10, 20, 30}, {0, 1, 2} }; + struct damon_target *t; + struct damon_region *r; + int it, ir; + + for (it = 0; it < 3; it++) { + t = damon_new_target(); + damon_add_target(ctx, t); + } + + it = 0; + damon_for_each_target(t, ctx) { + for (ir = 0; ir < 3; ir++) { + r = damon_new_region(saddr[it][ir], eaddr[it][ir]); + r->nr_accesses = accesses[it][ir]; + damon_add_region(r, t); + } + it++; + } + kdamond_reset_aggregated(ctx); + it = 0; + damon_for_each_target(t, ctx) { + ir = 0; + /* '->nr_accesses' should be zeroed */ + damon_for_each_region(r, t) { + KUNIT_EXPECT_EQ(test, 0u, r->nr_accesses); + ir++; + } + /* regions should be preserved */ + KUNIT_EXPECT_EQ(test, 3, ir); + it++; + } + /* targets also should be preserved */ + KUNIT_EXPECT_EQ(test, 3, it); + + damon_destroy_ctx(ctx); +} + +static void damon_test_split_at(struct kunit *test) +{ + struct damon_ctx *c = damon_new_ctx(); + struct damon_target *t; + struct damon_region *r; + + t = damon_new_target(); + r = damon_new_region(0, 100); + damon_add_region(r, t); + damon_split_region_at(t, r, 25); + KUNIT_EXPECT_EQ(test, r->ar.start, 0ul); + KUNIT_EXPECT_EQ(test, r->ar.end, 25ul); + + r = damon_next_region(r); + KUNIT_EXPECT_EQ(test, r->ar.start, 25ul); + KUNIT_EXPECT_EQ(test, r->ar.end, 100ul); + + damon_free_target(t); + damon_destroy_ctx(c); +} + +static void damon_test_merge_two(struct kunit *test) +{ + struct damon_target *t; + struct damon_region *r, *r2, *r3; + int i; + + t = damon_new_target(); + r = damon_new_region(0, 100); + r->nr_accesses = 10; + damon_add_region(r, t); + r2 = damon_new_region(100, 300); + r2->nr_accesses = 20; + damon_add_region(r2, t); + + damon_merge_two_regions(t, r, r2); + KUNIT_EXPECT_EQ(test, r->ar.start, 0ul); + KUNIT_EXPECT_EQ(test, r->ar.end, 300ul); + KUNIT_EXPECT_EQ(test, r->nr_accesses, 16u); + + i = 0; + damon_for_each_region(r3, t) { + KUNIT_EXPECT_PTR_EQ(test, r, r3); + i++; + } + KUNIT_EXPECT_EQ(test, i, 1); + + damon_free_target(t); +} + +static struct damon_region *__nth_region_of(struct damon_target *t, int idx) +{ + struct damon_region *r; + unsigned int i = 0; + + damon_for_each_region(r, t) { + if (i++ == idx) + return r; + } + + return NULL; +} + +static void damon_test_merge_regions_of(struct kunit *test) +{ + struct damon_target *t; + struct damon_region *r; + unsigned long sa[] = {0, 100, 114, 122, 130, 156, 170, 184}; + unsigned long ea[] = {100, 112, 122, 130, 156, 170, 184, 230}; + unsigned int nrs[] = {0, 0, 10, 10, 20, 30, 1, 2}; + + unsigned long saddrs[] = {0, 114, 130, 156, 170}; + unsigned long eaddrs[] = {112, 130, 156, 170, 230}; + int i; + + t = damon_new_target(); + for (i = 0; i < ARRAY_SIZE(sa); i++) { + r = damon_new_region(sa[i], ea[i]); + r->nr_accesses = nrs[i]; + damon_add_region(r, t); + } + + damon_merge_regions_of(t, 9, 9999); + /* 0-112, 114-130, 130-156, 156-170 */ + KUNIT_EXPECT_EQ(test, damon_nr_regions(t), 5u); + for (i = 0; i < 5; i++) { + r = __nth_region_of(t, i); + KUNIT_EXPECT_EQ(test, r->ar.start, saddrs[i]); + KUNIT_EXPECT_EQ(test, r->ar.end, eaddrs[i]); + } + damon_free_target(t); +} + +static void damon_test_split_regions_of(struct kunit *test) +{ + struct damon_ctx *c = damon_new_ctx(); + struct damon_target *t; + struct damon_region *r; + + t = damon_new_target(); + r = damon_new_region(0, 22); + damon_add_region(r, t); + damon_split_regions_of(t, 2); + KUNIT_EXPECT_LE(test, damon_nr_regions(t), 2u); + damon_free_target(t); + + t = damon_new_target(); + r = damon_new_region(0, 220); + damon_add_region(r, t); + damon_split_regions_of(t, 4); + KUNIT_EXPECT_LE(test, damon_nr_regions(t), 4u); + damon_free_target(t); + damon_destroy_ctx(c); +} + +static void damon_test_ops_registration(struct kunit *test) +{ + struct damon_ctx *c = damon_new_ctx(); + struct damon_operations ops, bak; + + /* DAMON_OPS_{V,P}ADDR are registered on subsys_initcall */ + KUNIT_EXPECT_EQ(test, damon_select_ops(c, DAMON_OPS_VADDR), 0); + KUNIT_EXPECT_EQ(test, damon_select_ops(c, DAMON_OPS_PADDR), 0); + + /* Double-registration is prohibited */ + ops.id = DAMON_OPS_VADDR; + KUNIT_EXPECT_EQ(test, damon_register_ops(&ops), -EINVAL); + ops.id = DAMON_OPS_PADDR; + KUNIT_EXPECT_EQ(test, damon_register_ops(&ops), -EINVAL); + + /* Unknown ops id cannot be registered */ + KUNIT_EXPECT_EQ(test, damon_select_ops(c, NR_DAMON_OPS), -EINVAL); + + /* Registration should success after unregistration */ + mutex_lock(&damon_ops_lock); + bak = damon_registered_ops[DAMON_OPS_VADDR]; + damon_registered_ops[DAMON_OPS_VADDR] = (struct damon_operations){}; + mutex_unlock(&damon_ops_lock); + + ops.id = DAMON_OPS_VADDR; + KUNIT_EXPECT_EQ(test, damon_register_ops(&ops), 0); + + mutex_lock(&damon_ops_lock); + damon_registered_ops[DAMON_OPS_VADDR] = bak; + mutex_unlock(&damon_ops_lock); + + /* Check double-registration failure again */ + KUNIT_EXPECT_EQ(test, damon_register_ops(&ops), -EINVAL); +} + +static void damon_test_set_regions(struct kunit *test) +{ + struct damon_target *t = damon_new_target(); + struct damon_region *r1 = damon_new_region(4, 16); + struct damon_region *r2 = damon_new_region(24, 32); + struct damon_addr_range range = {.start = 8, .end = 28}; + unsigned long expects[] = {8, 16, 16, 24, 24, 28}; + int expect_idx = 0; + struct damon_region *r; + + damon_add_region(r1, t); + damon_add_region(r2, t); + damon_set_regions(t, &range, 1); + + KUNIT_EXPECT_EQ(test, damon_nr_regions(t), 3); + damon_for_each_region(r, t) { + KUNIT_EXPECT_EQ(test, r->ar.start, expects[expect_idx++]); + KUNIT_EXPECT_EQ(test, r->ar.end, expects[expect_idx++]); + } + damon_destroy_target(t); +} + +static struct kunit_case damon_test_cases[] = { + KUNIT_CASE(damon_test_target), + KUNIT_CASE(damon_test_regions), + KUNIT_CASE(damon_test_aggregate), + KUNIT_CASE(damon_test_split_at), + KUNIT_CASE(damon_test_merge_two), + KUNIT_CASE(damon_test_merge_regions_of), + KUNIT_CASE(damon_test_split_regions_of), + KUNIT_CASE(damon_test_ops_registration), + KUNIT_CASE(damon_test_set_regions), + {}, +}; + +static struct kunit_suite damon_test_suite = { + .name = "damon", + .test_cases = damon_test_cases, +}; +kunit_test_suite(damon_test_suite); + +#endif /* _DAMON_CORE_TEST_H */ + +#endif /* CONFIG_DAMON_KUNIT_TEST */ diff --git a/mm/damon/core.c b/mm/damon/core.c new file mode 100644 index 000000000..5db9bec8a --- /dev/null +++ b/mm/damon/core.c @@ -0,0 +1,1310 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Data Access Monitor + * + * Author: SeongJae Park <sjpark@amazon.de> + */ + +#define pr_fmt(fmt) "damon: " fmt + +#include <linux/damon.h> +#include <linux/delay.h> +#include <linux/kthread.h> +#include <linux/mm.h> +#include <linux/slab.h> +#include <linux/string.h> + +#define CREATE_TRACE_POINTS +#include <trace/events/damon.h> + +#ifdef CONFIG_DAMON_KUNIT_TEST +#undef DAMON_MIN_REGION +#define DAMON_MIN_REGION 1 +#endif + +static DEFINE_MUTEX(damon_lock); +static int nr_running_ctxs; +static bool running_exclusive_ctxs; + +static DEFINE_MUTEX(damon_ops_lock); +static struct damon_operations damon_registered_ops[NR_DAMON_OPS]; + +static struct kmem_cache *damon_region_cache __ro_after_init; + +/* Should be called under damon_ops_lock with id smaller than NR_DAMON_OPS */ +static bool __damon_is_registered_ops(enum damon_ops_id id) +{ + struct damon_operations empty_ops = {}; + + if (!memcmp(&empty_ops, &damon_registered_ops[id], sizeof(empty_ops))) + return false; + return true; +} + +/** + * damon_is_registered_ops() - Check if a given damon_operations is registered. + * @id: Id of the damon_operations to check if registered. + * + * Return: true if the ops is set, false otherwise. + */ +bool damon_is_registered_ops(enum damon_ops_id id) +{ + bool registered; + + if (id >= NR_DAMON_OPS) + return false; + mutex_lock(&damon_ops_lock); + registered = __damon_is_registered_ops(id); + mutex_unlock(&damon_ops_lock); + return registered; +} + +/** + * damon_register_ops() - Register a monitoring operations set to DAMON. + * @ops: monitoring operations set to register. + * + * This function registers a monitoring operations set of valid &struct + * damon_operations->id so that others can find and use them later. + * + * Return: 0 on success, negative error code otherwise. + */ +int damon_register_ops(struct damon_operations *ops) +{ + int err = 0; + + if (ops->id >= NR_DAMON_OPS) + return -EINVAL; + mutex_lock(&damon_ops_lock); + /* Fail for already registered ops */ + if (__damon_is_registered_ops(ops->id)) { + err = -EINVAL; + goto out; + } + damon_registered_ops[ops->id] = *ops; +out: + mutex_unlock(&damon_ops_lock); + return err; +} + +/** + * damon_select_ops() - Select a monitoring operations to use with the context. + * @ctx: monitoring context to use the operations. + * @id: id of the registered monitoring operations to select. + * + * This function finds registered monitoring operations set of @id and make + * @ctx to use it. + * + * Return: 0 on success, negative error code otherwise. + */ +int damon_select_ops(struct damon_ctx *ctx, enum damon_ops_id id) +{ + int err = 0; + + if (id >= NR_DAMON_OPS) + return -EINVAL; + + mutex_lock(&damon_ops_lock); + if (!__damon_is_registered_ops(id)) + err = -EINVAL; + else + ctx->ops = damon_registered_ops[id]; + mutex_unlock(&damon_ops_lock); + return err; +} + +/* + * Construct a damon_region struct + * + * Returns the pointer to the new struct if success, or NULL otherwise + */ +struct damon_region *damon_new_region(unsigned long start, unsigned long end) +{ + struct damon_region *region; + + region = kmem_cache_alloc(damon_region_cache, GFP_KERNEL); + if (!region) + return NULL; + + region->ar.start = start; + region->ar.end = end; + region->nr_accesses = 0; + INIT_LIST_HEAD(®ion->list); + + region->age = 0; + region->last_nr_accesses = 0; + + return region; +} + +void damon_add_region(struct damon_region *r, struct damon_target *t) +{ + list_add_tail(&r->list, &t->regions_list); + t->nr_regions++; +} + +static void damon_del_region(struct damon_region *r, struct damon_target *t) +{ + list_del(&r->list); + t->nr_regions--; +} + +static void damon_free_region(struct damon_region *r) +{ + kmem_cache_free(damon_region_cache, r); +} + +void damon_destroy_region(struct damon_region *r, struct damon_target *t) +{ + damon_del_region(r, t); + damon_free_region(r); +} + +/* + * Check whether a region is intersecting an address range + * + * Returns true if it is. + */ +static bool damon_intersect(struct damon_region *r, + struct damon_addr_range *re) +{ + return !(r->ar.end <= re->start || re->end <= r->ar.start); +} + +/* + * Fill holes in regions with new regions. + */ +static int damon_fill_regions_holes(struct damon_region *first, + struct damon_region *last, struct damon_target *t) +{ + struct damon_region *r = first; + + damon_for_each_region_from(r, t) { + struct damon_region *next, *newr; + + if (r == last) + break; + next = damon_next_region(r); + if (r->ar.end != next->ar.start) { + newr = damon_new_region(r->ar.end, next->ar.start); + if (!newr) + return -ENOMEM; + damon_insert_region(newr, r, next, t); + } + } + return 0; +} + +/* + * damon_set_regions() - Set regions of a target for given address ranges. + * @t: the given target. + * @ranges: array of new monitoring target ranges. + * @nr_ranges: length of @ranges. + * + * This function adds new regions to, or modify existing regions of a + * monitoring target to fit in specific ranges. + * + * Return: 0 if success, or negative error code otherwise. + */ +int damon_set_regions(struct damon_target *t, struct damon_addr_range *ranges, + unsigned int nr_ranges) +{ + struct damon_region *r, *next; + unsigned int i; + int err; + + /* Remove regions which are not in the new ranges */ + damon_for_each_region_safe(r, next, t) { + for (i = 0; i < nr_ranges; i++) { + if (damon_intersect(r, &ranges[i])) + break; + } + if (i == nr_ranges) + damon_destroy_region(r, t); + } + + r = damon_first_region(t); + /* Add new regions or resize existing regions to fit in the ranges */ + for (i = 0; i < nr_ranges; i++) { + struct damon_region *first = NULL, *last, *newr; + struct damon_addr_range *range; + + range = &ranges[i]; + /* Get the first/last regions intersecting with the range */ + damon_for_each_region_from(r, t) { + if (damon_intersect(r, range)) { + if (!first) + first = r; + last = r; + } + if (r->ar.start >= range->end) + break; + } + if (!first) { + /* no region intersects with this range */ + newr = damon_new_region( + ALIGN_DOWN(range->start, + DAMON_MIN_REGION), + ALIGN(range->end, DAMON_MIN_REGION)); + if (!newr) + return -ENOMEM; + damon_insert_region(newr, damon_prev_region(r), r, t); + } else { + /* resize intersecting regions to fit in this range */ + first->ar.start = ALIGN_DOWN(range->start, + DAMON_MIN_REGION); + last->ar.end = ALIGN(range->end, DAMON_MIN_REGION); + + /* fill possible holes in the range */ + err = damon_fill_regions_holes(first, last, t); + if (err) + return err; + } + } + return 0; +} + +/* initialize private fields of damos_quota and return the pointer */ +static struct damos_quota *damos_quota_init_priv(struct damos_quota *quota) +{ + quota->total_charged_sz = 0; + quota->total_charged_ns = 0; + quota->esz = 0; + quota->charged_sz = 0; + quota->charged_from = 0; + quota->charge_target_from = NULL; + quota->charge_addr_from = 0; + return quota; +} + +struct damos *damon_new_scheme(struct damos_access_pattern *pattern, + enum damos_action action, struct damos_quota *quota, + struct damos_watermarks *wmarks) +{ + struct damos *scheme; + + scheme = kmalloc(sizeof(*scheme), GFP_KERNEL); + if (!scheme) + return NULL; + scheme->pattern = *pattern; + scheme->action = action; + scheme->stat = (struct damos_stat){}; + INIT_LIST_HEAD(&scheme->list); + + scheme->quota = *(damos_quota_init_priv(quota)); + + scheme->wmarks = *wmarks; + scheme->wmarks.activated = true; + + return scheme; +} + +void damon_add_scheme(struct damon_ctx *ctx, struct damos *s) +{ + list_add_tail(&s->list, &ctx->schemes); +} + +static void damon_del_scheme(struct damos *s) +{ + list_del(&s->list); +} + +static void damon_free_scheme(struct damos *s) +{ + kfree(s); +} + +void damon_destroy_scheme(struct damos *s) +{ + damon_del_scheme(s); + damon_free_scheme(s); +} + +/* + * Construct a damon_target struct + * + * Returns the pointer to the new struct if success, or NULL otherwise + */ +struct damon_target *damon_new_target(void) +{ + struct damon_target *t; + + t = kmalloc(sizeof(*t), GFP_KERNEL); + if (!t) + return NULL; + + t->pid = NULL; + t->nr_regions = 0; + INIT_LIST_HEAD(&t->regions_list); + INIT_LIST_HEAD(&t->list); + + return t; +} + +void damon_add_target(struct damon_ctx *ctx, struct damon_target *t) +{ + list_add_tail(&t->list, &ctx->adaptive_targets); +} + +bool damon_targets_empty(struct damon_ctx *ctx) +{ + return list_empty(&ctx->adaptive_targets); +} + +static void damon_del_target(struct damon_target *t) +{ + list_del(&t->list); +} + +void damon_free_target(struct damon_target *t) +{ + struct damon_region *r, *next; + + damon_for_each_region_safe(r, next, t) + damon_free_region(r); + kfree(t); +} + +void damon_destroy_target(struct damon_target *t) +{ + damon_del_target(t); + damon_free_target(t); +} + +unsigned int damon_nr_regions(struct damon_target *t) +{ + return t->nr_regions; +} + +struct damon_ctx *damon_new_ctx(void) +{ + struct damon_ctx *ctx; + + ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); + if (!ctx) + return NULL; + + init_completion(&ctx->kdamond_started); + + ctx->attrs.sample_interval = 5 * 1000; + ctx->attrs.aggr_interval = 100 * 1000; + ctx->attrs.ops_update_interval = 60 * 1000 * 1000; + + ktime_get_coarse_ts64(&ctx->last_aggregation); + ctx->last_ops_update = ctx->last_aggregation; + + mutex_init(&ctx->kdamond_lock); + + ctx->attrs.min_nr_regions = 10; + ctx->attrs.max_nr_regions = 1000; + + INIT_LIST_HEAD(&ctx->adaptive_targets); + INIT_LIST_HEAD(&ctx->schemes); + + return ctx; +} + +static void damon_destroy_targets(struct damon_ctx *ctx) +{ + struct damon_target *t, *next_t; + + if (ctx->ops.cleanup) { + ctx->ops.cleanup(ctx); + return; + } + + damon_for_each_target_safe(t, next_t, ctx) + damon_destroy_target(t); +} + +void damon_destroy_ctx(struct damon_ctx *ctx) +{ + struct damos *s, *next_s; + + damon_destroy_targets(ctx); + + damon_for_each_scheme_safe(s, next_s, ctx) + damon_destroy_scheme(s); + + kfree(ctx); +} + +/** + * damon_set_attrs() - Set attributes for the monitoring. + * @ctx: monitoring context + * @attrs: monitoring attributes + * + * This function should not be called while the kdamond is running. + * Every time interval is in micro-seconds. + * + * Return: 0 on success, negative error code otherwise. + */ +int damon_set_attrs(struct damon_ctx *ctx, struct damon_attrs *attrs) +{ + if (attrs->min_nr_regions < 3) + return -EINVAL; + if (attrs->min_nr_regions > attrs->max_nr_regions) + return -EINVAL; + + ctx->attrs = *attrs; + return 0; +} + +/** + * damon_set_schemes() - Set data access monitoring based operation schemes. + * @ctx: monitoring context + * @schemes: array of the schemes + * @nr_schemes: number of entries in @schemes + * + * This function should not be called while the kdamond of the context is + * running. + */ +void damon_set_schemes(struct damon_ctx *ctx, struct damos **schemes, + ssize_t nr_schemes) +{ + struct damos *s, *next; + ssize_t i; + + damon_for_each_scheme_safe(s, next, ctx) + damon_destroy_scheme(s); + for (i = 0; i < nr_schemes; i++) + damon_add_scheme(ctx, schemes[i]); +} + +/** + * damon_nr_running_ctxs() - Return number of currently running contexts. + */ +int damon_nr_running_ctxs(void) +{ + int nr_ctxs; + + mutex_lock(&damon_lock); + nr_ctxs = nr_running_ctxs; + mutex_unlock(&damon_lock); + + return nr_ctxs; +} + +/* Returns the size upper limit for each monitoring region */ +static unsigned long damon_region_sz_limit(struct damon_ctx *ctx) +{ + struct damon_target *t; + struct damon_region *r; + unsigned long sz = 0; + + damon_for_each_target(t, ctx) { + damon_for_each_region(r, t) + sz += damon_sz_region(r); + } + + if (ctx->attrs.min_nr_regions) + sz /= ctx->attrs.min_nr_regions; + if (sz < DAMON_MIN_REGION) + sz = DAMON_MIN_REGION; + + return sz; +} + +static int kdamond_fn(void *data); + +/* + * __damon_start() - Starts monitoring with given context. + * @ctx: monitoring context + * + * This function should be called while damon_lock is hold. + * + * Return: 0 on success, negative error code otherwise. + */ +static int __damon_start(struct damon_ctx *ctx) +{ + int err = -EBUSY; + + mutex_lock(&ctx->kdamond_lock); + if (!ctx->kdamond) { + err = 0; + reinit_completion(&ctx->kdamond_started); + ctx->kdamond = kthread_run(kdamond_fn, ctx, "kdamond.%d", + nr_running_ctxs); + if (IS_ERR(ctx->kdamond)) { + err = PTR_ERR(ctx->kdamond); + ctx->kdamond = NULL; + } else { + wait_for_completion(&ctx->kdamond_started); + } + } + mutex_unlock(&ctx->kdamond_lock); + + return err; +} + +/** + * damon_start() - Starts the monitorings for a given group of contexts. + * @ctxs: an array of the pointers for contexts to start monitoring + * @nr_ctxs: size of @ctxs + * @exclusive: exclusiveness of this contexts group + * + * This function starts a group of monitoring threads for a group of monitoring + * contexts. One thread per each context is created and run in parallel. The + * caller should handle synchronization between the threads by itself. If + * @exclusive is true and a group of threads that created by other + * 'damon_start()' call is currently running, this function does nothing but + * returns -EBUSY. + * + * Return: 0 on success, negative error code otherwise. + */ +int damon_start(struct damon_ctx **ctxs, int nr_ctxs, bool exclusive) +{ + int i; + int err = 0; + + mutex_lock(&damon_lock); + if ((exclusive && nr_running_ctxs) || + (!exclusive && running_exclusive_ctxs)) { + mutex_unlock(&damon_lock); + return -EBUSY; + } + + for (i = 0; i < nr_ctxs; i++) { + err = __damon_start(ctxs[i]); + if (err) + break; + nr_running_ctxs++; + } + if (exclusive && nr_running_ctxs) + running_exclusive_ctxs = true; + mutex_unlock(&damon_lock); + + return err; +} + +/* + * __damon_stop() - Stops monitoring of a given context. + * @ctx: monitoring context + * + * Return: 0 on success, negative error code otherwise. + */ +static int __damon_stop(struct damon_ctx *ctx) +{ + struct task_struct *tsk; + + mutex_lock(&ctx->kdamond_lock); + tsk = ctx->kdamond; + if (tsk) { + get_task_struct(tsk); + mutex_unlock(&ctx->kdamond_lock); + kthread_stop(tsk); + put_task_struct(tsk); + return 0; + } + mutex_unlock(&ctx->kdamond_lock); + + return -EPERM; +} + +/** + * damon_stop() - Stops the monitorings for a given group of contexts. + * @ctxs: an array of the pointers for contexts to stop monitoring + * @nr_ctxs: size of @ctxs + * + * Return: 0 on success, negative error code otherwise. + */ +int damon_stop(struct damon_ctx **ctxs, int nr_ctxs) +{ + int i, err = 0; + + for (i = 0; i < nr_ctxs; i++) { + /* nr_running_ctxs is decremented in kdamond_fn */ + err = __damon_stop(ctxs[i]); + if (err) + break; + } + return err; +} + +/* + * damon_check_reset_time_interval() - Check if a time interval is elapsed. + * @baseline: the time to check whether the interval has elapsed since + * @interval: the time interval (microseconds) + * + * See whether the given time interval has passed since the given baseline + * time. If so, it also updates the baseline to current time for next check. + * + * Return: true if the time interval has passed, or false otherwise. + */ +static bool damon_check_reset_time_interval(struct timespec64 *baseline, + unsigned long interval) +{ + struct timespec64 now; + + ktime_get_coarse_ts64(&now); + if ((timespec64_to_ns(&now) - timespec64_to_ns(baseline)) < + interval * 1000) + return false; + *baseline = now; + return true; +} + +/* + * Check whether it is time to flush the aggregated information + */ +static bool kdamond_aggregate_interval_passed(struct damon_ctx *ctx) +{ + return damon_check_reset_time_interval(&ctx->last_aggregation, + ctx->attrs.aggr_interval); +} + +/* + * Reset the aggregated monitoring results ('nr_accesses' of each region). + */ +static void kdamond_reset_aggregated(struct damon_ctx *c) +{ + struct damon_target *t; + unsigned int ti = 0; /* target's index */ + + damon_for_each_target(t, c) { + struct damon_region *r; + + damon_for_each_region(r, t) { + trace_damon_aggregated(t, ti, r, damon_nr_regions(t)); + r->last_nr_accesses = r->nr_accesses; + r->nr_accesses = 0; + } + ti++; + } +} + +static void damon_split_region_at(struct damon_target *t, + struct damon_region *r, unsigned long sz_r); + +static bool __damos_valid_target(struct damon_region *r, struct damos *s) +{ + unsigned long sz; + + sz = damon_sz_region(r); + return s->pattern.min_sz_region <= sz && + sz <= s->pattern.max_sz_region && + s->pattern.min_nr_accesses <= r->nr_accesses && + r->nr_accesses <= s->pattern.max_nr_accesses && + s->pattern.min_age_region <= r->age && + r->age <= s->pattern.max_age_region; +} + +static bool damos_valid_target(struct damon_ctx *c, struct damon_target *t, + struct damon_region *r, struct damos *s) +{ + bool ret = __damos_valid_target(r, s); + + if (!ret || !s->quota.esz || !c->ops.get_scheme_score) + return ret; + + return c->ops.get_scheme_score(c, t, r, s) >= s->quota.min_score; +} + +static void damon_do_apply_schemes(struct damon_ctx *c, + struct damon_target *t, + struct damon_region *r) +{ + struct damos *s; + + damon_for_each_scheme(s, c) { + struct damos_quota *quota = &s->quota; + unsigned long sz = damon_sz_region(r); + struct timespec64 begin, end; + unsigned long sz_applied = 0; + + if (!s->wmarks.activated) + continue; + + /* Check the quota */ + if (quota->esz && quota->charged_sz >= quota->esz) + continue; + + /* Skip previously charged regions */ + if (quota->charge_target_from) { + if (t != quota->charge_target_from) + continue; + if (r == damon_last_region(t)) { + quota->charge_target_from = NULL; + quota->charge_addr_from = 0; + continue; + } + if (quota->charge_addr_from && + r->ar.end <= quota->charge_addr_from) + continue; + + if (quota->charge_addr_from && r->ar.start < + quota->charge_addr_from) { + sz = ALIGN_DOWN(quota->charge_addr_from - + r->ar.start, DAMON_MIN_REGION); + if (!sz) { + if (damon_sz_region(r) <= + DAMON_MIN_REGION) + continue; + sz = DAMON_MIN_REGION; + } + damon_split_region_at(t, r, sz); + r = damon_next_region(r); + sz = damon_sz_region(r); + } + quota->charge_target_from = NULL; + quota->charge_addr_from = 0; + } + + if (!damos_valid_target(c, t, r, s)) + continue; + + /* Apply the scheme */ + if (c->ops.apply_scheme) { + if (quota->esz && + quota->charged_sz + sz > quota->esz) { + sz = ALIGN_DOWN(quota->esz - quota->charged_sz, + DAMON_MIN_REGION); + if (!sz) + goto update_stat; + damon_split_region_at(t, r, sz); + } + ktime_get_coarse_ts64(&begin); + sz_applied = c->ops.apply_scheme(c, t, r, s); + ktime_get_coarse_ts64(&end); + quota->total_charged_ns += timespec64_to_ns(&end) - + timespec64_to_ns(&begin); + quota->charged_sz += sz; + if (quota->esz && quota->charged_sz >= quota->esz) { + quota->charge_target_from = t; + quota->charge_addr_from = r->ar.end + 1; + } + } + if (s->action != DAMOS_STAT) + r->age = 0; + +update_stat: + s->stat.nr_tried++; + s->stat.sz_tried += sz; + if (sz_applied) + s->stat.nr_applied++; + s->stat.sz_applied += sz_applied; + } +} + +/* Shouldn't be called if quota->ms and quota->sz are zero */ +static void damos_set_effective_quota(struct damos_quota *quota) +{ + unsigned long throughput; + unsigned long esz; + + if (!quota->ms) { + quota->esz = quota->sz; + return; + } + + if (quota->total_charged_ns) + throughput = quota->total_charged_sz * 1000000 / + quota->total_charged_ns; + else + throughput = PAGE_SIZE * 1024; + esz = throughput * quota->ms; + + if (quota->sz && quota->sz < esz) + esz = quota->sz; + quota->esz = esz; +} + +static void kdamond_apply_schemes(struct damon_ctx *c) +{ + struct damon_target *t; + struct damon_region *r, *next_r; + struct damos *s; + + damon_for_each_scheme(s, c) { + struct damos_quota *quota = &s->quota; + unsigned long cumulated_sz; + unsigned int score, max_score = 0; + + if (!s->wmarks.activated) + continue; + + if (!quota->ms && !quota->sz) + continue; + + /* New charge window starts */ + if (time_after_eq(jiffies, quota->charged_from + + msecs_to_jiffies( + quota->reset_interval))) { + if (quota->esz && quota->charged_sz >= quota->esz) + s->stat.qt_exceeds++; + quota->total_charged_sz += quota->charged_sz; + quota->charged_from = jiffies; + quota->charged_sz = 0; + damos_set_effective_quota(quota); + } + + if (!c->ops.get_scheme_score) + continue; + + /* Fill up the score histogram */ + memset(quota->histogram, 0, sizeof(quota->histogram)); + damon_for_each_target(t, c) { + damon_for_each_region(r, t) { + if (!__damos_valid_target(r, s)) + continue; + score = c->ops.get_scheme_score( + c, t, r, s); + quota->histogram[score] += damon_sz_region(r); + if (score > max_score) + max_score = score; + } + } + + /* Set the min score limit */ + for (cumulated_sz = 0, score = max_score; ; score--) { + cumulated_sz += quota->histogram[score]; + if (cumulated_sz >= quota->esz || !score) + break; + } + quota->min_score = score; + } + + damon_for_each_target(t, c) { + damon_for_each_region_safe(r, next_r, t) + damon_do_apply_schemes(c, t, r); + } +} + +/* + * Merge two adjacent regions into one region + */ +static void damon_merge_two_regions(struct damon_target *t, + struct damon_region *l, struct damon_region *r) +{ + unsigned long sz_l = damon_sz_region(l), sz_r = damon_sz_region(r); + + l->nr_accesses = (l->nr_accesses * sz_l + r->nr_accesses * sz_r) / + (sz_l + sz_r); + l->age = (l->age * sz_l + r->age * sz_r) / (sz_l + sz_r); + l->ar.end = r->ar.end; + damon_destroy_region(r, t); +} + +/* + * Merge adjacent regions having similar access frequencies + * + * t target affected by this merge operation + * thres '->nr_accesses' diff threshold for the merge + * sz_limit size upper limit of each region + */ +static void damon_merge_regions_of(struct damon_target *t, unsigned int thres, + unsigned long sz_limit) +{ + struct damon_region *r, *prev = NULL, *next; + + damon_for_each_region_safe(r, next, t) { + if (abs(r->nr_accesses - r->last_nr_accesses) > thres) + r->age = 0; + else + r->age++; + + if (prev && prev->ar.end == r->ar.start && + abs(prev->nr_accesses - r->nr_accesses) <= thres && + damon_sz_region(prev) + damon_sz_region(r) <= sz_limit) + damon_merge_two_regions(t, prev, r); + else + prev = r; + } +} + +/* + * Merge adjacent regions having similar access frequencies + * + * threshold '->nr_accesses' diff threshold for the merge + * sz_limit size upper limit of each region + * + * This function merges monitoring target regions which are adjacent and their + * access frequencies are similar. This is for minimizing the monitoring + * overhead under the dynamically changeable access pattern. If a merge was + * unnecessarily made, later 'kdamond_split_regions()' will revert it. + */ +static void kdamond_merge_regions(struct damon_ctx *c, unsigned int threshold, + unsigned long sz_limit) +{ + struct damon_target *t; + + damon_for_each_target(t, c) + damon_merge_regions_of(t, threshold, sz_limit); +} + +/* + * Split a region in two + * + * r the region to be split + * sz_r size of the first sub-region that will be made + */ +static void damon_split_region_at(struct damon_target *t, + struct damon_region *r, unsigned long sz_r) +{ + struct damon_region *new; + + new = damon_new_region(r->ar.start + sz_r, r->ar.end); + if (!new) + return; + + r->ar.end = new->ar.start; + + new->age = r->age; + new->last_nr_accesses = r->last_nr_accesses; + + damon_insert_region(new, r, damon_next_region(r), t); +} + +/* Split every region in the given target into 'nr_subs' regions */ +static void damon_split_regions_of(struct damon_target *t, int nr_subs) +{ + struct damon_region *r, *next; + unsigned long sz_region, sz_sub = 0; + int i; + + damon_for_each_region_safe(r, next, t) { + sz_region = damon_sz_region(r); + + for (i = 0; i < nr_subs - 1 && + sz_region > 2 * DAMON_MIN_REGION; i++) { + /* + * Randomly select size of left sub-region to be at + * least 10 percent and at most 90% of original region + */ + sz_sub = ALIGN_DOWN(damon_rand(1, 10) * + sz_region / 10, DAMON_MIN_REGION); + /* Do not allow blank region */ + if (sz_sub == 0 || sz_sub >= sz_region) + continue; + + damon_split_region_at(t, r, sz_sub); + sz_region = sz_sub; + } + } +} + +/* + * Split every target region into randomly-sized small regions + * + * This function splits every target region into random-sized small regions if + * current total number of the regions is equal or smaller than half of the + * user-specified maximum number of regions. This is for maximizing the + * monitoring accuracy under the dynamically changeable access patterns. If a + * split was unnecessarily made, later 'kdamond_merge_regions()' will revert + * it. + */ +static void kdamond_split_regions(struct damon_ctx *ctx) +{ + struct damon_target *t; + unsigned int nr_regions = 0; + static unsigned int last_nr_regions; + int nr_subregions = 2; + + damon_for_each_target(t, ctx) + nr_regions += damon_nr_regions(t); + + if (nr_regions > ctx->attrs.max_nr_regions / 2) + return; + + /* Maybe the middle of the region has different access frequency */ + if (last_nr_regions == nr_regions && + nr_regions < ctx->attrs.max_nr_regions / 3) + nr_subregions = 3; + + damon_for_each_target(t, ctx) + damon_split_regions_of(t, nr_subregions); + + last_nr_regions = nr_regions; +} + +/* + * Check whether it is time to check and apply the operations-related data + * structures. + * + * Returns true if it is. + */ +static bool kdamond_need_update_operations(struct damon_ctx *ctx) +{ + return damon_check_reset_time_interval(&ctx->last_ops_update, + ctx->attrs.ops_update_interval); +} + +/* + * Check whether current monitoring should be stopped + * + * The monitoring is stopped when either the user requested to stop, or all + * monitoring targets are invalid. + * + * Returns true if need to stop current monitoring. + */ +static bool kdamond_need_stop(struct damon_ctx *ctx) +{ + struct damon_target *t; + + if (kthread_should_stop()) + return true; + + if (!ctx->ops.target_valid) + return false; + + damon_for_each_target(t, ctx) { + if (ctx->ops.target_valid(t)) + return false; + } + + return true; +} + +static unsigned long damos_wmark_metric_value(enum damos_wmark_metric metric) +{ + struct sysinfo i; + + switch (metric) { + case DAMOS_WMARK_FREE_MEM_RATE: + si_meminfo(&i); + return i.freeram * 1000 / i.totalram; + default: + break; + } + return -EINVAL; +} + +/* + * Returns zero if the scheme is active. Else, returns time to wait for next + * watermark check in micro-seconds. + */ +static unsigned long damos_wmark_wait_us(struct damos *scheme) +{ + unsigned long metric; + + if (scheme->wmarks.metric == DAMOS_WMARK_NONE) + return 0; + + metric = damos_wmark_metric_value(scheme->wmarks.metric); + /* higher than high watermark or lower than low watermark */ + if (metric > scheme->wmarks.high || scheme->wmarks.low > metric) { + if (scheme->wmarks.activated) + pr_debug("deactivate a scheme (%d) for %s wmark\n", + scheme->action, + metric > scheme->wmarks.high ? + "high" : "low"); + scheme->wmarks.activated = false; + return scheme->wmarks.interval; + } + + /* inactive and higher than middle watermark */ + if ((scheme->wmarks.high >= metric && metric >= scheme->wmarks.mid) && + !scheme->wmarks.activated) + return scheme->wmarks.interval; + + if (!scheme->wmarks.activated) + pr_debug("activate a scheme (%d)\n", scheme->action); + scheme->wmarks.activated = true; + return 0; +} + +static void kdamond_usleep(unsigned long usecs) +{ + /* See Documentation/timers/timers-howto.rst for the thresholds */ + if (usecs > 20 * USEC_PER_MSEC) + schedule_timeout_idle(usecs_to_jiffies(usecs)); + else + usleep_idle_range(usecs, usecs + 1); +} + +/* Returns negative error code if it's not activated but should return */ +static int kdamond_wait_activation(struct damon_ctx *ctx) +{ + struct damos *s; + unsigned long wait_time; + unsigned long min_wait_time = 0; + bool init_wait_time = false; + + while (!kdamond_need_stop(ctx)) { + damon_for_each_scheme(s, ctx) { + wait_time = damos_wmark_wait_us(s); + if (!init_wait_time || wait_time < min_wait_time) { + init_wait_time = true; + min_wait_time = wait_time; + } + } + if (!min_wait_time) + return 0; + + kdamond_usleep(min_wait_time); + + if (ctx->callback.after_wmarks_check && + ctx->callback.after_wmarks_check(ctx)) + break; + } + return -EBUSY; +} + +/* + * The monitoring daemon that runs as a kernel thread + */ +static int kdamond_fn(void *data) +{ + struct damon_ctx *ctx = data; + struct damon_target *t; + struct damon_region *r, *next; + unsigned int max_nr_accesses = 0; + unsigned long sz_limit = 0; + + pr_debug("kdamond (%d) starts\n", current->pid); + + complete(&ctx->kdamond_started); + + if (ctx->ops.init) + ctx->ops.init(ctx); + if (ctx->callback.before_start && ctx->callback.before_start(ctx)) + goto done; + + sz_limit = damon_region_sz_limit(ctx); + + while (!kdamond_need_stop(ctx)) { + if (kdamond_wait_activation(ctx)) + break; + + if (ctx->ops.prepare_access_checks) + ctx->ops.prepare_access_checks(ctx); + if (ctx->callback.after_sampling && + ctx->callback.after_sampling(ctx)) + break; + + kdamond_usleep(ctx->attrs.sample_interval); + + if (ctx->ops.check_accesses) + max_nr_accesses = ctx->ops.check_accesses(ctx); + + if (kdamond_aggregate_interval_passed(ctx)) { + kdamond_merge_regions(ctx, + max_nr_accesses / 10, + sz_limit); + if (ctx->callback.after_aggregation && + ctx->callback.after_aggregation(ctx)) + break; + kdamond_apply_schemes(ctx); + kdamond_reset_aggregated(ctx); + kdamond_split_regions(ctx); + if (ctx->ops.reset_aggregated) + ctx->ops.reset_aggregated(ctx); + } + + if (kdamond_need_update_operations(ctx)) { + if (ctx->ops.update) + ctx->ops.update(ctx); + sz_limit = damon_region_sz_limit(ctx); + } + } +done: + damon_for_each_target(t, ctx) { + damon_for_each_region_safe(r, next, t) + damon_destroy_region(r, t); + } + + if (ctx->callback.before_terminate) + ctx->callback.before_terminate(ctx); + if (ctx->ops.cleanup) + ctx->ops.cleanup(ctx); + + pr_debug("kdamond (%d) finishes\n", current->pid); + mutex_lock(&ctx->kdamond_lock); + ctx->kdamond = NULL; + mutex_unlock(&ctx->kdamond_lock); + + mutex_lock(&damon_lock); + nr_running_ctxs--; + if (!nr_running_ctxs && running_exclusive_ctxs) + running_exclusive_ctxs = false; + mutex_unlock(&damon_lock); + + return 0; +} + +/* + * struct damon_system_ram_region - System RAM resource address region of + * [@start, @end). + * @start: Start address of the region (inclusive). + * @end: End address of the region (exclusive). + */ +struct damon_system_ram_region { + unsigned long start; + unsigned long end; +}; + +static int walk_system_ram(struct resource *res, void *arg) +{ + struct damon_system_ram_region *a = arg; + + if (a->end - a->start < resource_size(res)) { + a->start = res->start; + a->end = res->end; + } + return 0; +} + +/* + * Find biggest 'System RAM' resource and store its start and end address in + * @start and @end, respectively. If no System RAM is found, returns false. + */ +static bool damon_find_biggest_system_ram(unsigned long *start, + unsigned long *end) + +{ + struct damon_system_ram_region arg = {}; + + walk_system_ram_res(0, ULONG_MAX, &arg, walk_system_ram); + if (arg.end <= arg.start) + return false; + + *start = arg.start; + *end = arg.end; + return true; +} + +/** + * damon_set_region_biggest_system_ram_default() - Set the region of the given + * monitoring target as requested, or biggest 'System RAM'. + * @t: The monitoring target to set the region. + * @start: The pointer to the start address of the region. + * @end: The pointer to the end address of the region. + * + * This function sets the region of @t as requested by @start and @end. If the + * values of @start and @end are zero, however, this function finds the biggest + * 'System RAM' resource and sets the region to cover the resource. In the + * latter case, this function saves the start and end addresses of the resource + * in @start and @end, respectively. + * + * Return: 0 on success, negative error code otherwise. + */ +int damon_set_region_biggest_system_ram_default(struct damon_target *t, + unsigned long *start, unsigned long *end) +{ + struct damon_addr_range addr_range; + + if (*start > *end) + return -EINVAL; + + if (!*start && !*end && + !damon_find_biggest_system_ram(start, end)) + return -EINVAL; + + addr_range.start = *start; + addr_range.end = *end; + return damon_set_regions(t, &addr_range, 1); +} + +static int __init damon_init(void) +{ + damon_region_cache = KMEM_CACHE(damon_region, 0); + if (unlikely(!damon_region_cache)) { + pr_err("creating damon_region_cache fails\n"); + return -ENOMEM; + } + + return 0; +} + +subsys_initcall(damon_init); + +#include "core-test.h" diff --git a/mm/damon/dbgfs-test.h b/mm/damon/dbgfs-test.h new file mode 100644 index 000000000..0bb0d532b --- /dev/null +++ b/mm/damon/dbgfs-test.h @@ -0,0 +1,163 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * DAMON Debugfs Interface Unit Tests + * + * Author: SeongJae Park <sjpark@amazon.de> + */ + +#ifdef CONFIG_DAMON_DBGFS_KUNIT_TEST + +#ifndef _DAMON_DBGFS_TEST_H +#define _DAMON_DBGFS_TEST_H + +#include <kunit/test.h> + +static void damon_dbgfs_test_str_to_ints(struct kunit *test) +{ + char *question; + int *answers; + int expected[] = {12, 35, 46}; + ssize_t nr_integers = 0, i; + + question = "123"; + answers = str_to_ints(question, strlen(question), &nr_integers); + KUNIT_EXPECT_EQ(test, (ssize_t)1, nr_integers); + KUNIT_EXPECT_EQ(test, 123, answers[0]); + kfree(answers); + + question = "123abc"; + answers = str_to_ints(question, strlen(question), &nr_integers); + KUNIT_EXPECT_EQ(test, (ssize_t)1, nr_integers); + KUNIT_EXPECT_EQ(test, 123, answers[0]); + kfree(answers); + + question = "a123"; + answers = str_to_ints(question, strlen(question), &nr_integers); + KUNIT_EXPECT_EQ(test, (ssize_t)0, nr_integers); + kfree(answers); + + question = "12 35"; + answers = str_to_ints(question, strlen(question), &nr_integers); + KUNIT_EXPECT_EQ(test, (ssize_t)2, nr_integers); + for (i = 0; i < nr_integers; i++) + KUNIT_EXPECT_EQ(test, expected[i], answers[i]); + kfree(answers); + + question = "12 35 46"; + answers = str_to_ints(question, strlen(question), &nr_integers); + KUNIT_EXPECT_EQ(test, (ssize_t)3, nr_integers); + for (i = 0; i < nr_integers; i++) + KUNIT_EXPECT_EQ(test, expected[i], answers[i]); + kfree(answers); + + question = "12 35 abc 46"; + answers = str_to_ints(question, strlen(question), &nr_integers); + KUNIT_EXPECT_EQ(test, (ssize_t)2, nr_integers); + for (i = 0; i < 2; i++) + KUNIT_EXPECT_EQ(test, expected[i], answers[i]); + kfree(answers); + + question = ""; + answers = str_to_ints(question, strlen(question), &nr_integers); + KUNIT_EXPECT_EQ(test, (ssize_t)0, nr_integers); + kfree(answers); + + question = "\n"; + answers = str_to_ints(question, strlen(question), &nr_integers); + KUNIT_EXPECT_EQ(test, (ssize_t)0, nr_integers); + kfree(answers); +} + +static void damon_dbgfs_test_set_targets(struct kunit *test) +{ + struct damon_ctx *ctx = dbgfs_new_ctx(); + char buf[64]; + + /* Make DAMON consider target has no pid */ + damon_select_ops(ctx, DAMON_OPS_PADDR); + + dbgfs_set_targets(ctx, 0, NULL); + sprint_target_ids(ctx, buf, 64); + KUNIT_EXPECT_STREQ(test, (char *)buf, "\n"); + + dbgfs_set_targets(ctx, 1, NULL); + sprint_target_ids(ctx, buf, 64); + KUNIT_EXPECT_STREQ(test, (char *)buf, "42\n"); + + dbgfs_set_targets(ctx, 0, NULL); + sprint_target_ids(ctx, buf, 64); + KUNIT_EXPECT_STREQ(test, (char *)buf, "\n"); + + dbgfs_destroy_ctx(ctx); +} + +static void damon_dbgfs_test_set_init_regions(struct kunit *test) +{ + struct damon_ctx *ctx = damon_new_ctx(); + /* Each line represents one region in ``<target idx> <start> <end>`` */ + char * const valid_inputs[] = {"1 10 20\n 1 20 30\n1 35 45", + "1 10 20\n", + "1 10 20\n0 39 59\n0 70 134\n 1 20 25\n", + ""}; + /* Reading the file again will show sorted, clean output */ + char * const valid_expects[] = {"1 10 20\n1 20 30\n1 35 45\n", + "1 10 20\n", + "0 39 59\n0 70 134\n1 10 20\n1 20 25\n", + ""}; + char * const invalid_inputs[] = {"3 10 20\n", /* target not exists */ + "1 10 20\n 1 14 26\n", /* regions overlap */ + "0 10 20\n1 30 40\n 0 5 8"}; /* not sorted by address */ + char *input, *expect; + int i, rc; + char buf[256]; + + damon_select_ops(ctx, DAMON_OPS_PADDR); + + dbgfs_set_targets(ctx, 3, NULL); + + /* Put valid inputs and check the results */ + for (i = 0; i < ARRAY_SIZE(valid_inputs); i++) { + input = valid_inputs[i]; + expect = valid_expects[i]; + + rc = set_init_regions(ctx, input, strnlen(input, 256)); + KUNIT_EXPECT_EQ(test, rc, 0); + + memset(buf, 0, 256); + sprint_init_regions(ctx, buf, 256); + + KUNIT_EXPECT_STREQ(test, (char *)buf, expect); + } + /* Put invalid inputs and check the return error code */ + for (i = 0; i < ARRAY_SIZE(invalid_inputs); i++) { + input = invalid_inputs[i]; + pr_info("input: %s\n", input); + rc = set_init_regions(ctx, input, strnlen(input, 256)); + KUNIT_EXPECT_EQ(test, rc, -EINVAL); + + memset(buf, 0, 256); + sprint_init_regions(ctx, buf, 256); + + KUNIT_EXPECT_STREQ(test, (char *)buf, ""); + } + + dbgfs_set_targets(ctx, 0, NULL); + damon_destroy_ctx(ctx); +} + +static struct kunit_case damon_test_cases[] = { + KUNIT_CASE(damon_dbgfs_test_str_to_ints), + KUNIT_CASE(damon_dbgfs_test_set_targets), + KUNIT_CASE(damon_dbgfs_test_set_init_regions), + {}, +}; + +static struct kunit_suite damon_test_suite = { + .name = "damon-dbgfs", + .test_cases = damon_test_cases, +}; +kunit_test_suite(damon_test_suite); + +#endif /* _DAMON_TEST_H */ + +#endif /* CONFIG_DAMON_KUNIT_TEST */ diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c new file mode 100644 index 000000000..b3f454a5c --- /dev/null +++ b/mm/damon/dbgfs.c @@ -0,0 +1,1114 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DAMON Debugfs Interface + * + * Author: SeongJae Park <sjpark@amazon.de> + */ + +#define pr_fmt(fmt) "damon-dbgfs: " fmt + +#include <linux/damon.h> +#include <linux/debugfs.h> +#include <linux/file.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/page_idle.h> +#include <linux/slab.h> + +static struct damon_ctx **dbgfs_ctxs; +static int dbgfs_nr_ctxs; +static struct dentry **dbgfs_dirs; +static DEFINE_MUTEX(damon_dbgfs_lock); + +/* + * Returns non-empty string on success, negative error code otherwise. + */ +static char *user_input_str(const char __user *buf, size_t count, loff_t *ppos) +{ + char *kbuf; + ssize_t ret; + + /* We do not accept continuous write */ + if (*ppos) + return ERR_PTR(-EINVAL); + + kbuf = kmalloc(count + 1, GFP_KERNEL | __GFP_NOWARN); + if (!kbuf) + return ERR_PTR(-ENOMEM); + + ret = simple_write_to_buffer(kbuf, count + 1, ppos, buf, count); + if (ret != count) { + kfree(kbuf); + return ERR_PTR(-EIO); + } + kbuf[ret] = '\0'; + + return kbuf; +} + +static ssize_t dbgfs_attrs_read(struct file *file, + char __user *buf, size_t count, loff_t *ppos) +{ + struct damon_ctx *ctx = file->private_data; + char kbuf[128]; + int ret; + + mutex_lock(&ctx->kdamond_lock); + ret = scnprintf(kbuf, ARRAY_SIZE(kbuf), "%lu %lu %lu %lu %lu\n", + ctx->attrs.sample_interval, ctx->attrs.aggr_interval, + ctx->attrs.ops_update_interval, + ctx->attrs.min_nr_regions, ctx->attrs.max_nr_regions); + mutex_unlock(&ctx->kdamond_lock); + + return simple_read_from_buffer(buf, count, ppos, kbuf, ret); +} + +static ssize_t dbgfs_attrs_write(struct file *file, + const char __user *buf, size_t count, loff_t *ppos) +{ + struct damon_ctx *ctx = file->private_data; + struct damon_attrs attrs; + char *kbuf; + ssize_t ret; + + kbuf = user_input_str(buf, count, ppos); + if (IS_ERR(kbuf)) + return PTR_ERR(kbuf); + + if (sscanf(kbuf, "%lu %lu %lu %lu %lu", + &attrs.sample_interval, &attrs.aggr_interval, + &attrs.ops_update_interval, + &attrs.min_nr_regions, + &attrs.max_nr_regions) != 5) { + ret = -EINVAL; + goto out; + } + + mutex_lock(&ctx->kdamond_lock); + if (ctx->kdamond) { + ret = -EBUSY; + goto unlock_out; + } + + ret = damon_set_attrs(ctx, &attrs); + if (!ret) + ret = count; +unlock_out: + mutex_unlock(&ctx->kdamond_lock); +out: + kfree(kbuf); + return ret; +} + +/* + * Return corresponding dbgfs' scheme action value (int) for the given + * damos_action if the given damos_action value is valid and supported by + * dbgfs, negative error code otherwise. + */ +static int damos_action_to_dbgfs_scheme_action(enum damos_action action) +{ + switch (action) { + case DAMOS_WILLNEED: + return 0; + case DAMOS_COLD: + return 1; + case DAMOS_PAGEOUT: + return 2; + case DAMOS_HUGEPAGE: + return 3; + case DAMOS_NOHUGEPAGE: + return 4; + case DAMOS_STAT: + return 5; + default: + return -EINVAL; + } +} + +static ssize_t sprint_schemes(struct damon_ctx *c, char *buf, ssize_t len) +{ + struct damos *s; + int written = 0; + int rc; + + damon_for_each_scheme(s, c) { + rc = scnprintf(&buf[written], len - written, + "%lu %lu %u %u %u %u %d %lu %lu %lu %u %u %u %d %lu %lu %lu %lu %lu %lu %lu %lu %lu\n", + s->pattern.min_sz_region, + s->pattern.max_sz_region, + s->pattern.min_nr_accesses, + s->pattern.max_nr_accesses, + s->pattern.min_age_region, + s->pattern.max_age_region, + damos_action_to_dbgfs_scheme_action(s->action), + s->quota.ms, s->quota.sz, + s->quota.reset_interval, + s->quota.weight_sz, + s->quota.weight_nr_accesses, + s->quota.weight_age, + s->wmarks.metric, s->wmarks.interval, + s->wmarks.high, s->wmarks.mid, s->wmarks.low, + s->stat.nr_tried, s->stat.sz_tried, + s->stat.nr_applied, s->stat.sz_applied, + s->stat.qt_exceeds); + if (!rc) + return -ENOMEM; + + written += rc; + } + return written; +} + +static ssize_t dbgfs_schemes_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + struct damon_ctx *ctx = file->private_data; + char *kbuf; + ssize_t len; + + kbuf = kmalloc(count, GFP_KERNEL | __GFP_NOWARN); + if (!kbuf) + return -ENOMEM; + + mutex_lock(&ctx->kdamond_lock); + len = sprint_schemes(ctx, kbuf, count); + mutex_unlock(&ctx->kdamond_lock); + if (len < 0) + goto out; + len = simple_read_from_buffer(buf, count, ppos, kbuf, len); + +out: + kfree(kbuf); + return len; +} + +static void free_schemes_arr(struct damos **schemes, ssize_t nr_schemes) +{ + ssize_t i; + + for (i = 0; i < nr_schemes; i++) + kfree(schemes[i]); + kfree(schemes); +} + +/* + * Return corresponding damos_action for the given dbgfs input for a scheme + * action if the input is valid, negative error code otherwise. + */ +static enum damos_action dbgfs_scheme_action_to_damos_action(int dbgfs_action) +{ + switch (dbgfs_action) { + case 0: + return DAMOS_WILLNEED; + case 1: + return DAMOS_COLD; + case 2: + return DAMOS_PAGEOUT; + case 3: + return DAMOS_HUGEPAGE; + case 4: + return DAMOS_NOHUGEPAGE; + case 5: + return DAMOS_STAT; + default: + return -EINVAL; + } +} + +/* + * Converts a string into an array of struct damos pointers + * + * Returns an array of struct damos pointers that converted if the conversion + * success, or NULL otherwise. + */ +static struct damos **str_to_schemes(const char *str, ssize_t len, + ssize_t *nr_schemes) +{ + struct damos *scheme, **schemes; + const int max_nr_schemes = 256; + int pos = 0, parsed, ret; + unsigned int action_input; + enum damos_action action; + + schemes = kmalloc_array(max_nr_schemes, sizeof(scheme), + GFP_KERNEL); + if (!schemes) + return NULL; + + *nr_schemes = 0; + while (pos < len && *nr_schemes < max_nr_schemes) { + struct damos_access_pattern pattern = {}; + struct damos_quota quota = {}; + struct damos_watermarks wmarks; + + ret = sscanf(&str[pos], + "%lu %lu %u %u %u %u %u %lu %lu %lu %u %u %u %u %lu %lu %lu %lu%n", + &pattern.min_sz_region, &pattern.max_sz_region, + &pattern.min_nr_accesses, + &pattern.max_nr_accesses, + &pattern.min_age_region, + &pattern.max_age_region, + &action_input, "a.ms, + "a.sz, "a.reset_interval, + "a.weight_sz, "a.weight_nr_accesses, + "a.weight_age, &wmarks.metric, + &wmarks.interval, &wmarks.high, &wmarks.mid, + &wmarks.low, &parsed); + if (ret != 18) + break; + action = dbgfs_scheme_action_to_damos_action(action_input); + if ((int)action < 0) + goto fail; + + if (pattern.min_sz_region > pattern.max_sz_region || + pattern.min_nr_accesses > pattern.max_nr_accesses || + pattern.min_age_region > pattern.max_age_region) + goto fail; + + if (wmarks.high < wmarks.mid || wmarks.high < wmarks.low || + wmarks.mid < wmarks.low) + goto fail; + + pos += parsed; + scheme = damon_new_scheme(&pattern, action, "a, &wmarks); + if (!scheme) + goto fail; + + schemes[*nr_schemes] = scheme; + *nr_schemes += 1; + } + return schemes; +fail: + free_schemes_arr(schemes, *nr_schemes); + return NULL; +} + +static ssize_t dbgfs_schemes_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct damon_ctx *ctx = file->private_data; + char *kbuf; + struct damos **schemes; + ssize_t nr_schemes = 0, ret; + + kbuf = user_input_str(buf, count, ppos); + if (IS_ERR(kbuf)) + return PTR_ERR(kbuf); + + schemes = str_to_schemes(kbuf, count, &nr_schemes); + if (!schemes) { + ret = -EINVAL; + goto out; + } + + mutex_lock(&ctx->kdamond_lock); + if (ctx->kdamond) { + ret = -EBUSY; + goto unlock_out; + } + + damon_set_schemes(ctx, schemes, nr_schemes); + ret = count; + nr_schemes = 0; + +unlock_out: + mutex_unlock(&ctx->kdamond_lock); + free_schemes_arr(schemes, nr_schemes); +out: + kfree(kbuf); + return ret; +} + +static ssize_t sprint_target_ids(struct damon_ctx *ctx, char *buf, ssize_t len) +{ + struct damon_target *t; + int id; + int written = 0; + int rc; + + damon_for_each_target(t, ctx) { + if (damon_target_has_pid(ctx)) + /* Show pid numbers to debugfs users */ + id = pid_vnr(t->pid); + else + /* Show 42 for physical address space, just for fun */ + id = 42; + + rc = scnprintf(&buf[written], len - written, "%d ", id); + if (!rc) + return -ENOMEM; + written += rc; + } + if (written) + written -= 1; + written += scnprintf(&buf[written], len - written, "\n"); + return written; +} + +static ssize_t dbgfs_target_ids_read(struct file *file, + char __user *buf, size_t count, loff_t *ppos) +{ + struct damon_ctx *ctx = file->private_data; + ssize_t len; + char ids_buf[320]; + + mutex_lock(&ctx->kdamond_lock); + len = sprint_target_ids(ctx, ids_buf, 320); + mutex_unlock(&ctx->kdamond_lock); + if (len < 0) + return len; + + return simple_read_from_buffer(buf, count, ppos, ids_buf, len); +} + +/* + * Converts a string into an integers array + * + * Returns an array of integers array if the conversion success, or NULL + * otherwise. + */ +static int *str_to_ints(const char *str, ssize_t len, ssize_t *nr_ints) +{ + int *array; + const int max_nr_ints = 32; + int nr; + int pos = 0, parsed, ret; + + *nr_ints = 0; + array = kmalloc_array(max_nr_ints, sizeof(*array), GFP_KERNEL); + if (!array) + return NULL; + while (*nr_ints < max_nr_ints && pos < len) { + ret = sscanf(&str[pos], "%d%n", &nr, &parsed); + pos += parsed; + if (ret != 1) + break; + array[*nr_ints] = nr; + *nr_ints += 1; + } + + return array; +} + +static void dbgfs_put_pids(struct pid **pids, int nr_pids) +{ + int i; + + for (i = 0; i < nr_pids; i++) + put_pid(pids[i]); +} + +/* + * Converts a string into an struct pid pointers array + * + * Returns an array of struct pid pointers if the conversion success, or NULL + * otherwise. + */ +static struct pid **str_to_pids(const char *str, ssize_t len, ssize_t *nr_pids) +{ + int *ints; + ssize_t nr_ints; + struct pid **pids; + + *nr_pids = 0; + + ints = str_to_ints(str, len, &nr_ints); + if (!ints) + return NULL; + + pids = kmalloc_array(nr_ints, sizeof(*pids), GFP_KERNEL); + if (!pids) + goto out; + + for (; *nr_pids < nr_ints; (*nr_pids)++) { + pids[*nr_pids] = find_get_pid(ints[*nr_pids]); + if (!pids[*nr_pids]) { + dbgfs_put_pids(pids, *nr_pids); + kfree(ints); + kfree(pids); + return NULL; + } + } + +out: + kfree(ints); + return pids; +} + +/* + * dbgfs_set_targets() - Set monitoring targets. + * @ctx: monitoring context + * @nr_targets: number of targets + * @pids: array of target pids (size is same to @nr_targets) + * + * This function should not be called while the kdamond is running. @pids is + * ignored if the context is not configured to have pid in each target. On + * failure, reference counts of all pids in @pids are decremented. + * + * Return: 0 on success, negative error code otherwise. + */ +static int dbgfs_set_targets(struct damon_ctx *ctx, ssize_t nr_targets, + struct pid **pids) +{ + ssize_t i; + struct damon_target *t, *next; + + damon_for_each_target_safe(t, next, ctx) { + if (damon_target_has_pid(ctx)) + put_pid(t->pid); + damon_destroy_target(t); + } + + for (i = 0; i < nr_targets; i++) { + t = damon_new_target(); + if (!t) { + damon_for_each_target_safe(t, next, ctx) + damon_destroy_target(t); + if (damon_target_has_pid(ctx)) + dbgfs_put_pids(pids, nr_targets); + return -ENOMEM; + } + if (damon_target_has_pid(ctx)) + t->pid = pids[i]; + damon_add_target(ctx, t); + } + + return 0; +} + +static ssize_t dbgfs_target_ids_write(struct file *file, + const char __user *buf, size_t count, loff_t *ppos) +{ + struct damon_ctx *ctx = file->private_data; + bool id_is_pid = true; + char *kbuf; + struct pid **target_pids = NULL; + ssize_t nr_targets; + ssize_t ret; + + kbuf = user_input_str(buf, count, ppos); + if (IS_ERR(kbuf)) + return PTR_ERR(kbuf); + + if (!strncmp(kbuf, "paddr\n", count)) { + id_is_pid = false; + nr_targets = 1; + } + + if (id_is_pid) { + target_pids = str_to_pids(kbuf, count, &nr_targets); + if (!target_pids) { + ret = -ENOMEM; + goto out; + } + } + + mutex_lock(&ctx->kdamond_lock); + if (ctx->kdamond) { + if (id_is_pid) + dbgfs_put_pids(target_pids, nr_targets); + ret = -EBUSY; + goto unlock_out; + } + + /* remove previously set targets */ + dbgfs_set_targets(ctx, 0, NULL); + if (!nr_targets) { + ret = count; + goto unlock_out; + } + + /* Configure the context for the address space type */ + if (id_is_pid) + ret = damon_select_ops(ctx, DAMON_OPS_VADDR); + else + ret = damon_select_ops(ctx, DAMON_OPS_PADDR); + if (ret) + goto unlock_out; + + ret = dbgfs_set_targets(ctx, nr_targets, target_pids); + if (!ret) + ret = count; + +unlock_out: + mutex_unlock(&ctx->kdamond_lock); + kfree(target_pids); +out: + kfree(kbuf); + return ret; +} + +static ssize_t sprint_init_regions(struct damon_ctx *c, char *buf, ssize_t len) +{ + struct damon_target *t; + struct damon_region *r; + int target_idx = 0; + int written = 0; + int rc; + + damon_for_each_target(t, c) { + damon_for_each_region(r, t) { + rc = scnprintf(&buf[written], len - written, + "%d %lu %lu\n", + target_idx, r->ar.start, r->ar.end); + if (!rc) + return -ENOMEM; + written += rc; + } + target_idx++; + } + return written; +} + +static ssize_t dbgfs_init_regions_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + struct damon_ctx *ctx = file->private_data; + char *kbuf; + ssize_t len; + + kbuf = kmalloc(count, GFP_KERNEL | __GFP_NOWARN); + if (!kbuf) + return -ENOMEM; + + mutex_lock(&ctx->kdamond_lock); + if (ctx->kdamond) { + mutex_unlock(&ctx->kdamond_lock); + len = -EBUSY; + goto out; + } + + len = sprint_init_regions(ctx, kbuf, count); + mutex_unlock(&ctx->kdamond_lock); + if (len < 0) + goto out; + len = simple_read_from_buffer(buf, count, ppos, kbuf, len); + +out: + kfree(kbuf); + return len; +} + +static int add_init_region(struct damon_ctx *c, int target_idx, + struct damon_addr_range *ar) +{ + struct damon_target *t; + struct damon_region *r, *prev; + unsigned long idx = 0; + int rc = -EINVAL; + + if (ar->start >= ar->end) + return -EINVAL; + + damon_for_each_target(t, c) { + if (idx++ == target_idx) { + r = damon_new_region(ar->start, ar->end); + if (!r) + return -ENOMEM; + damon_add_region(r, t); + if (damon_nr_regions(t) > 1) { + prev = damon_prev_region(r); + if (prev->ar.end > r->ar.start) { + damon_destroy_region(r, t); + return -EINVAL; + } + } + rc = 0; + } + } + return rc; +} + +static int set_init_regions(struct damon_ctx *c, const char *str, ssize_t len) +{ + struct damon_target *t; + struct damon_region *r, *next; + int pos = 0, parsed, ret; + int target_idx; + struct damon_addr_range ar; + int err; + + damon_for_each_target(t, c) { + damon_for_each_region_safe(r, next, t) + damon_destroy_region(r, t); + } + + while (pos < len) { + ret = sscanf(&str[pos], "%d %lu %lu%n", + &target_idx, &ar.start, &ar.end, &parsed); + if (ret != 3) + break; + err = add_init_region(c, target_idx, &ar); + if (err) + goto fail; + pos += parsed; + } + + return 0; + +fail: + damon_for_each_target(t, c) { + damon_for_each_region_safe(r, next, t) + damon_destroy_region(r, t); + } + return err; +} + +static ssize_t dbgfs_init_regions_write(struct file *file, + const char __user *buf, size_t count, + loff_t *ppos) +{ + struct damon_ctx *ctx = file->private_data; + char *kbuf; + ssize_t ret = count; + int err; + + kbuf = user_input_str(buf, count, ppos); + if (IS_ERR(kbuf)) + return PTR_ERR(kbuf); + + mutex_lock(&ctx->kdamond_lock); + if (ctx->kdamond) { + ret = -EBUSY; + goto unlock_out; + } + + err = set_init_regions(ctx, kbuf, ret); + if (err) + ret = err; + +unlock_out: + mutex_unlock(&ctx->kdamond_lock); + kfree(kbuf); + return ret; +} + +static ssize_t dbgfs_kdamond_pid_read(struct file *file, + char __user *buf, size_t count, loff_t *ppos) +{ + struct damon_ctx *ctx = file->private_data; + char *kbuf; + ssize_t len; + + kbuf = kmalloc(count, GFP_KERNEL | __GFP_NOWARN); + if (!kbuf) + return -ENOMEM; + + mutex_lock(&ctx->kdamond_lock); + if (ctx->kdamond) + len = scnprintf(kbuf, count, "%d\n", ctx->kdamond->pid); + else + len = scnprintf(kbuf, count, "none\n"); + mutex_unlock(&ctx->kdamond_lock); + if (!len) + goto out; + len = simple_read_from_buffer(buf, count, ppos, kbuf, len); + +out: + kfree(kbuf); + return len; +} + +static int damon_dbgfs_open(struct inode *inode, struct file *file) +{ + file->private_data = inode->i_private; + + return nonseekable_open(inode, file); +} + +static const struct file_operations attrs_fops = { + .open = damon_dbgfs_open, + .read = dbgfs_attrs_read, + .write = dbgfs_attrs_write, +}; + +static const struct file_operations schemes_fops = { + .open = damon_dbgfs_open, + .read = dbgfs_schemes_read, + .write = dbgfs_schemes_write, +}; + +static const struct file_operations target_ids_fops = { + .open = damon_dbgfs_open, + .read = dbgfs_target_ids_read, + .write = dbgfs_target_ids_write, +}; + +static const struct file_operations init_regions_fops = { + .open = damon_dbgfs_open, + .read = dbgfs_init_regions_read, + .write = dbgfs_init_regions_write, +}; + +static const struct file_operations kdamond_pid_fops = { + .open = damon_dbgfs_open, + .read = dbgfs_kdamond_pid_read, +}; + +static void dbgfs_fill_ctx_dir(struct dentry *dir, struct damon_ctx *ctx) +{ + const char * const file_names[] = {"attrs", "schemes", "target_ids", + "init_regions", "kdamond_pid"}; + const struct file_operations *fops[] = {&attrs_fops, &schemes_fops, + &target_ids_fops, &init_regions_fops, &kdamond_pid_fops}; + int i; + + for (i = 0; i < ARRAY_SIZE(file_names); i++) + debugfs_create_file(file_names[i], 0600, dir, ctx, fops[i]); +} + +static void dbgfs_before_terminate(struct damon_ctx *ctx) +{ + struct damon_target *t, *next; + + if (!damon_target_has_pid(ctx)) + return; + + mutex_lock(&ctx->kdamond_lock); + damon_for_each_target_safe(t, next, ctx) { + put_pid(t->pid); + damon_destroy_target(t); + } + mutex_unlock(&ctx->kdamond_lock); +} + +static struct damon_ctx *dbgfs_new_ctx(void) +{ + struct damon_ctx *ctx; + + ctx = damon_new_ctx(); + if (!ctx) + return NULL; + + if (damon_select_ops(ctx, DAMON_OPS_VADDR) && + damon_select_ops(ctx, DAMON_OPS_PADDR)) { + damon_destroy_ctx(ctx); + return NULL; + } + ctx->callback.before_terminate = dbgfs_before_terminate; + return ctx; +} + +static void dbgfs_destroy_ctx(struct damon_ctx *ctx) +{ + damon_destroy_ctx(ctx); +} + +/* + * Make a context of @name and create a debugfs directory for it. + * + * This function should be called while holding damon_dbgfs_lock. + * + * Returns 0 on success, negative error code otherwise. + */ +static int dbgfs_mk_context(char *name) +{ + struct dentry *root, **new_dirs, *new_dir; + struct damon_ctx **new_ctxs, *new_ctx; + + if (damon_nr_running_ctxs()) + return -EBUSY; + + new_ctxs = krealloc(dbgfs_ctxs, sizeof(*dbgfs_ctxs) * + (dbgfs_nr_ctxs + 1), GFP_KERNEL); + if (!new_ctxs) + return -ENOMEM; + dbgfs_ctxs = new_ctxs; + + new_dirs = krealloc(dbgfs_dirs, sizeof(*dbgfs_dirs) * + (dbgfs_nr_ctxs + 1), GFP_KERNEL); + if (!new_dirs) + return -ENOMEM; + dbgfs_dirs = new_dirs; + + root = dbgfs_dirs[0]; + if (!root) + return -ENOENT; + + new_dir = debugfs_create_dir(name, root); + /* Below check is required for a potential duplicated name case */ + if (IS_ERR(new_dir)) + return PTR_ERR(new_dir); + dbgfs_dirs[dbgfs_nr_ctxs] = new_dir; + + new_ctx = dbgfs_new_ctx(); + if (!new_ctx) { + debugfs_remove(new_dir); + dbgfs_dirs[dbgfs_nr_ctxs] = NULL; + return -ENOMEM; + } + + dbgfs_ctxs[dbgfs_nr_ctxs] = new_ctx; + dbgfs_fill_ctx_dir(dbgfs_dirs[dbgfs_nr_ctxs], + dbgfs_ctxs[dbgfs_nr_ctxs]); + dbgfs_nr_ctxs++; + + return 0; +} + +static ssize_t dbgfs_mk_context_write(struct file *file, + const char __user *buf, size_t count, loff_t *ppos) +{ + char *kbuf; + char *ctx_name; + ssize_t ret; + + kbuf = user_input_str(buf, count, ppos); + if (IS_ERR(kbuf)) + return PTR_ERR(kbuf); + ctx_name = kmalloc(count + 1, GFP_KERNEL); + if (!ctx_name) { + kfree(kbuf); + return -ENOMEM; + } + + /* Trim white space */ + if (sscanf(kbuf, "%s", ctx_name) != 1) { + ret = -EINVAL; + goto out; + } + + mutex_lock(&damon_dbgfs_lock); + ret = dbgfs_mk_context(ctx_name); + if (!ret) + ret = count; + mutex_unlock(&damon_dbgfs_lock); + +out: + kfree(kbuf); + kfree(ctx_name); + return ret; +} + +/* + * Remove a context of @name and its debugfs directory. + * + * This function should be called while holding damon_dbgfs_lock. + * + * Return 0 on success, negative error code otherwise. + */ +static int dbgfs_rm_context(char *name) +{ + struct dentry *root, *dir, **new_dirs; + struct inode *inode; + struct damon_ctx **new_ctxs; + int i, j; + int ret = 0; + + if (damon_nr_running_ctxs()) + return -EBUSY; + + root = dbgfs_dirs[0]; + if (!root) + return -ENOENT; + + dir = debugfs_lookup(name, root); + if (!dir) + return -ENOENT; + + inode = d_inode(dir); + if (!S_ISDIR(inode->i_mode)) { + ret = -EINVAL; + goto out_dput; + } + + new_dirs = kmalloc_array(dbgfs_nr_ctxs - 1, sizeof(*dbgfs_dirs), + GFP_KERNEL); + if (!new_dirs) { + ret = -ENOMEM; + goto out_dput; + } + + new_ctxs = kmalloc_array(dbgfs_nr_ctxs - 1, sizeof(*dbgfs_ctxs), + GFP_KERNEL); + if (!new_ctxs) { + ret = -ENOMEM; + goto out_new_dirs; + } + + for (i = 0, j = 0; i < dbgfs_nr_ctxs; i++) { + if (dbgfs_dirs[i] == dir) { + debugfs_remove(dbgfs_dirs[i]); + dbgfs_destroy_ctx(dbgfs_ctxs[i]); + continue; + } + new_dirs[j] = dbgfs_dirs[i]; + new_ctxs[j++] = dbgfs_ctxs[i]; + } + + kfree(dbgfs_dirs); + kfree(dbgfs_ctxs); + + dbgfs_dirs = new_dirs; + dbgfs_ctxs = new_ctxs; + dbgfs_nr_ctxs--; + + goto out_dput; + +out_new_dirs: + kfree(new_dirs); +out_dput: + dput(dir); + return ret; +} + +static ssize_t dbgfs_rm_context_write(struct file *file, + const char __user *buf, size_t count, loff_t *ppos) +{ + char *kbuf; + ssize_t ret; + char *ctx_name; + + kbuf = user_input_str(buf, count, ppos); + if (IS_ERR(kbuf)) + return PTR_ERR(kbuf); + ctx_name = kmalloc(count + 1, GFP_KERNEL); + if (!ctx_name) { + kfree(kbuf); + return -ENOMEM; + } + + /* Trim white space */ + if (sscanf(kbuf, "%s", ctx_name) != 1) { + ret = -EINVAL; + goto out; + } + + mutex_lock(&damon_dbgfs_lock); + ret = dbgfs_rm_context(ctx_name); + if (!ret) + ret = count; + mutex_unlock(&damon_dbgfs_lock); + +out: + kfree(kbuf); + kfree(ctx_name); + return ret; +} + +static ssize_t dbgfs_monitor_on_read(struct file *file, + char __user *buf, size_t count, loff_t *ppos) +{ + char monitor_on_buf[5]; + bool monitor_on = damon_nr_running_ctxs() != 0; + int len; + + len = scnprintf(monitor_on_buf, 5, monitor_on ? "on\n" : "off\n"); + + return simple_read_from_buffer(buf, count, ppos, monitor_on_buf, len); +} + +static ssize_t dbgfs_monitor_on_write(struct file *file, + const char __user *buf, size_t count, loff_t *ppos) +{ + ssize_t ret; + char *kbuf; + + kbuf = user_input_str(buf, count, ppos); + if (IS_ERR(kbuf)) + return PTR_ERR(kbuf); + + /* Remove white space */ + if (sscanf(kbuf, "%s", kbuf) != 1) { + kfree(kbuf); + return -EINVAL; + } + + mutex_lock(&damon_dbgfs_lock); + if (!strncmp(kbuf, "on", count)) { + int i; + + for (i = 0; i < dbgfs_nr_ctxs; i++) { + if (damon_targets_empty(dbgfs_ctxs[i])) { + kfree(kbuf); + mutex_unlock(&damon_dbgfs_lock); + return -EINVAL; + } + } + ret = damon_start(dbgfs_ctxs, dbgfs_nr_ctxs, true); + } else if (!strncmp(kbuf, "off", count)) { + ret = damon_stop(dbgfs_ctxs, dbgfs_nr_ctxs); + } else { + ret = -EINVAL; + } + mutex_unlock(&damon_dbgfs_lock); + + if (!ret) + ret = count; + kfree(kbuf); + return ret; +} + +static const struct file_operations mk_contexts_fops = { + .write = dbgfs_mk_context_write, +}; + +static const struct file_operations rm_contexts_fops = { + .write = dbgfs_rm_context_write, +}; + +static const struct file_operations monitor_on_fops = { + .read = dbgfs_monitor_on_read, + .write = dbgfs_monitor_on_write, +}; + +static int __init __damon_dbgfs_init(void) +{ + struct dentry *dbgfs_root; + const char * const file_names[] = {"mk_contexts", "rm_contexts", + "monitor_on"}; + const struct file_operations *fops[] = {&mk_contexts_fops, + &rm_contexts_fops, &monitor_on_fops}; + int i; + + dbgfs_root = debugfs_create_dir("damon", NULL); + + for (i = 0; i < ARRAY_SIZE(file_names); i++) + debugfs_create_file(file_names[i], 0600, dbgfs_root, NULL, + fops[i]); + dbgfs_fill_ctx_dir(dbgfs_root, dbgfs_ctxs[0]); + + dbgfs_dirs = kmalloc(sizeof(dbgfs_root), GFP_KERNEL); + if (!dbgfs_dirs) { + debugfs_remove(dbgfs_root); + return -ENOMEM; + } + dbgfs_dirs[0] = dbgfs_root; + + return 0; +} + +/* + * Functions for the initialization + */ + +static int __init damon_dbgfs_init(void) +{ + int rc = -ENOMEM; + + mutex_lock(&damon_dbgfs_lock); + dbgfs_ctxs = kmalloc(sizeof(*dbgfs_ctxs), GFP_KERNEL); + if (!dbgfs_ctxs) + goto out; + dbgfs_ctxs[0] = dbgfs_new_ctx(); + if (!dbgfs_ctxs[0]) { + kfree(dbgfs_ctxs); + goto out; + } + dbgfs_nr_ctxs = 1; + + rc = __damon_dbgfs_init(); + if (rc) { + kfree(dbgfs_ctxs[0]); + kfree(dbgfs_ctxs); + pr_err("%s: dbgfs init failed\n", __func__); + } + +out: + mutex_unlock(&damon_dbgfs_lock); + return rc; +} + +module_init(damon_dbgfs_init); + +#include "dbgfs-test.h" diff --git a/mm/damon/lru_sort.c b/mm/damon/lru_sort.c new file mode 100644 index 000000000..63bdad20d --- /dev/null +++ b/mm/damon/lru_sort.c @@ -0,0 +1,340 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DAMON-based LRU-lists Sorting + * + * Author: SeongJae Park <sj@kernel.org> + */ + +#define pr_fmt(fmt) "damon-lru-sort: " fmt + +#include <linux/damon.h> +#include <linux/ioport.h> +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/workqueue.h> + +#include "modules-common.h" + +#ifdef MODULE_PARAM_PREFIX +#undef MODULE_PARAM_PREFIX +#endif +#define MODULE_PARAM_PREFIX "damon_lru_sort." + +/* + * Enable or disable DAMON_LRU_SORT. + * + * You can enable DAMON_LRU_SORT by setting the value of this parameter as + * ``Y``. Setting it as ``N`` disables DAMON_LRU_SORT. Note that + * DAMON_LRU_SORT could do no real monitoring and LRU-lists sorting due to the + * watermarks-based activation condition. Refer to below descriptions for the + * watermarks parameter for this. + */ +static bool enabled __read_mostly; + +/* + * Make DAMON_LRU_SORT reads the input parameters again, except ``enabled``. + * + * Input parameters that updated while DAMON_LRU_SORT is running are not + * applied by default. Once this parameter is set as ``Y``, DAMON_LRU_SORT + * reads values of parametrs except ``enabled`` again. Once the re-reading is + * done, this parameter is set as ``N``. If invalid parameters are found while + * the re-reading, DAMON_LRU_SORT will be disabled. + */ +static bool commit_inputs __read_mostly; +module_param(commit_inputs, bool, 0600); + +/* + * Access frequency threshold for hot memory regions identification in permil. + * + * If a memory region is accessed in frequency of this or higher, + * DAMON_LRU_SORT identifies the region as hot, and mark it as accessed on the + * LRU list, so that it could not be reclaimed under memory pressure. 50% by + * default. + */ +static unsigned long hot_thres_access_freq = 500; +module_param(hot_thres_access_freq, ulong, 0600); + +/* + * Time threshold for cold memory regions identification in microseconds. + * + * If a memory region is not accessed for this or longer time, DAMON_LRU_SORT + * identifies the region as cold, and mark it as unaccessed on the LRU list, so + * that it could be reclaimed first under memory pressure. 120 seconds by + * default. + */ +static unsigned long cold_min_age __read_mostly = 120000000; +module_param(cold_min_age, ulong, 0600); + +static struct damos_quota damon_lru_sort_quota = { + /* Use up to 10 ms per 1 sec, by default */ + .ms = 10, + .sz = 0, + .reset_interval = 1000, + /* Within the quota, mark hotter regions accessed first. */ + .weight_sz = 0, + .weight_nr_accesses = 1, + .weight_age = 0, +}; +DEFINE_DAMON_MODULES_DAMOS_TIME_QUOTA(damon_lru_sort_quota); + +static struct damos_watermarks damon_lru_sort_wmarks = { + .metric = DAMOS_WMARK_FREE_MEM_RATE, + .interval = 5000000, /* 5 seconds */ + .high = 200, /* 20 percent */ + .mid = 150, /* 15 percent */ + .low = 50, /* 5 percent */ +}; +DEFINE_DAMON_MODULES_WMARKS_PARAMS(damon_lru_sort_wmarks); + +static struct damon_attrs damon_lru_sort_mon_attrs = { + .sample_interval = 5000, /* 5 ms */ + .aggr_interval = 100000, /* 100 ms */ + .ops_update_interval = 0, + .min_nr_regions = 10, + .max_nr_regions = 1000, +}; +DEFINE_DAMON_MODULES_MON_ATTRS_PARAMS(damon_lru_sort_mon_attrs); + +/* + * Start of the target memory region in physical address. + * + * The start physical address of memory region that DAMON_LRU_SORT will do work + * against. By default, biggest System RAM is used as the region. + */ +static unsigned long monitor_region_start __read_mostly; +module_param(monitor_region_start, ulong, 0600); + +/* + * End of the target memory region in physical address. + * + * The end physical address of memory region that DAMON_LRU_SORT will do work + * against. By default, biggest System RAM is used as the region. + */ +static unsigned long monitor_region_end __read_mostly; +module_param(monitor_region_end, ulong, 0600); + +/* + * PID of the DAMON thread + * + * If DAMON_LRU_SORT is enabled, this becomes the PID of the worker thread. + * Else, -1. + */ +static int kdamond_pid __read_mostly = -1; +module_param(kdamond_pid, int, 0400); + +static struct damos_stat damon_lru_sort_hot_stat; +DEFINE_DAMON_MODULES_DAMOS_STATS_PARAMS(damon_lru_sort_hot_stat, + lru_sort_tried_hot_regions, lru_sorted_hot_regions, + hot_quota_exceeds); + +static struct damos_stat damon_lru_sort_cold_stat; +DEFINE_DAMON_MODULES_DAMOS_STATS_PARAMS(damon_lru_sort_cold_stat, + lru_sort_tried_cold_regions, lru_sorted_cold_regions, + cold_quota_exceeds); + +static struct damos_access_pattern damon_lru_sort_stub_pattern = { + /* Find regions having PAGE_SIZE or larger size */ + .min_sz_region = PAGE_SIZE, + .max_sz_region = ULONG_MAX, + /* no matter its access frequency */ + .min_nr_accesses = 0, + .max_nr_accesses = UINT_MAX, + /* no matter its age */ + .min_age_region = 0, + .max_age_region = UINT_MAX, +}; + +static struct damon_ctx *ctx; +static struct damon_target *target; + +static struct damos *damon_lru_sort_new_scheme( + struct damos_access_pattern *pattern, enum damos_action action) +{ + struct damos_quota quota = damon_lru_sort_quota; + + /* Use half of total quota for hot/cold pages sorting */ + quota.ms = quota.ms / 2; + + return damon_new_scheme( + /* find the pattern, and */ + pattern, + /* (de)prioritize on LRU-lists */ + action, + /* under the quota. */ + "a, + /* (De)activate this according to the watermarks. */ + &damon_lru_sort_wmarks); +} + +/* Create a DAMON-based operation scheme for hot memory regions */ +static struct damos *damon_lru_sort_new_hot_scheme(unsigned int hot_thres) +{ + struct damos_access_pattern pattern = damon_lru_sort_stub_pattern; + + pattern.min_nr_accesses = hot_thres; + return damon_lru_sort_new_scheme(&pattern, DAMOS_LRU_PRIO); +} + +/* Create a DAMON-based operation scheme for cold memory regions */ +static struct damos *damon_lru_sort_new_cold_scheme(unsigned int cold_thres) +{ + struct damos_access_pattern pattern = damon_lru_sort_stub_pattern; + + pattern.max_nr_accesses = 0; + pattern.min_age_region = cold_thres; + return damon_lru_sort_new_scheme(&pattern, DAMOS_LRU_DEPRIO); +} + +static int damon_lru_sort_apply_parameters(void) +{ + struct damos *scheme; + unsigned int hot_thres, cold_thres; + int err = 0; + + err = damon_set_attrs(ctx, &damon_lru_sort_mon_attrs); + if (err) + return err; + + hot_thres = damon_max_nr_accesses(&damon_lru_sort_mon_attrs) * + hot_thres_access_freq / 1000; + scheme = damon_lru_sort_new_hot_scheme(hot_thres); + if (!scheme) + return -ENOMEM; + damon_set_schemes(ctx, &scheme, 1); + + cold_thres = cold_min_age / damon_lru_sort_mon_attrs.aggr_interval; + scheme = damon_lru_sort_new_cold_scheme(cold_thres); + if (!scheme) + return -ENOMEM; + damon_add_scheme(ctx, scheme); + + return damon_set_region_biggest_system_ram_default(target, + &monitor_region_start, + &monitor_region_end); +} + +static int damon_lru_sort_turn(bool on) +{ + int err; + + if (!on) { + err = damon_stop(&ctx, 1); + if (!err) + kdamond_pid = -1; + return err; + } + + err = damon_lru_sort_apply_parameters(); + if (err) + return err; + + err = damon_start(&ctx, 1, true); + if (err) + return err; + kdamond_pid = ctx->kdamond->pid; + return 0; +} + +static struct delayed_work damon_lru_sort_timer; +static void damon_lru_sort_timer_fn(struct work_struct *work) +{ + static bool last_enabled; + bool now_enabled; + + now_enabled = enabled; + if (last_enabled != now_enabled) { + if (!damon_lru_sort_turn(now_enabled)) + last_enabled = now_enabled; + else + enabled = last_enabled; + } +} +static DECLARE_DELAYED_WORK(damon_lru_sort_timer, damon_lru_sort_timer_fn); + +static bool damon_lru_sort_initialized; + +static int damon_lru_sort_enabled_store(const char *val, + const struct kernel_param *kp) +{ + int rc = param_set_bool(val, kp); + + if (rc < 0) + return rc; + + if (!damon_lru_sort_initialized) + return rc; + + schedule_delayed_work(&damon_lru_sort_timer, 0); + + return 0; +} + +static const struct kernel_param_ops enabled_param_ops = { + .set = damon_lru_sort_enabled_store, + .get = param_get_bool, +}; + +module_param_cb(enabled, &enabled_param_ops, &enabled, 0600); +MODULE_PARM_DESC(enabled, + "Enable or disable DAMON_LRU_SORT (default: disabled)"); + +static int damon_lru_sort_handle_commit_inputs(void) +{ + int err; + + if (!commit_inputs) + return 0; + + err = damon_lru_sort_apply_parameters(); + commit_inputs = false; + return err; +} + +static int damon_lru_sort_after_aggregation(struct damon_ctx *c) +{ + struct damos *s; + + /* update the stats parameter */ + damon_for_each_scheme(s, c) { + if (s->action == DAMOS_LRU_PRIO) + damon_lru_sort_hot_stat = s->stat; + else if (s->action == DAMOS_LRU_DEPRIO) + damon_lru_sort_cold_stat = s->stat; + } + + return damon_lru_sort_handle_commit_inputs(); +} + +static int damon_lru_sort_after_wmarks_check(struct damon_ctx *c) +{ + return damon_lru_sort_handle_commit_inputs(); +} + +static int __init damon_lru_sort_init(void) +{ + ctx = damon_new_ctx(); + if (!ctx) + return -ENOMEM; + + if (damon_select_ops(ctx, DAMON_OPS_PADDR)) { + damon_destroy_ctx(ctx); + return -EINVAL; + } + + ctx->callback.after_wmarks_check = damon_lru_sort_after_wmarks_check; + ctx->callback.after_aggregation = damon_lru_sort_after_aggregation; + + target = damon_new_target(); + if (!target) { + damon_destroy_ctx(ctx); + return -ENOMEM; + } + damon_add_target(ctx, target); + + schedule_delayed_work(&damon_lru_sort_timer, 0); + + damon_lru_sort_initialized = true; + return 0; +} + +module_init(damon_lru_sort_init); diff --git a/mm/damon/modules-common.h b/mm/damon/modules-common.h new file mode 100644 index 000000000..5a4921851 --- /dev/null +++ b/mm/damon/modules-common.h @@ -0,0 +1,46 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Common Primitives for DAMON Modules + * + * Author: SeongJae Park <sj@kernel.org> + */ + +#include <linux/moduleparam.h> + +#define DEFINE_DAMON_MODULES_MON_ATTRS_PARAMS(attrs) \ + module_param_named(sample_interval, attrs.sample_interval, \ + ulong, 0600); \ + module_param_named(aggr_interval, attrs.aggr_interval, ulong, \ + 0600); \ + module_param_named(min_nr_regions, attrs.min_nr_regions, ulong, \ + 0600); \ + module_param_named(max_nr_regions, attrs.max_nr_regions, ulong, \ + 0600); + +#define DEFINE_DAMON_MODULES_DAMOS_TIME_QUOTA(quota) \ + module_param_named(quota_ms, quota.ms, ulong, 0600); \ + module_param_named(quota_reset_interval_ms, \ + quota.reset_interval, ulong, 0600); + +#define DEFINE_DAMON_MODULES_DAMOS_QUOTAS(quota) \ + DEFINE_DAMON_MODULES_DAMOS_TIME_QUOTA(quota) \ + module_param_named(quota_sz, quota.sz, ulong, 0600); + +#define DEFINE_DAMON_MODULES_WMARKS_PARAMS(wmarks) \ + module_param_named(wmarks_interval, wmarks.interval, ulong, \ + 0600); \ + module_param_named(wmarks_high, wmarks.high, ulong, 0600); \ + module_param_named(wmarks_mid, wmarks.mid, ulong, 0600); \ + module_param_named(wmarks_low, wmarks.low, ulong, 0600); + +#define DEFINE_DAMON_MODULES_DAMOS_STATS_PARAMS(stat, try_name, \ + succ_name, qt_exceed_name) \ + module_param_named(nr_##try_name, stat.nr_tried, ulong, 0400); \ + module_param_named(bytes_##try_name, stat.sz_tried, ulong, \ + 0400); \ + module_param_named(nr_##succ_name, stat.nr_applied, ulong, \ + 0400); \ + module_param_named(bytes_##succ_name, stat.sz_applied, ulong, \ + 0400); \ + module_param_named(nr_##qt_exceed_name, stat.qt_exceeds, ulong, \ + 0400); diff --git a/mm/damon/ops-common.c b/mm/damon/ops-common.c new file mode 100644 index 000000000..0b75a8d5c --- /dev/null +++ b/mm/damon/ops-common.c @@ -0,0 +1,135 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Common Primitives for Data Access Monitoring + * + * Author: SeongJae Park <sj@kernel.org> + */ + +#include <linux/mmu_notifier.h> +#include <linux/page_idle.h> +#include <linux/pagemap.h> +#include <linux/rmap.h> + +#include "ops-common.h" + +/* + * Get an online page for a pfn if it's in the LRU list. Otherwise, returns + * NULL. + * + * The body of this function is stolen from the 'page_idle_get_page()'. We + * steal rather than reuse it because the code is quite simple. + */ +struct page *damon_get_page(unsigned long pfn) +{ + struct page *page = pfn_to_online_page(pfn); + + if (!page || !PageLRU(page) || !get_page_unless_zero(page)) + return NULL; + + if (unlikely(!PageLRU(page))) { + put_page(page); + page = NULL; + } + return page; +} + +void damon_ptep_mkold(pte_t *pte, struct vm_area_struct *vma, unsigned long addr) +{ + bool referenced = false; + struct page *page = damon_get_page(pte_pfn(*pte)); + + if (!page) + return; + + if (ptep_test_and_clear_young(vma, addr, pte)) + referenced = true; + +#ifdef CONFIG_MMU_NOTIFIER + if (mmu_notifier_clear_young(vma->vm_mm, addr, addr + PAGE_SIZE)) + referenced = true; +#endif /* CONFIG_MMU_NOTIFIER */ + + if (referenced) + set_page_young(page); + + set_page_idle(page); + put_page(page); +} + +void damon_pmdp_mkold(pmd_t *pmd, struct vm_area_struct *vma, unsigned long addr) +{ +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + bool referenced = false; + struct page *page = damon_get_page(pmd_pfn(*pmd)); + + if (!page) + return; + + if (pmdp_test_and_clear_young(vma, addr, pmd)) + referenced = true; + +#ifdef CONFIG_MMU_NOTIFIER + if (mmu_notifier_clear_young(vma->vm_mm, addr, addr + HPAGE_PMD_SIZE)) + referenced = true; +#endif /* CONFIG_MMU_NOTIFIER */ + + if (referenced) + set_page_young(page); + + set_page_idle(page); + put_page(page); +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ +} + +#define DAMON_MAX_SUBSCORE (100) +#define DAMON_MAX_AGE_IN_LOG (32) + +int damon_hot_score(struct damon_ctx *c, struct damon_region *r, + struct damos *s) +{ + int freq_subscore; + unsigned int age_in_sec; + int age_in_log, age_subscore; + unsigned int freq_weight = s->quota.weight_nr_accesses; + unsigned int age_weight = s->quota.weight_age; + int hotness; + + freq_subscore = r->nr_accesses * DAMON_MAX_SUBSCORE / + damon_max_nr_accesses(&c->attrs); + + age_in_sec = (unsigned long)r->age * c->attrs.aggr_interval / 1000000; + for (age_in_log = 0; age_in_log < DAMON_MAX_AGE_IN_LOG && age_in_sec; + age_in_log++, age_in_sec >>= 1) + ; + + /* If frequency is 0, higher age means it's colder */ + if (freq_subscore == 0) + age_in_log *= -1; + + /* + * Now age_in_log is in [-DAMON_MAX_AGE_IN_LOG, DAMON_MAX_AGE_IN_LOG]. + * Scale it to be in [0, 100] and set it as age subscore. + */ + age_in_log += DAMON_MAX_AGE_IN_LOG; + age_subscore = age_in_log * DAMON_MAX_SUBSCORE / + DAMON_MAX_AGE_IN_LOG / 2; + + hotness = (freq_weight * freq_subscore + age_weight * age_subscore); + if (freq_weight + age_weight) + hotness /= freq_weight + age_weight; + /* + * Transform it to fit in [0, DAMOS_MAX_SCORE] + */ + hotness = hotness * DAMOS_MAX_SCORE / DAMON_MAX_SUBSCORE; + + return hotness; +} + +int damon_cold_score(struct damon_ctx *c, struct damon_region *r, + struct damos *s) +{ + int hotness = damon_hot_score(c, r, s); + + /* Return coldness of the region */ + return DAMOS_MAX_SCORE - hotness; +} diff --git a/mm/damon/ops-common.h b/mm/damon/ops-common.h new file mode 100644 index 000000000..e062a8874 --- /dev/null +++ b/mm/damon/ops-common.h @@ -0,0 +1,18 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Common Primitives for Data Access Monitoring + * + * Author: SeongJae Park <sj@kernel.org> + */ + +#include <linux/damon.h> + +struct page *damon_get_page(unsigned long pfn); + +void damon_ptep_mkold(pte_t *pte, struct vm_area_struct *vma, unsigned long addr); +void damon_pmdp_mkold(pmd_t *pmd, struct vm_area_struct *vma, unsigned long addr); + +int damon_cold_score(struct damon_ctx *c, struct damon_region *r, + struct damos *s); +int damon_hot_score(struct damon_ctx *c, struct damon_region *r, + struct damos *s); diff --git a/mm/damon/paddr.c b/mm/damon/paddr.c new file mode 100644 index 000000000..7bc8d79c7 --- /dev/null +++ b/mm/damon/paddr.c @@ -0,0 +1,319 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DAMON Primitives for The Physical Address Space + * + * Author: SeongJae Park <sj@kernel.org> + */ + +#define pr_fmt(fmt) "damon-pa: " fmt + +#include <linux/mmu_notifier.h> +#include <linux/page_idle.h> +#include <linux/pagemap.h> +#include <linux/rmap.h> +#include <linux/swap.h> + +#include "../internal.h" +#include "ops-common.h" + +static bool __damon_pa_mkold(struct folio *folio, struct vm_area_struct *vma, + unsigned long addr, void *arg) +{ + DEFINE_FOLIO_VMA_WALK(pvmw, folio, vma, addr, 0); + + while (page_vma_mapped_walk(&pvmw)) { + addr = pvmw.address; + if (pvmw.pte) + damon_ptep_mkold(pvmw.pte, vma, addr); + else + damon_pmdp_mkold(pvmw.pmd, vma, addr); + } + return true; +} + +static void damon_pa_mkold(unsigned long paddr) +{ + struct folio *folio; + struct page *page = damon_get_page(PHYS_PFN(paddr)); + struct rmap_walk_control rwc = { + .rmap_one = __damon_pa_mkold, + .anon_lock = folio_lock_anon_vma_read, + }; + bool need_lock; + + if (!page) + return; + folio = page_folio(page); + + if (!folio_mapped(folio) || !folio_raw_mapping(folio)) { + folio_set_idle(folio); + goto out; + } + + need_lock = !folio_test_anon(folio) || folio_test_ksm(folio); + if (need_lock && !folio_trylock(folio)) + goto out; + + rmap_walk(folio, &rwc); + + if (need_lock) + folio_unlock(folio); + +out: + folio_put(folio); +} + +static void __damon_pa_prepare_access_check(struct damon_region *r) +{ + r->sampling_addr = damon_rand(r->ar.start, r->ar.end); + + damon_pa_mkold(r->sampling_addr); +} + +static void damon_pa_prepare_access_checks(struct damon_ctx *ctx) +{ + struct damon_target *t; + struct damon_region *r; + + damon_for_each_target(t, ctx) { + damon_for_each_region(r, t) + __damon_pa_prepare_access_check(r); + } +} + +struct damon_pa_access_chk_result { + unsigned long page_sz; + bool accessed; +}; + +static bool __damon_pa_young(struct folio *folio, struct vm_area_struct *vma, + unsigned long addr, void *arg) +{ + struct damon_pa_access_chk_result *result = arg; + DEFINE_FOLIO_VMA_WALK(pvmw, folio, vma, addr, 0); + + result->accessed = false; + result->page_sz = PAGE_SIZE; + while (page_vma_mapped_walk(&pvmw)) { + addr = pvmw.address; + if (pvmw.pte) { + result->accessed = pte_young(*pvmw.pte) || + !folio_test_idle(folio) || + mmu_notifier_test_young(vma->vm_mm, addr); + } else { +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + result->accessed = pmd_young(*pvmw.pmd) || + !folio_test_idle(folio) || + mmu_notifier_test_young(vma->vm_mm, addr); + result->page_sz = HPAGE_PMD_SIZE; +#else + WARN_ON_ONCE(1); +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ + } + if (result->accessed) { + page_vma_mapped_walk_done(&pvmw); + break; + } + } + + /* If accessed, stop walking */ + return !result->accessed; +} + +static bool damon_pa_young(unsigned long paddr, unsigned long *page_sz) +{ + struct folio *folio; + struct page *page = damon_get_page(PHYS_PFN(paddr)); + struct damon_pa_access_chk_result result = { + .page_sz = PAGE_SIZE, + .accessed = false, + }; + struct rmap_walk_control rwc = { + .arg = &result, + .rmap_one = __damon_pa_young, + .anon_lock = folio_lock_anon_vma_read, + }; + bool need_lock; + + if (!page) + return false; + folio = page_folio(page); + + if (!folio_mapped(folio) || !folio_raw_mapping(folio)) { + if (folio_test_idle(folio)) + result.accessed = false; + else + result.accessed = true; + folio_put(folio); + goto out; + } + + need_lock = !folio_test_anon(folio) || folio_test_ksm(folio); + if (need_lock && !folio_trylock(folio)) { + folio_put(folio); + return false; + } + + rmap_walk(folio, &rwc); + + if (need_lock) + folio_unlock(folio); + folio_put(folio); + +out: + *page_sz = result.page_sz; + return result.accessed; +} + +static void __damon_pa_check_access(struct damon_region *r) +{ + static unsigned long last_addr; + static unsigned long last_page_sz = PAGE_SIZE; + static bool last_accessed; + + /* If the region is in the last checked page, reuse the result */ + if (ALIGN_DOWN(last_addr, last_page_sz) == + ALIGN_DOWN(r->sampling_addr, last_page_sz)) { + if (last_accessed) + r->nr_accesses++; + return; + } + + last_accessed = damon_pa_young(r->sampling_addr, &last_page_sz); + if (last_accessed) + r->nr_accesses++; + + last_addr = r->sampling_addr; +} + +static unsigned int damon_pa_check_accesses(struct damon_ctx *ctx) +{ + struct damon_target *t; + struct damon_region *r; + unsigned int max_nr_accesses = 0; + + damon_for_each_target(t, ctx) { + damon_for_each_region(r, t) { + __damon_pa_check_access(r); + max_nr_accesses = max(r->nr_accesses, max_nr_accesses); + } + } + + return max_nr_accesses; +} + +static unsigned long damon_pa_pageout(struct damon_region *r) +{ + unsigned long addr, applied; + LIST_HEAD(page_list); + + for (addr = r->ar.start; addr < r->ar.end; addr += PAGE_SIZE) { + struct page *page = damon_get_page(PHYS_PFN(addr)); + + if (!page) + continue; + + ClearPageReferenced(page); + test_and_clear_page_young(page); + if (isolate_lru_page(page)) { + put_page(page); + continue; + } + if (PageUnevictable(page)) + putback_lru_page(page); + else + list_add(&page->lru, &page_list); + put_page(page); + } + applied = reclaim_pages(&page_list); + cond_resched(); + return applied * PAGE_SIZE; +} + +static inline unsigned long damon_pa_mark_accessed_or_deactivate( + struct damon_region *r, bool mark_accessed) +{ + unsigned long addr, applied = 0; + + for (addr = r->ar.start; addr < r->ar.end; addr += PAGE_SIZE) { + struct page *page = damon_get_page(PHYS_PFN(addr)); + + if (!page) + continue; + if (mark_accessed) + mark_page_accessed(page); + else + deactivate_page(page); + put_page(page); + applied++; + } + return applied * PAGE_SIZE; +} + +static unsigned long damon_pa_mark_accessed(struct damon_region *r) +{ + return damon_pa_mark_accessed_or_deactivate(r, true); +} + +static unsigned long damon_pa_deactivate_pages(struct damon_region *r) +{ + return damon_pa_mark_accessed_or_deactivate(r, false); +} + +static unsigned long damon_pa_apply_scheme(struct damon_ctx *ctx, + struct damon_target *t, struct damon_region *r, + struct damos *scheme) +{ + switch (scheme->action) { + case DAMOS_PAGEOUT: + return damon_pa_pageout(r); + case DAMOS_LRU_PRIO: + return damon_pa_mark_accessed(r); + case DAMOS_LRU_DEPRIO: + return damon_pa_deactivate_pages(r); + case DAMOS_STAT: + break; + default: + /* DAMOS actions that not yet supported by 'paddr'. */ + break; + } + return 0; +} + +static int damon_pa_scheme_score(struct damon_ctx *context, + struct damon_target *t, struct damon_region *r, + struct damos *scheme) +{ + switch (scheme->action) { + case DAMOS_PAGEOUT: + return damon_cold_score(context, r, scheme); + case DAMOS_LRU_PRIO: + return damon_hot_score(context, r, scheme); + case DAMOS_LRU_DEPRIO: + return damon_cold_score(context, r, scheme); + default: + break; + } + + return DAMOS_MAX_SCORE; +} + +static int __init damon_pa_initcall(void) +{ + struct damon_operations ops = { + .id = DAMON_OPS_PADDR, + .init = NULL, + .update = NULL, + .prepare_access_checks = damon_pa_prepare_access_checks, + .check_accesses = damon_pa_check_accesses, + .reset_aggregated = NULL, + .target_valid = NULL, + .cleanup = NULL, + .apply_scheme = damon_pa_apply_scheme, + .get_scheme_score = damon_pa_scheme_score, + }; + + return damon_register_ops(&ops); +}; + +subsys_initcall(damon_pa_initcall); diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c new file mode 100644 index 000000000..162c9b1ca --- /dev/null +++ b/mm/damon/reclaim.c @@ -0,0 +1,284 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DAMON-based page reclamation + * + * Author: SeongJae Park <sj@kernel.org> + */ + +#define pr_fmt(fmt) "damon-reclaim: " fmt + +#include <linux/damon.h> +#include <linux/ioport.h> +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/workqueue.h> + +#include "modules-common.h" + +#ifdef MODULE_PARAM_PREFIX +#undef MODULE_PARAM_PREFIX +#endif +#define MODULE_PARAM_PREFIX "damon_reclaim." + +/* + * Enable or disable DAMON_RECLAIM. + * + * You can enable DAMON_RCLAIM by setting the value of this parameter as ``Y``. + * Setting it as ``N`` disables DAMON_RECLAIM. Note that DAMON_RECLAIM could + * do no real monitoring and reclamation due to the watermarks-based activation + * condition. Refer to below descriptions for the watermarks parameter for + * this. + */ +static bool enabled __read_mostly; + +/* + * Make DAMON_RECLAIM reads the input parameters again, except ``enabled``. + * + * Input parameters that updated while DAMON_RECLAIM is running are not applied + * by default. Once this parameter is set as ``Y``, DAMON_RECLAIM reads values + * of parametrs except ``enabled`` again. Once the re-reading is done, this + * parameter is set as ``N``. If invalid parameters are found while the + * re-reading, DAMON_RECLAIM will be disabled. + */ +static bool commit_inputs __read_mostly; +module_param(commit_inputs, bool, 0600); + +/* + * Time threshold for cold memory regions identification in microseconds. + * + * If a memory region is not accessed for this or longer time, DAMON_RECLAIM + * identifies the region as cold, and reclaims. 120 seconds by default. + */ +static unsigned long min_age __read_mostly = 120000000; +module_param(min_age, ulong, 0600); + +static struct damos_quota damon_reclaim_quota = { + /* use up to 10 ms time, reclaim up to 128 MiB per 1 sec by default */ + .ms = 10, + .sz = 128 * 1024 * 1024, + .reset_interval = 1000, + /* Within the quota, page out older regions first. */ + .weight_sz = 0, + .weight_nr_accesses = 0, + .weight_age = 1 +}; +DEFINE_DAMON_MODULES_DAMOS_QUOTAS(damon_reclaim_quota); + +static struct damos_watermarks damon_reclaim_wmarks = { + .metric = DAMOS_WMARK_FREE_MEM_RATE, + .interval = 5000000, /* 5 seconds */ + .high = 500, /* 50 percent */ + .mid = 400, /* 40 percent */ + .low = 200, /* 20 percent */ +}; +DEFINE_DAMON_MODULES_WMARKS_PARAMS(damon_reclaim_wmarks); + +static struct damon_attrs damon_reclaim_mon_attrs = { + .sample_interval = 5000, /* 5 ms */ + .aggr_interval = 100000, /* 100 ms */ + .ops_update_interval = 0, + .min_nr_regions = 10, + .max_nr_regions = 1000, +}; +DEFINE_DAMON_MODULES_MON_ATTRS_PARAMS(damon_reclaim_mon_attrs); + +/* + * Start of the target memory region in physical address. + * + * The start physical address of memory region that DAMON_RECLAIM will do work + * against. By default, biggest System RAM is used as the region. + */ +static unsigned long monitor_region_start __read_mostly; +module_param(monitor_region_start, ulong, 0600); + +/* + * End of the target memory region in physical address. + * + * The end physical address of memory region that DAMON_RECLAIM will do work + * against. By default, biggest System RAM is used as the region. + */ +static unsigned long monitor_region_end __read_mostly; +module_param(monitor_region_end, ulong, 0600); + +/* + * PID of the DAMON thread + * + * If DAMON_RECLAIM is enabled, this becomes the PID of the worker thread. + * Else, -1. + */ +static int kdamond_pid __read_mostly = -1; +module_param(kdamond_pid, int, 0400); + +static struct damos_stat damon_reclaim_stat; +DEFINE_DAMON_MODULES_DAMOS_STATS_PARAMS(damon_reclaim_stat, + reclaim_tried_regions, reclaimed_regions, quota_exceeds); + +static struct damon_ctx *ctx; +static struct damon_target *target; + +static struct damos *damon_reclaim_new_scheme(void) +{ + struct damos_access_pattern pattern = { + /* Find regions having PAGE_SIZE or larger size */ + .min_sz_region = PAGE_SIZE, + .max_sz_region = ULONG_MAX, + /* and not accessed at all */ + .min_nr_accesses = 0, + .max_nr_accesses = 0, + /* for min_age or more micro-seconds */ + .min_age_region = min_age / + damon_reclaim_mon_attrs.aggr_interval, + .max_age_region = UINT_MAX, + }; + + return damon_new_scheme( + &pattern, + /* page out those, as soon as found */ + DAMOS_PAGEOUT, + /* under the quota. */ + &damon_reclaim_quota, + /* (De)activate this according to the watermarks. */ + &damon_reclaim_wmarks); +} + +static int damon_reclaim_apply_parameters(void) +{ + struct damos *scheme; + int err = 0; + + err = damon_set_attrs(ctx, &damon_reclaim_mon_attrs); + if (err) + return err; + + /* Will be freed by next 'damon_set_schemes()' below */ + scheme = damon_reclaim_new_scheme(); + if (!scheme) + return -ENOMEM; + damon_set_schemes(ctx, &scheme, 1); + + return damon_set_region_biggest_system_ram_default(target, + &monitor_region_start, + &monitor_region_end); +} + +static int damon_reclaim_turn(bool on) +{ + int err; + + if (!on) { + err = damon_stop(&ctx, 1); + if (!err) + kdamond_pid = -1; + return err; + } + + err = damon_reclaim_apply_parameters(); + if (err) + return err; + + err = damon_start(&ctx, 1, true); + if (err) + return err; + kdamond_pid = ctx->kdamond->pid; + return 0; +} + +static struct delayed_work damon_reclaim_timer; +static void damon_reclaim_timer_fn(struct work_struct *work) +{ + static bool last_enabled; + bool now_enabled; + + now_enabled = enabled; + if (last_enabled != now_enabled) { + if (!damon_reclaim_turn(now_enabled)) + last_enabled = now_enabled; + else + enabled = last_enabled; + } +} +static DECLARE_DELAYED_WORK(damon_reclaim_timer, damon_reclaim_timer_fn); + +static bool damon_reclaim_initialized; + +static int damon_reclaim_enabled_store(const char *val, + const struct kernel_param *kp) +{ + int rc = param_set_bool(val, kp); + + if (rc < 0) + return rc; + + /* system_wq might not initialized yet */ + if (!damon_reclaim_initialized) + return rc; + + schedule_delayed_work(&damon_reclaim_timer, 0); + return 0; +} + +static const struct kernel_param_ops enabled_param_ops = { + .set = damon_reclaim_enabled_store, + .get = param_get_bool, +}; + +module_param_cb(enabled, &enabled_param_ops, &enabled, 0600); +MODULE_PARM_DESC(enabled, + "Enable or disable DAMON_RECLAIM (default: disabled)"); + +static int damon_reclaim_handle_commit_inputs(void) +{ + int err; + + if (!commit_inputs) + return 0; + + err = damon_reclaim_apply_parameters(); + commit_inputs = false; + return err; +} + +static int damon_reclaim_after_aggregation(struct damon_ctx *c) +{ + struct damos *s; + + /* update the stats parameter */ + damon_for_each_scheme(s, c) + damon_reclaim_stat = s->stat; + + return damon_reclaim_handle_commit_inputs(); +} + +static int damon_reclaim_after_wmarks_check(struct damon_ctx *c) +{ + return damon_reclaim_handle_commit_inputs(); +} + +static int __init damon_reclaim_init(void) +{ + ctx = damon_new_ctx(); + if (!ctx) + return -ENOMEM; + + if (damon_select_ops(ctx, DAMON_OPS_PADDR)) { + damon_destroy_ctx(ctx); + return -EINVAL; + } + + ctx->callback.after_wmarks_check = damon_reclaim_after_wmarks_check; + ctx->callback.after_aggregation = damon_reclaim_after_aggregation; + + target = damon_new_target(); + if (!target) { + damon_destroy_ctx(ctx); + return -ENOMEM; + } + damon_add_target(ctx, target); + + schedule_delayed_work(&damon_reclaim_timer, 0); + + damon_reclaim_initialized = true; + return 0; +} + +module_init(damon_reclaim_init); diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c new file mode 100644 index 000000000..9ea21b6d2 --- /dev/null +++ b/mm/damon/sysfs.c @@ -0,0 +1,2909 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DAMON sysfs Interface + * + * Copyright (c) 2022 SeongJae Park <sj@kernel.org> + */ + +#include <linux/damon.h> +#include <linux/kobject.h> +#include <linux/pid.h> +#include <linux/sched.h> +#include <linux/slab.h> + +static DEFINE_MUTEX(damon_sysfs_lock); + +/* + * unsigned long range directory + */ + +struct damon_sysfs_ul_range { + struct kobject kobj; + unsigned long min; + unsigned long max; +}; + +static struct damon_sysfs_ul_range *damon_sysfs_ul_range_alloc( + unsigned long min, + unsigned long max) +{ + struct damon_sysfs_ul_range *range = kmalloc(sizeof(*range), + GFP_KERNEL); + + if (!range) + return NULL; + range->kobj = (struct kobject){}; + range->min = min; + range->max = max; + + return range; +} + +static ssize_t min_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_ul_range *range = container_of(kobj, + struct damon_sysfs_ul_range, kobj); + + return sysfs_emit(buf, "%lu\n", range->min); +} + +static ssize_t min_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct damon_sysfs_ul_range *range = container_of(kobj, + struct damon_sysfs_ul_range, kobj); + unsigned long min; + int err; + + err = kstrtoul(buf, 0, &min); + if (err) + return err; + + range->min = min; + return count; +} + +static ssize_t max_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_ul_range *range = container_of(kobj, + struct damon_sysfs_ul_range, kobj); + + return sysfs_emit(buf, "%lu\n", range->max); +} + +static ssize_t max_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct damon_sysfs_ul_range *range = container_of(kobj, + struct damon_sysfs_ul_range, kobj); + unsigned long max; + int err; + + err = kstrtoul(buf, 0, &max); + if (err) + return err; + + range->max = max; + return count; +} + +static void damon_sysfs_ul_range_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_ul_range, kobj)); +} + +static struct kobj_attribute damon_sysfs_ul_range_min_attr = + __ATTR_RW_MODE(min, 0600); + +static struct kobj_attribute damon_sysfs_ul_range_max_attr = + __ATTR_RW_MODE(max, 0600); + +static struct attribute *damon_sysfs_ul_range_attrs[] = { + &damon_sysfs_ul_range_min_attr.attr, + &damon_sysfs_ul_range_max_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_ul_range); + +static struct kobj_type damon_sysfs_ul_range_ktype = { + .release = damon_sysfs_ul_range_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_ul_range_groups, +}; + +/* + * schemes/stats directory + */ + +struct damon_sysfs_stats { + struct kobject kobj; + unsigned long nr_tried; + unsigned long sz_tried; + unsigned long nr_applied; + unsigned long sz_applied; + unsigned long qt_exceeds; +}; + +static struct damon_sysfs_stats *damon_sysfs_stats_alloc(void) +{ + return kzalloc(sizeof(struct damon_sysfs_stats), GFP_KERNEL); +} + +static ssize_t nr_tried_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_stats *stats = container_of(kobj, + struct damon_sysfs_stats, kobj); + + return sysfs_emit(buf, "%lu\n", stats->nr_tried); +} + +static ssize_t sz_tried_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_stats *stats = container_of(kobj, + struct damon_sysfs_stats, kobj); + + return sysfs_emit(buf, "%lu\n", stats->sz_tried); +} + +static ssize_t nr_applied_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_stats *stats = container_of(kobj, + struct damon_sysfs_stats, kobj); + + return sysfs_emit(buf, "%lu\n", stats->nr_applied); +} + +static ssize_t sz_applied_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_stats *stats = container_of(kobj, + struct damon_sysfs_stats, kobj); + + return sysfs_emit(buf, "%lu\n", stats->sz_applied); +} + +static ssize_t qt_exceeds_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_stats *stats = container_of(kobj, + struct damon_sysfs_stats, kobj); + + return sysfs_emit(buf, "%lu\n", stats->qt_exceeds); +} + +static void damon_sysfs_stats_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_stats, kobj)); +} + +static struct kobj_attribute damon_sysfs_stats_nr_tried_attr = + __ATTR_RO_MODE(nr_tried, 0400); + +static struct kobj_attribute damon_sysfs_stats_sz_tried_attr = + __ATTR_RO_MODE(sz_tried, 0400); + +static struct kobj_attribute damon_sysfs_stats_nr_applied_attr = + __ATTR_RO_MODE(nr_applied, 0400); + +static struct kobj_attribute damon_sysfs_stats_sz_applied_attr = + __ATTR_RO_MODE(sz_applied, 0400); + +static struct kobj_attribute damon_sysfs_stats_qt_exceeds_attr = + __ATTR_RO_MODE(qt_exceeds, 0400); + +static struct attribute *damon_sysfs_stats_attrs[] = { + &damon_sysfs_stats_nr_tried_attr.attr, + &damon_sysfs_stats_sz_tried_attr.attr, + &damon_sysfs_stats_nr_applied_attr.attr, + &damon_sysfs_stats_sz_applied_attr.attr, + &damon_sysfs_stats_qt_exceeds_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_stats); + +static struct kobj_type damon_sysfs_stats_ktype = { + .release = damon_sysfs_stats_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_stats_groups, +}; + +/* + * watermarks directory + */ + +struct damon_sysfs_watermarks { + struct kobject kobj; + enum damos_wmark_metric metric; + unsigned long interval_us; + unsigned long high; + unsigned long mid; + unsigned long low; +}; + +static struct damon_sysfs_watermarks *damon_sysfs_watermarks_alloc( + enum damos_wmark_metric metric, unsigned long interval_us, + unsigned long high, unsigned long mid, unsigned long low) +{ + struct damon_sysfs_watermarks *watermarks = kmalloc( + sizeof(*watermarks), GFP_KERNEL); + + if (!watermarks) + return NULL; + watermarks->kobj = (struct kobject){}; + watermarks->metric = metric; + watermarks->interval_us = interval_us; + watermarks->high = high; + watermarks->mid = mid; + watermarks->low = low; + return watermarks; +} + +/* Should match with enum damos_wmark_metric */ +static const char * const damon_sysfs_wmark_metric_strs[] = { + "none", + "free_mem_rate", +}; + +static ssize_t metric_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_watermarks *watermarks = container_of(kobj, + struct damon_sysfs_watermarks, kobj); + + return sysfs_emit(buf, "%s\n", + damon_sysfs_wmark_metric_strs[watermarks->metric]); +} + +static ssize_t metric_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct damon_sysfs_watermarks *watermarks = container_of(kobj, + struct damon_sysfs_watermarks, kobj); + enum damos_wmark_metric metric; + + for (metric = 0; metric < NR_DAMOS_WMARK_METRICS; metric++) { + if (sysfs_streq(buf, damon_sysfs_wmark_metric_strs[metric])) { + watermarks->metric = metric; + return count; + } + } + return -EINVAL; +} + +static ssize_t interval_us_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_watermarks *watermarks = container_of(kobj, + struct damon_sysfs_watermarks, kobj); + + return sysfs_emit(buf, "%lu\n", watermarks->interval_us); +} + +static ssize_t interval_us_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_watermarks *watermarks = container_of(kobj, + struct damon_sysfs_watermarks, kobj); + int err = kstrtoul(buf, 0, &watermarks->interval_us); + + return err ? err : count; +} + +static ssize_t high_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_watermarks *watermarks = container_of(kobj, + struct damon_sysfs_watermarks, kobj); + + return sysfs_emit(buf, "%lu\n", watermarks->high); +} + +static ssize_t high_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_watermarks *watermarks = container_of(kobj, + struct damon_sysfs_watermarks, kobj); + int err = kstrtoul(buf, 0, &watermarks->high); + + return err ? err : count; +} + +static ssize_t mid_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_watermarks *watermarks = container_of(kobj, + struct damon_sysfs_watermarks, kobj); + + return sysfs_emit(buf, "%lu\n", watermarks->mid); +} + +static ssize_t mid_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_watermarks *watermarks = container_of(kobj, + struct damon_sysfs_watermarks, kobj); + int err = kstrtoul(buf, 0, &watermarks->mid); + + return err ? err : count; +} + +static ssize_t low_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_watermarks *watermarks = container_of(kobj, + struct damon_sysfs_watermarks, kobj); + + return sysfs_emit(buf, "%lu\n", watermarks->low); +} + +static ssize_t low_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_watermarks *watermarks = container_of(kobj, + struct damon_sysfs_watermarks, kobj); + int err = kstrtoul(buf, 0, &watermarks->low); + + return err ? err : count; +} + +static void damon_sysfs_watermarks_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_watermarks, kobj)); +} + +static struct kobj_attribute damon_sysfs_watermarks_metric_attr = + __ATTR_RW_MODE(metric, 0600); + +static struct kobj_attribute damon_sysfs_watermarks_interval_us_attr = + __ATTR_RW_MODE(interval_us, 0600); + +static struct kobj_attribute damon_sysfs_watermarks_high_attr = + __ATTR_RW_MODE(high, 0600); + +static struct kobj_attribute damon_sysfs_watermarks_mid_attr = + __ATTR_RW_MODE(mid, 0600); + +static struct kobj_attribute damon_sysfs_watermarks_low_attr = + __ATTR_RW_MODE(low, 0600); + +static struct attribute *damon_sysfs_watermarks_attrs[] = { + &damon_sysfs_watermarks_metric_attr.attr, + &damon_sysfs_watermarks_interval_us_attr.attr, + &damon_sysfs_watermarks_high_attr.attr, + &damon_sysfs_watermarks_mid_attr.attr, + &damon_sysfs_watermarks_low_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_watermarks); + +static struct kobj_type damon_sysfs_watermarks_ktype = { + .release = damon_sysfs_watermarks_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_watermarks_groups, +}; + +/* + * scheme/weights directory + */ + +struct damon_sysfs_weights { + struct kobject kobj; + unsigned int sz; + unsigned int nr_accesses; + unsigned int age; +}; + +static struct damon_sysfs_weights *damon_sysfs_weights_alloc(unsigned int sz, + unsigned int nr_accesses, unsigned int age) +{ + struct damon_sysfs_weights *weights = kmalloc(sizeof(*weights), + GFP_KERNEL); + + if (!weights) + return NULL; + weights->kobj = (struct kobject){}; + weights->sz = sz; + weights->nr_accesses = nr_accesses; + weights->age = age; + return weights; +} + +static ssize_t sz_permil_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_weights *weights = container_of(kobj, + struct damon_sysfs_weights, kobj); + + return sysfs_emit(buf, "%u\n", weights->sz); +} + +static ssize_t sz_permil_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_weights *weights = container_of(kobj, + struct damon_sysfs_weights, kobj); + int err = kstrtouint(buf, 0, &weights->sz); + + return err ? err : count; +} + +static ssize_t nr_accesses_permil_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_weights *weights = container_of(kobj, + struct damon_sysfs_weights, kobj); + + return sysfs_emit(buf, "%u\n", weights->nr_accesses); +} + +static ssize_t nr_accesses_permil_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_weights *weights = container_of(kobj, + struct damon_sysfs_weights, kobj); + int err = kstrtouint(buf, 0, &weights->nr_accesses); + + return err ? err : count; +} + +static ssize_t age_permil_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_weights *weights = container_of(kobj, + struct damon_sysfs_weights, kobj); + + return sysfs_emit(buf, "%u\n", weights->age); +} + +static ssize_t age_permil_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_weights *weights = container_of(kobj, + struct damon_sysfs_weights, kobj); + int err = kstrtouint(buf, 0, &weights->age); + + return err ? err : count; +} + +static void damon_sysfs_weights_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_weights, kobj)); +} + +static struct kobj_attribute damon_sysfs_weights_sz_attr = + __ATTR_RW_MODE(sz_permil, 0600); + +static struct kobj_attribute damon_sysfs_weights_nr_accesses_attr = + __ATTR_RW_MODE(nr_accesses_permil, 0600); + +static struct kobj_attribute damon_sysfs_weights_age_attr = + __ATTR_RW_MODE(age_permil, 0600); + +static struct attribute *damon_sysfs_weights_attrs[] = { + &damon_sysfs_weights_sz_attr.attr, + &damon_sysfs_weights_nr_accesses_attr.attr, + &damon_sysfs_weights_age_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_weights); + +static struct kobj_type damon_sysfs_weights_ktype = { + .release = damon_sysfs_weights_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_weights_groups, +}; + +/* + * quotas directory + */ + +struct damon_sysfs_quotas { + struct kobject kobj; + struct damon_sysfs_weights *weights; + unsigned long ms; + unsigned long sz; + unsigned long reset_interval_ms; +}; + +static struct damon_sysfs_quotas *damon_sysfs_quotas_alloc(void) +{ + return kzalloc(sizeof(struct damon_sysfs_quotas), GFP_KERNEL); +} + +static int damon_sysfs_quotas_add_dirs(struct damon_sysfs_quotas *quotas) +{ + struct damon_sysfs_weights *weights; + int err; + + weights = damon_sysfs_weights_alloc(0, 0, 0); + if (!weights) + return -ENOMEM; + + err = kobject_init_and_add(&weights->kobj, &damon_sysfs_weights_ktype, + "as->kobj, "weights"); + if (err) + kobject_put(&weights->kobj); + else + quotas->weights = weights; + return err; +} + +static void damon_sysfs_quotas_rm_dirs(struct damon_sysfs_quotas *quotas) +{ + kobject_put("as->weights->kobj); +} + +static ssize_t ms_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_quotas *quotas = container_of(kobj, + struct damon_sysfs_quotas, kobj); + + return sysfs_emit(buf, "%lu\n", quotas->ms); +} + +static ssize_t ms_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct damon_sysfs_quotas *quotas = container_of(kobj, + struct damon_sysfs_quotas, kobj); + int err = kstrtoul(buf, 0, "as->ms); + + if (err) + return -EINVAL; + return count; +} + +static ssize_t bytes_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_quotas *quotas = container_of(kobj, + struct damon_sysfs_quotas, kobj); + + return sysfs_emit(buf, "%lu\n", quotas->sz); +} + +static ssize_t bytes_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_quotas *quotas = container_of(kobj, + struct damon_sysfs_quotas, kobj); + int err = kstrtoul(buf, 0, "as->sz); + + if (err) + return -EINVAL; + return count; +} + +static ssize_t reset_interval_ms_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_quotas *quotas = container_of(kobj, + struct damon_sysfs_quotas, kobj); + + return sysfs_emit(buf, "%lu\n", quotas->reset_interval_ms); +} + +static ssize_t reset_interval_ms_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_quotas *quotas = container_of(kobj, + struct damon_sysfs_quotas, kobj); + int err = kstrtoul(buf, 0, "as->reset_interval_ms); + + if (err) + return -EINVAL; + return count; +} + +static void damon_sysfs_quotas_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_quotas, kobj)); +} + +static struct kobj_attribute damon_sysfs_quotas_ms_attr = + __ATTR_RW_MODE(ms, 0600); + +static struct kobj_attribute damon_sysfs_quotas_sz_attr = + __ATTR_RW_MODE(bytes, 0600); + +static struct kobj_attribute damon_sysfs_quotas_reset_interval_ms_attr = + __ATTR_RW_MODE(reset_interval_ms, 0600); + +static struct attribute *damon_sysfs_quotas_attrs[] = { + &damon_sysfs_quotas_ms_attr.attr, + &damon_sysfs_quotas_sz_attr.attr, + &damon_sysfs_quotas_reset_interval_ms_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_quotas); + +static struct kobj_type damon_sysfs_quotas_ktype = { + .release = damon_sysfs_quotas_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_quotas_groups, +}; + +/* + * access_pattern directory + */ + +struct damon_sysfs_access_pattern { + struct kobject kobj; + struct damon_sysfs_ul_range *sz; + struct damon_sysfs_ul_range *nr_accesses; + struct damon_sysfs_ul_range *age; +}; + +static +struct damon_sysfs_access_pattern *damon_sysfs_access_pattern_alloc(void) +{ + struct damon_sysfs_access_pattern *access_pattern = + kmalloc(sizeof(*access_pattern), GFP_KERNEL); + + if (!access_pattern) + return NULL; + access_pattern->kobj = (struct kobject){}; + return access_pattern; +} + +static int damon_sysfs_access_pattern_add_range_dir( + struct damon_sysfs_access_pattern *access_pattern, + struct damon_sysfs_ul_range **range_dir_ptr, + char *name) +{ + struct damon_sysfs_ul_range *range = damon_sysfs_ul_range_alloc(0, 0); + int err; + + if (!range) + return -ENOMEM; + err = kobject_init_and_add(&range->kobj, &damon_sysfs_ul_range_ktype, + &access_pattern->kobj, name); + if (err) + kobject_put(&range->kobj); + else + *range_dir_ptr = range; + return err; +} + +static int damon_sysfs_access_pattern_add_dirs( + struct damon_sysfs_access_pattern *access_pattern) +{ + int err; + + err = damon_sysfs_access_pattern_add_range_dir(access_pattern, + &access_pattern->sz, "sz"); + if (err) + goto put_sz_out; + + err = damon_sysfs_access_pattern_add_range_dir(access_pattern, + &access_pattern->nr_accesses, "nr_accesses"); + if (err) + goto put_nr_accesses_sz_out; + + err = damon_sysfs_access_pattern_add_range_dir(access_pattern, + &access_pattern->age, "age"); + if (err) + goto put_age_nr_accesses_sz_out; + return 0; + +put_age_nr_accesses_sz_out: + kobject_put(&access_pattern->age->kobj); + access_pattern->age = NULL; +put_nr_accesses_sz_out: + kobject_put(&access_pattern->nr_accesses->kobj); + access_pattern->nr_accesses = NULL; +put_sz_out: + kobject_put(&access_pattern->sz->kobj); + access_pattern->sz = NULL; + return err; +} + +static void damon_sysfs_access_pattern_rm_dirs( + struct damon_sysfs_access_pattern *access_pattern) +{ + kobject_put(&access_pattern->sz->kobj); + kobject_put(&access_pattern->nr_accesses->kobj); + kobject_put(&access_pattern->age->kobj); +} + +static void damon_sysfs_access_pattern_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_access_pattern, kobj)); +} + +static struct attribute *damon_sysfs_access_pattern_attrs[] = { + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_access_pattern); + +static struct kobj_type damon_sysfs_access_pattern_ktype = { + .release = damon_sysfs_access_pattern_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_access_pattern_groups, +}; + +/* + * scheme directory + */ + +struct damon_sysfs_scheme { + struct kobject kobj; + enum damos_action action; + struct damon_sysfs_access_pattern *access_pattern; + struct damon_sysfs_quotas *quotas; + struct damon_sysfs_watermarks *watermarks; + struct damon_sysfs_stats *stats; +}; + +/* This should match with enum damos_action */ +static const char * const damon_sysfs_damos_action_strs[] = { + "willneed", + "cold", + "pageout", + "hugepage", + "nohugepage", + "lru_prio", + "lru_deprio", + "stat", +}; + +static struct damon_sysfs_scheme *damon_sysfs_scheme_alloc( + enum damos_action action) +{ + struct damon_sysfs_scheme *scheme = kmalloc(sizeof(*scheme), + GFP_KERNEL); + + if (!scheme) + return NULL; + scheme->kobj = (struct kobject){}; + scheme->action = action; + return scheme; +} + +static int damon_sysfs_scheme_set_access_pattern( + struct damon_sysfs_scheme *scheme) +{ + struct damon_sysfs_access_pattern *access_pattern; + int err; + + access_pattern = damon_sysfs_access_pattern_alloc(); + if (!access_pattern) + return -ENOMEM; + err = kobject_init_and_add(&access_pattern->kobj, + &damon_sysfs_access_pattern_ktype, &scheme->kobj, + "access_pattern"); + if (err) + goto out; + err = damon_sysfs_access_pattern_add_dirs(access_pattern); + if (err) + goto out; + scheme->access_pattern = access_pattern; + return 0; + +out: + kobject_put(&access_pattern->kobj); + return err; +} + +static int damon_sysfs_scheme_set_quotas(struct damon_sysfs_scheme *scheme) +{ + struct damon_sysfs_quotas *quotas = damon_sysfs_quotas_alloc(); + int err; + + if (!quotas) + return -ENOMEM; + err = kobject_init_and_add("as->kobj, &damon_sysfs_quotas_ktype, + &scheme->kobj, "quotas"); + if (err) + goto out; + err = damon_sysfs_quotas_add_dirs(quotas); + if (err) + goto out; + scheme->quotas = quotas; + return 0; + +out: + kobject_put("as->kobj); + return err; +} + +static int damon_sysfs_scheme_set_watermarks(struct damon_sysfs_scheme *scheme) +{ + struct damon_sysfs_watermarks *watermarks = + damon_sysfs_watermarks_alloc(DAMOS_WMARK_NONE, 0, 0, 0, 0); + int err; + + if (!watermarks) + return -ENOMEM; + err = kobject_init_and_add(&watermarks->kobj, + &damon_sysfs_watermarks_ktype, &scheme->kobj, + "watermarks"); + if (err) + kobject_put(&watermarks->kobj); + else + scheme->watermarks = watermarks; + return err; +} + +static int damon_sysfs_scheme_set_stats(struct damon_sysfs_scheme *scheme) +{ + struct damon_sysfs_stats *stats = damon_sysfs_stats_alloc(); + int err; + + if (!stats) + return -ENOMEM; + err = kobject_init_and_add(&stats->kobj, &damon_sysfs_stats_ktype, + &scheme->kobj, "stats"); + if (err) + kobject_put(&stats->kobj); + else + scheme->stats = stats; + return err; +} + +static int damon_sysfs_scheme_add_dirs(struct damon_sysfs_scheme *scheme) +{ + int err; + + err = damon_sysfs_scheme_set_access_pattern(scheme); + if (err) + return err; + err = damon_sysfs_scheme_set_quotas(scheme); + if (err) + goto put_access_pattern_out; + err = damon_sysfs_scheme_set_watermarks(scheme); + if (err) + goto put_quotas_access_pattern_out; + err = damon_sysfs_scheme_set_stats(scheme); + if (err) + goto put_watermarks_quotas_access_pattern_out; + return 0; + +put_watermarks_quotas_access_pattern_out: + kobject_put(&scheme->watermarks->kobj); + scheme->watermarks = NULL; +put_quotas_access_pattern_out: + kobject_put(&scheme->quotas->kobj); + scheme->quotas = NULL; +put_access_pattern_out: + kobject_put(&scheme->access_pattern->kobj); + scheme->access_pattern = NULL; + return err; +} + +static void damon_sysfs_scheme_rm_dirs(struct damon_sysfs_scheme *scheme) +{ + damon_sysfs_access_pattern_rm_dirs(scheme->access_pattern); + kobject_put(&scheme->access_pattern->kobj); + damon_sysfs_quotas_rm_dirs(scheme->quotas); + kobject_put(&scheme->quotas->kobj); + kobject_put(&scheme->watermarks->kobj); + kobject_put(&scheme->stats->kobj); +} + +static ssize_t action_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_scheme *scheme = container_of(kobj, + struct damon_sysfs_scheme, kobj); + + return sysfs_emit(buf, "%s\n", + damon_sysfs_damos_action_strs[scheme->action]); +} + +static ssize_t action_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct damon_sysfs_scheme *scheme = container_of(kobj, + struct damon_sysfs_scheme, kobj); + enum damos_action action; + + for (action = 0; action < NR_DAMOS_ACTIONS; action++) { + if (sysfs_streq(buf, damon_sysfs_damos_action_strs[action])) { + scheme->action = action; + return count; + } + } + return -EINVAL; +} + +static void damon_sysfs_scheme_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_scheme, kobj)); +} + +static struct kobj_attribute damon_sysfs_scheme_action_attr = + __ATTR_RW_MODE(action, 0600); + +static struct attribute *damon_sysfs_scheme_attrs[] = { + &damon_sysfs_scheme_action_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_scheme); + +static struct kobj_type damon_sysfs_scheme_ktype = { + .release = damon_sysfs_scheme_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_scheme_groups, +}; + +/* + * schemes directory + */ + +struct damon_sysfs_schemes { + struct kobject kobj; + struct damon_sysfs_scheme **schemes_arr; + int nr; +}; + +static struct damon_sysfs_schemes *damon_sysfs_schemes_alloc(void) +{ + return kzalloc(sizeof(struct damon_sysfs_schemes), GFP_KERNEL); +} + +static void damon_sysfs_schemes_rm_dirs(struct damon_sysfs_schemes *schemes) +{ + struct damon_sysfs_scheme **schemes_arr = schemes->schemes_arr; + int i; + + for (i = 0; i < schemes->nr; i++) { + damon_sysfs_scheme_rm_dirs(schemes_arr[i]); + kobject_put(&schemes_arr[i]->kobj); + } + schemes->nr = 0; + kfree(schemes_arr); + schemes->schemes_arr = NULL; +} + +static int damon_sysfs_schemes_add_dirs(struct damon_sysfs_schemes *schemes, + int nr_schemes) +{ + struct damon_sysfs_scheme **schemes_arr, *scheme; + int err, i; + + damon_sysfs_schemes_rm_dirs(schemes); + if (!nr_schemes) + return 0; + + schemes_arr = kmalloc_array(nr_schemes, sizeof(*schemes_arr), + GFP_KERNEL | __GFP_NOWARN); + if (!schemes_arr) + return -ENOMEM; + schemes->schemes_arr = schemes_arr; + + for (i = 0; i < nr_schemes; i++) { + scheme = damon_sysfs_scheme_alloc(DAMOS_STAT); + if (!scheme) { + damon_sysfs_schemes_rm_dirs(schemes); + return -ENOMEM; + } + + err = kobject_init_and_add(&scheme->kobj, + &damon_sysfs_scheme_ktype, &schemes->kobj, + "%d", i); + if (err) + goto out; + err = damon_sysfs_scheme_add_dirs(scheme); + if (err) + goto out; + + schemes_arr[i] = scheme; + schemes->nr++; + } + return 0; + +out: + damon_sysfs_schemes_rm_dirs(schemes); + kobject_put(&scheme->kobj); + return err; +} + +static ssize_t nr_schemes_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_schemes *schemes = container_of(kobj, + struct damon_sysfs_schemes, kobj); + + return sysfs_emit(buf, "%d\n", schemes->nr); +} + +static ssize_t nr_schemes_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_schemes *schemes; + int nr, err = kstrtoint(buf, 0, &nr); + + if (err) + return err; + if (nr < 0) + return -EINVAL; + + schemes = container_of(kobj, struct damon_sysfs_schemes, kobj); + + if (!mutex_trylock(&damon_sysfs_lock)) + return -EBUSY; + err = damon_sysfs_schemes_add_dirs(schemes, nr); + mutex_unlock(&damon_sysfs_lock); + if (err) + return err; + return count; +} + +static void damon_sysfs_schemes_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_schemes, kobj)); +} + +static struct kobj_attribute damon_sysfs_schemes_nr_attr = + __ATTR_RW_MODE(nr_schemes, 0600); + +static struct attribute *damon_sysfs_schemes_attrs[] = { + &damon_sysfs_schemes_nr_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_schemes); + +static struct kobj_type damon_sysfs_schemes_ktype = { + .release = damon_sysfs_schemes_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_schemes_groups, +}; + +/* + * init region directory + */ + +struct damon_sysfs_region { + struct kobject kobj; + unsigned long start; + unsigned long end; +}; + +static struct damon_sysfs_region *damon_sysfs_region_alloc( + unsigned long start, + unsigned long end) +{ + struct damon_sysfs_region *region = kmalloc(sizeof(*region), + GFP_KERNEL); + + if (!region) + return NULL; + region->kobj = (struct kobject){}; + region->start = start; + region->end = end; + return region; +} + +static ssize_t start_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_region *region = container_of(kobj, + struct damon_sysfs_region, kobj); + + return sysfs_emit(buf, "%lu\n", region->start); +} + +static ssize_t start_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct damon_sysfs_region *region = container_of(kobj, + struct damon_sysfs_region, kobj); + int err = kstrtoul(buf, 0, ®ion->start); + + return err ? err : count; +} + +static ssize_t end_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_region *region = container_of(kobj, + struct damon_sysfs_region, kobj); + + return sysfs_emit(buf, "%lu\n", region->end); +} + +static ssize_t end_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct damon_sysfs_region *region = container_of(kobj, + struct damon_sysfs_region, kobj); + int err = kstrtoul(buf, 0, ®ion->end); + + return err ? err : count; +} + +static void damon_sysfs_region_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_region, kobj)); +} + +static struct kobj_attribute damon_sysfs_region_start_attr = + __ATTR_RW_MODE(start, 0600); + +static struct kobj_attribute damon_sysfs_region_end_attr = + __ATTR_RW_MODE(end, 0600); + +static struct attribute *damon_sysfs_region_attrs[] = { + &damon_sysfs_region_start_attr.attr, + &damon_sysfs_region_end_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_region); + +static struct kobj_type damon_sysfs_region_ktype = { + .release = damon_sysfs_region_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_region_groups, +}; + +/* + * init_regions directory + */ + +struct damon_sysfs_regions { + struct kobject kobj; + struct damon_sysfs_region **regions_arr; + int nr; +}; + +static struct damon_sysfs_regions *damon_sysfs_regions_alloc(void) +{ + return kzalloc(sizeof(struct damon_sysfs_regions), GFP_KERNEL); +} + +static void damon_sysfs_regions_rm_dirs(struct damon_sysfs_regions *regions) +{ + struct damon_sysfs_region **regions_arr = regions->regions_arr; + int i; + + for (i = 0; i < regions->nr; i++) + kobject_put(®ions_arr[i]->kobj); + regions->nr = 0; + kfree(regions_arr); + regions->regions_arr = NULL; +} + +static int damon_sysfs_regions_add_dirs(struct damon_sysfs_regions *regions, + int nr_regions) +{ + struct damon_sysfs_region **regions_arr, *region; + int err, i; + + damon_sysfs_regions_rm_dirs(regions); + if (!nr_regions) + return 0; + + regions_arr = kmalloc_array(nr_regions, sizeof(*regions_arr), + GFP_KERNEL | __GFP_NOWARN); + if (!regions_arr) + return -ENOMEM; + regions->regions_arr = regions_arr; + + for (i = 0; i < nr_regions; i++) { + region = damon_sysfs_region_alloc(0, 0); + if (!region) { + damon_sysfs_regions_rm_dirs(regions); + return -ENOMEM; + } + + err = kobject_init_and_add(®ion->kobj, + &damon_sysfs_region_ktype, ®ions->kobj, + "%d", i); + if (err) { + kobject_put(®ion->kobj); + damon_sysfs_regions_rm_dirs(regions); + return err; + } + + regions_arr[i] = region; + regions->nr++; + } + return 0; +} + +static ssize_t nr_regions_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_regions *regions = container_of(kobj, + struct damon_sysfs_regions, kobj); + + return sysfs_emit(buf, "%d\n", regions->nr); +} + +static ssize_t nr_regions_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_regions *regions; + int nr, err = kstrtoint(buf, 0, &nr); + + if (err) + return err; + if (nr < 0) + return -EINVAL; + + regions = container_of(kobj, struct damon_sysfs_regions, kobj); + + if (!mutex_trylock(&damon_sysfs_lock)) + return -EBUSY; + err = damon_sysfs_regions_add_dirs(regions, nr); + mutex_unlock(&damon_sysfs_lock); + if (err) + return err; + + return count; +} + +static void damon_sysfs_regions_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_regions, kobj)); +} + +static struct kobj_attribute damon_sysfs_regions_nr_attr = + __ATTR_RW_MODE(nr_regions, 0600); + +static struct attribute *damon_sysfs_regions_attrs[] = { + &damon_sysfs_regions_nr_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_regions); + +static struct kobj_type damon_sysfs_regions_ktype = { + .release = damon_sysfs_regions_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_regions_groups, +}; + +/* + * target directory + */ + +struct damon_sysfs_target { + struct kobject kobj; + struct damon_sysfs_regions *regions; + int pid; +}; + +static struct damon_sysfs_target *damon_sysfs_target_alloc(void) +{ + return kzalloc(sizeof(struct damon_sysfs_target), GFP_KERNEL); +} + +static int damon_sysfs_target_add_dirs(struct damon_sysfs_target *target) +{ + struct damon_sysfs_regions *regions = damon_sysfs_regions_alloc(); + int err; + + if (!regions) + return -ENOMEM; + + err = kobject_init_and_add(®ions->kobj, &damon_sysfs_regions_ktype, + &target->kobj, "regions"); + if (err) + kobject_put(®ions->kobj); + else + target->regions = regions; + return err; +} + +static void damon_sysfs_target_rm_dirs(struct damon_sysfs_target *target) +{ + damon_sysfs_regions_rm_dirs(target->regions); + kobject_put(&target->regions->kobj); +} + +static ssize_t pid_target_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_target *target = container_of(kobj, + struct damon_sysfs_target, kobj); + + return sysfs_emit(buf, "%d\n", target->pid); +} + +static ssize_t pid_target_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_target *target = container_of(kobj, + struct damon_sysfs_target, kobj); + int err = kstrtoint(buf, 0, &target->pid); + + if (err) + return -EINVAL; + return count; +} + +static void damon_sysfs_target_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_target, kobj)); +} + +static struct kobj_attribute damon_sysfs_target_pid_attr = + __ATTR_RW_MODE(pid_target, 0600); + +static struct attribute *damon_sysfs_target_attrs[] = { + &damon_sysfs_target_pid_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_target); + +static struct kobj_type damon_sysfs_target_ktype = { + .release = damon_sysfs_target_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_target_groups, +}; + +/* + * targets directory + */ + +struct damon_sysfs_targets { + struct kobject kobj; + struct damon_sysfs_target **targets_arr; + int nr; +}; + +static struct damon_sysfs_targets *damon_sysfs_targets_alloc(void) +{ + return kzalloc(sizeof(struct damon_sysfs_targets), GFP_KERNEL); +} + +static void damon_sysfs_targets_rm_dirs(struct damon_sysfs_targets *targets) +{ + struct damon_sysfs_target **targets_arr = targets->targets_arr; + int i; + + for (i = 0; i < targets->nr; i++) { + damon_sysfs_target_rm_dirs(targets_arr[i]); + kobject_put(&targets_arr[i]->kobj); + } + targets->nr = 0; + kfree(targets_arr); + targets->targets_arr = NULL; +} + +static int damon_sysfs_targets_add_dirs(struct damon_sysfs_targets *targets, + int nr_targets) +{ + struct damon_sysfs_target **targets_arr, *target; + int err, i; + + damon_sysfs_targets_rm_dirs(targets); + if (!nr_targets) + return 0; + + targets_arr = kmalloc_array(nr_targets, sizeof(*targets_arr), + GFP_KERNEL | __GFP_NOWARN); + if (!targets_arr) + return -ENOMEM; + targets->targets_arr = targets_arr; + + for (i = 0; i < nr_targets; i++) { + target = damon_sysfs_target_alloc(); + if (!target) { + damon_sysfs_targets_rm_dirs(targets); + return -ENOMEM; + } + + err = kobject_init_and_add(&target->kobj, + &damon_sysfs_target_ktype, &targets->kobj, + "%d", i); + if (err) + goto out; + + err = damon_sysfs_target_add_dirs(target); + if (err) + goto out; + + targets_arr[i] = target; + targets->nr++; + } + return 0; + +out: + damon_sysfs_targets_rm_dirs(targets); + kobject_put(&target->kobj); + return err; +} + +static ssize_t nr_targets_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_targets *targets = container_of(kobj, + struct damon_sysfs_targets, kobj); + + return sysfs_emit(buf, "%d\n", targets->nr); +} + +static ssize_t nr_targets_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_targets *targets; + int nr, err = kstrtoint(buf, 0, &nr); + + if (err) + return err; + if (nr < 0) + return -EINVAL; + + targets = container_of(kobj, struct damon_sysfs_targets, kobj); + + if (!mutex_trylock(&damon_sysfs_lock)) + return -EBUSY; + err = damon_sysfs_targets_add_dirs(targets, nr); + mutex_unlock(&damon_sysfs_lock); + if (err) + return err; + + return count; +} + +static void damon_sysfs_targets_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_targets, kobj)); +} + +static struct kobj_attribute damon_sysfs_targets_nr_attr = + __ATTR_RW_MODE(nr_targets, 0600); + +static struct attribute *damon_sysfs_targets_attrs[] = { + &damon_sysfs_targets_nr_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_targets); + +static struct kobj_type damon_sysfs_targets_ktype = { + .release = damon_sysfs_targets_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_targets_groups, +}; + +/* + * intervals directory + */ + +struct damon_sysfs_intervals { + struct kobject kobj; + unsigned long sample_us; + unsigned long aggr_us; + unsigned long update_us; +}; + +static struct damon_sysfs_intervals *damon_sysfs_intervals_alloc( + unsigned long sample_us, unsigned long aggr_us, + unsigned long update_us) +{ + struct damon_sysfs_intervals *intervals = kmalloc(sizeof(*intervals), + GFP_KERNEL); + + if (!intervals) + return NULL; + + intervals->kobj = (struct kobject){}; + intervals->sample_us = sample_us; + intervals->aggr_us = aggr_us; + intervals->update_us = update_us; + return intervals; +} + +static ssize_t sample_us_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_intervals *intervals = container_of(kobj, + struct damon_sysfs_intervals, kobj); + + return sysfs_emit(buf, "%lu\n", intervals->sample_us); +} + +static ssize_t sample_us_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_intervals *intervals = container_of(kobj, + struct damon_sysfs_intervals, kobj); + unsigned long us; + int err = kstrtoul(buf, 0, &us); + + if (err) + return err; + + intervals->sample_us = us; + return count; +} + +static ssize_t aggr_us_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_intervals *intervals = container_of(kobj, + struct damon_sysfs_intervals, kobj); + + return sysfs_emit(buf, "%lu\n", intervals->aggr_us); +} + +static ssize_t aggr_us_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct damon_sysfs_intervals *intervals = container_of(kobj, + struct damon_sysfs_intervals, kobj); + unsigned long us; + int err = kstrtoul(buf, 0, &us); + + if (err) + return err; + + intervals->aggr_us = us; + return count; +} + +static ssize_t update_us_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_intervals *intervals = container_of(kobj, + struct damon_sysfs_intervals, kobj); + + return sysfs_emit(buf, "%lu\n", intervals->update_us); +} + +static ssize_t update_us_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_intervals *intervals = container_of(kobj, + struct damon_sysfs_intervals, kobj); + unsigned long us; + int err = kstrtoul(buf, 0, &us); + + if (err) + return err; + + intervals->update_us = us; + return count; +} + +static void damon_sysfs_intervals_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_intervals, kobj)); +} + +static struct kobj_attribute damon_sysfs_intervals_sample_us_attr = + __ATTR_RW_MODE(sample_us, 0600); + +static struct kobj_attribute damon_sysfs_intervals_aggr_us_attr = + __ATTR_RW_MODE(aggr_us, 0600); + +static struct kobj_attribute damon_sysfs_intervals_update_us_attr = + __ATTR_RW_MODE(update_us, 0600); + +static struct attribute *damon_sysfs_intervals_attrs[] = { + &damon_sysfs_intervals_sample_us_attr.attr, + &damon_sysfs_intervals_aggr_us_attr.attr, + &damon_sysfs_intervals_update_us_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_intervals); + +static struct kobj_type damon_sysfs_intervals_ktype = { + .release = damon_sysfs_intervals_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_intervals_groups, +}; + +/* + * monitoring_attrs directory + */ + +struct damon_sysfs_attrs { + struct kobject kobj; + struct damon_sysfs_intervals *intervals; + struct damon_sysfs_ul_range *nr_regions_range; +}; + +static struct damon_sysfs_attrs *damon_sysfs_attrs_alloc(void) +{ + struct damon_sysfs_attrs *attrs = kmalloc(sizeof(*attrs), GFP_KERNEL); + + if (!attrs) + return NULL; + attrs->kobj = (struct kobject){}; + return attrs; +} + +static int damon_sysfs_attrs_add_dirs(struct damon_sysfs_attrs *attrs) +{ + struct damon_sysfs_intervals *intervals; + struct damon_sysfs_ul_range *nr_regions_range; + int err; + + intervals = damon_sysfs_intervals_alloc(5000, 100000, 60000000); + if (!intervals) + return -ENOMEM; + + err = kobject_init_and_add(&intervals->kobj, + &damon_sysfs_intervals_ktype, &attrs->kobj, + "intervals"); + if (err) + goto put_intervals_out; + attrs->intervals = intervals; + + nr_regions_range = damon_sysfs_ul_range_alloc(10, 1000); + if (!nr_regions_range) { + err = -ENOMEM; + goto put_intervals_out; + } + + err = kobject_init_and_add(&nr_regions_range->kobj, + &damon_sysfs_ul_range_ktype, &attrs->kobj, + "nr_regions"); + if (err) + goto put_nr_regions_intervals_out; + attrs->nr_regions_range = nr_regions_range; + return 0; + +put_nr_regions_intervals_out: + kobject_put(&nr_regions_range->kobj); + attrs->nr_regions_range = NULL; +put_intervals_out: + kobject_put(&intervals->kobj); + attrs->intervals = NULL; + return err; +} + +static void damon_sysfs_attrs_rm_dirs(struct damon_sysfs_attrs *attrs) +{ + kobject_put(&attrs->nr_regions_range->kobj); + kobject_put(&attrs->intervals->kobj); +} + +static void damon_sysfs_attrs_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_attrs, kobj)); +} + +static struct attribute *damon_sysfs_attrs_attrs[] = { + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_attrs); + +static struct kobj_type damon_sysfs_attrs_ktype = { + .release = damon_sysfs_attrs_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_attrs_groups, +}; + +/* + * context directory + */ + +/* This should match with enum damon_ops_id */ +static const char * const damon_sysfs_ops_strs[] = { + "vaddr", + "fvaddr", + "paddr", +}; + +struct damon_sysfs_context { + struct kobject kobj; + enum damon_ops_id ops_id; + struct damon_sysfs_attrs *attrs; + struct damon_sysfs_targets *targets; + struct damon_sysfs_schemes *schemes; +}; + +static struct damon_sysfs_context *damon_sysfs_context_alloc( + enum damon_ops_id ops_id) +{ + struct damon_sysfs_context *context = kmalloc(sizeof(*context), + GFP_KERNEL); + + if (!context) + return NULL; + context->kobj = (struct kobject){}; + context->ops_id = ops_id; + return context; +} + +static int damon_sysfs_context_set_attrs(struct damon_sysfs_context *context) +{ + struct damon_sysfs_attrs *attrs = damon_sysfs_attrs_alloc(); + int err; + + if (!attrs) + return -ENOMEM; + err = kobject_init_and_add(&attrs->kobj, &damon_sysfs_attrs_ktype, + &context->kobj, "monitoring_attrs"); + if (err) + goto out; + err = damon_sysfs_attrs_add_dirs(attrs); + if (err) + goto out; + context->attrs = attrs; + return 0; + +out: + kobject_put(&attrs->kobj); + return err; +} + +static int damon_sysfs_context_set_targets(struct damon_sysfs_context *context) +{ + struct damon_sysfs_targets *targets = damon_sysfs_targets_alloc(); + int err; + + if (!targets) + return -ENOMEM; + err = kobject_init_and_add(&targets->kobj, &damon_sysfs_targets_ktype, + &context->kobj, "targets"); + if (err) { + kobject_put(&targets->kobj); + return err; + } + context->targets = targets; + return 0; +} + +static int damon_sysfs_context_set_schemes(struct damon_sysfs_context *context) +{ + struct damon_sysfs_schemes *schemes = damon_sysfs_schemes_alloc(); + int err; + + if (!schemes) + return -ENOMEM; + err = kobject_init_and_add(&schemes->kobj, &damon_sysfs_schemes_ktype, + &context->kobj, "schemes"); + if (err) { + kobject_put(&schemes->kobj); + return err; + } + context->schemes = schemes; + return 0; +} + +static int damon_sysfs_context_add_dirs(struct damon_sysfs_context *context) +{ + int err; + + err = damon_sysfs_context_set_attrs(context); + if (err) + return err; + + err = damon_sysfs_context_set_targets(context); + if (err) + goto put_attrs_out; + + err = damon_sysfs_context_set_schemes(context); + if (err) + goto put_targets_attrs_out; + return 0; + +put_targets_attrs_out: + kobject_put(&context->targets->kobj); + context->targets = NULL; +put_attrs_out: + kobject_put(&context->attrs->kobj); + context->attrs = NULL; + return err; +} + +static void damon_sysfs_context_rm_dirs(struct damon_sysfs_context *context) +{ + damon_sysfs_attrs_rm_dirs(context->attrs); + kobject_put(&context->attrs->kobj); + damon_sysfs_targets_rm_dirs(context->targets); + kobject_put(&context->targets->kobj); + damon_sysfs_schemes_rm_dirs(context->schemes); + kobject_put(&context->schemes->kobj); +} + +static ssize_t avail_operations_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + enum damon_ops_id id; + int len = 0; + + for (id = 0; id < NR_DAMON_OPS; id++) { + if (!damon_is_registered_ops(id)) + continue; + len += sysfs_emit_at(buf, len, "%s\n", + damon_sysfs_ops_strs[id]); + } + return len; +} + +static ssize_t operations_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_context *context = container_of(kobj, + struct damon_sysfs_context, kobj); + + return sysfs_emit(buf, "%s\n", damon_sysfs_ops_strs[context->ops_id]); +} + +static ssize_t operations_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_context *context = container_of(kobj, + struct damon_sysfs_context, kobj); + enum damon_ops_id id; + + for (id = 0; id < NR_DAMON_OPS; id++) { + if (sysfs_streq(buf, damon_sysfs_ops_strs[id])) { + context->ops_id = id; + return count; + } + } + return -EINVAL; +} + +static void damon_sysfs_context_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_context, kobj)); +} + +static struct kobj_attribute damon_sysfs_context_avail_operations_attr = + __ATTR_RO_MODE(avail_operations, 0400); + +static struct kobj_attribute damon_sysfs_context_operations_attr = + __ATTR_RW_MODE(operations, 0600); + +static struct attribute *damon_sysfs_context_attrs[] = { + &damon_sysfs_context_avail_operations_attr.attr, + &damon_sysfs_context_operations_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_context); + +static struct kobj_type damon_sysfs_context_ktype = { + .release = damon_sysfs_context_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_context_groups, +}; + +/* + * contexts directory + */ + +struct damon_sysfs_contexts { + struct kobject kobj; + struct damon_sysfs_context **contexts_arr; + int nr; +}; + +static struct damon_sysfs_contexts *damon_sysfs_contexts_alloc(void) +{ + return kzalloc(sizeof(struct damon_sysfs_contexts), GFP_KERNEL); +} + +static void damon_sysfs_contexts_rm_dirs(struct damon_sysfs_contexts *contexts) +{ + struct damon_sysfs_context **contexts_arr = contexts->contexts_arr; + int i; + + for (i = 0; i < contexts->nr; i++) { + damon_sysfs_context_rm_dirs(contexts_arr[i]); + kobject_put(&contexts_arr[i]->kobj); + } + contexts->nr = 0; + kfree(contexts_arr); + contexts->contexts_arr = NULL; +} + +static int damon_sysfs_contexts_add_dirs(struct damon_sysfs_contexts *contexts, + int nr_contexts) +{ + struct damon_sysfs_context **contexts_arr, *context; + int err, i; + + damon_sysfs_contexts_rm_dirs(contexts); + if (!nr_contexts) + return 0; + + contexts_arr = kmalloc_array(nr_contexts, sizeof(*contexts_arr), + GFP_KERNEL | __GFP_NOWARN); + if (!contexts_arr) + return -ENOMEM; + contexts->contexts_arr = contexts_arr; + + for (i = 0; i < nr_contexts; i++) { + context = damon_sysfs_context_alloc(DAMON_OPS_VADDR); + if (!context) { + damon_sysfs_contexts_rm_dirs(contexts); + return -ENOMEM; + } + + err = kobject_init_and_add(&context->kobj, + &damon_sysfs_context_ktype, &contexts->kobj, + "%d", i); + if (err) + goto out; + + err = damon_sysfs_context_add_dirs(context); + if (err) + goto out; + + contexts_arr[i] = context; + contexts->nr++; + } + return 0; + +out: + damon_sysfs_contexts_rm_dirs(contexts); + kobject_put(&context->kobj); + return err; +} + +static ssize_t nr_contexts_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_contexts *contexts = container_of(kobj, + struct damon_sysfs_contexts, kobj); + + return sysfs_emit(buf, "%d\n", contexts->nr); +} + +static ssize_t nr_contexts_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_contexts *contexts; + int nr, err; + + err = kstrtoint(buf, 0, &nr); + if (err) + return err; + /* TODO: support multiple contexts per kdamond */ + if (nr < 0 || 1 < nr) + return -EINVAL; + + contexts = container_of(kobj, struct damon_sysfs_contexts, kobj); + if (!mutex_trylock(&damon_sysfs_lock)) + return -EBUSY; + err = damon_sysfs_contexts_add_dirs(contexts, nr); + mutex_unlock(&damon_sysfs_lock); + if (err) + return err; + + return count; +} + +static void damon_sysfs_contexts_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_contexts, kobj)); +} + +static struct kobj_attribute damon_sysfs_contexts_nr_attr + = __ATTR_RW_MODE(nr_contexts, 0600); + +static struct attribute *damon_sysfs_contexts_attrs[] = { + &damon_sysfs_contexts_nr_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_contexts); + +static struct kobj_type damon_sysfs_contexts_ktype = { + .release = damon_sysfs_contexts_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_contexts_groups, +}; + +/* + * kdamond directory + */ + +struct damon_sysfs_kdamond { + struct kobject kobj; + struct damon_sysfs_contexts *contexts; + struct damon_ctx *damon_ctx; +}; + +static struct damon_sysfs_kdamond *damon_sysfs_kdamond_alloc(void) +{ + return kzalloc(sizeof(struct damon_sysfs_kdamond), GFP_KERNEL); +} + +static int damon_sysfs_kdamond_add_dirs(struct damon_sysfs_kdamond *kdamond) +{ + struct damon_sysfs_contexts *contexts; + int err; + + contexts = damon_sysfs_contexts_alloc(); + if (!contexts) + return -ENOMEM; + + err = kobject_init_and_add(&contexts->kobj, + &damon_sysfs_contexts_ktype, &kdamond->kobj, + "contexts"); + if (err) { + kobject_put(&contexts->kobj); + return err; + } + kdamond->contexts = contexts; + + return err; +} + +static void damon_sysfs_kdamond_rm_dirs(struct damon_sysfs_kdamond *kdamond) +{ + damon_sysfs_contexts_rm_dirs(kdamond->contexts); + kobject_put(&kdamond->contexts->kobj); +} + +static bool damon_sysfs_ctx_running(struct damon_ctx *ctx) +{ + bool running; + + mutex_lock(&ctx->kdamond_lock); + running = ctx->kdamond != NULL; + mutex_unlock(&ctx->kdamond_lock); + return running; +} + +/* + * enum damon_sysfs_cmd - Commands for a specific kdamond. + */ +enum damon_sysfs_cmd { + /* @DAMON_SYSFS_CMD_ON: Turn the kdamond on. */ + DAMON_SYSFS_CMD_ON, + /* @DAMON_SYSFS_CMD_OFF: Turn the kdamond off. */ + DAMON_SYSFS_CMD_OFF, + /* @DAMON_SYSFS_CMD_COMMIT: Update kdamond inputs. */ + DAMON_SYSFS_CMD_COMMIT, + /* + * @DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS: Update scheme stats sysfs + * files. + */ + DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS, + /* + * @NR_DAMON_SYSFS_CMDS: Total number of DAMON sysfs commands. + */ + NR_DAMON_SYSFS_CMDS, +}; + +/* Should match with enum damon_sysfs_cmd */ +static const char * const damon_sysfs_cmd_strs[] = { + "on", + "off", + "commit", + "update_schemes_stats", +}; + +/* + * struct damon_sysfs_cmd_request - A request to the DAMON callback. + * @cmd: The command that needs to be handled by the callback. + * @kdamond: The kobject wrapper that associated to the kdamond thread. + * + * This structure represents a sysfs command request that need to access some + * DAMON context-internal data. Because DAMON context-internal data can be + * safely accessed from DAMON callbacks without additional synchronization, the + * request will be handled by the DAMON callback. None-``NULL`` @kdamond means + * the request is valid. + */ +struct damon_sysfs_cmd_request { + enum damon_sysfs_cmd cmd; + struct damon_sysfs_kdamond *kdamond; +}; + +/* Current DAMON callback request. Protected by damon_sysfs_lock. */ +static struct damon_sysfs_cmd_request damon_sysfs_cmd_request; + +static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_kdamond *kdamond = container_of(kobj, + struct damon_sysfs_kdamond, kobj); + struct damon_ctx *ctx = kdamond->damon_ctx; + bool running; + + if (!ctx) + running = false; + else + running = damon_sysfs_ctx_running(ctx); + + return sysfs_emit(buf, "%s\n", running ? + damon_sysfs_cmd_strs[DAMON_SYSFS_CMD_ON] : + damon_sysfs_cmd_strs[DAMON_SYSFS_CMD_OFF]); +} + +static int damon_sysfs_set_attrs(struct damon_ctx *ctx, + struct damon_sysfs_attrs *sys_attrs) +{ + struct damon_sysfs_intervals *sys_intervals = sys_attrs->intervals; + struct damon_sysfs_ul_range *sys_nr_regions = + sys_attrs->nr_regions_range; + struct damon_attrs attrs = { + .sample_interval = sys_intervals->sample_us, + .aggr_interval = sys_intervals->aggr_us, + .ops_update_interval = sys_intervals->update_us, + .min_nr_regions = sys_nr_regions->min, + .max_nr_regions = sys_nr_regions->max, + }; + return damon_set_attrs(ctx, &attrs); +} + +static void damon_sysfs_destroy_targets(struct damon_ctx *ctx) +{ + struct damon_target *t, *next; + bool has_pid = damon_target_has_pid(ctx); + + damon_for_each_target_safe(t, next, ctx) { + if (has_pid) + put_pid(t->pid); + damon_destroy_target(t); + } +} + +static int damon_sysfs_set_regions(struct damon_target *t, + struct damon_sysfs_regions *sysfs_regions) +{ + struct damon_addr_range *ranges = kmalloc_array(sysfs_regions->nr, + sizeof(*ranges), GFP_KERNEL | __GFP_NOWARN); + int i, err = -EINVAL; + + if (!ranges) + return -ENOMEM; + for (i = 0; i < sysfs_regions->nr; i++) { + struct damon_sysfs_region *sys_region = + sysfs_regions->regions_arr[i]; + + if (sys_region->start > sys_region->end) + goto out; + + ranges[i].start = sys_region->start; + ranges[i].end = sys_region->end; + if (i == 0) + continue; + if (ranges[i - 1].end > ranges[i].start) + goto out; + } + err = damon_set_regions(t, ranges, sysfs_regions->nr); +out: + kfree(ranges); + return err; + +} + +static int damon_sysfs_add_target(struct damon_sysfs_target *sys_target, + struct damon_ctx *ctx) +{ + struct damon_target *t = damon_new_target(); + int err = -EINVAL; + + if (!t) + return -ENOMEM; + damon_add_target(ctx, t); + if (damon_target_has_pid(ctx)) { + t->pid = find_get_pid(sys_target->pid); + if (!t->pid) + goto destroy_targets_out; + } + err = damon_sysfs_set_regions(t, sys_target->regions); + if (err) + goto destroy_targets_out; + return 0; + +destroy_targets_out: + damon_sysfs_destroy_targets(ctx); + return err; +} + +static int damon_sysfs_update_target_pid(struct damon_target *target, int pid) +{ + struct pid *pid_new; + + pid_new = find_get_pid(pid); + if (!pid_new) + return -EINVAL; + + if (pid_new == target->pid) { + put_pid(pid_new); + return 0; + } + + put_pid(target->pid); + target->pid = pid_new; + return 0; +} + +static int damon_sysfs_update_target(struct damon_target *target, + struct damon_ctx *ctx, + struct damon_sysfs_target *sys_target) +{ + int err = 0; + + if (damon_target_has_pid(ctx)) { + err = damon_sysfs_update_target_pid(target, sys_target->pid); + if (err) + return err; + } + + /* + * Do monitoring target region boundary update only if one or more + * regions are set by the user. This is for keeping current monitoring + * target results and range easier, especially for dynamic monitoring + * target regions update ops like 'vaddr'. + */ + if (sys_target->regions->nr) + err = damon_sysfs_set_regions(target, sys_target->regions); + return err; +} + +static int damon_sysfs_set_targets(struct damon_ctx *ctx, + struct damon_sysfs_targets *sysfs_targets) +{ + struct damon_target *t, *next; + int i = 0, err; + + /* Multiple physical address space monitoring targets makes no sense */ + if (ctx->ops.id == DAMON_OPS_PADDR && sysfs_targets->nr > 1) + return -EINVAL; + + damon_for_each_target_safe(t, next, ctx) { + if (i < sysfs_targets->nr) { + err = damon_sysfs_update_target(t, ctx, + sysfs_targets->targets_arr[i]); + if (err) + return err; + } else { + if (damon_target_has_pid(ctx)) + put_pid(t->pid); + damon_destroy_target(t); + } + i++; + } + + for (; i < sysfs_targets->nr; i++) { + struct damon_sysfs_target *st = sysfs_targets->targets_arr[i]; + + err = damon_sysfs_add_target(st, ctx); + if (err) + return err; + } + return 0; +} + +static struct damos *damon_sysfs_mk_scheme( + struct damon_sysfs_scheme *sysfs_scheme) +{ + struct damon_sysfs_access_pattern *access_pattern = + sysfs_scheme->access_pattern; + struct damon_sysfs_quotas *sysfs_quotas = sysfs_scheme->quotas; + struct damon_sysfs_weights *sysfs_weights = sysfs_quotas->weights; + struct damon_sysfs_watermarks *sysfs_wmarks = sysfs_scheme->watermarks; + + struct damos_access_pattern pattern = { + .min_sz_region = access_pattern->sz->min, + .max_sz_region = access_pattern->sz->max, + .min_nr_accesses = access_pattern->nr_accesses->min, + .max_nr_accesses = access_pattern->nr_accesses->max, + .min_age_region = access_pattern->age->min, + .max_age_region = access_pattern->age->max, + }; + struct damos_quota quota = { + .ms = sysfs_quotas->ms, + .sz = sysfs_quotas->sz, + .reset_interval = sysfs_quotas->reset_interval_ms, + .weight_sz = sysfs_weights->sz, + .weight_nr_accesses = sysfs_weights->nr_accesses, + .weight_age = sysfs_weights->age, + }; + struct damos_watermarks wmarks = { + .metric = sysfs_wmarks->metric, + .interval = sysfs_wmarks->interval_us, + .high = sysfs_wmarks->high, + .mid = sysfs_wmarks->mid, + .low = sysfs_wmarks->low, + }; + + return damon_new_scheme(&pattern, sysfs_scheme->action, "a, + &wmarks); +} + +static void damon_sysfs_update_scheme(struct damos *scheme, + struct damon_sysfs_scheme *sysfs_scheme) +{ + struct damon_sysfs_access_pattern *access_pattern = + sysfs_scheme->access_pattern; + struct damon_sysfs_quotas *sysfs_quotas = sysfs_scheme->quotas; + struct damon_sysfs_weights *sysfs_weights = sysfs_quotas->weights; + struct damon_sysfs_watermarks *sysfs_wmarks = sysfs_scheme->watermarks; + + scheme->pattern.min_sz_region = access_pattern->sz->min; + scheme->pattern.max_sz_region = access_pattern->sz->max; + scheme->pattern.min_nr_accesses = access_pattern->nr_accesses->min; + scheme->pattern.max_nr_accesses = access_pattern->nr_accesses->max; + scheme->pattern.min_age_region = access_pattern->age->min; + scheme->pattern.max_age_region = access_pattern->age->max; + + scheme->action = sysfs_scheme->action; + + scheme->quota.ms = sysfs_quotas->ms; + scheme->quota.sz = sysfs_quotas->sz; + scheme->quota.reset_interval = sysfs_quotas->reset_interval_ms; + scheme->quota.weight_sz = sysfs_weights->sz; + scheme->quota.weight_nr_accesses = sysfs_weights->nr_accesses; + scheme->quota.weight_age = sysfs_weights->age; + + scheme->wmarks.metric = sysfs_wmarks->metric; + scheme->wmarks.interval = sysfs_wmarks->interval_us; + scheme->wmarks.high = sysfs_wmarks->high; + scheme->wmarks.mid = sysfs_wmarks->mid; + scheme->wmarks.low = sysfs_wmarks->low; +} + +static int damon_sysfs_set_schemes(struct damon_ctx *ctx, + struct damon_sysfs_schemes *sysfs_schemes) +{ + struct damos *scheme, *next; + int i = 0; + + damon_for_each_scheme_safe(scheme, next, ctx) { + if (i < sysfs_schemes->nr) + damon_sysfs_update_scheme(scheme, + sysfs_schemes->schemes_arr[i]); + else + damon_destroy_scheme(scheme); + i++; + } + + for (; i < sysfs_schemes->nr; i++) { + struct damos *scheme, *next; + + scheme = damon_sysfs_mk_scheme(sysfs_schemes->schemes_arr[i]); + if (!scheme) { + damon_for_each_scheme_safe(scheme, next, ctx) + damon_destroy_scheme(scheme); + return -ENOMEM; + } + damon_add_scheme(ctx, scheme); + } + return 0; +} + +static void damon_sysfs_before_terminate(struct damon_ctx *ctx) +{ + struct damon_target *t, *next; + + if (!damon_target_has_pid(ctx)) + return; + + mutex_lock(&ctx->kdamond_lock); + damon_for_each_target_safe(t, next, ctx) { + put_pid(t->pid); + damon_destroy_target(t); + } + mutex_unlock(&ctx->kdamond_lock); +} + +/* + * damon_sysfs_upd_schemes_stats() - Update schemes stats sysfs files. + * @kdamond: The kobject wrapper that associated to the kdamond thread. + * + * This function reads the schemes stats of specific kdamond and update the + * related values for sysfs files. This function should be called from DAMON + * callbacks while holding ``damon_syfs_lock``, to safely access the DAMON + * contexts-internal data and DAMON sysfs variables. + */ +static int damon_sysfs_upd_schemes_stats(struct damon_sysfs_kdamond *kdamond) +{ + struct damon_ctx *ctx = kdamond->damon_ctx; + struct damon_sysfs_schemes *sysfs_schemes; + struct damos *scheme; + int schemes_idx = 0; + + if (!ctx) + return -EINVAL; + sysfs_schemes = kdamond->contexts->contexts_arr[0]->schemes; + damon_for_each_scheme(scheme, ctx) { + struct damon_sysfs_stats *sysfs_stats; + + /* user could have removed the scheme sysfs dir */ + if (schemes_idx >= sysfs_schemes->nr) + break; + + sysfs_stats = sysfs_schemes->schemes_arr[schemes_idx++]->stats; + sysfs_stats->nr_tried = scheme->stat.nr_tried; + sysfs_stats->sz_tried = scheme->stat.sz_tried; + sysfs_stats->nr_applied = scheme->stat.nr_applied; + sysfs_stats->sz_applied = scheme->stat.sz_applied; + sysfs_stats->qt_exceeds = scheme->stat.qt_exceeds; + } + return 0; +} + +static inline bool damon_sysfs_kdamond_running( + struct damon_sysfs_kdamond *kdamond) +{ + return kdamond->damon_ctx && + damon_sysfs_ctx_running(kdamond->damon_ctx); +} + +static int damon_sysfs_apply_inputs(struct damon_ctx *ctx, + struct damon_sysfs_context *sys_ctx) +{ + int err; + + err = damon_select_ops(ctx, sys_ctx->ops_id); + if (err) + return err; + err = damon_sysfs_set_attrs(ctx, sys_ctx->attrs); + if (err) + return err; + err = damon_sysfs_set_targets(ctx, sys_ctx->targets); + if (err) + return err; + return damon_sysfs_set_schemes(ctx, sys_ctx->schemes); +} + +/* + * damon_sysfs_commit_input() - Commit user inputs to a running kdamond. + * @kdamond: The kobject wrapper for the associated kdamond. + * + * If the sysfs input is wrong, the kdamond will be terminated. + */ +static int damon_sysfs_commit_input(struct damon_sysfs_kdamond *kdamond) +{ + if (!damon_sysfs_kdamond_running(kdamond)) + return -EINVAL; + /* TODO: Support multiple contexts per kdamond */ + if (kdamond->contexts->nr != 1) + return -EINVAL; + + return damon_sysfs_apply_inputs(kdamond->damon_ctx, + kdamond->contexts->contexts_arr[0]); +} + +/* + * damon_sysfs_cmd_request_callback() - DAMON callback for handling requests. + * @c: The DAMON context of the callback. + * + * This function is periodically called back from the kdamond thread for @c. + * Then, it checks if there is a waiting DAMON sysfs request and handles it. + */ +static int damon_sysfs_cmd_request_callback(struct damon_ctx *c) +{ + struct damon_sysfs_kdamond *kdamond; + int err = 0; + + /* avoid deadlock due to concurrent state_store('off') */ + if (!mutex_trylock(&damon_sysfs_lock)) + return 0; + kdamond = damon_sysfs_cmd_request.kdamond; + if (!kdamond || kdamond->damon_ctx != c) + goto out; + switch (damon_sysfs_cmd_request.cmd) { + case DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS: + err = damon_sysfs_upd_schemes_stats(kdamond); + break; + case DAMON_SYSFS_CMD_COMMIT: + err = damon_sysfs_commit_input(kdamond); + break; + default: + break; + } + /* Mark the request as invalid now. */ + damon_sysfs_cmd_request.kdamond = NULL; +out: + mutex_unlock(&damon_sysfs_lock); + return err; +} + +static struct damon_ctx *damon_sysfs_build_ctx( + struct damon_sysfs_context *sys_ctx) +{ + struct damon_ctx *ctx = damon_new_ctx(); + int err; + + if (!ctx) + return ERR_PTR(-ENOMEM); + + err = damon_sysfs_apply_inputs(ctx, sys_ctx); + if (err) { + damon_destroy_ctx(ctx); + return ERR_PTR(err); + } + + ctx->callback.after_wmarks_check = damon_sysfs_cmd_request_callback; + ctx->callback.after_aggregation = damon_sysfs_cmd_request_callback; + ctx->callback.before_terminate = damon_sysfs_before_terminate; + return ctx; +} + +static int damon_sysfs_turn_damon_on(struct damon_sysfs_kdamond *kdamond) +{ + struct damon_ctx *ctx; + int err; + + if (damon_sysfs_kdamond_running(kdamond)) + return -EBUSY; + if (damon_sysfs_cmd_request.kdamond == kdamond) + return -EBUSY; + /* TODO: support multiple contexts per kdamond */ + if (kdamond->contexts->nr != 1) + return -EINVAL; + + if (kdamond->damon_ctx) + damon_destroy_ctx(kdamond->damon_ctx); + kdamond->damon_ctx = NULL; + + ctx = damon_sysfs_build_ctx(kdamond->contexts->contexts_arr[0]); + if (IS_ERR(ctx)) + return PTR_ERR(ctx); + err = damon_start(&ctx, 1, false); + if (err) { + damon_destroy_ctx(ctx); + return err; + } + kdamond->damon_ctx = ctx; + return err; +} + +static int damon_sysfs_turn_damon_off(struct damon_sysfs_kdamond *kdamond) +{ + if (!kdamond->damon_ctx) + return -EINVAL; + return damon_stop(&kdamond->damon_ctx, 1); + /* + * To allow users show final monitoring results of already turned-off + * DAMON, we free kdamond->damon_ctx in next + * damon_sysfs_turn_damon_on(), or kdamonds_nr_store() + */ +} + +/* + * damon_sysfs_handle_cmd() - Handle a command for a specific kdamond. + * @cmd: The command to handle. + * @kdamond: The kobject wrapper for the associated kdamond. + * + * This function handles a DAMON sysfs command for a kdamond. For commands + * that need to access running DAMON context-internal data, it requests + * handling of the command to the DAMON callback + * (@damon_sysfs_cmd_request_callback()) and wait until it is properly handled, + * or the context is completed. + * + * Return: 0 on success, negative error code otherwise. + */ +static int damon_sysfs_handle_cmd(enum damon_sysfs_cmd cmd, + struct damon_sysfs_kdamond *kdamond) +{ + bool need_wait = true; + + /* Handle commands that doesn't access DAMON context-internal data */ + switch (cmd) { + case DAMON_SYSFS_CMD_ON: + return damon_sysfs_turn_damon_on(kdamond); + case DAMON_SYSFS_CMD_OFF: + return damon_sysfs_turn_damon_off(kdamond); + default: + break; + } + + /* Pass the command to DAMON callback for safe DAMON context access */ + if (damon_sysfs_cmd_request.kdamond) + return -EBUSY; + if (!damon_sysfs_kdamond_running(kdamond)) + return -EINVAL; + damon_sysfs_cmd_request.cmd = cmd; + damon_sysfs_cmd_request.kdamond = kdamond; + + /* + * wait until damon_sysfs_cmd_request_callback() handles the request + * from kdamond context + */ + mutex_unlock(&damon_sysfs_lock); + while (need_wait) { + schedule_timeout_idle(msecs_to_jiffies(100)); + if (!mutex_trylock(&damon_sysfs_lock)) + continue; + if (!damon_sysfs_cmd_request.kdamond) { + /* damon_sysfs_cmd_request_callback() handled */ + need_wait = false; + } else if (!damon_sysfs_kdamond_running(kdamond)) { + /* kdamond has already finished */ + need_wait = false; + damon_sysfs_cmd_request.kdamond = NULL; + } + mutex_unlock(&damon_sysfs_lock); + } + mutex_lock(&damon_sysfs_lock); + return 0; +} + +static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct damon_sysfs_kdamond *kdamond = container_of(kobj, + struct damon_sysfs_kdamond, kobj); + enum damon_sysfs_cmd cmd; + ssize_t ret = -EINVAL; + + if (!mutex_trylock(&damon_sysfs_lock)) + return -EBUSY; + for (cmd = 0; cmd < NR_DAMON_SYSFS_CMDS; cmd++) { + if (sysfs_streq(buf, damon_sysfs_cmd_strs[cmd])) { + ret = damon_sysfs_handle_cmd(cmd, kdamond); + break; + } + } + mutex_unlock(&damon_sysfs_lock); + if (!ret) + ret = count; + return ret; +} + +static ssize_t pid_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_kdamond *kdamond = container_of(kobj, + struct damon_sysfs_kdamond, kobj); + struct damon_ctx *ctx; + int pid = -1; + + if (!mutex_trylock(&damon_sysfs_lock)) + return -EBUSY; + ctx = kdamond->damon_ctx; + if (!ctx) + goto out; + + mutex_lock(&ctx->kdamond_lock); + if (ctx->kdamond) + pid = ctx->kdamond->pid; + mutex_unlock(&ctx->kdamond_lock); +out: + mutex_unlock(&damon_sysfs_lock); + return sysfs_emit(buf, "%d\n", pid); +} + +static void damon_sysfs_kdamond_release(struct kobject *kobj) +{ + struct damon_sysfs_kdamond *kdamond = container_of(kobj, + struct damon_sysfs_kdamond, kobj); + + if (kdamond->damon_ctx) + damon_destroy_ctx(kdamond->damon_ctx); + kfree(kdamond); +} + +static struct kobj_attribute damon_sysfs_kdamond_state_attr = + __ATTR_RW_MODE(state, 0600); + +static struct kobj_attribute damon_sysfs_kdamond_pid_attr = + __ATTR_RO_MODE(pid, 0400); + +static struct attribute *damon_sysfs_kdamond_attrs[] = { + &damon_sysfs_kdamond_state_attr.attr, + &damon_sysfs_kdamond_pid_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_kdamond); + +static struct kobj_type damon_sysfs_kdamond_ktype = { + .release = damon_sysfs_kdamond_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_kdamond_groups, +}; + +/* + * kdamonds directory + */ + +struct damon_sysfs_kdamonds { + struct kobject kobj; + struct damon_sysfs_kdamond **kdamonds_arr; + int nr; +}; + +static struct damon_sysfs_kdamonds *damon_sysfs_kdamonds_alloc(void) +{ + return kzalloc(sizeof(struct damon_sysfs_kdamonds), GFP_KERNEL); +} + +static void damon_sysfs_kdamonds_rm_dirs(struct damon_sysfs_kdamonds *kdamonds) +{ + struct damon_sysfs_kdamond **kdamonds_arr = kdamonds->kdamonds_arr; + int i; + + for (i = 0; i < kdamonds->nr; i++) { + damon_sysfs_kdamond_rm_dirs(kdamonds_arr[i]); + kobject_put(&kdamonds_arr[i]->kobj); + } + kdamonds->nr = 0; + kfree(kdamonds_arr); + kdamonds->kdamonds_arr = NULL; +} + +static bool damon_sysfs_kdamonds_busy(struct damon_sysfs_kdamond **kdamonds, + int nr_kdamonds) +{ + int i; + + for (i = 0; i < nr_kdamonds; i++) { + if (damon_sysfs_kdamond_running(kdamonds[i]) || + damon_sysfs_cmd_request.kdamond == kdamonds[i]) + return true; + } + + return false; +} + +static int damon_sysfs_kdamonds_add_dirs(struct damon_sysfs_kdamonds *kdamonds, + int nr_kdamonds) +{ + struct damon_sysfs_kdamond **kdamonds_arr, *kdamond; + int err, i; + + if (damon_sysfs_kdamonds_busy(kdamonds->kdamonds_arr, kdamonds->nr)) + return -EBUSY; + + damon_sysfs_kdamonds_rm_dirs(kdamonds); + if (!nr_kdamonds) + return 0; + + kdamonds_arr = kmalloc_array(nr_kdamonds, sizeof(*kdamonds_arr), + GFP_KERNEL | __GFP_NOWARN); + if (!kdamonds_arr) + return -ENOMEM; + kdamonds->kdamonds_arr = kdamonds_arr; + + for (i = 0; i < nr_kdamonds; i++) { + kdamond = damon_sysfs_kdamond_alloc(); + if (!kdamond) { + damon_sysfs_kdamonds_rm_dirs(kdamonds); + return -ENOMEM; + } + + err = kobject_init_and_add(&kdamond->kobj, + &damon_sysfs_kdamond_ktype, &kdamonds->kobj, + "%d", i); + if (err) + goto out; + + err = damon_sysfs_kdamond_add_dirs(kdamond); + if (err) + goto out; + + kdamonds_arr[i] = kdamond; + kdamonds->nr++; + } + return 0; + +out: + damon_sysfs_kdamonds_rm_dirs(kdamonds); + kobject_put(&kdamond->kobj); + return err; +} + +static ssize_t nr_kdamonds_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_kdamonds *kdamonds = container_of(kobj, + struct damon_sysfs_kdamonds, kobj); + + return sysfs_emit(buf, "%d\n", kdamonds->nr); +} + +static ssize_t nr_kdamonds_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_kdamonds *kdamonds; + int nr, err; + + err = kstrtoint(buf, 0, &nr); + if (err) + return err; + if (nr < 0) + return -EINVAL; + + kdamonds = container_of(kobj, struct damon_sysfs_kdamonds, kobj); + + if (!mutex_trylock(&damon_sysfs_lock)) + return -EBUSY; + err = damon_sysfs_kdamonds_add_dirs(kdamonds, nr); + mutex_unlock(&damon_sysfs_lock); + if (err) + return err; + + return count; +} + +static void damon_sysfs_kdamonds_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_kdamonds, kobj)); +} + +static struct kobj_attribute damon_sysfs_kdamonds_nr_attr = + __ATTR_RW_MODE(nr_kdamonds, 0600); + +static struct attribute *damon_sysfs_kdamonds_attrs[] = { + &damon_sysfs_kdamonds_nr_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_kdamonds); + +static struct kobj_type damon_sysfs_kdamonds_ktype = { + .release = damon_sysfs_kdamonds_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_kdamonds_groups, +}; + +/* + * damon user interface directory + */ + +struct damon_sysfs_ui_dir { + struct kobject kobj; + struct damon_sysfs_kdamonds *kdamonds; +}; + +static struct damon_sysfs_ui_dir *damon_sysfs_ui_dir_alloc(void) +{ + return kzalloc(sizeof(struct damon_sysfs_ui_dir), GFP_KERNEL); +} + +static int damon_sysfs_ui_dir_add_dirs(struct damon_sysfs_ui_dir *ui_dir) +{ + struct damon_sysfs_kdamonds *kdamonds; + int err; + + kdamonds = damon_sysfs_kdamonds_alloc(); + if (!kdamonds) + return -ENOMEM; + + err = kobject_init_and_add(&kdamonds->kobj, + &damon_sysfs_kdamonds_ktype, &ui_dir->kobj, + "kdamonds"); + if (err) { + kobject_put(&kdamonds->kobj); + return err; + } + ui_dir->kdamonds = kdamonds; + return err; +} + +static void damon_sysfs_ui_dir_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_ui_dir, kobj)); +} + +static struct attribute *damon_sysfs_ui_dir_attrs[] = { + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_ui_dir); + +static struct kobj_type damon_sysfs_ui_dir_ktype = { + .release = damon_sysfs_ui_dir_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_ui_dir_groups, +}; + +static int __init damon_sysfs_init(void) +{ + struct kobject *damon_sysfs_root; + struct damon_sysfs_ui_dir *admin; + int err; + + damon_sysfs_root = kobject_create_and_add("damon", mm_kobj); + if (!damon_sysfs_root) + return -ENOMEM; + + admin = damon_sysfs_ui_dir_alloc(); + if (!admin) { + kobject_put(damon_sysfs_root); + return -ENOMEM; + } + err = kobject_init_and_add(&admin->kobj, &damon_sysfs_ui_dir_ktype, + damon_sysfs_root, "admin"); + if (err) + goto out; + err = damon_sysfs_ui_dir_add_dirs(admin); + if (err) + goto out; + return 0; + +out: + kobject_put(&admin->kobj); + kobject_put(damon_sysfs_root); + return err; +} +subsys_initcall(damon_sysfs_init); diff --git a/mm/damon/vaddr-test.h b/mm/damon/vaddr-test.h new file mode 100644 index 000000000..e939598af --- /dev/null +++ b/mm/damon/vaddr-test.h @@ -0,0 +1,316 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Data Access Monitor Unit Tests + * + * Copyright 2019 Amazon.com, Inc. or its affiliates. All rights reserved. + * + * Author: SeongJae Park <sjpark@amazon.de> + */ + +#ifdef CONFIG_DAMON_VADDR_KUNIT_TEST + +#ifndef _DAMON_VADDR_TEST_H +#define _DAMON_VADDR_TEST_H + +#include <kunit/test.h> + +static void __link_vmas(struct maple_tree *mt, struct vm_area_struct *vmas, + ssize_t nr_vmas) +{ + int i; + MA_STATE(mas, mt, 0, 0); + + if (!nr_vmas) + return; + + mas_lock(&mas); + for (i = 0; i < nr_vmas; i++) + vma_mas_store(&vmas[i], &mas); + mas_unlock(&mas); +} + +/* + * Test __damon_va_three_regions() function + * + * In case of virtual memory address spaces monitoring, DAMON converts the + * complex and dynamic memory mappings of each target task to three + * discontiguous regions which cover every mapped areas. However, the three + * regions should not include the two biggest unmapped areas in the original + * mapping, because the two biggest areas are normally the areas between 1) + * heap and the mmap()-ed regions, and 2) the mmap()-ed regions and stack. + * Because these two unmapped areas are very huge but obviously never accessed, + * covering the region is just a waste. + * + * '__damon_va_three_regions() receives an address space of a process. It + * first identifies the start of mappings, end of mappings, and the two biggest + * unmapped areas. After that, based on the information, it constructs the + * three regions and returns. For more detail, refer to the comment of + * 'damon_init_regions_of()' function definition in 'mm/damon.c' file. + * + * For example, suppose virtual address ranges of 10-20, 20-25, 200-210, + * 210-220, 300-305, and 307-330 (Other comments represent this mappings in + * more short form: 10-20-25, 200-210-220, 300-305, 307-330) of a process are + * mapped. To cover every mappings, the three regions should start with 10, + * and end with 305. The process also has three unmapped areas, 25-200, + * 220-300, and 305-307. Among those, 25-200 and 220-300 are the biggest two + * unmapped areas, and thus it should be converted to three regions of 10-25, + * 200-220, and 300-330. + */ +static void damon_test_three_regions_in_vmas(struct kunit *test) +{ + static struct mm_struct mm; + struct damon_addr_range regions[3] = {0,}; + /* 10-20-25, 200-210-220, 300-305, 307-330 */ + struct vm_area_struct vmas[] = { + (struct vm_area_struct) {.vm_start = 10, .vm_end = 20}, + (struct vm_area_struct) {.vm_start = 20, .vm_end = 25}, + (struct vm_area_struct) {.vm_start = 200, .vm_end = 210}, + (struct vm_area_struct) {.vm_start = 210, .vm_end = 220}, + (struct vm_area_struct) {.vm_start = 300, .vm_end = 305}, + (struct vm_area_struct) {.vm_start = 307, .vm_end = 330}, + }; + + mt_init_flags(&mm.mm_mt, MM_MT_FLAGS); + __link_vmas(&mm.mm_mt, vmas, ARRAY_SIZE(vmas)); + + __damon_va_three_regions(&mm, regions); + + KUNIT_EXPECT_EQ(test, 10ul, regions[0].start); + KUNIT_EXPECT_EQ(test, 25ul, regions[0].end); + KUNIT_EXPECT_EQ(test, 200ul, regions[1].start); + KUNIT_EXPECT_EQ(test, 220ul, regions[1].end); + KUNIT_EXPECT_EQ(test, 300ul, regions[2].start); + KUNIT_EXPECT_EQ(test, 330ul, regions[2].end); +} + +static struct damon_region *__nth_region_of(struct damon_target *t, int idx) +{ + struct damon_region *r; + unsigned int i = 0; + + damon_for_each_region(r, t) { + if (i++ == idx) + return r; + } + + return NULL; +} + +/* + * Test 'damon_set_regions()' + * + * test kunit object + * regions an array containing start/end addresses of current + * monitoring target regions + * nr_regions the number of the addresses in 'regions' + * three_regions The three regions that need to be applied now + * expected start/end addresses of monitoring target regions that + * 'three_regions' are applied + * nr_expected the number of addresses in 'expected' + * + * The memory mapping of the target processes changes dynamically. To follow + * the change, DAMON periodically reads the mappings, simplifies it to the + * three regions, and updates the monitoring target regions to fit in the three + * regions. The update of current target regions is the role of + * 'damon_set_regions()'. + * + * This test passes the given target regions and the new three regions that + * need to be applied to the function and check whether it updates the regions + * as expected. + */ +static void damon_do_test_apply_three_regions(struct kunit *test, + unsigned long *regions, int nr_regions, + struct damon_addr_range *three_regions, + unsigned long *expected, int nr_expected) +{ + struct damon_target *t; + struct damon_region *r; + int i; + + t = damon_new_target(); + for (i = 0; i < nr_regions / 2; i++) { + r = damon_new_region(regions[i * 2], regions[i * 2 + 1]); + damon_add_region(r, t); + } + + damon_set_regions(t, three_regions, 3); + + for (i = 0; i < nr_expected / 2; i++) { + r = __nth_region_of(t, i); + KUNIT_EXPECT_EQ(test, r->ar.start, expected[i * 2]); + KUNIT_EXPECT_EQ(test, r->ar.end, expected[i * 2 + 1]); + } + + damon_destroy_target(t); +} + +/* + * This function test most common case where the three big regions are only + * slightly changed. Target regions should adjust their boundary (10-20-30, + * 50-55, 70-80, 90-100) to fit with the new big regions or remove target + * regions (57-79) that now out of the three regions. + */ +static void damon_test_apply_three_regions1(struct kunit *test) +{ + /* 10-20-30, 50-55-57-59, 70-80-90-100 */ + unsigned long regions[] = {10, 20, 20, 30, 50, 55, 55, 57, 57, 59, + 70, 80, 80, 90, 90, 100}; + /* 5-27, 45-55, 73-104 */ + struct damon_addr_range new_three_regions[3] = { + (struct damon_addr_range){.start = 5, .end = 27}, + (struct damon_addr_range){.start = 45, .end = 55}, + (struct damon_addr_range){.start = 73, .end = 104} }; + /* 5-20-27, 45-55, 73-80-90-104 */ + unsigned long expected[] = {5, 20, 20, 27, 45, 55, + 73, 80, 80, 90, 90, 104}; + + damon_do_test_apply_three_regions(test, regions, ARRAY_SIZE(regions), + new_three_regions, expected, ARRAY_SIZE(expected)); +} + +/* + * Test slightly bigger change. Similar to above, but the second big region + * now require two target regions (50-55, 57-59) to be removed. + */ +static void damon_test_apply_three_regions2(struct kunit *test) +{ + /* 10-20-30, 50-55-57-59, 70-80-90-100 */ + unsigned long regions[] = {10, 20, 20, 30, 50, 55, 55, 57, 57, 59, + 70, 80, 80, 90, 90, 100}; + /* 5-27, 56-57, 65-104 */ + struct damon_addr_range new_three_regions[3] = { + (struct damon_addr_range){.start = 5, .end = 27}, + (struct damon_addr_range){.start = 56, .end = 57}, + (struct damon_addr_range){.start = 65, .end = 104} }; + /* 5-20-27, 56-57, 65-80-90-104 */ + unsigned long expected[] = {5, 20, 20, 27, 56, 57, + 65, 80, 80, 90, 90, 104}; + + damon_do_test_apply_three_regions(test, regions, ARRAY_SIZE(regions), + new_three_regions, expected, ARRAY_SIZE(expected)); +} + +/* + * Test a big change. The second big region has totally freed and mapped to + * different area (50-59 -> 61-63). The target regions which were in the old + * second big region (50-55-57-59) should be removed and new target region + * covering the second big region (61-63) should be created. + */ +static void damon_test_apply_three_regions3(struct kunit *test) +{ + /* 10-20-30, 50-55-57-59, 70-80-90-100 */ + unsigned long regions[] = {10, 20, 20, 30, 50, 55, 55, 57, 57, 59, + 70, 80, 80, 90, 90, 100}; + /* 5-27, 61-63, 65-104 */ + struct damon_addr_range new_three_regions[3] = { + (struct damon_addr_range){.start = 5, .end = 27}, + (struct damon_addr_range){.start = 61, .end = 63}, + (struct damon_addr_range){.start = 65, .end = 104} }; + /* 5-20-27, 61-63, 65-80-90-104 */ + unsigned long expected[] = {5, 20, 20, 27, 61, 63, + 65, 80, 80, 90, 90, 104}; + + damon_do_test_apply_three_regions(test, regions, ARRAY_SIZE(regions), + new_three_regions, expected, ARRAY_SIZE(expected)); +} + +/* + * Test another big change. Both of the second and third big regions (50-59 + * and 70-100) has totally freed and mapped to different area (30-32 and + * 65-68). The target regions which were in the old second and third big + * regions should now be removed and new target regions covering the new second + * and third big regions should be created. + */ +static void damon_test_apply_three_regions4(struct kunit *test) +{ + /* 10-20-30, 50-55-57-59, 70-80-90-100 */ + unsigned long regions[] = {10, 20, 20, 30, 50, 55, 55, 57, 57, 59, + 70, 80, 80, 90, 90, 100}; + /* 5-7, 30-32, 65-68 */ + struct damon_addr_range new_three_regions[3] = { + (struct damon_addr_range){.start = 5, .end = 7}, + (struct damon_addr_range){.start = 30, .end = 32}, + (struct damon_addr_range){.start = 65, .end = 68} }; + /* expect 5-7, 30-32, 65-68 */ + unsigned long expected[] = {5, 7, 30, 32, 65, 68}; + + damon_do_test_apply_three_regions(test, regions, ARRAY_SIZE(regions), + new_three_regions, expected, ARRAY_SIZE(expected)); +} + +static void damon_test_split_evenly_fail(struct kunit *test, + unsigned long start, unsigned long end, unsigned int nr_pieces) +{ + struct damon_target *t = damon_new_target(); + struct damon_region *r = damon_new_region(start, end); + + damon_add_region(r, t); + KUNIT_EXPECT_EQ(test, + damon_va_evenly_split_region(t, r, nr_pieces), -EINVAL); + KUNIT_EXPECT_EQ(test, damon_nr_regions(t), 1u); + + damon_for_each_region(r, t) { + KUNIT_EXPECT_EQ(test, r->ar.start, start); + KUNIT_EXPECT_EQ(test, r->ar.end, end); + } + + damon_free_target(t); +} + +static void damon_test_split_evenly_succ(struct kunit *test, + unsigned long start, unsigned long end, unsigned int nr_pieces) +{ + struct damon_target *t = damon_new_target(); + struct damon_region *r = damon_new_region(start, end); + unsigned long expected_width = (end - start) / nr_pieces; + unsigned long i = 0; + + damon_add_region(r, t); + KUNIT_EXPECT_EQ(test, + damon_va_evenly_split_region(t, r, nr_pieces), 0); + KUNIT_EXPECT_EQ(test, damon_nr_regions(t), nr_pieces); + + damon_for_each_region(r, t) { + if (i == nr_pieces - 1) { + KUNIT_EXPECT_EQ(test, + r->ar.start, start + i * expected_width); + KUNIT_EXPECT_EQ(test, r->ar.end, end); + break; + } + KUNIT_EXPECT_EQ(test, + r->ar.start, start + i++ * expected_width); + KUNIT_EXPECT_EQ(test, r->ar.end, start + i * expected_width); + } + damon_free_target(t); +} + +static void damon_test_split_evenly(struct kunit *test) +{ + KUNIT_EXPECT_EQ(test, damon_va_evenly_split_region(NULL, NULL, 5), + -EINVAL); + + damon_test_split_evenly_fail(test, 0, 100, 0); + damon_test_split_evenly_succ(test, 0, 100, 10); + damon_test_split_evenly_succ(test, 5, 59, 5); + damon_test_split_evenly_fail(test, 5, 6, 2); +} + +static struct kunit_case damon_test_cases[] = { + KUNIT_CASE(damon_test_three_regions_in_vmas), + KUNIT_CASE(damon_test_apply_three_regions1), + KUNIT_CASE(damon_test_apply_three_regions2), + KUNIT_CASE(damon_test_apply_three_regions3), + KUNIT_CASE(damon_test_apply_three_regions4), + KUNIT_CASE(damon_test_split_evenly), + {}, +}; + +static struct kunit_suite damon_test_suite = { + .name = "damon-operations", + .test_cases = damon_test_cases, +}; +kunit_test_suite(damon_test_suite); + +#endif /* _DAMON_VADDR_TEST_H */ + +#endif /* CONFIG_DAMON_VADDR_KUNIT_TEST */ diff --git a/mm/damon/vaddr.c b/mm/damon/vaddr.c new file mode 100644 index 000000000..26d561af7 --- /dev/null +++ b/mm/damon/vaddr.c @@ -0,0 +1,715 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DAMON Primitives for Virtual Address Spaces + * + * Author: SeongJae Park <sjpark@amazon.de> + */ + +#define pr_fmt(fmt) "damon-va: " fmt + +#include <asm-generic/mman-common.h> +#include <linux/highmem.h> +#include <linux/hugetlb.h> +#include <linux/mmu_notifier.h> +#include <linux/page_idle.h> +#include <linux/pagewalk.h> +#include <linux/sched/mm.h> + +#include "ops-common.h" + +#ifdef CONFIG_DAMON_VADDR_KUNIT_TEST +#undef DAMON_MIN_REGION +#define DAMON_MIN_REGION 1 +#endif + +/* + * 't->pid' should be the pointer to the relevant 'struct pid' having reference + * count. Caller must put the returned task, unless it is NULL. + */ +static inline struct task_struct *damon_get_task_struct(struct damon_target *t) +{ + return get_pid_task(t->pid, PIDTYPE_PID); +} + +/* + * Get the mm_struct of the given target + * + * Caller _must_ put the mm_struct after use, unless it is NULL. + * + * Returns the mm_struct of the target on success, NULL on failure + */ +static struct mm_struct *damon_get_mm(struct damon_target *t) +{ + struct task_struct *task; + struct mm_struct *mm; + + task = damon_get_task_struct(t); + if (!task) + return NULL; + + mm = get_task_mm(task); + put_task_struct(task); + return mm; +} + +/* + * Functions for the initial monitoring target regions construction + */ + +/* + * Size-evenly split a region into 'nr_pieces' small regions + * + * Returns 0 on success, or negative error code otherwise. + */ +static int damon_va_evenly_split_region(struct damon_target *t, + struct damon_region *r, unsigned int nr_pieces) +{ + unsigned long sz_orig, sz_piece, orig_end; + struct damon_region *n = NULL, *next; + unsigned long start; + + if (!r || !nr_pieces) + return -EINVAL; + + orig_end = r->ar.end; + sz_orig = damon_sz_region(r); + sz_piece = ALIGN_DOWN(sz_orig / nr_pieces, DAMON_MIN_REGION); + + if (!sz_piece) + return -EINVAL; + + r->ar.end = r->ar.start + sz_piece; + next = damon_next_region(r); + for (start = r->ar.end; start + sz_piece <= orig_end; + start += sz_piece) { + n = damon_new_region(start, start + sz_piece); + if (!n) + return -ENOMEM; + damon_insert_region(n, r, next, t); + r = n; + } + /* complement last region for possible rounding error */ + if (n) + n->ar.end = orig_end; + + return 0; +} + +static unsigned long sz_range(struct damon_addr_range *r) +{ + return r->end - r->start; +} + +/* + * Find three regions separated by two biggest unmapped regions + * + * vma the head vma of the target address space + * regions an array of three address ranges that results will be saved + * + * This function receives an address space and finds three regions in it which + * separated by the two biggest unmapped regions in the space. Please refer to + * below comments of '__damon_va_init_regions()' function to know why this is + * necessary. + * + * Returns 0 if success, or negative error code otherwise. + */ +static int __damon_va_three_regions(struct mm_struct *mm, + struct damon_addr_range regions[3]) +{ + struct damon_addr_range first_gap = {0}, second_gap = {0}; + VMA_ITERATOR(vmi, mm, 0); + struct vm_area_struct *vma, *prev = NULL; + unsigned long start; + + /* + * Find the two biggest gaps so that first_gap > second_gap > others. + * If this is too slow, it can be optimised to examine the maple + * tree gaps. + */ + for_each_vma(vmi, vma) { + unsigned long gap; + + if (!prev) { + start = vma->vm_start; + goto next; + } + gap = vma->vm_start - prev->vm_end; + + if (gap > sz_range(&first_gap)) { + second_gap = first_gap; + first_gap.start = prev->vm_end; + first_gap.end = vma->vm_start; + } else if (gap > sz_range(&second_gap)) { + second_gap.start = prev->vm_end; + second_gap.end = vma->vm_start; + } +next: + prev = vma; + } + + if (!sz_range(&second_gap) || !sz_range(&first_gap)) + return -EINVAL; + + /* Sort the two biggest gaps by address */ + if (first_gap.start > second_gap.start) + swap(first_gap, second_gap); + + /* Store the result */ + regions[0].start = ALIGN(start, DAMON_MIN_REGION); + regions[0].end = ALIGN(first_gap.start, DAMON_MIN_REGION); + regions[1].start = ALIGN(first_gap.end, DAMON_MIN_REGION); + regions[1].end = ALIGN(second_gap.start, DAMON_MIN_REGION); + regions[2].start = ALIGN(second_gap.end, DAMON_MIN_REGION); + regions[2].end = ALIGN(prev->vm_end, DAMON_MIN_REGION); + + return 0; +} + +/* + * Get the three regions in the given target (task) + * + * Returns 0 on success, negative error code otherwise. + */ +static int damon_va_three_regions(struct damon_target *t, + struct damon_addr_range regions[3]) +{ + struct mm_struct *mm; + int rc; + + mm = damon_get_mm(t); + if (!mm) + return -EINVAL; + + mmap_read_lock(mm); + rc = __damon_va_three_regions(mm, regions); + mmap_read_unlock(mm); + + mmput(mm); + return rc; +} + +/* + * Initialize the monitoring target regions for the given target (task) + * + * t the given target + * + * Because only a number of small portions of the entire address space + * is actually mapped to the memory and accessed, monitoring the unmapped + * regions is wasteful. That said, because we can deal with small noises, + * tracking every mapping is not strictly required but could even incur a high + * overhead if the mapping frequently changes or the number of mappings is + * high. The adaptive regions adjustment mechanism will further help to deal + * with the noise by simply identifying the unmapped areas as a region that + * has no access. Moreover, applying the real mappings that would have many + * unmapped areas inside will make the adaptive mechanism quite complex. That + * said, too huge unmapped areas inside the monitoring target should be removed + * to not take the time for the adaptive mechanism. + * + * For the reason, we convert the complex mappings to three distinct regions + * that cover every mapped area of the address space. Also the two gaps + * between the three regions are the two biggest unmapped areas in the given + * address space. In detail, this function first identifies the start and the + * end of the mappings and the two biggest unmapped areas of the address space. + * Then, it constructs the three regions as below: + * + * [mappings[0]->start, big_two_unmapped_areas[0]->start) + * [big_two_unmapped_areas[0]->end, big_two_unmapped_areas[1]->start) + * [big_two_unmapped_areas[1]->end, mappings[nr_mappings - 1]->end) + * + * As usual memory map of processes is as below, the gap between the heap and + * the uppermost mmap()-ed region, and the gap between the lowermost mmap()-ed + * region and the stack will be two biggest unmapped regions. Because these + * gaps are exceptionally huge areas in usual address space, excluding these + * two biggest unmapped regions will be sufficient to make a trade-off. + * + * <heap> + * <BIG UNMAPPED REGION 1> + * <uppermost mmap()-ed region> + * (other mmap()-ed regions and small unmapped regions) + * <lowermost mmap()-ed region> + * <BIG UNMAPPED REGION 2> + * <stack> + */ +static void __damon_va_init_regions(struct damon_ctx *ctx, + struct damon_target *t) +{ + struct damon_target *ti; + struct damon_region *r; + struct damon_addr_range regions[3]; + unsigned long sz = 0, nr_pieces; + int i, tidx = 0; + + if (damon_va_three_regions(t, regions)) { + damon_for_each_target(ti, ctx) { + if (ti == t) + break; + tidx++; + } + pr_debug("Failed to get three regions of %dth target\n", tidx); + return; + } + + for (i = 0; i < 3; i++) + sz += regions[i].end - regions[i].start; + if (ctx->attrs.min_nr_regions) + sz /= ctx->attrs.min_nr_regions; + if (sz < DAMON_MIN_REGION) + sz = DAMON_MIN_REGION; + + /* Set the initial three regions of the target */ + for (i = 0; i < 3; i++) { + r = damon_new_region(regions[i].start, regions[i].end); + if (!r) { + pr_err("%d'th init region creation failed\n", i); + return; + } + damon_add_region(r, t); + + nr_pieces = (regions[i].end - regions[i].start) / sz; + damon_va_evenly_split_region(t, r, nr_pieces); + } +} + +/* Initialize '->regions_list' of every target (task) */ +static void damon_va_init(struct damon_ctx *ctx) +{ + struct damon_target *t; + + damon_for_each_target(t, ctx) { + /* the user may set the target regions as they want */ + if (!damon_nr_regions(t)) + __damon_va_init_regions(ctx, t); + } +} + +/* + * Update regions for current memory mappings + */ +static void damon_va_update(struct damon_ctx *ctx) +{ + struct damon_addr_range three_regions[3]; + struct damon_target *t; + + damon_for_each_target(t, ctx) { + if (damon_va_three_regions(t, three_regions)) + continue; + damon_set_regions(t, three_regions, 3); + } +} + +static int damon_mkold_pmd_entry(pmd_t *pmd, unsigned long addr, + unsigned long next, struct mm_walk *walk) +{ + pte_t *pte; + spinlock_t *ptl; + + if (pmd_trans_huge(*pmd)) { + ptl = pmd_lock(walk->mm, pmd); + if (!pmd_present(*pmd)) { + spin_unlock(ptl); + return 0; + } + + if (pmd_trans_huge(*pmd)) { + damon_pmdp_mkold(pmd, walk->vma, addr); + spin_unlock(ptl); + return 0; + } + spin_unlock(ptl); + } + + if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd))) + return 0; + pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); + if (!pte_present(*pte)) + goto out; + damon_ptep_mkold(pte, walk->vma, addr); +out: + pte_unmap_unlock(pte, ptl); + return 0; +} + +#ifdef CONFIG_HUGETLB_PAGE +static void damon_hugetlb_mkold(pte_t *pte, struct mm_struct *mm, + struct vm_area_struct *vma, unsigned long addr) +{ + bool referenced = false; + pte_t entry = huge_ptep_get(pte); + struct page *page = pte_page(entry); + + get_page(page); + + if (pte_young(entry)) { + referenced = true; + entry = pte_mkold(entry); + set_huge_pte_at(mm, addr, pte, entry); + } + +#ifdef CONFIG_MMU_NOTIFIER + if (mmu_notifier_clear_young(mm, addr, + addr + huge_page_size(hstate_vma(vma)))) + referenced = true; +#endif /* CONFIG_MMU_NOTIFIER */ + + if (referenced) + set_page_young(page); + + set_page_idle(page); + put_page(page); +} + +static int damon_mkold_hugetlb_entry(pte_t *pte, unsigned long hmask, + unsigned long addr, unsigned long end, + struct mm_walk *walk) +{ + struct hstate *h = hstate_vma(walk->vma); + spinlock_t *ptl; + pte_t entry; + + ptl = huge_pte_lock(h, walk->mm, pte); + entry = huge_ptep_get(pte); + if (!pte_present(entry)) + goto out; + + damon_hugetlb_mkold(pte, walk->mm, walk->vma, addr); + +out: + spin_unlock(ptl); + return 0; +} +#else +#define damon_mkold_hugetlb_entry NULL +#endif /* CONFIG_HUGETLB_PAGE */ + +static const struct mm_walk_ops damon_mkold_ops = { + .pmd_entry = damon_mkold_pmd_entry, + .hugetlb_entry = damon_mkold_hugetlb_entry, +}; + +static void damon_va_mkold(struct mm_struct *mm, unsigned long addr) +{ + mmap_read_lock(mm); + walk_page_range(mm, addr, addr + 1, &damon_mkold_ops, NULL); + mmap_read_unlock(mm); +} + +/* + * Functions for the access checking of the regions + */ + +static void __damon_va_prepare_access_check(struct mm_struct *mm, + struct damon_region *r) +{ + r->sampling_addr = damon_rand(r->ar.start, r->ar.end); + + damon_va_mkold(mm, r->sampling_addr); +} + +static void damon_va_prepare_access_checks(struct damon_ctx *ctx) +{ + struct damon_target *t; + struct mm_struct *mm; + struct damon_region *r; + + damon_for_each_target(t, ctx) { + mm = damon_get_mm(t); + if (!mm) + continue; + damon_for_each_region(r, t) + __damon_va_prepare_access_check(mm, r); + mmput(mm); + } +} + +struct damon_young_walk_private { + unsigned long *page_sz; + bool young; +}; + +static int damon_young_pmd_entry(pmd_t *pmd, unsigned long addr, + unsigned long next, struct mm_walk *walk) +{ + pte_t *pte; + spinlock_t *ptl; + struct page *page; + struct damon_young_walk_private *priv = walk->private; + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + if (pmd_trans_huge(*pmd)) { + ptl = pmd_lock(walk->mm, pmd); + if (!pmd_present(*pmd)) { + spin_unlock(ptl); + return 0; + } + + if (!pmd_trans_huge(*pmd)) { + spin_unlock(ptl); + goto regular_page; + } + page = damon_get_page(pmd_pfn(*pmd)); + if (!page) + goto huge_out; + if (pmd_young(*pmd) || !page_is_idle(page) || + mmu_notifier_test_young(walk->mm, + addr)) { + *priv->page_sz = HPAGE_PMD_SIZE; + priv->young = true; + } + put_page(page); +huge_out: + spin_unlock(ptl); + return 0; + } + +regular_page: +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ + + if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd))) + return -EINVAL; + pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); + if (!pte_present(*pte)) + goto out; + page = damon_get_page(pte_pfn(*pte)); + if (!page) + goto out; + if (pte_young(*pte) || !page_is_idle(page) || + mmu_notifier_test_young(walk->mm, addr)) { + *priv->page_sz = PAGE_SIZE; + priv->young = true; + } + put_page(page); +out: + pte_unmap_unlock(pte, ptl); + return 0; +} + +#ifdef CONFIG_HUGETLB_PAGE +static int damon_young_hugetlb_entry(pte_t *pte, unsigned long hmask, + unsigned long addr, unsigned long end, + struct mm_walk *walk) +{ + struct damon_young_walk_private *priv = walk->private; + struct hstate *h = hstate_vma(walk->vma); + struct page *page; + spinlock_t *ptl; + pte_t entry; + + ptl = huge_pte_lock(h, walk->mm, pte); + entry = huge_ptep_get(pte); + if (!pte_present(entry)) + goto out; + + page = pte_page(entry); + get_page(page); + + if (pte_young(entry) || !page_is_idle(page) || + mmu_notifier_test_young(walk->mm, addr)) { + *priv->page_sz = huge_page_size(h); + priv->young = true; + } + + put_page(page); + +out: + spin_unlock(ptl); + return 0; +} +#else +#define damon_young_hugetlb_entry NULL +#endif /* CONFIG_HUGETLB_PAGE */ + +static const struct mm_walk_ops damon_young_ops = { + .pmd_entry = damon_young_pmd_entry, + .hugetlb_entry = damon_young_hugetlb_entry, +}; + +static bool damon_va_young(struct mm_struct *mm, unsigned long addr, + unsigned long *page_sz) +{ + struct damon_young_walk_private arg = { + .page_sz = page_sz, + .young = false, + }; + + mmap_read_lock(mm); + walk_page_range(mm, addr, addr + 1, &damon_young_ops, &arg); + mmap_read_unlock(mm); + return arg.young; +} + +/* + * Check whether the region was accessed after the last preparation + * + * mm 'mm_struct' for the given virtual address space + * r the region to be checked + */ +static void __damon_va_check_access(struct mm_struct *mm, + struct damon_region *r, bool same_target) +{ + static unsigned long last_addr; + static unsigned long last_page_sz = PAGE_SIZE; + static bool last_accessed; + + /* If the region is in the last checked page, reuse the result */ + if (same_target && (ALIGN_DOWN(last_addr, last_page_sz) == + ALIGN_DOWN(r->sampling_addr, last_page_sz))) { + if (last_accessed) + r->nr_accesses++; + return; + } + + last_accessed = damon_va_young(mm, r->sampling_addr, &last_page_sz); + if (last_accessed) + r->nr_accesses++; + + last_addr = r->sampling_addr; +} + +static unsigned int damon_va_check_accesses(struct damon_ctx *ctx) +{ + struct damon_target *t; + struct mm_struct *mm; + struct damon_region *r; + unsigned int max_nr_accesses = 0; + bool same_target; + + damon_for_each_target(t, ctx) { + mm = damon_get_mm(t); + if (!mm) + continue; + same_target = false; + damon_for_each_region(r, t) { + __damon_va_check_access(mm, r, same_target); + max_nr_accesses = max(r->nr_accesses, max_nr_accesses); + same_target = true; + } + mmput(mm); + } + + return max_nr_accesses; +} + +/* + * Functions for the target validity check and cleanup + */ + +static bool damon_va_target_valid(struct damon_target *t) +{ + struct task_struct *task; + + task = damon_get_task_struct(t); + if (task) { + put_task_struct(task); + return true; + } + + return false; +} + +#ifndef CONFIG_ADVISE_SYSCALLS +static unsigned long damos_madvise(struct damon_target *target, + struct damon_region *r, int behavior) +{ + return 0; +} +#else +static unsigned long damos_madvise(struct damon_target *target, + struct damon_region *r, int behavior) +{ + struct mm_struct *mm; + unsigned long start = PAGE_ALIGN(r->ar.start); + unsigned long len = PAGE_ALIGN(damon_sz_region(r)); + unsigned long applied; + + mm = damon_get_mm(target); + if (!mm) + return 0; + + applied = do_madvise(mm, start, len, behavior) ? 0 : len; + mmput(mm); + + return applied; +} +#endif /* CONFIG_ADVISE_SYSCALLS */ + +static unsigned long damon_va_apply_scheme(struct damon_ctx *ctx, + struct damon_target *t, struct damon_region *r, + struct damos *scheme) +{ + int madv_action; + + switch (scheme->action) { + case DAMOS_WILLNEED: + madv_action = MADV_WILLNEED; + break; + case DAMOS_COLD: + madv_action = MADV_COLD; + break; + case DAMOS_PAGEOUT: + madv_action = MADV_PAGEOUT; + break; + case DAMOS_HUGEPAGE: + madv_action = MADV_HUGEPAGE; + break; + case DAMOS_NOHUGEPAGE: + madv_action = MADV_NOHUGEPAGE; + break; + case DAMOS_STAT: + return 0; + default: + /* + * DAMOS actions that are not yet supported by 'vaddr'. + */ + return 0; + } + + return damos_madvise(t, r, madv_action); +} + +static int damon_va_scheme_score(struct damon_ctx *context, + struct damon_target *t, struct damon_region *r, + struct damos *scheme) +{ + + switch (scheme->action) { + case DAMOS_PAGEOUT: + return damon_cold_score(context, r, scheme); + default: + break; + } + + return DAMOS_MAX_SCORE; +} + +static int __init damon_va_initcall(void) +{ + struct damon_operations ops = { + .id = DAMON_OPS_VADDR, + .init = damon_va_init, + .update = damon_va_update, + .prepare_access_checks = damon_va_prepare_access_checks, + .check_accesses = damon_va_check_accesses, + .reset_aggregated = NULL, + .target_valid = damon_va_target_valid, + .cleanup = NULL, + .apply_scheme = damon_va_apply_scheme, + .get_scheme_score = damon_va_scheme_score, + }; + /* ops for fixed virtual address ranges */ + struct damon_operations ops_fvaddr = ops; + int err; + + /* Don't set the monitoring target regions for the entire mapping */ + ops_fvaddr.id = DAMON_OPS_FVADDR; + ops_fvaddr.init = NULL; + ops_fvaddr.update = NULL; + + err = damon_register_ops(&ops); + if (err) + return err; + return damon_register_ops(&ops_fvaddr); +}; + +subsys_initcall(damon_va_initcall); + +#include "vaddr-test.h" |