* 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 "util/util.h"
#include "util/parse-options.h"
#include "util/parse-events.h"
+#include "util/event.h"
+#include "util/debug.h"
#include <sys/prctl.h>
+#include <math.h>
-static struct perf_counter_attr default_attrs[MAX_COUNTERS] = {
+static struct perf_counter_attr default_attrs[] = {
- { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_TASK_CLOCK },
- { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_CONTEXT_SWITCHES },
- { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_CPU_MIGRATIONS },
- { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_PAGE_FAULTS },
+ { .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 },
- { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_CPU_CYCLES },
- { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_INSTRUCTIONS },
- { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_CACHE_REFERENCES },
- { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_CACHE_MISSES },
};
static int system_wide = 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 int target_pid = -1;
-static int nr_cpus = 0;
-static unsigned int page_size;
+static int event_scaled[MAX_COUNTERS];
-static int scale = 1;
-
-static const unsigned int default_count[] = {
- 1000000,
- 1000000,
- 10000,
- 10000,
- 1000000,
- 10000,
+struct stats
+{
+ double n, mean, M2;
};
-static __u64 event_res[MAX_COUNTERS][3];
-static __u64 event_scaled[MAX_COUNTERS];
+static void update_stats(struct stats *stats, u64 val)
+{
+ double delta;
+
+ stats->n++;
+ delta = val - stats->mean;
+ stats->mean += delta / stats->n;
+ stats->M2 += delta*(val - stats->mean);
+}
+
+static double avg_stats(struct stats *stats)
+{
+ return stats->mean;
+}
+
+/*
+ * http://en.wikipedia.org/wiki/Algorithms_for_calculating_variance
+ *
+ * (\Sum n_i^2) - ((\Sum n_i)^2)/n
+ * s^2 = -------------------------------
+ * n - 1
+ *
+ * http://en.wikipedia.org/wiki/Stddev
+ *
+ * The std dev of the mean is related to the std dev by:
+ *
+ * s
+ * s_mean = -------
+ * sqrt(n)
+ *
+ */
+static double stddev_stats(struct stats *stats)
+{
+ double variance = stats->M2 / (stats->n - 1);
+ double variance_mean = variance / stats->n;
+
+ return sqrt(variance_mean);
+}
+
+struct stats event_res_stats[MAX_COUNTERS][3];
+struct stats runtime_nsecs_stats;
+struct stats walltime_nsecs_stats;
+struct stats runtime_cycles_stats;
+
+#define MATCH_EVENT(t, c, counter) \
+ (attrs[counter].type == PERF_TYPE_##t && \
+ attrs[counter].config == PERF_COUNT_##c)
-static __u64 runtime_nsecs;
-static __u64 walltime_nsecs;
+#define ERR_PERF_OPEN \
+"Error: counter %d, sys_perf_counter_open() syscall returned with %d (%s)\n"
-static void create_perfstat_counter(int counter)
+static void create_perf_stat_counter(int counter, int pid)
{
struct perf_counter_attr *attr = attrs + counter;
PERF_FORMAT_TOTAL_TIME_RUNNING;
if (system_wide) {
- int cpu;
- for (cpu = 0; cpu < nr_cpus; cpu ++) {
+ 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) {
- printf("perfstat error: syscall returned with %d (%s)\n",
- fd[cpu][counter], strerror(errno));
- exit(-1);
- }
+ if (fd[cpu][counter] < 0 && verbose)
+ fprintf(stderr, ERR_PERF_OPEN, counter,
+ fd[cpu][counter], strerror(errno));
}
} 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);
- }
+ 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));
}
}
*/
static inline int nsec_counter(int counter)
{
- if (attrs[counter].type != PERF_TYPE_SOFTWARE)
- return 0;
-
- if (attrs[counter].config == PERF_COUNT_CPU_CLOCK)
- return 1;
-
- if (attrs[counter].config == PERF_COUNT_TASK_CLOCK)
+ if (MATCH_EVENT(SOFTWARE, SW_CPU_CLOCK, counter) ||
+ MATCH_EVENT(SOFTWARE, SW_TASK_CLOCK, counter))
return 1;
return 0;
*/
static void read_counter(int counter)
{
- __u64 *count, single_count[3];
- ssize_t res;
- int cpu, nv;
+ u64 count[3], single_count[3];
+ unsigned int cpu;
+ size_t res, nv;
int scaled;
-
- count = event_res[counter];
+ int i;
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));
+ 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) {
((double)count[0] * count[1] / count[2] + 0.5);
}
}
- /*
- * Save the full runtime - to allow normalization during printout:
- */
- if (attrs[counter].type == PERF_TYPE_SOFTWARE &&
- attrs[counter].config == 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];
+ for (i = 0; i < 3; i++)
+ update_stats(&event_res_stats[counter][i], count[i]);
- if (scaled == -1) {
- fprintf(stderr, " %14s %-20s\n",
- "<not counted>", event_name(counter));
- return;
+ if (verbose) {
+ fprintf(stderr, "%s: %Ld %Ld %Ld\n", event_name(counter),
+ count[0], count[1], count[2]);
}
- if (nsec_counter(counter)) {
- double msecs = (double)count[0] / 1000000;
-
- fprintf(stderr, " %14.6f %-20s",
- msecs, event_name(counter));
- if (attrs[counter].type == PERF_TYPE_SOFTWARE &&
- attrs[counter].config == 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");
+ /*
+ * Save the full runtime - to allow normalization during printout:
+ */
+ if (MATCH_EVENT(SOFTWARE, SW_TASK_CLOCK, counter))
+ update_stats(&runtime_nsecs_stats, count[0]);
+ if (MATCH_EVENT(HARDWARE, HW_CPU_CYCLES, counter))
+ update_stats(&runtime_cycles_stats, count[0]);
}
-static int do_perfstat(int argc, const char **argv)
+static int run_perf_stat(int argc __used, const char **argv)
{
unsigned long long t0, t1;
+ int status = 0;
int counter;
- int status;
int pid;
- int i;
+ 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);
+
+ /*
+ * Tell the parent we're ready to go
+ */
+ close(child_ready_pipe[1]);
+
+ /*
+ * Wait until the parent tells us to go.
+ */
+ if (read(go_pipe[0], &buf, 1) == -1)
+ perror("unable to read pipe");
+
+ execvp(argv[0], (char **)argv);
+
+ perror(argv[0]);
+ exit(-1);
+ }
+
+ /*
+ * Wait for the child to be ready to exec.
+ */
+ close(child_ready_pipe[1]);
+ close(go_pipe[0]);
+ if (read(child_ready_pipe[0], &buf, 1) == -1)
+ perror("unable to read pipe");
+ close(child_ready_pipe[0]);
+
for (counter = 0; counter < nr_counters; counter++)
- create_perfstat_counter(counter);
+ create_perf_stat_counter(counter, pid);
/*
* Enable counters and exec the command:
*/
t0 = rdclock();
- prctl(PR_TASK_PERF_COUNTERS_ENABLE);
- if ((pid = fork()) < 0)
- perror("failed to fork");
+ close(go_pipe[1]);
+ wait(&status);
- if (!pid) {
- if (execvp(argv[0], (char **)argv)) {
- perror(argv[0]);
- exit(-1);
- }
+ t1 = rdclock();
+
+ update_stats(&walltime_nsecs_stats, t1 - t0);
+
+ for (counter = 0; counter < nr_counters; counter++)
+ read_counter(counter);
+
+ return WEXITSTATUS(status);
+}
+
+static void print_noise(int counter, double avg)
+{
+ if (run_count == 1)
+ return;
+
+ fprintf(stderr, " ( +- %7.3f%% )",
+ 100 * stddev_stats(&event_res_stats[counter][0]) / avg);
+}
+
+static void nsec_printout(int counter, double avg)
+{
+ double msecs = avg / 1e6;
+
+ fprintf(stderr, " %14.6f %-24s", msecs, event_name(counter));
+
+ if (MATCH_EVENT(SOFTWARE, SW_TASK_CLOCK, counter)) {
+ fprintf(stderr, " # %10.3f CPUs ",
+ avg / avg_stats(&walltime_nsecs_stats));
}
+}
- while (wait(&status) >= 0)
- ;
+static void abs_printout(int counter, double avg)
+{
+ fprintf(stderr, " %14.0f %-24s", avg, event_name(counter));
- prctl(PR_TASK_PERF_COUNTERS_DISABLE);
- t1 = rdclock();
+ if (MATCH_EVENT(HARDWARE, HW_INSTRUCTIONS, counter)) {
+ fprintf(stderr, " # %10.3f IPC ",
+ avg / avg_stats(&runtime_cycles_stats));
+ } else {
+ fprintf(stderr, " # %10.3f M/sec",
+ 1000.0 * avg / avg_stats(&runtime_nsecs_stats));
+ }
+}
- walltime_nsecs = t1 - t0;
+/*
+ * Print out the results of a single counter:
+ */
+static void print_counter(int counter)
+{
+ double avg = avg_stats(&event_res_stats[counter][0]);
+ int scaled = event_scaled[counter];
+
+ if (scaled == -1) {
+ fprintf(stderr, " %14s %-24s\n",
+ "<not counted>", event_name(counter));
+ return;
+ }
+
+ if (nsec_counter(counter))
+ nsec_printout(counter, avg);
+ else
+ abs_printout(counter, avg);
+
+ print_noise(counter, avg);
+
+ if (scaled) {
+ double avg_enabled, avg_running;
+
+ avg_enabled = avg_stats(&event_res_stats[counter][1]);
+ avg_running = avg_stats(&event_res_stats[counter][2]);
+
+ fprintf(stderr, " (scaled from %.2f%%)",
+ 100 * avg_running / avg_enabled);
+ }
+
+ fprintf(stderr, "\n");
+}
+
+static void print_stat(int argc, const char **argv)
+{
+ int i, counter;
fflush(stdout);
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);
+ fprintf(stderr, "\'");
+ if (run_count > 1)
+ fprintf(stderr, " (%d runs)", run_count);
+ fprintf(stderr, ":\n\n");
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;
+ fprintf(stderr, " %14.9f seconds time elapsed",
+ avg_stats(&walltime_nsecs_stats)/1e9);
+ if (run_count > 1) {
+ fprintf(stderr, " ( +- %7.3f%% )",
+ 100*stddev_stats(&walltime_nsecs_stats) /
+ avg_stats(&walltime_nsecs_stats));
+ }
+ fprintf(stderr, "\n\n");
}
+static volatile int signr = -1;
+
static void skip_signal(int signo)
{
+ signr = signo;
+}
+
+static void sig_atexit(void)
+{
+ if (signr == -1)
+ return;
+
+ signal(signr, SIG_DFL);
+ kill(getpid(), signr);
}
static const char * const stat_usage[] = {
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('S', "scale", &scale,
- "scale/normalize counters"),
+ "system-wide collection from all CPUs"),
+ OPT_BOOLEAN('c', "scale", &scale,
+ "scale/normalize counters"),
+ OPT_BOOLEAN('v', "verbose", &verbose,
+ "be more verbose (show counter open errors, etc)"),
+ OPT_INTEGER('r', "repeat", &run_count,
+ "repeat command and print average + stddev (max: 100)"),
+ OPT_BOOLEAN('n', "null", &null_run,
+ "null run - dont start any counters"),
OPT_END()
};
-int cmd_stat(int argc, const char **argv, const char *prefix)
+int cmd_stat(int argc, const char **argv, const char *prefix __used)
{
- page_size = sysconf(_SC_PAGE_SIZE);
-
- memcpy(attrs, default_attrs, sizeof(attrs));
+ int status;
- argc = parse_options(argc, argv, options, stat_usage, 0);
+ argc = parse_options(argc, argv, options, stat_usage,
+ PARSE_OPT_STOP_AT_NON_OPTION);
if (!argc)
usage_with_options(stat_usage, options);
+ if (run_count <= 0)
+ usage_with_options(stat_usage, options);
- if (!nr_counters)
- nr_counters = 8;
+ /* Set attrs and nr_counters if no event is selected and !null_run */
+ if (!null_run && !nr_counters) {
+ memcpy(attrs, default_attrs, sizeof(default_attrs));
+ nr_counters = ARRAY_SIZE(default_attrs);
+ }
nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
assert(nr_cpus <= MAX_NR_CPUS);
- assert(nr_cpus >= 0);
+ assert((int)nr_cpus >= 0);
/*
* We dont want to block the signals - that would cause
* What we want is for Ctrl-C to work in the exec()-ed
* task, but being ignored by perf stat itself:
*/
+ atexit(sig_atexit);
signal(SIGINT, skip_signal);
signal(SIGALRM, skip_signal);
signal(SIGABRT, skip_signal);
- return do_perfstat(argc, argv);
+ status = 0;
+ for (run_idx = 0; run_idx < run_count; run_idx++) {
+ if (run_count != 1 && verbose)
+ fprintf(stderr, "[ perf stat: executing run #%d ... ]\n", run_idx + 1);
+ status = run_perf_stat(argc, argv);
+ }
+
+ print_stat(argc, argv);
+
+ return status;
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff