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|
/*
* 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>
* Jaswinder Singh Rajput <jaswinder@kernel.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>
#include <math.h>
static struct perf_counter_attr default_attrs[] = {
{ .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_TASK_CLOCK },
{ .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_CONTEXT_SWITCHES},
{ .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_CPU_MIGRATIONS },
{ .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_PAGE_FAULTS },
{ .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_CPU_CYCLES },
{ .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_INSTRUCTIONS },
{ .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_CACHE_REFERENCES},
{ .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_CACHE_MISSES },
};
#define MAX_RUN 100
static int system_wide = 0;
static int verbose = 0;
static unsigned int nr_cpus = 0;
static int run_idx = 0;
static int run_count = 1;
static int inherit = 1;
static int scale = 1;
static int target_pid = -1;
static int null_run = 0;
static int fd[MAX_NR_CPUS][MAX_COUNTERS];
static u64 runtime_nsecs[MAX_RUN];
static u64 walltime_nsecs[MAX_RUN];
static u64 runtime_cycles[MAX_RUN];
static u64 event_res[MAX_RUN][MAX_COUNTERS][3];
static u64 event_scaled[MAX_RUN][MAX_COUNTERS];
static u64 event_res_avg[MAX_COUNTERS][3];
static u64 event_res_noise[MAX_COUNTERS][3];
static u64 event_scaled_avg[MAX_COUNTERS];
static u64 runtime_nsecs_avg;
static u64 runtime_nsecs_noise;
static u64 walltime_nsecs_avg;
static u64 walltime_nsecs_noise;
static u64 runtime_cycles_avg;
static u64 runtime_cycles_noise;
#define MATCH_EVENT(t, c, counter) \
(attrs[counter].type == PERF_TYPE_##t && \
attrs[counter].config == PERF_COUNT_##c)
#define ERR_PERF_OPEN \
"Error: counter %d, sys_perf_counter_open() syscall returned with %d (%s)\n"
static void create_perf_stat_counter(int counter, int pid)
{
struct perf_counter_attr *attr = attrs + counter;
if (scale)
attr->read_format = PERF_FORMAT_TOTAL_TIME_ENABLED |
PERF_FORMAT_TOTAL_TIME_RUNNING;
if (system_wide) {
unsigned 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 && verbose)
fprintf(stderr, ERR_PERF_OPEN, counter,
fd[cpu][counter], strerror(errno));
}
} else {
attr->inherit = inherit;
attr->disabled = 1;
attr->enable_on_exec = 1;
fd[0][counter] = sys_perf_counter_open(attr, pid, -1, -1, 0);
if (fd[0][counter] < 0 && verbose)
fprintf(stderr, ERR_PERF_OPEN, counter,
fd[0][counter], strerror(errno));
}
}
/*
* Does the counter have nsecs as a unit?
*/
static inline int nsec_counter(int counter)
{
if (MATCH_EVENT(SOFTWARE, SW_CPU_CLOCK, counter) ||
MATCH_EVENT(SOFTWARE, SW_TASK_CLOCK, counter))
return 1;
return 0;
}
/*
* Read out the results of a single counter:
*/
static void read_counter(int counter)
{
u64 *count, single_count[3];
unsigned int cpu;
size_t res, nv;
int scaled;
count = event_res[run_idx][counter];
count[0] = count[1] = count[2] = 0;
nv = scale ? 3 : 1;
for (cpu = 0; cpu < nr_cpus; cpu++) {
if (fd[cpu][counter] < 0)
continue;
res = read(fd[cpu][counter], single_count, nv * sizeof(u64));
assert(res == nv * sizeof(u64));
close(fd[cpu][counter]);
fd[cpu][counter] = -1;
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[run_idx][counter] = -1;
count[0] = 0;
return;
}
if (count[2] < count[1]) {
event_scaled[run_idx][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 (MATCH_EVENT(SOFTWARE, SW_TASK_CLOCK, counter))
runtime_nsecs[run_idx] = count[0];
if (MATCH_EVENT(HARDWARE, HW_CPU_CYCLES, counter))
runtime_cycles[run_idx] = count[0];
}
static int run_perf_stat(int argc __used, const char **argv)
{
unsigned long long t0, t1;
int status = 0;
int counter;
int pid;
int child_ready_pipe[2], go_pipe[2];
char buf;
if (!system_wide)
nr_cpus = 1;
if (pipe(child_ready_pipe) < 0 || pipe(go_pipe) < 0) {
perror("failed to create pipes");
exit(1);
}
if ((pid = fork()) < 0)
perror("failed to fork");
if (!pid) {
close(child_ready_pipe[0]);
close(go_pipe[1]);
fcntl(go_pipe[0], F_SETFD, FD_CLOEXEC);
/*
* Do a dummy execvp to get the PLT entry resolved,
* so we avoid the resolver overhead on the real
* execvp call.
*/
execvp("", (char **)argv);
/*
|