linux/tools/perf/util/evsel.c
Naveen N. Rao a4a03fc7ef perf evsel: Fix an issue where perf report fails to show the proper percentage
This patch fixes an issue where perf report shows nan% for certain
perf.data files. The below is from a report for a do_fork probe:

   -nan%           sshd  [kernel.kallsyms]  [k] do_fork
   -nan%    packagekitd  [kernel.kallsyms]  [k] do_fork
   -nan%    dbus-daemon  [kernel.kallsyms]  [k] do_fork
   -nan%           bash  [kernel.kallsyms]  [k] do_fork

A git bisect shows commit f3bda2c as the cause. However, looking back
through the git history, I saw commit 640c03c which seems to have
removed the required initialization for perf_sample->period. The problem
only started showing after commit f3bda2c. The below patch re-introduces
the initialization and it fixes the problem for me.

With the below patch, for the same perf.data:

  73.08%             bash  [kernel.kallsyms]  [k] do_fork
   8.97%      11-dhclient  [kernel.kallsyms]  [k] do_fork
   6.41%             sshd  [kernel.kallsyms]  [k] do_fork
   3.85%        20-chrony  [kernel.kallsyms]  [k] do_fork
   2.56%         sendmail  [kernel.kallsyms]  [k] do_fork

This patch applies over current linux-tip commit 9949284.

Problem introduced in:

$ git describe 640c03c
v2.6.37-rc3-83-g640c03c

Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: stable@kernel.org
Link: http://lkml.kernel.org/r/20120203170113.5190.25558.stgit@localhost6.localdomain6
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-02-06 18:59:38 -02:00

660 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;
memset(data, 0, sizeof(*data));
data->cpu = data->pid = data->tid = -1;
data->stream_id = data->id = data->time = -1ULL;
data->period = 1;
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;
}