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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /mm/damon/lru_sort.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.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/lru_sort.c')
-rw-r--r--mm/damon/lru_sort.c340
1 files changed, 340 insertions, 0 deletions
diff --git a/mm/damon/lru_sort.c b/mm/damon/lru_sort.c
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+// 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. */
+ &quota,
+ /* (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);