linux_dsm_epyc7002/tools/perf/util/evsel.c
Andrew Vagin 3e76ac78b0 perf record: Add ability to record event period
The problem is that when SAMPLE_PERIOD is not set, the kernel generates
a number of samples in proportion to an event's period. Number of these
samples may be too big and the kernel throttles all samples above a
defined limit.

E.g.: I want to trace when a process sleeps. I created a process which
sleeps for 1ms and for 4ms.  perf got 100 events in both cases.

swapper 0 [000] 1141.371830: sched_stat_sleep: comm=foo pid=1801 delay=1386750 [ns]
swapper 0 [000] 1141.369444: sched_stat_sleep: comm=foo pid=1801 delay=4499585 [ns]

In the first case a kernel want to send 4499585 events and in the second
case it wants to send 1386750 events.  perf-reports shows that process
sleeps in both places equal time.

Instead of this we can get only one sample with an attribute period. As
result we have less data transferring between kernel and user-space and
we avoid throttling of samples.

The patch "events: Don't divide events if it has field period" added a
kernel part of this functionality.

Acked-by: Arun Sharma <asharma@fb.com>
Cc: Arun Sharma <asharma@fb.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: devel@openvz.org
Link: http://lkml.kernel.org/r/1324391565-1369947-1-git-send-email-avagin@openvz.org
Signed-off-by: Andrew Vagin <avagin@openvz.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-12-20 12:50:09 -02:00

659 lines
14 KiB
C

/*
* Copyright (C) 2011, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
*
* Parts came from builtin-{top,stat,record}.c, see those files for further
* copyright notes.
*
* Released under the GPL v2. (and only v2, not any later version)
*/
#include <byteswap.h>
#include "asm/bug.h"
#include "evsel.h"
#include "evlist.h"
#include "util.h"
#include "cpumap.h"
#include "thread_map.h"
#define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
#define GROUP_FD(group_fd, cpu) (*(int *)xyarray__entry(group_fd, cpu, 0))
int __perf_evsel__sample_size(u64 sample_type)
{
u64 mask = sample_type & PERF_SAMPLE_MASK;
int size = 0;
int i;
for (i = 0; i < 64; i++) {
if (mask & (1ULL << i))
size++;
}
size *= sizeof(u64);
return size;
}
static void hists__init(struct hists *hists)
{
memset(hists, 0, sizeof(*hists));
hists->entries_in_array[0] = hists->entries_in_array[1] = RB_ROOT;
hists->entries_in = &hists->entries_in_array[0];
hists->entries_collapsed = RB_ROOT;
hists->entries = RB_ROOT;
pthread_mutex_init(&hists->lock, NULL);
}
void perf_evsel__init(struct perf_evsel *evsel,
struct perf_event_attr *attr, int idx)
{
evsel->idx = idx;
evsel->attr = *attr;
INIT_LIST_HEAD(&evsel->node);
hists__init(&evsel->hists);
}
struct perf_evsel *perf_evsel__new(struct perf_event_attr *attr, int idx)
{
struct perf_evsel *evsel = zalloc(sizeof(*evsel));
if (evsel != NULL)
perf_evsel__init(evsel, attr, idx);
return evsel;
}
void perf_evsel__config(struct perf_evsel *evsel, struct perf_record_opts *opts)
{
struct perf_event_attr *attr = &evsel->attr;
int track = !evsel->idx; /* only the first counter needs these */
attr->sample_id_all = opts->sample_id_all_avail ? 1 : 0;
attr->inherit = !opts->no_inherit;
attr->read_format = PERF_FORMAT_TOTAL_TIME_ENABLED |
PERF_FORMAT_TOTAL_TIME_RUNNING |
PERF_FORMAT_ID;
attr->sample_type |= PERF_SAMPLE_IP | PERF_SAMPLE_TID;
/*
* We default some events to a 1 default interval. But keep
* it a weak assumption overridable by the user.
*/
if (!attr->sample_period || (opts->user_freq != UINT_MAX &&
opts->user_interval != ULLONG_MAX)) {
if (opts->freq) {
attr->sample_type |= PERF_SAMPLE_PERIOD;
attr->freq = 1;
attr->sample_freq = opts->freq;
} else {
attr->sample_period = opts->default_interval;
}
}
if (opts->no_samples)
attr->sample_freq = 0;
if (opts->inherit_stat)
attr->inherit_stat = 1;
if (opts->sample_address) {
attr->sample_type |= PERF_SAMPLE_ADDR;
attr->mmap_data = track;
}
if (opts->call_graph)
attr->sample_type |= PERF_SAMPLE_CALLCHAIN;
if (opts->system_wide)
attr->sample_type |= PERF_SAMPLE_CPU;
if (opts->period)
attr->sample_type |= PERF_SAMPLE_PERIOD;
if (opts->sample_id_all_avail &&
(opts->sample_time || opts->system_wide ||
!opts->no_inherit || opts->cpu_list))
attr->sample_type |= PERF_SAMPLE_TIME;
if (opts->raw_samples) {
attr->sample_type |= PERF_SAMPLE_TIME;
attr->sample_type |= PERF_SAMPLE_RAW;
attr->sample_type |= PERF_SAMPLE_CPU;
}
if (opts->no_delay) {
attr->watermark = 0;
attr->wakeup_events = 1;
}
attr->mmap = track;
attr->comm = track;
if (opts->target_pid == -1 && opts->target_tid == -1 && !opts->system_wide) {
attr->disabled = 1;
attr->enable_on_exec = 1;
}
}
int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
{
int cpu, thread;
evsel->fd = xyarray__new(ncpus, nthreads, sizeof(int));
if (evsel->fd) {
for (cpu = 0; cpu < ncpus; cpu++) {
for (thread = 0; thread < nthreads; thread++) {
FD(evsel, cpu, thread) = -1;
}
}
}
return evsel->fd != NULL ? 0 : -ENOMEM;
}
int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads)
{
evsel->sample_id = xyarray__new(ncpus, nthreads, sizeof(struct perf_sample_id));
if (evsel->sample_id == NULL)
return -ENOMEM;
evsel->id = zalloc(ncpus * nthreads * sizeof(u64));
if (evsel->id == NULL) {
xyarray__delete(evsel->sample_id);
evsel->sample_id = NULL;
return -ENOMEM;
}
return 0;
}
int perf_evsel__alloc_counts(struct perf_evsel *evsel, int ncpus)
{
evsel->counts = zalloc((sizeof(*evsel->counts) +
(ncpus * sizeof(struct perf_counts_values))));
return evsel->counts != NULL ? 0 : -ENOMEM;
}
void perf_evsel__free_fd(struct perf_evsel *evsel)
{
xyarray__delete(evsel->fd);
evsel->fd = NULL;
}
void perf_evsel__free_id(struct perf_evsel *evsel)
{
xyarray__delete(evsel->sample_id);
evsel->sample_id = NULL;
free(evsel->id);
evsel->id = NULL;
}
void perf_evsel__close_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
{
int cpu, thread;
for (cpu = 0; cpu < ncpus; cpu++)
for (thread = 0; thread < nthreads; ++thread) {
close(FD(evsel, cpu, thread));
FD(evsel, cpu, thread) = -1;
}
}
void perf_evsel__exit(struct perf_evsel *evsel)
{
assert(list_empty(&evsel->node));
xyarray__delete(evsel->fd);
xyarray__delete(evsel->sample_id);
free(evsel->id);
}
void perf_evsel__delete(struct perf_evsel *evsel)
{
perf_evsel__exit(evsel);
close_cgroup(evsel->cgrp);
free(evsel->name);
free(evsel);
}
int __perf_evsel__read_on_cpu(struct perf_evsel *evsel,
int cpu, int thread, bool scale)
{
struct perf_counts_values count;
size_t nv = scale ? 3 : 1;
if (FD(evsel, cpu, thread) < 0)
return -EINVAL;
if (evsel->counts == NULL && perf_evsel__alloc_counts(evsel, cpu + 1) < 0)
return -ENOMEM;
if (readn(FD(evsel, cpu, thread), &count, nv * sizeof(u64)) < 0)
return -errno;
if (scale) {
if (count.run == 0)
count.val = 0;
else if (count.run < count.ena)
count.val = (u64)((double)count.val * count.ena / count.run + 0.5);
} else
count.ena = count.run = 0;
evsel->counts->cpu[cpu] = count;
return 0;
}
int __perf_evsel__read(struct perf_evsel *evsel,
int ncpus, int nthreads, bool scale)
{
size_t nv = scale ? 3 : 1;
int cpu, thread;
struct perf_counts_values *aggr = &evsel->counts->aggr, count;
aggr->val = aggr->ena = aggr->run = 0;
for (cpu = 0; cpu < ncpus; cpu++) {
for (thread = 0; thread < nthreads; thread++) {
if (FD(evsel, cpu, thread) < 0)
continue;
if (readn(FD(evsel, cpu, thread),
&count, nv * sizeof(u64)) < 0)
return -errno;
aggr->val += count.val;
if (scale) {
aggr->ena += count.ena;
aggr->run += count.run;
}
}
}
evsel->counts->scaled = 0;
if (scale) {
if (aggr->run == 0) {
evsel->counts->scaled = -1;
aggr->val = 0;
return 0;
}
if (aggr->run < aggr->ena) {
evsel->counts->scaled = 1;
aggr->val = (u64)((double)aggr->val * aggr->ena / aggr->run + 0.5);
}
} else
aggr->ena = aggr->run = 0;
return 0;
}
static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
struct thread_map *threads, bool group,
struct xyarray *group_fds)
{
int cpu, thread;
unsigned long flags = 0;
int pid = -1, err;
if (evsel->fd == NULL &&
perf_evsel__alloc_fd(evsel, cpus->nr, threads->nr) < 0)
return -ENOMEM;
if (evsel->cgrp) {
flags = PERF_FLAG_PID_CGROUP;
pid = evsel->cgrp->fd;
}
for (cpu = 0; cpu < cpus->nr; cpu++) {
int group_fd = group_fds ? GROUP_FD(group_fds, cpu) : -1;
for (thread = 0; thread < threads->nr; thread++) {
if (!evsel->cgrp)
pid = threads->map[thread];
FD(evsel, cpu, thread) = sys_perf_event_open(&evsel->attr,
pid,
cpus->map[cpu],
group_fd, flags);
if (FD(evsel, cpu, thread) < 0) {
err = -errno;
goto out_close;
}
if (group && group_fd == -1)
group_fd = FD(evsel, cpu, thread);
}
}
return 0;
out_close:
do {
while (--thread >= 0) {
close(FD(evsel, cpu, thread));
FD(evsel, cpu, thread) = -1;
}
thread = threads->nr;
} while (--cpu >= 0);
return err;
}
void perf_evsel__close(struct perf_evsel *evsel, int ncpus, int nthreads)
{
if (evsel->fd == NULL)
return;
perf_evsel__close_fd(evsel, ncpus, nthreads);
perf_evsel__free_fd(evsel);
evsel->fd = NULL;
}
static struct {
struct cpu_map map;
int cpus[1];
} empty_cpu_map = {
.map.nr = 1,
.cpus = { -1, },
};
static struct {
struct thread_map map;
int threads[1];
} empty_thread_map = {
.map.nr = 1,
.threads = { -1, },
};
int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
struct thread_map *threads, bool group,
struct xyarray *group_fd)
{
if (cpus == NULL) {
/* Work around old compiler warnings about strict aliasing */
cpus = &empty_cpu_map.map;
}
if (threads == NULL)
threads = &empty_thread_map.map;
return __perf_evsel__open(evsel, cpus, threads, group, group_fd);
}
int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
struct cpu_map *cpus, bool group,
struct xyarray *group_fd)
{
return __perf_evsel__open(evsel, cpus, &empty_thread_map.map, group,
group_fd);
}
int perf_evsel__open_per_thread(struct perf_evsel *evsel,
struct thread_map *threads, bool group,
struct xyarray *group_fd)
{
return __perf_evsel__open(evsel, &empty_cpu_map.map, threads, group,
group_fd);
}
static int perf_event__parse_id_sample(const union perf_event *event, u64 type,
struct perf_sample *sample)
{
const u64 *array = event->sample.array;
array += ((event->header.size -
sizeof(event->header)) / sizeof(u64)) - 1;
if (type & PERF_SAMPLE_CPU) {
u32 *p = (u32 *)array;
sample->cpu = *p;
array--;
}
if (type & PERF_SAMPLE_STREAM_ID) {
sample->stream_id = *array;
array--;
}
if (type & PERF_SAMPLE_ID) {
sample->id = *array;
array--;
}
if (type & PERF_SAMPLE_TIME) {
sample->time = *array;
array--;
}
if (type & PERF_SAMPLE_TID) {
u32 *p = (u32 *)array;
sample->pid = p[0];
sample->tid = p[1];
}
return 0;
}
static bool sample_overlap(const union perf_event *event,
const void *offset, u64 size)
{
const void *base = event;
if (offset + size > base + event->header.size)
return true;
return false;
}
int perf_event__parse_sample(const union perf_event *event, u64 type,
int sample_size, bool sample_id_all,
struct perf_sample *data, bool swapped)
{
const u64 *array;
/*
* used for cross-endian analysis. See git commit 65014ab3
* for why this goofiness is needed.
*/
union {
u64 val64;
u32 val32[2];
} u;
data->cpu = data->pid = data->tid = -1;
data->stream_id = data->id = data->time = -1ULL;
if (event->header.type != PERF_RECORD_SAMPLE) {
if (!sample_id_all)
return 0;
return perf_event__parse_id_sample(event, type, data);
}
array = event->sample.array;
if (sample_size + sizeof(event->header) > event->header.size)
return -EFAULT;
if (type & PERF_SAMPLE_IP) {
data->ip = event->ip.ip;
array++;
}
if (type & PERF_SAMPLE_TID) {
u.val64 = *array;
if (swapped) {
/* undo swap of u64, then swap on individual u32s */
u.val64 = bswap_64(u.val64);
u.val32[0] = bswap_32(u.val32[0]);
u.val32[1] = bswap_32(u.val32[1]);
}
data->pid = u.val32[0];
data->tid = u.val32[1];
array++;
}
if (type & PERF_SAMPLE_TIME) {
data->time = *array;
array++;
}
data->addr = 0;
if (type & PERF_SAMPLE_ADDR) {
data->addr = *array;
array++;
}
data->id = -1ULL;
if (type & PERF_SAMPLE_ID) {
data->id = *array;
array++;
}
if (type & PERF_SAMPLE_STREAM_ID) {
data->stream_id = *array;
array++;
}
if (type & PERF_SAMPLE_CPU) {
u.val64 = *array;
if (swapped) {
/* undo swap of u64, then swap on individual u32s */
u.val64 = bswap_64(u.val64);
u.val32[0] = bswap_32(u.val32[0]);
}
data->cpu = u.val32[0];
array++;
}
if (type & PERF_SAMPLE_PERIOD) {
data->period = *array;
array++;
}
if (type & PERF_SAMPLE_READ) {
fprintf(stderr, "PERF_SAMPLE_READ is unsuported for now\n");
return -1;
}
if (type & PERF_SAMPLE_CALLCHAIN) {
if (sample_overlap(event, array, sizeof(data->callchain->nr)))
return -EFAULT;
data->callchain = (struct ip_callchain *)array;
if (sample_overlap(event, array, data->callchain->nr))
return -EFAULT;
array += 1 + data->callchain->nr;
}
if (type & PERF_SAMPLE_RAW) {
const u64 *pdata;
u.val64 = *array;
if (WARN_ONCE(swapped,
"Endianness of raw data not corrected!\n")) {
/* undo swap of u64, then swap on individual u32s */
u.val64 = bswap_64(u.val64);
u.val32[0] = bswap_32(u.val32[0]);
u.val32[1] = bswap_32(u.val32[1]);
}
if (sample_overlap(event, array, sizeof(u32)))
return -EFAULT;
data->raw_size = u.val32[0];
pdata = (void *) array + sizeof(u32);
if (sample_overlap(event, pdata, data->raw_size))
return -EFAULT;
data->raw_data = (void *) pdata;
}
return 0;
}
int perf_event__synthesize_sample(union perf_event *event, u64 type,
const struct perf_sample *sample,
bool swapped)
{
u64 *array;
/*
* used for cross-endian analysis. See git commit 65014ab3
* for why this goofiness is needed.
*/
union {
u64 val64;
u32 val32[2];
} u;
array = event->sample.array;
if (type & PERF_SAMPLE_IP) {
event->ip.ip = sample->ip;
array++;
}
if (type & PERF_SAMPLE_TID) {
u.val32[0] = sample->pid;
u.val32[1] = sample->tid;
if (swapped) {
/*
* Inverse of what is done in perf_event__parse_sample
*/
u.val32[0] = bswap_32(u.val32[0]);
u.val32[1] = bswap_32(u.val32[1]);
u.val64 = bswap_64(u.val64);
}
*array = u.val64;
array++;
}
if (type & PERF_SAMPLE_TIME) {
*array = sample->time;
array++;
}
if (type & PERF_SAMPLE_ADDR) {
*array = sample->addr;
array++;
}
if (type & PERF_SAMPLE_ID) {
*array = sample->id;
array++;
}
if (type & PERF_SAMPLE_STREAM_ID) {
*array = sample->stream_id;
array++;
}
if (type & PERF_SAMPLE_CPU) {
u.val32[0] = sample->cpu;
if (swapped) {
/*
* Inverse of what is done in perf_event__parse_sample
*/
u.val32[0] = bswap_32(u.val32[0]);
u.val64 = bswap_64(u.val64);
}
*array = u.val64;
array++;
}
if (type & PERF_SAMPLE_PERIOD) {
*array = sample->period;
array++;
}
return 0;
}