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linux-2.6/Documentation/perf_counter/builtin-stat.c

355 lines
8.2 KiB
C

/*
* builtin-stat.c
*
* Builtin stat command: Give a precise performance counters summary
* overview about any workload, CPU or specific PID.
*
* Sample output:
$ perf stat ~/hackbench 10
Time: 0.104
Performance counter stats for '/home/mingo/hackbench':
1255.538611 task clock ticks # 10.143 CPU utilization factor
54011 context switches # 0.043 M/sec
385 CPU migrations # 0.000 M/sec
17755 pagefaults # 0.014 M/sec
3808323185 CPU cycles # 3033.219 M/sec
1575111190 instructions # 1254.530 M/sec
17367895 cache references # 13.833 M/sec
7674421 cache misses # 6.112 M/sec
Wall-clock time elapsed: 123.786620 msecs
*
* Copyright (C) 2008, Red Hat Inc, Ingo Molnar <mingo@redhat.com>
*
* Improvements and fixes by:
*
* Arjan van de Ven <arjan@linux.intel.com>
* Yanmin Zhang <yanmin.zhang@intel.com>
* Wu Fengguang <fengguang.wu@intel.com>
* Mike Galbraith <efault@gmx.de>
* Paul Mackerras <paulus@samba.org>
*
* Released under the GPL v2. (and only v2, not any later version)
*/
#include "perf.h"
#include "builtin.h"
#include "util/util.h"
#include "util/parse-options.h"
#include "util/parse-events.h"
#include <sys/prctl.h>
static int system_wide = 0;
static int inherit = 1;
static __u64 default_event_id[MAX_COUNTERS] = {
EID(PERF_TYPE_SOFTWARE, PERF_COUNT_TASK_CLOCK),
EID(PERF_TYPE_SOFTWARE, PERF_COUNT_CONTEXT_SWITCHES),
EID(PERF_TYPE_SOFTWARE, PERF_COUNT_CPU_MIGRATIONS),
EID(PERF_TYPE_SOFTWARE, PERF_COUNT_PAGE_FAULTS),
EID(PERF_TYPE_HARDWARE, PERF_COUNT_CPU_CYCLES),
EID(PERF_TYPE_HARDWARE, PERF_COUNT_INSTRUCTIONS),
EID(PERF_TYPE_HARDWARE, PERF_COUNT_CACHE_REFERENCES),
EID(PERF_TYPE_HARDWARE, PERF_COUNT_CACHE_MISSES),
};
static int default_interval = 100000;
static int event_count[MAX_COUNTERS];
static int fd[MAX_NR_CPUS][MAX_COUNTERS];
static int target_pid = -1;
static int nr_cpus = 0;
static unsigned int page_size;
static int scale = 1;
static const unsigned int default_count[] = {
1000000,
1000000,
10000,
10000,
1000000,
10000,
};
static __u64 event_res[MAX_COUNTERS][3];
static __u64 event_scaled[MAX_COUNTERS];
static __u64 runtime_nsecs;
static __u64 walltime_nsecs;
static void create_perfstat_counter(int counter)
{
struct perf_counter_attr attr;
memset(&attr, 0, sizeof(attr));
attr.config = event_id[counter];
attr.sample_type = 0;
attr.exclude_kernel = event_mask[counter] & EVENT_MASK_KERNEL;
attr.exclude_user = event_mask[counter] & EVENT_MASK_USER;
if (scale)
attr.read_format = PERF_FORMAT_TOTAL_TIME_ENABLED |
PERF_FORMAT_TOTAL_TIME_RUNNING;
if (system_wide) {
int cpu;
for (cpu = 0; cpu < nr_cpus; cpu ++) {
fd[cpu][counter] = sys_perf_counter_open(&attr, -1, cpu, -1, 0);
if (fd[cpu][counter] < 0) {
printf("perfstat error: syscall returned with %d (%s)\n",
fd[cpu][counter], strerror(errno));
exit(-1);
}
}
} else {
attr.inherit = inherit;
attr.disabled = 1;
fd[0][counter] = sys_perf_counter_open(&attr, 0, -1, -1, 0);
if (fd[0][counter] < 0) {
printf("perfstat error: syscall returned with %d (%s)\n",
fd[0][counter], strerror(errno));
exit(-1);
}
}
}
/*
* Does the counter have nsecs as a unit?
*/
static inline int nsec_counter(int counter)
{
if (event_id[counter] == EID(PERF_TYPE_SOFTWARE, PERF_COUNT_CPU_CLOCK))
return 1;
if (event_id[counter] == EID(PERF_TYPE_SOFTWARE, PERF_COUNT_TASK_CLOCK))
return 1;
return 0;
}
/*
* Read out the results of a single counter:
*/
static void read_counter(int counter)
{
__u64 *count, single_count[3];
ssize_t res;
int cpu, nv;
int scaled;
count = event_res[counter];
count[0] = count[1] = count[2] = 0;
nv = scale ? 3 : 1;
for (cpu = 0; cpu < nr_cpus; cpu ++) {
res = read(fd[cpu][counter], single_count, nv * sizeof(__u64));
assert(res == nv * sizeof(__u64));
count[0] += single_count[0];
if (scale) {
count[1] += single_count[1];
count[2] += single_count[2];
}
}
scaled = 0;
if (scale) {
if (count[2] == 0) {
event_scaled[counter] = -1;
count[0] = 0;
return;
}
if (count[2] < count[1]) {
event_scaled[counter] = 1;
count[0] = (unsigned long long)
((double)count[0] * count[1] / count[2] + 0.5);
}
}
/*
* Save the full runtime - to allow normalization during printout:
*/
if (event_id[counter] == EID(PERF_TYPE_SOFTWARE, PERF_COUNT_TASK_CLOCK))
runtime_nsecs = count[0];
}
/*
* Print out the results of a single counter:
*/
static void print_counter(int counter)
{
__u64 *count;
int scaled;
count = event_res[counter];
scaled = event_scaled[counter];
if (scaled == -1) {
fprintf(stderr, " %14s %-20s\n",
"<not counted>", event_name(counter));
return;
}
if (nsec_counter(counter)) {
double msecs = (double)count[0] / 1000000;
fprintf(stderr, " %14.6f %-20s",
msecs, event_name(counter));
if (event_id[counter] ==
EID(PERF_TYPE_SOFTWARE, PERF_COUNT_TASK_CLOCK)) {
fprintf(stderr, " # %11.3f CPU utilization factor",
(double)count[0] / (double)walltime_nsecs);
}
} else {
fprintf(stderr, " %14Ld %-20s",
count[0], event_name(counter));
if (runtime_nsecs)
fprintf(stderr, " # %11.3f M/sec",
(double)count[0]/runtime_nsecs*1000.0);
}
if (scaled)
fprintf(stderr, " (scaled from %.2f%%)",
(double) count[2] / count[1] * 100);
fprintf(stderr, "\n");
}
static int do_perfstat(int argc, const char **argv)
{
unsigned long long t0, t1;
int counter;
int status;
int pid;
int i;
if (!system_wide)
nr_cpus = 1;
for (counter = 0; counter < nr_counters; counter++)
create_perfstat_counter(counter);
/*
* Enable counters and exec the command:
*/
t0 = rdclock();
prctl(PR_TASK_PERF_COUNTERS_ENABLE);
if ((pid = fork()) < 0)
perror("failed to fork");
if (!pid) {
if (execvp(argv[0], (char **)argv)) {
perror(argv[0]);
exit(-1);
}
}
while (wait(&status) >= 0)
;
prctl(PR_TASK_PERF_COUNTERS_DISABLE);
t1 = rdclock();
walltime_nsecs = t1 - t0;
fflush(stdout);
fprintf(stderr, "\n");
fprintf(stderr, " Performance counter stats for \'%s", argv[0]);
for (i = 1; i < argc; i++)
fprintf(stderr, " %s", argv[i]);
fprintf(stderr, "\':\n");
fprintf(stderr, "\n");
for (counter = 0; counter < nr_counters; counter++)
read_counter(counter);
for (counter = 0; counter < nr_counters; counter++)
print_counter(counter);
fprintf(stderr, "\n");
fprintf(stderr, " Wall-clock time elapsed: %12.6f msecs\n",
(double)(t1-t0)/1e6);
fprintf(stderr, "\n");
return 0;
}
static void skip_signal(int signo)
{
}
static const char * const stat_usage[] = {
"perf stat [<options>] <command>",
NULL
};
static char events_help_msg[EVENTS_HELP_MAX];
static const struct option options[] = {
OPT_CALLBACK('e', "event", NULL, "event",
events_help_msg, parse_events),
OPT_INTEGER('c', "count", &default_interval,
"event period to sample"),
OPT_BOOLEAN('i', "inherit", &inherit,
"child tasks inherit counters"),
OPT_INTEGER('p', "pid", &target_pid,
"stat events on existing pid"),
OPT_BOOLEAN('a', "all-cpus", &system_wide,
"system-wide collection from all CPUs"),
OPT_BOOLEAN('l', "scale", &scale,
"scale/normalize counters"),
OPT_END()
};
int cmd_stat(int argc, const char **argv, const char *prefix)
{
int counter;
page_size = sysconf(_SC_PAGE_SIZE);
create_events_help(events_help_msg);
memcpy(event_id, default_event_id, sizeof(default_event_id));
argc = parse_options(argc, argv, options, stat_usage, 0);
if (!argc)
usage_with_options(stat_usage, options);
if (!nr_counters) {
nr_counters = 8;
}
for (counter = 0; counter < nr_counters; counter++) {
if (event_count[counter])
continue;
event_count[counter] = default_interval;
}
nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
assert(nr_cpus <= MAX_NR_CPUS);
assert(nr_cpus >= 0);
/*
* We dont want to block the signals - that would cause
* child tasks to inherit that and Ctrl-C would not work.
* What we want is for Ctrl-C to work in the exec()-ed
* task, but being ignored by perf stat itself:
*/
signal(SIGINT, skip_signal);
signal(SIGALRM, skip_signal);
signal(SIGABRT, skip_signal);
return do_perfstat(argc, argv);
}