diff options
Diffstat (limited to 'arch/powerpc/perf/hv-24x7.c')
| -rw-r--r-- | arch/powerpc/perf/hv-24x7.c | 1623 |
1 files changed, 1623 insertions, 0 deletions
diff --git a/arch/powerpc/perf/hv-24x7.c b/arch/powerpc/perf/hv-24x7.c new file mode 100644 index 000000000..2bb798918 --- /dev/null +++ b/arch/powerpc/perf/hv-24x7.c @@ -0,0 +1,1623 @@ +/* + * Hypervisor supplied "24x7" performance counter support + * + * Author: Cody P Schafer <cody@linux.vnet.ibm.com> + * Copyright 2014 IBM Corporation. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#define pr_fmt(fmt) "hv-24x7: " fmt + +#include <linux/perf_event.h> +#include <linux/rbtree.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/vmalloc.h> + +#include <asm/cputhreads.h> +#include <asm/firmware.h> +#include <asm/hvcall.h> +#include <asm/io.h> +#include <linux/byteorder/generic.h> + +#include "hv-24x7.h" +#include "hv-24x7-catalog.h" +#include "hv-common.h" + +/* Version of the 24x7 hypervisor API that we should use in this machine. */ +static int interface_version; + +/* Whether we have to aggregate result data for some domains. */ +static bool aggregate_result_elements; + +static bool domain_is_valid(unsigned domain) +{ + switch (domain) { +#define DOMAIN(n, v, x, c) \ + case HV_PERF_DOMAIN_##n: \ + /* fall through */ +#include "hv-24x7-domains.h" +#undef DOMAIN + return true; + default: + return false; + } +} + +static bool is_physical_domain(unsigned domain) +{ + switch (domain) { +#define DOMAIN(n, v, x, c) \ + case HV_PERF_DOMAIN_##n: \ + return c; +#include "hv-24x7-domains.h" +#undef DOMAIN + default: + return false; + } +} + +/* Domains for which more than one result element are returned for each event. */ +static bool domain_needs_aggregation(unsigned int domain) +{ + return aggregate_result_elements && + (domain == HV_PERF_DOMAIN_PHYS_CORE || + (domain >= HV_PERF_DOMAIN_VCPU_HOME_CORE && + domain <= HV_PERF_DOMAIN_VCPU_REMOTE_NODE)); +} + +static const char *domain_name(unsigned domain) +{ + if (!domain_is_valid(domain)) + return NULL; + + switch (domain) { + case HV_PERF_DOMAIN_PHYS_CHIP: return "Physical Chip"; + case HV_PERF_DOMAIN_PHYS_CORE: return "Physical Core"; + case HV_PERF_DOMAIN_VCPU_HOME_CORE: return "VCPU Home Core"; + case HV_PERF_DOMAIN_VCPU_HOME_CHIP: return "VCPU Home Chip"; + case HV_PERF_DOMAIN_VCPU_HOME_NODE: return "VCPU Home Node"; + case HV_PERF_DOMAIN_VCPU_REMOTE_NODE: return "VCPU Remote Node"; + } + + WARN_ON_ONCE(domain); + return NULL; +} + +static bool catalog_entry_domain_is_valid(unsigned domain) +{ + /* POWER8 doesn't support virtual domains. */ + if (interface_version == 1) + return is_physical_domain(domain); + else + return domain_is_valid(domain); +} + +/* + * TODO: Merging events: + * - Think of the hcall as an interface to a 4d array of counters: + * - x = domains + * - y = indexes in the domain (core, chip, vcpu, node, etc) + * - z = offset into the counter space + * - w = lpars (guest vms, "logical partitions") + * - A single request is: x,y,y_last,z,z_last,w,w_last + * - this means we can retrieve a rectangle of counters in y,z for a single x. + * + * - Things to consider (ignoring w): + * - input cost_per_request = 16 + * - output cost_per_result(ys,zs) = 8 + 8 * ys + ys * zs + * - limited number of requests per hcall (must fit into 4K bytes) + * - 4k = 16 [buffer header] - 16 [request size] * request_count + * - 255 requests per hcall + * - sometimes it will be more efficient to read extra data and discard + */ + +/* + * Example usage: + * perf stat -e 'hv_24x7/domain=2,offset=8,vcpu=0,lpar=0xffffffff/' + */ + +/* u3 0-6, one of HV_24X7_PERF_DOMAIN */ +EVENT_DEFINE_RANGE_FORMAT(domain, config, 0, 3); +/* u16 */ +EVENT_DEFINE_RANGE_FORMAT(core, config, 16, 31); +EVENT_DEFINE_RANGE_FORMAT(chip, config, 16, 31); +EVENT_DEFINE_RANGE_FORMAT(vcpu, config, 16, 31); +/* u32, see "data_offset" */ +EVENT_DEFINE_RANGE_FORMAT(offset, config, 32, 63); +/* u16 */ +EVENT_DEFINE_RANGE_FORMAT(lpar, config1, 0, 15); + +EVENT_DEFINE_RANGE(reserved1, config, 4, 15); +EVENT_DEFINE_RANGE(reserved2, config1, 16, 63); +EVENT_DEFINE_RANGE(reserved3, config2, 0, 63); + +static struct attribute *format_attrs[] = { + &format_attr_domain.attr, + &format_attr_offset.attr, + &format_attr_core.attr, + &format_attr_chip.attr, + &format_attr_vcpu.attr, + &format_attr_lpar.attr, + NULL, +}; + +static struct attribute_group format_group = { + .name = "format", + .attrs = format_attrs, +}; + +static struct attribute_group event_group = { + .name = "events", + /* .attrs is set in init */ +}; + +static struct attribute_group event_desc_group = { + .name = "event_descs", + /* .attrs is set in init */ +}; + +static struct attribute_group event_long_desc_group = { + .name = "event_long_descs", + /* .attrs is set in init */ +}; + +static struct kmem_cache *hv_page_cache; + +DEFINE_PER_CPU(int, hv_24x7_txn_flags); +DEFINE_PER_CPU(int, hv_24x7_txn_err); + +struct hv_24x7_hw { + struct perf_event *events[255]; +}; + +DEFINE_PER_CPU(struct hv_24x7_hw, hv_24x7_hw); + +/* + * request_buffer and result_buffer are not required to be 4k aligned, + * but are not allowed to cross any 4k boundary. Aligning them to 4k is + * the simplest way to ensure that. + */ +#define H24x7_DATA_BUFFER_SIZE 4096 +DEFINE_PER_CPU(char, hv_24x7_reqb[H24x7_DATA_BUFFER_SIZE]) __aligned(4096); +DEFINE_PER_CPU(char, hv_24x7_resb[H24x7_DATA_BUFFER_SIZE]) __aligned(4096); + +static unsigned int max_num_requests(int interface_version) +{ + return (H24x7_DATA_BUFFER_SIZE - sizeof(struct hv_24x7_request_buffer)) + / H24x7_REQUEST_SIZE(interface_version); +} + +static char *event_name(struct hv_24x7_event_data *ev, int *len) +{ + *len = be16_to_cpu(ev->event_name_len) - 2; + return (char *)ev->remainder; +} + +static char *event_desc(struct hv_24x7_event_data *ev, int *len) +{ + unsigned nl = be16_to_cpu(ev->event_name_len); + __be16 *desc_len = (__be16 *)(ev->remainder + nl - 2); + + *len = be16_to_cpu(*desc_len) - 2; + return (char *)ev->remainder + nl; +} + +static char *event_long_desc(struct hv_24x7_event_data *ev, int *len) +{ + unsigned nl = be16_to_cpu(ev->event_name_len); + __be16 *desc_len_ = (__be16 *)(ev->remainder + nl - 2); + unsigned desc_len = be16_to_cpu(*desc_len_); + __be16 *long_desc_len = (__be16 *)(ev->remainder + nl + desc_len - 2); + + *len = be16_to_cpu(*long_desc_len) - 2; + return (char *)ev->remainder + nl + desc_len; +} + +static bool event_fixed_portion_is_within(struct hv_24x7_event_data *ev, + void *end) +{ + void *start = ev; + + return (start + offsetof(struct hv_24x7_event_data, remainder)) < end; +} + +/* + * Things we don't check: + * - padding for desc, name, and long/detailed desc is required to be '\0' + * bytes. + * + * Return NULL if we pass end, + * Otherwise return the address of the byte just following the event. + */ +static void *event_end(struct hv_24x7_event_data *ev, void *end) +{ + void *start = ev; + __be16 *dl_, *ldl_; + unsigned dl, ldl; + unsigned nl = be16_to_cpu(ev->event_name_len); + + if (nl < 2) { + pr_debug("%s: name length too short: %d", __func__, nl); + return NULL; + } + + if (start + nl > end) { + pr_debug("%s: start=%p + nl=%u > end=%p", + __func__, start, nl, end); + return NULL; + } + + dl_ = (__be16 *)(ev->remainder + nl - 2); + if (!IS_ALIGNED((uintptr_t)dl_, 2)) + pr_warn("desc len not aligned %p", dl_); + dl = be16_to_cpu(*dl_); + if (dl < 2) { + pr_debug("%s: desc len too short: %d", __func__, dl); + return NULL; + } + + if (start + nl + dl > end) { + pr_debug("%s: (start=%p + nl=%u + dl=%u)=%p > end=%p", + __func__, start, nl, dl, start + nl + dl, end); + return NULL; + } + + ldl_ = (__be16 *)(ev->remainder + nl + dl - 2); + if (!IS_ALIGNED((uintptr_t)ldl_, 2)) + pr_warn("long desc len not aligned %p", ldl_); + ldl = be16_to_cpu(*ldl_); + if (ldl < 2) { + pr_debug("%s: long desc len too short (ldl=%u)", + __func__, ldl); + return NULL; + } + + if (start + nl + dl + ldl > end) { + pr_debug("%s: start=%p + nl=%u + dl=%u + ldl=%u > end=%p", + __func__, start, nl, dl, ldl, end); + return NULL; + } + + return start + nl + dl + ldl; +} + +static long h_get_24x7_catalog_page_(unsigned long phys_4096, + unsigned long version, unsigned long index) +{ + pr_devel("h_get_24x7_catalog_page(0x%lx, %lu, %lu)", + phys_4096, version, index); + + WARN_ON(!IS_ALIGNED(phys_4096, 4096)); + + return plpar_hcall_norets(H_GET_24X7_CATALOG_PAGE, + phys_4096, version, index); +} + +static long h_get_24x7_catalog_page(char page[], u64 version, u32 index) +{ + return h_get_24x7_catalog_page_(virt_to_phys(page), + version, index); +} + +/* + * Each event we find in the catalog, will have a sysfs entry. Format the + * data for this sysfs entry based on the event's domain. + * + * Events belonging to the Chip domain can only be monitored in that domain. + * i.e the domain for these events is a fixed/knwon value. + * + * Events belonging to the Core domain can be monitored either in the physical + * core or in one of the virtual CPU domains. So the domain value for these + * events must be specified by the user (i.e is a required parameter). Format + * the Core events with 'domain=?' so the perf-tool can error check required + * parameters. + * + * NOTE: For the Core domain events, rather than making domain a required + * parameter we could default it to PHYS_CORE and allowe users to + * override the domain to one of the VCPU domains. + * + * However, this can make the interface a little inconsistent. + * + * If we set domain=2 (PHYS_CHIP) and allow user to override this field + * the user may be tempted to also modify the "offset=x" field in which + * can lead to confusing usage. Consider the HPM_PCYC (offset=0x18) and + * HPM_INST (offset=0x20) events. With: + * + * perf stat -e hv_24x7/HPM_PCYC,offset=0x20/ + * + * we end up monitoring HPM_INST, while the command line has HPM_PCYC. + * + * By not assigning a default value to the domain for the Core events, + * we can have simple guidelines: + * + * - Specifying values for parameters with "=?" is required. + * + * - Specifying (i.e overriding) values for other parameters + * is undefined. + */ +static char *event_fmt(struct hv_24x7_event_data *event, unsigned domain) +{ + const char *sindex; + const char *lpar; + const char *domain_str; + char buf[8]; + + switch (domain) { + case HV_PERF_DOMAIN_PHYS_CHIP: + snprintf(buf, sizeof(buf), "%d", domain); + domain_str = buf; + lpar = "0x0"; + sindex = "chip"; + break; + case HV_PERF_DOMAIN_PHYS_CORE: + domain_str = "?"; + lpar = "0x0"; + sindex = "core"; + break; + default: + domain_str = "?"; + lpar = "?"; + sindex = "vcpu"; + } + + return kasprintf(GFP_KERNEL, + "domain=%s,offset=0x%x,%s=?,lpar=%s", + domain_str, + be16_to_cpu(event->event_counter_offs) + + be16_to_cpu(event->event_group_record_offs), + sindex, + lpar); +} + +/* Avoid trusting fw to NUL terminate strings */ +static char *memdup_to_str(char *maybe_str, int max_len, gfp_t gfp) +{ + return kasprintf(gfp, "%.*s", max_len, maybe_str); +} + +static ssize_t device_show_string(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct dev_ext_attribute *d; + + d = container_of(attr, struct dev_ext_attribute, attr); + + return sprintf(buf, "%s\n", (char *)d->var); +} + +static struct attribute *device_str_attr_create_(char *name, char *str) +{ + struct dev_ext_attribute *attr = kzalloc(sizeof(*attr), GFP_KERNEL); + + if (!attr) + return NULL; + + sysfs_attr_init(&attr->attr.attr); + + attr->var = str; + attr->attr.attr.name = name; + attr->attr.attr.mode = 0444; + attr->attr.show = device_show_string; + + return &attr->attr.attr; +} + +/* + * Allocate and initialize strings representing event attributes. + * + * NOTE: The strings allocated here are never destroyed and continue to + * exist till shutdown. This is to allow us to create as many events + * from the catalog as possible, even if we encounter errors with some. + * In case of changes to error paths in future, these may need to be + * freed by the caller. + */ +static struct attribute *device_str_attr_create(char *name, int name_max, + int name_nonce, + char *str, size_t str_max) +{ + char *n; + char *s = memdup_to_str(str, str_max, GFP_KERNEL); + struct attribute *a; + + if (!s) + return NULL; + + if (!name_nonce) + n = kasprintf(GFP_KERNEL, "%.*s", name_max, name); + else + n = kasprintf(GFP_KERNEL, "%.*s__%d", name_max, name, + name_nonce); + if (!n) + goto out_s; + + a = device_str_attr_create_(n, s); + if (!a) + goto out_n; + + return a; +out_n: + kfree(n); +out_s: + kfree(s); + return NULL; +} + +static struct attribute *event_to_attr(unsigned ix, + struct hv_24x7_event_data *event, + unsigned domain, + int nonce) +{ + int event_name_len; + char *ev_name, *a_ev_name, *val; + struct attribute *attr; + + if (!domain_is_valid(domain)) { + pr_warn("catalog event %u has invalid domain %u\n", + ix, domain); + return NULL; + } + + val = event_fmt(event, domain); + if (!val) + return NULL; + + ev_name = event_name(event, &event_name_len); + if (!nonce) + a_ev_name = kasprintf(GFP_KERNEL, "%.*s", + (int)event_name_len, ev_name); + else + a_ev_name = kasprintf(GFP_KERNEL, "%.*s__%d", + (int)event_name_len, ev_name, nonce); + + if (!a_ev_name) + goto out_val; + + attr = device_str_attr_create_(a_ev_name, val); + if (!attr) + goto out_name; + + return attr; +out_name: + kfree(a_ev_name); +out_val: + kfree(val); + return NULL; +} + +static struct attribute *event_to_desc_attr(struct hv_24x7_event_data *event, + int nonce) +{ + int nl, dl; + char *name = event_name(event, &nl); + char *desc = event_desc(event, &dl); + + /* If there isn't a description, don't create the sysfs file */ + if (!dl) + return NULL; + + return device_str_attr_create(name, nl, nonce, desc, dl); +} + +static struct attribute * +event_to_long_desc_attr(struct hv_24x7_event_data *event, int nonce) +{ + int nl, dl; + char *name = event_name(event, &nl); + char *desc = event_long_desc(event, &dl); + + /* If there isn't a description, don't create the sysfs file */ + if (!dl) + return NULL; + + return device_str_attr_create(name, nl, nonce, desc, dl); +} + +static int event_data_to_attrs(unsigned ix, struct attribute **attrs, + struct hv_24x7_event_data *event, int nonce) +{ + *attrs = event_to_attr(ix, event, event->domain, nonce); + if (!*attrs) + return -1; + + return 0; +} + +/* */ +struct event_uniq { + struct rb_node node; + const char *name; + int nl; + unsigned ct; + unsigned domain; +}; + +static int memord(const void *d1, size_t s1, const void *d2, size_t s2) +{ + if (s1 < s2) + return 1; + if (s1 > s2) + return -1; + + return memcmp(d1, d2, s1); +} + +static int ev_uniq_ord(const void *v1, size_t s1, unsigned d1, const void *v2, + size_t s2, unsigned d2) +{ + int r = memord(v1, s1, v2, s2); + + if (r) + return r; + if (d1 > d2) + return 1; + if (d2 > d1) + return -1; + return 0; +} + +static int event_uniq_add(struct rb_root *root, const char *name, int nl, + unsigned domain) +{ + struct rb_node **new = &(root->rb_node), *parent = NULL; + struct event_uniq *data; + + /* Figure out where to put new node */ + while (*new) { + struct event_uniq *it; + int result; + + it = container_of(*new, struct event_uniq, node); + result = ev_uniq_ord(name, nl, domain, it->name, it->nl, + it->domain); + + parent = *new; + if (result < 0) + new = &((*new)->rb_left); + else if (result > 0) + new = &((*new)->rb_right); + else { + it->ct++; + pr_info("found a duplicate event %.*s, ct=%u\n", nl, + name, it->ct); + return it->ct; + } + } + + data = kmalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + *data = (struct event_uniq) { + .name = name, + .nl = nl, + .ct = 0, + .domain = domain, + }; + + /* Add new node and rebalance tree. */ + rb_link_node(&data->node, parent, new); + rb_insert_color(&data->node, root); + + /* data->ct */ + return 0; +} + +static void event_uniq_destroy(struct rb_root *root) +{ + /* + * the strings we point to are in the giant block of memory filled by + * the catalog, and are freed separately. + */ + struct event_uniq *pos, *n; + + rbtree_postorder_for_each_entry_safe(pos, n, root, node) + kfree(pos); +} + + +/* + * ensure the event structure's sizes are self consistent and don't cause us to + * read outside of the event + * + * On success, return the event length in bytes. + * Otherwise, return -1 (and print as appropriate). + */ +static ssize_t catalog_event_len_validate(struct hv_24x7_event_data *event, + size_t event_idx, + size_t event_data_bytes, + size_t event_entry_count, + size_t offset, void *end) +{ + ssize_t ev_len; + void *ev_end, *calc_ev_end; + + if (offset >= event_data_bytes) + return -1; + + if (event_idx >= event_entry_count) { + pr_devel("catalog event data has %zu bytes of padding after last event\n", + event_data_bytes - offset); + return -1; + } + + if (!event_fixed_portion_is_within(event, end)) { + pr_warn("event %zu fixed portion is not within range\n", + event_idx); + return -1; + } + + ev_len = be16_to_cpu(event->length); + + if (ev_len % 16) + pr_info("event %zu has length %zu not divisible by 16: event=%pK\n", + event_idx, ev_len, event); + + ev_end = (__u8 *)event + ev_len; + if (ev_end > end) { + pr_warn("event %zu has .length=%zu, ends after buffer end: ev_end=%pK > end=%pK, offset=%zu\n", + event_idx, ev_len, ev_end, end, + offset); + return -1; + } + + calc_ev_end = event_end(event, end); + if (!calc_ev_end) { + pr_warn("event %zu has a calculated length which exceeds buffer length %zu: event=%pK end=%pK, offset=%zu\n", + event_idx, event_data_bytes, event, end, + offset); + return -1; + } + + if (calc_ev_end > ev_end) { + pr_warn("event %zu exceeds it's own length: event=%pK, end=%pK, offset=%zu, calc_ev_end=%pK\n", + event_idx, event, ev_end, offset, calc_ev_end); + return -1; + } + + return ev_len; +} + +#define MAX_4K (SIZE_MAX / 4096) + +static int create_events_from_catalog(struct attribute ***events_, + struct attribute ***event_descs_, + struct attribute ***event_long_descs_) +{ + long hret; + size_t catalog_len, catalog_page_len, event_entry_count, + event_data_len, event_data_offs, + event_data_bytes, junk_events, event_idx, event_attr_ct, i, + attr_max, event_idx_last, desc_ct, long_desc_ct; + ssize_t ct, ev_len; + uint64_t catalog_version_num; + struct attribute **events, **event_descs, **event_long_descs; + struct hv_24x7_catalog_page_0 *page_0 = + kmem_cache_alloc(hv_page_cache, GFP_KERNEL); + void *page = page_0; + void *event_data, *end; + struct hv_24x7_event_data *event; + struct rb_root ev_uniq = RB_ROOT; + int ret = 0; + + if (!page) { + ret = -ENOMEM; + goto e_out; + } + + hret = h_get_24x7_catalog_page(page, 0, 0); + if (hret) { + ret = -EIO; + goto e_free; + } + + catalog_version_num = be64_to_cpu(page_0->version); + catalog_page_len = be32_to_cpu(page_0->length); + + if (MAX_4K < catalog_page_len) { + pr_err("invalid page count: %zu\n", catalog_page_len); + ret = -EIO; + goto e_free; + } + + catalog_len = catalog_page_len * 4096; + + event_entry_count = be16_to_cpu(page_0->event_entry_count); + event_data_offs = be16_to_cpu(page_0->event_data_offs); + event_data_len = be16_to_cpu(page_0->event_data_len); + + pr_devel("cv %llu cl %zu eec %zu edo %zu edl %zu\n", + catalog_version_num, catalog_len, + event_entry_count, event_data_offs, event_data_len); + + if ((MAX_4K < event_data_len) + || (MAX_4K < event_data_offs) + || (MAX_4K - event_data_offs < event_data_len)) { + pr_err("invalid event data offs %zu and/or len %zu\n", + event_data_offs, event_data_len); + ret = -EIO; + goto e_free; + } + + if ((event_data_offs + event_data_len) > catalog_page_len) { + pr_err("event data %zu-%zu does not fit inside catalog 0-%zu\n", + event_data_offs, + event_data_offs + event_data_len, + catalog_page_len); + ret = -EIO; + goto e_free; + } + + if (SIZE_MAX - 1 < event_entry_count) { + pr_err("event_entry_count %zu is invalid\n", event_entry_count); + ret = -EIO; + goto e_free; + } + + event_data_bytes = event_data_len * 4096; + + /* + * event data can span several pages, events can cross between these + * pages. Use vmalloc to make this easier. + */ + event_data = vmalloc(event_data_bytes); + if (!event_data) { + pr_err("could not allocate event data\n"); + ret = -ENOMEM; + goto e_free; + } + + end = event_data + event_data_bytes; + + /* + * using vmalloc_to_phys() like this only works if PAGE_SIZE is + * divisible by 4096 + */ + BUILD_BUG_ON(PAGE_SIZE % 4096); + + for (i = 0; i < event_data_len; i++) { + hret = h_get_24x7_catalog_page_( + vmalloc_to_phys(event_data + i * 4096), + catalog_version_num, + i + event_data_offs); + if (hret) { + pr_err("Failed to get event data in page %zu: rc=%ld\n", + i + event_data_offs, hret); + ret = -EIO; + goto e_event_data; + } + } + + /* + * scan the catalog to determine the number of attributes we need, and + * verify it at the same time. + */ + for (junk_events = 0, event = event_data, event_idx = 0, attr_max = 0; + ; + event_idx++, event = (void *)event + ev_len) { + size_t offset = (void *)event - (void *)event_data; + char *name; + int nl; + + ev_len = catalog_event_len_validate(event, event_idx, + event_data_bytes, + event_entry_count, + offset, end); + if (ev_len < 0) + break; + + name = event_name(event, &nl); + + if (event->event_group_record_len == 0) { + pr_devel("invalid event %zu (%.*s): group_record_len == 0, skipping\n", + event_idx, nl, name); + junk_events++; + continue; + } + + if (!catalog_entry_domain_is_valid(event->domain)) { + pr_info("event %zu (%.*s) has invalid domain %d\n", + event_idx, nl, name, event->domain); + junk_events++; + continue; + } + + attr_max++; + } + + event_idx_last = event_idx; + if (event_idx_last != event_entry_count) + pr_warn("event buffer ended before listed # of events were parsed (got %zu, wanted %zu, junk %zu)\n", + event_idx_last, event_entry_count, junk_events); + + events = kmalloc_array(attr_max + 1, sizeof(*events), GFP_KERNEL); + if (!events) { + ret = -ENOMEM; + goto e_event_data; + } + + event_descs = kmalloc_array(event_idx + 1, sizeof(*event_descs), + GFP_KERNEL); + if (!event_descs) { + ret = -ENOMEM; + goto e_event_attrs; + } + + event_long_descs = kmalloc_array(event_idx + 1, + sizeof(*event_long_descs), GFP_KERNEL); + if (!event_long_descs) { + ret = -ENOMEM; + goto e_event_descs; + } + + /* Iterate over the catalog filling in the attribute vector */ + for (junk_events = 0, event_attr_ct = 0, desc_ct = 0, long_desc_ct = 0, + event = event_data, event_idx = 0; + event_idx < event_idx_last; + event_idx++, ev_len = be16_to_cpu(event->length), + event = (void *)event + ev_len) { + char *name; + int nl; + int nonce; + /* + * these are the only "bad" events that are intermixed and that + * we can ignore without issue. make sure to skip them here + */ + if (event->event_group_record_len == 0) + continue; + if (!catalog_entry_domain_is_valid(event->domain)) + continue; + + name = event_name(event, &nl); + nonce = event_uniq_add(&ev_uniq, name, nl, event->domain); + ct = event_data_to_attrs(event_idx, events + event_attr_ct, + event, nonce); + if (ct < 0) { + pr_warn("event %zu (%.*s) creation failure, skipping\n", + event_idx, nl, name); + junk_events++; + } else { + event_attr_ct++; + event_descs[desc_ct] = event_to_desc_attr(event, nonce); + if (event_descs[desc_ct]) + desc_ct++; + event_long_descs[long_desc_ct] = + event_to_long_desc_attr(event, nonce); + if (event_long_descs[long_desc_ct]) + long_desc_ct++; + } + } + + pr_info("read %zu catalog entries, created %zu event attrs (%zu failures), %zu descs\n", + event_idx, event_attr_ct, junk_events, desc_ct); + + events[event_attr_ct] = NULL; + event_descs[desc_ct] = NULL; + event_long_descs[long_desc_ct] = NULL; + + event_uniq_destroy(&ev_uniq); + vfree(event_data); + kmem_cache_free(hv_page_cache, page); + + *events_ = events; + *event_descs_ = event_descs; + *event_long_descs_ = event_long_descs; + return 0; + +e_event_descs: + kfree(event_descs); +e_event_attrs: + kfree(events); +e_event_data: + vfree(event_data); +e_free: + kmem_cache_free(hv_page_cache, page); +e_out: + *events_ = NULL; + *event_descs_ = NULL; + *event_long_descs_ = NULL; + return ret; +} + +static ssize_t catalog_read(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, char *buf, + loff_t offset, size_t count) +{ + long hret; + ssize_t ret = 0; + size_t catalog_len = 0, catalog_page_len = 0; + loff_t page_offset = 0; + loff_t offset_in_page; + size_t copy_len; + uint64_t catalog_version_num = 0; + void *page = kmem_cache_alloc(hv_page_cache, GFP_USER); + struct hv_24x7_catalog_page_0 *page_0 = page; + + if (!page) + return -ENOMEM; + + hret = h_get_24x7_catalog_page(page, 0, 0); + if (hret) { + ret = -EIO; + goto e_free; + } + + catalog_version_num = be64_to_cpu(page_0->version); + catalog_page_len = be32_to_cpu(page_0->length); + catalog_len = catalog_page_len * 4096; + + page_offset = offset / 4096; + offset_in_page = offset % 4096; + + if (page_offset >= catalog_page_len) + goto e_free; + + if (page_offset != 0) { + hret = h_get_24x7_catalog_page(page, catalog_version_num, + page_offset); + if (hret) { + ret = -EIO; + goto e_free; + } + } + + copy_len = 4096 - offset_in_page; + if (copy_len > count) + copy_len = count; + + memcpy(buf, page+offset_in_page, copy_len); + ret = copy_len; + +e_free: + if (hret) + pr_err("h_get_24x7_catalog_page(ver=%lld, page=%lld) failed:" + " rc=%ld\n", + catalog_version_num, page_offset, hret); + kmem_cache_free(hv_page_cache, page); + + pr_devel("catalog_read: offset=%lld(%lld) count=%zu " + "catalog_len=%zu(%zu) => %zd\n", offset, page_offset, + count, catalog_len, catalog_page_len, ret); + + return ret; +} + +static ssize_t domains_show(struct device *dev, struct device_attribute *attr, + char *page) +{ + int d, n, count = 0; + const char *str; + + for (d = 0; d < HV_PERF_DOMAIN_MAX; d++) { + str = domain_name(d); + if (!str) + continue; + + n = sprintf(page, "%d: %s\n", d, str); + if (n < 0) + break; + + count += n; + page += n; + } + return count; +} + +#define PAGE_0_ATTR(_name, _fmt, _expr) \ +static ssize_t _name##_show(struct device *dev, \ + struct device_attribute *dev_attr, \ + char *buf) \ +{ \ + long hret; \ + ssize_t ret = 0; \ + void *page = kmem_cache_alloc(hv_page_cache, GFP_USER); \ + struct hv_24x7_catalog_page_0 *page_0 = page; \ + if (!page) \ + return -ENOMEM; \ + hret = h_get_24x7_catalog_page(page, 0, 0); \ + if (hret) { \ + ret = -EIO; \ + goto e_free; \ + } \ + ret = sprintf(buf, _fmt, _expr); \ +e_free: \ + kmem_cache_free(hv_page_cache, page); \ + return ret; \ +} \ +static DEVICE_ATTR_RO(_name) + +PAGE_0_ATTR(catalog_version, "%lld\n", + (unsigned long long)be64_to_cpu(page_0->version)); +PAGE_0_ATTR(catalog_len, "%lld\n", + (unsigned long long)be32_to_cpu(page_0->length) * 4096); +static BIN_ATTR_RO(catalog, 0/* real length varies */); +static DEVICE_ATTR_RO(domains); + +static struct bin_attribute *if_bin_attrs[] = { + &bin_attr_catalog, + NULL, +}; + +static struct attribute *if_attrs[] = { + &dev_attr_catalog_len.attr, + &dev_attr_catalog_version.attr, + &dev_attr_domains.attr, + NULL, +}; + +static struct attribute_group if_group = { + .name = "interface", + .bin_attrs = if_bin_attrs, + .attrs = if_attrs, +}; + +static const struct attribute_group *attr_groups[] = { + &format_group, + &event_group, + &event_desc_group, + &event_long_desc_group, + &if_group, + NULL, +}; + +/* + * Start the process for a new H_GET_24x7_DATA hcall. + */ +static void init_24x7_request(struct hv_24x7_request_buffer *request_buffer, + struct hv_24x7_data_result_buffer *result_buffer) +{ + + memset(request_buffer, 0, H24x7_DATA_BUFFER_SIZE); + memset(result_buffer, 0, H24x7_DATA_BUFFER_SIZE); + + request_buffer->interface_version = interface_version; + /* memset above set request_buffer->num_requests to 0 */ +} + +/* + * Commit (i.e perform) the H_GET_24x7_DATA hcall using the data collected + * by 'init_24x7_request()' and 'add_event_to_24x7_request()'. + */ +static int make_24x7_request(struct hv_24x7_request_buffer *request_buffer, + struct hv_24x7_data_result_buffer *result_buffer) +{ + long ret; + + /* + * NOTE: Due to variable number of array elements in request and + * result buffer(s), sizeof() is not reliable. Use the actual + * allocated buffer size, H24x7_DATA_BUFFER_SIZE. + */ + ret = plpar_hcall_norets(H_GET_24X7_DATA, + virt_to_phys(request_buffer), H24x7_DATA_BUFFER_SIZE, + virt_to_phys(result_buffer), H24x7_DATA_BUFFER_SIZE); + + if (ret) { + struct hv_24x7_request *req; + + req = request_buffer->requests; + pr_notice_ratelimited("hcall failed: [%d %#x %#x %d] => ret 0x%lx (%ld) detail=0x%x failing ix=%x\n", + req->performance_domain, req->data_offset, + req->starting_ix, req->starting_lpar_ix, + ret, ret, result_buffer->detailed_rc, + result_buffer->failing_request_ix); + return -EIO; + } + + return 0; +} + +/* + * Add the given @event to the next slot in the 24x7 request_buffer. + * + * Note that H_GET_24X7_DATA hcall allows reading several counters' + * values in a single HCALL. We expect the caller to add events to the + * request buffer one by one, make the HCALL and process the results. + */ +static int add_event_to_24x7_request(struct perf_event *event, + struct hv_24x7_request_buffer *request_buffer) +{ + u16 idx; + int i; + size_t req_size; + struct hv_24x7_request *req; + + if (request_buffer->num_requests >= + max_num_requests(request_buffer->interface_version)) { + pr_devel("Too many requests for 24x7 HCALL %d\n", + request_buffer->num_requests); + return -EINVAL; + } + + switch (event_get_domain(event)) { + case HV_PERF_DOMAIN_PHYS_CHIP: + idx = event_get_chip(event); + break; + case HV_PERF_DOMAIN_PHYS_CORE: + idx = event_get_core(event); + break; + default: + idx = event_get_vcpu(event); + } + + req_size = H24x7_REQUEST_SIZE(request_buffer->interface_version); + + i = request_buffer->num_requests++; + req = (void *) request_buffer->requests + i * req_size; + + req->performance_domain = event_get_domain(event); + req->data_size = cpu_to_be16(8); + req->data_offset = cpu_to_be32(event_get_offset(event)); + req->starting_lpar_ix = cpu_to_be16(event_get_lpar(event)); + req->max_num_lpars = cpu_to_be16(1); + req->starting_ix = cpu_to_be16(idx); + req->max_ix = cpu_to_be16(1); + + if (request_buffer->interface_version > 1) { + if (domain_needs_aggregation(req->performance_domain)) + req->max_num_thread_groups = -1; + else if (req->performance_domain != HV_PERF_DOMAIN_PHYS_CHIP) { + req->starting_thread_group_ix = idx % 2; + req->max_num_thread_groups = 1; + } + } + + return 0; +} + +/** + * get_count_from_result - get event count from all result elements in result + * + * If the event corresponding to this result needs aggregation of the result + * element values, then this function does that. + * + * @event: Event associated with @res. + * @resb: Result buffer containing @res. + * @res: Result to work on. + * @countp: Output variable containing the event count. + * @next: Optional output variable pointing to the next result in @resb. + */ +static int get_count_from_result(struct perf_event *event, + struct hv_24x7_data_result_buffer *resb, + struct hv_24x7_result *res, u64 *countp, + struct hv_24x7_result **next) +{ + u16 num_elements = be16_to_cpu(res->num_elements_returned); + u16 data_size = be16_to_cpu(res->result_element_data_size); + unsigned int data_offset; + void *element_data; + int i; + u64 count; + + /* + * We can bail out early if the result is empty. + */ + if (!num_elements) { + pr_debug("Result of request %hhu is empty, nothing to do\n", + res->result_ix); + + if (next) + *next = (struct hv_24x7_result *) res->elements; + + return -ENODATA; + } + + /* + * Since we always specify 1 as the maximum for the smallest resource + * we're requesting, there should to be only one element per result. + * Except when an event needs aggregation, in which case there are more. + */ + if (num_elements != 1 && + !domain_needs_aggregation(event_get_domain(event))) { + pr_err("Error: result of request %hhu has %hu elements\n", + res->result_ix, num_elements); + + return -EIO; + } + + if (data_size != sizeof(u64)) { + pr_debug("Error: result of request %hhu has data of %hu bytes\n", + res->result_ix, data_size); + + return -ENOTSUPP; + } + + if (resb->interface_version == 1) + data_offset = offsetof(struct hv_24x7_result_element_v1, + element_data); + else + data_offset = offsetof(struct hv_24x7_result_element_v2, + element_data); + + /* Go through the result elements in the result. */ + for (i = count = 0, element_data = res->elements + data_offset; + i < num_elements; + i++, element_data += data_size + data_offset) + count += be64_to_cpu(*((u64 *) element_data)); + + *countp = count; + + /* The next result is after the last result element. */ + if (next) + *next = element_data - data_offset; + + return 0; +} + +static int single_24x7_request(struct perf_event *event, u64 *count) +{ + int ret; + struct hv_24x7_request_buffer *request_buffer; + struct hv_24x7_data_result_buffer *result_buffer; + + BUILD_BUG_ON(sizeof(*request_buffer) > 4096); + BUILD_BUG_ON(sizeof(*result_buffer) > 4096); + + request_buffer = (void *)get_cpu_var(hv_24x7_reqb); + result_buffer = (void *)get_cpu_var(hv_24x7_resb); + + init_24x7_request(request_buffer, result_buffer); + + ret = add_event_to_24x7_request(event, request_buffer); + if (ret) + goto out; + + ret = make_24x7_request(request_buffer, result_buffer); + if (ret) + goto out; + + /* process result from hcall */ + ret = get_count_from_result(event, result_buffer, + result_buffer->results, count, NULL); + +out: + put_cpu_var(hv_24x7_reqb); + put_cpu_var(hv_24x7_resb); + return ret; +} + + +static int h_24x7_event_init(struct perf_event *event) +{ + struct hv_perf_caps caps; + unsigned domain; + unsigned long hret; + u64 ct; + + /* Not our event */ + if (event->attr.type != event->pmu->type) + return -ENOENT; + + /* Unused areas must be 0 */ + if (event_get_reserved1(event) || + event_get_reserved2(event) || + event_get_reserved3(event)) { + pr_devel("reserved set when forbidden 0x%llx(0x%llx) 0x%llx(0x%llx) 0x%llx(0x%llx)\n", + event->attr.config, + event_get_reserved1(event), + event->attr.config1, + event_get_reserved2(event), + event->attr.config2, + event_get_reserved3(event)); + return -EINVAL; + } + + /* unsupported modes and filters */ + if (event->attr.exclude_user || + event->attr.exclude_kernel || + event->attr.exclude_hv || + event->attr.exclude_idle || + event->attr.exclude_host || + event->attr.exclude_guest) + return -EINVAL; + + /* no branch sampling */ + if (has_branch_stack(event)) + return -EOPNOTSUPP; + + /* offset must be 8 byte aligned */ + if (event_get_offset(event) % 8) { + pr_devel("bad alignment\n"); + return -EINVAL; + } + + domain = event_get_domain(event); + if (domain >= HV_PERF_DOMAIN_MAX) { + pr_devel("invalid domain %d\n", domain); + return -EINVAL; + } + + hret = hv_perf_caps_get(&caps); + if (hret) { + pr_devel("could not get capabilities: rc=%ld\n", hret); + return -EIO; + } + + /* Physical domains & other lpars require extra capabilities */ + if (!caps.collect_privileged && (is_physical_domain(domain) || + (event_get_lpar(event) != event_get_lpar_max()))) { + pr_devel("hv permissions disallow: is_physical_domain:%d, lpar=0x%llx\n", + is_physical_domain(domain), + event_get_lpar(event)); + return -EACCES; + } + + /* Get the initial value of the counter for this event */ + if (single_24x7_request(event, &ct)) { + pr_devel("test hcall failed\n"); + return -EIO; + } + (void)local64_xchg(&event->hw.prev_count, ct); + + return 0; +} + +static u64 h_24x7_get_value(struct perf_event *event) +{ + u64 ct; + + if (single_24x7_request(event, &ct)) + /* We checked this in event init, shouldn't fail here... */ + return 0; + + return ct; +} + +static void update_event_count(struct perf_event *event, u64 now) +{ + s64 prev; + + prev = local64_xchg(&event->hw.prev_count, now); + local64_add(now - prev, &event->count); +} + +static void h_24x7_event_read(struct perf_event *event) +{ + u64 now; + struct hv_24x7_request_buffer *request_buffer; + struct hv_24x7_hw *h24x7hw; + int txn_flags; + + txn_flags = __this_cpu_read(hv_24x7_txn_flags); + + /* + * If in a READ transaction, add this counter to the list of + * counters to read during the next HCALL (i.e commit_txn()). + * If not in a READ transaction, go ahead and make the HCALL + * to read this counter by itself. + */ + + if (txn_flags & PERF_PMU_TXN_READ) { + int i; + int ret; + + if (__this_cpu_read(hv_24x7_txn_err)) + return; + + request_buffer = (void *)get_cpu_var(hv_24x7_reqb); + + ret = add_event_to_24x7_request(event, request_buffer); + if (ret) { + __this_cpu_write(hv_24x7_txn_err, ret); + } else { + /* + * Associate the event with the HCALL request index, + * so ->commit_txn() can quickly find/update count. + */ + i = request_buffer->num_requests - 1; + + h24x7hw = &get_cpu_var(hv_24x7_hw); + h24x7hw->events[i] = event; + put_cpu_var(h24x7hw); + } + + put_cpu_var(hv_24x7_reqb); + } else { + now = h_24x7_get_value(event); + update_event_count(event, now); + } +} + +static void h_24x7_event_start(struct perf_event *event, int flags) +{ + if (flags & PERF_EF_RELOAD) + local64_set(&event->hw.prev_count, h_24x7_get_value(event)); +} + +static void h_24x7_event_stop(struct perf_event *event, int flags) +{ + h_24x7_event_read(event); +} + +static int h_24x7_event_add(struct perf_event *event, int flags) +{ + if (flags & PERF_EF_START) + h_24x7_event_start(event, flags); + + return 0; +} + +/* + * 24x7 counters only support READ transactions. They are + * always counting and dont need/support ADD transactions. + * Cache the flags, but otherwise ignore transactions that + * are not PERF_PMU_TXN_READ. + */ +static void h_24x7_event_start_txn(struct pmu *pmu, unsigned int flags) +{ + struct hv_24x7_request_buffer *request_buffer; + struct hv_24x7_data_result_buffer *result_buffer; + + /* We should not be called if we are already in a txn */ + WARN_ON_ONCE(__this_cpu_read(hv_24x7_txn_flags)); + + __this_cpu_write(hv_24x7_txn_flags, flags); + if (flags & ~PERF_PMU_TXN_READ) + return; + + request_buffer = (void *)get_cpu_var(hv_24x7_reqb); + result_buffer = (void *)get_cpu_var(hv_24x7_resb); + + init_24x7_request(request_buffer, result_buffer); + + put_cpu_var(hv_24x7_resb); + put_cpu_var(hv_24x7_reqb); +} + +/* + * Clean up transaction state. + * + * NOTE: Ignore state of request and result buffers for now. + * We will initialize them during the next read/txn. + */ +static void reset_txn(void) +{ + __this_cpu_write(hv_24x7_txn_flags, 0); + __this_cpu_write(hv_24x7_txn_err, 0); +} + +/* + * 24x7 counters only support READ transactions. They are always counting + * and dont need/support ADD transactions. Clear ->txn_flags but otherwise + * ignore transactions that are not of type PERF_PMU_TXN_READ. + * + * For READ transactions, submit all pending 24x7 requests (i.e requests + * that were queued by h_24x7_event_read()), to the hypervisor and update + * the event counts. + */ +static int h_24x7_event_commit_txn(struct pmu *pmu) +{ + struct hv_24x7_request_buffer *request_buffer; + struct hv_24x7_data_result_buffer *result_buffer; + struct hv_24x7_result *res, *next_res; + u64 count; + int i, ret, txn_flags; + struct hv_24x7_hw *h24x7hw; + + txn_flags = __this_cpu_read(hv_24x7_txn_flags); + WARN_ON_ONCE(!txn_flags); + + ret = 0; + if (txn_flags & ~PERF_PMU_TXN_READ) + goto out; + + ret = __this_cpu_read(hv_24x7_txn_err); + if (ret) + goto out; + + request_buffer = (void *)get_cpu_var(hv_24x7_reqb); + result_buffer = (void *)get_cpu_var(hv_24x7_resb); + + ret = make_24x7_request(request_buffer, result_buffer); + if (ret) + goto put_reqb; + + h24x7hw = &get_cpu_var(hv_24x7_hw); + + /* Go through results in the result buffer to update event counts. */ + for (i = 0, res = result_buffer->results; + i < result_buffer->num_results; i++, res = next_res) { + struct perf_event *event = h24x7hw->events[res->result_ix]; + + ret = get_count_from_result(event, result_buffer, res, &count, + &next_res); + if (ret) + break; + + update_event_count(event, count); + } + + put_cpu_var(hv_24x7_hw); + +put_reqb: + put_cpu_var(hv_24x7_resb); + put_cpu_var(hv_24x7_reqb); +out: + reset_txn(); + return ret; +} + +/* + * 24x7 counters only support READ transactions. They are always counting + * and dont need/support ADD transactions. However, regardless of type + * of transaction, all we need to do is cleanup, so we don't have to check + * the type of transaction. + */ +static void h_24x7_event_cancel_txn(struct pmu *pmu) +{ + WARN_ON_ONCE(!__this_cpu_read(hv_24x7_txn_flags)); + reset_txn(); +} + +static struct pmu h_24x7_pmu = { + .task_ctx_nr = perf_invalid_context, + + .name = "hv_24x7", + .attr_groups = attr_groups, + .event_init = h_24x7_event_init, + .add = h_24x7_event_add, + .del = h_24x7_event_stop, + .start = h_24x7_event_start, + .stop = h_24x7_event_stop, + .read = h_24x7_event_read, + .start_txn = h_24x7_event_start_txn, + .commit_txn = h_24x7_event_commit_txn, + .cancel_txn = h_24x7_event_cancel_txn, +}; + +static int hv_24x7_init(void) +{ + int r; + unsigned long hret; + struct hv_perf_caps caps; + + if (!firmware_has_feature(FW_FEATURE_LPAR)) { + pr_debug("not a virtualized system, not enabling\n"); + return -ENODEV; + } else if (!cur_cpu_spec->oprofile_cpu_type) + return -ENODEV; + + /* POWER8 only supports v1, while POWER9 only supports v2. */ + if (!strcmp(cur_cpu_spec->oprofile_cpu_type, "ppc64/power8")) + interface_version = 1; + else { + interface_version = 2; + + /* SMT8 in POWER9 needs to aggregate result elements. */ + if (threads_per_core == 8) + aggregate_result_elements = true; + } + + hret = hv_perf_caps_get(&caps); + if (hret) { + pr_debug("could not obtain capabilities, not enabling, rc=%ld\n", + hret); + return -ENODEV; + } + + hv_page_cache = kmem_cache_create("hv-page-4096", 4096, 4096, 0, NULL); + if (!hv_page_cache) + return -ENOMEM; + + /* sampling not supported */ + h_24x7_pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT; + + r = create_events_from_catalog(&event_group.attrs, + &event_desc_group.attrs, + &event_long_desc_group.attrs); + + if (r) + return r; + + r = perf_pmu_register(&h_24x7_pmu, h_24x7_pmu.name, -1); + if (r) + return r; + + return 0; +} + +device_initcall(hv_24x7_init); |