perf evsel: Introduce per cpu and per thread open helpers

Abstracting away the loops needed to create the various event fd handlers.

The users have to pass a confiruged perf->evsel.attr field, which is already
usable after perf_evsel__new (constructor) time, using defaults.

Comes out of the ad-hoc routines in builtin-stat, that now uses it.

Fixed a small silly bug where we were die()ing before killing our
children, dysfunctional family this one 8-)

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Arnaldo Carvalho de Melo 2011-01-03 17:48:12 -02:00
parent c52b12ed25
commit 48290609c0
3 changed files with 82 additions and 57 deletions

View File

@ -53,8 +53,6 @@
#include <math.h>
#include <locale.h>
#define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
#define DEFAULT_SEPARATOR " "
static struct perf_event_attr default_attrs[] = {
@ -160,56 +158,24 @@ struct stats runtime_cycles_stats[MAX_NR_CPUS];
struct stats runtime_branches_stats[MAX_NR_CPUS];
struct stats walltime_nsecs_stats;
#define ERR_PERF_OPEN \
"counter %d, sys_perf_event_open() syscall returned with %d (%s). /bin/dmesg may provide additional information."
static int create_perf_stat_counter(struct perf_evsel *evsel, bool *perm_err)
static int create_perf_stat_counter(struct perf_evsel *evsel)
{
struct perf_event_attr *attr = &evsel->attr;
int thread;
int ncreated = 0;
if (scale)
attr->read_format = PERF_FORMAT_TOTAL_TIME_ENABLED |
PERF_FORMAT_TOTAL_TIME_RUNNING;
if (system_wide) {
int cpu;
if (system_wide)
return perf_evsel__open_per_cpu(evsel, nr_cpus, cpumap);
for (cpu = 0; cpu < nr_cpus; cpu++) {
FD(evsel, cpu, 0) = sys_perf_event_open(attr,
-1, cpumap[cpu], -1, 0);
if (FD(evsel, cpu, 0) < 0) {
if (errno == EPERM || errno == EACCES)
*perm_err = true;
error(ERR_PERF_OPEN, evsel->idx,
FD(evsel, cpu, 0), strerror(errno));
} else {
++ncreated;
}
}
} else {
attr->inherit = !no_inherit;
if (target_pid == -1 && target_tid == -1) {
attr->disabled = 1;
attr->enable_on_exec = 1;
}
for (thread = 0; thread < thread_num; thread++) {
FD(evsel, 0, thread) = sys_perf_event_open(attr,
all_tids[thread], -1, -1, 0);
if (FD(evsel, 0, thread) < 0) {
if (errno == EPERM || errno == EACCES)
*perm_err = true;
error(ERR_PERF_OPEN, evsel->idx,
FD(evsel, 0, thread),
strerror(errno));
} else {
++ncreated;
}
}
attr->inherit = !no_inherit;
if (target_pid == -1 && target_tid == -1) {
attr->disabled = 1;
attr->enable_on_exec = 1;
}
return ncreated;
return perf_evsel__open_per_thread(evsel, thread_num, all_tids);
}
/*
@ -289,9 +255,7 @@ static int run_perf_stat(int argc __used, const char **argv)
unsigned long long t0, t1;
struct perf_evsel *counter;
int status = 0;
int ncreated = 0;
int child_ready_pipe[2], go_pipe[2];
bool perm_err = false;
const bool forks = (argc > 0);
char buf;
@ -349,19 +313,23 @@ static int run_perf_stat(int argc __used, const char **argv)
close(child_ready_pipe[0]);
}
list_for_each_entry(counter, &evsel_list, node)
ncreated += create_perf_stat_counter(counter, &perm_err);
if (ncreated < nr_counters) {
if (perm_err)
error("You may not have permission to collect %sstats.\n"
"\t Consider tweaking"
" /proc/sys/kernel/perf_event_paranoid or running as root.",
system_wide ? "system-wide " : "");
die("Not all events could be opened.\n");
if (child_pid != -1)
kill(child_pid, SIGTERM);
return -1;
list_for_each_entry(counter, &evsel_list, node) {
if (create_perf_stat_counter(counter) < 0) {
if (errno == -EPERM || errno == -EACCES) {
error("You may not have permission to collect %sstats.\n"
"\t Consider tweaking"
" /proc/sys/kernel/perf_event_paranoid or running as root.",
system_wide ? "system-wide " : "");
} else {
error("open_counter returned with %d (%s). "
"/bin/dmesg may provide additional information.\n",
errno, strerror(errno));
}
if (child_pid != -1)
kill(child_pid, SIGTERM);
die("Not all events could be opened.\n");
return -1;
}
}
/*

View File

@ -1,4 +1,5 @@
#include "evsel.h"
#include "../perf.h"
#include "util.h"
#define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
@ -121,3 +122,54 @@ int __perf_evsel__read(struct perf_evsel *evsel,
return 0;
}
int perf_evsel__open_per_cpu(struct perf_evsel *evsel, int ncpus, int *cpu_map)
{
int cpu;
for (cpu = 0; cpu < ncpus; cpu++) {
FD(evsel, cpu, 0) = sys_perf_event_open(&evsel->attr, -1,
cpu_map[cpu], -1, 0);
if (FD(evsel, cpu, 0) < 0)
goto out_close;
}
return 0;
out_close:
while (--cpu >= 0) {
close(FD(evsel, cpu, 0));
FD(evsel, cpu, 0) = -1;
}
return -1;
}
int perf_evsel__open_per_thread(struct perf_evsel *evsel, int nthreads, int *thread_map)
{
int thread;
for (thread = 0; thread < nthreads; thread++) {
FD(evsel, 0, thread) = sys_perf_event_open(&evsel->attr,
thread_map[thread], -1, -1, 0);
if (FD(evsel, 0, thread) < 0)
goto out_close;
}
return 0;
out_close:
while (--thread >= 0) {
close(FD(evsel, 0, thread));
FD(evsel, 0, thread) = -1;
}
return -1;
}
int perf_evsel__open(struct perf_evsel *evsel, int ncpus, int nthreads,
int *cpu_map, int *thread_map)
{
if (nthreads < 0)
return perf_evsel__open_per_cpu(evsel, ncpus, cpu_map);
return perf_evsel__open_per_thread(evsel, nthreads, thread_map);
}

View File

@ -42,6 +42,11 @@ int perf_evsel__alloc_counts(struct perf_evsel *evsel, int ncpus);
void perf_evsel__free_fd(struct perf_evsel *evsel);
void perf_evsel__close_fd(struct perf_evsel *evsel, int ncpus, int nthreads);
int perf_evsel__open_per_cpu(struct perf_evsel *evsel, int ncpus, int *cpu_map);
int perf_evsel__open_per_thread(struct perf_evsel *evsel, int nthreads, int *thread_map);
int perf_evsel__open(struct perf_evsel *evsel, int ncpus, int nthreads,
int *cpu_map, int *thread_map);
#define perf_evsel__match(evsel, t, c) \
(evsel->attr.type == PERF_TYPE_##t && \
evsel->attr.config == PERF_COUNT_##c)