* 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_event_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_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_HW_CPU_CYCLES },
+ { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_INSTRUCTIONS },
+ { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_BRANCH_INSTRUCTIONS },
+ { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_BRANCH_MISSES },
+ { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_CACHE_REFERENCES },
+ { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_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 verbose = 0;
+static int scale = 1;
+static pid_t target_pid = -1;
+static pid_t child_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 scale = 1;
+static int event_scaled[MAX_COUNTERS];
-static const unsigned int default_count[] = {
- 1000000,
- 1000000,
- 10000,
- 10000,
- 1000000,
- 10000,
+struct stats
+{
+ double n, mean, M2;
};
-#define MAX_RUN 100
-
-static int run_count = 1;
-static int run_idx = 0;
-
-static __u64 event_res[MAX_RUN][MAX_COUNTERS][3];
-static __u64 event_scaled[MAX_RUN][MAX_COUNTERS];
-
-//static __u64 event_hist[MAX_RUN][MAX_COUNTERS][3];
+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 __u64 runtime_nsecs[MAX_RUN];
-static __u64 walltime_nsecs[MAX_RUN];
-static __u64 runtime_cycles[MAX_RUN];
+static double avg_stats(struct stats *stats)
+{
+ return stats->mean;
+}
-static __u64 event_res_avg[MAX_COUNTERS][3];
-static __u64 event_res_noise[MAX_COUNTERS][3];
+/*
+ * 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;
-static __u64 event_scaled_avg[MAX_COUNTERS];
+ return sqrt(variance_mean);
+}
-static __u64 runtime_nsecs_avg;
-static __u64 runtime_nsecs_noise;
+struct stats event_res_stats[MAX_COUNTERS][3];
+struct stats runtime_nsecs_stats;
+struct stats walltime_nsecs_stats;
+struct stats runtime_cycles_stats;
+struct stats runtime_branches_stats;
-static __u64 walltime_nsecs_avg;
-static __u64 walltime_nsecs_noise;
+#define MATCH_EVENT(t, c, counter) \
+ (attrs[counter].type == PERF_TYPE_##t && \
+ attrs[counter].config == PERF_COUNT_##c)
-static __u64 runtime_cycles_avg;
-static __u64 runtime_cycles_noise;
+#define ERR_PERF_OPEN \
+"Error: counter %d, sys_perf_event_open() syscall returned with %d (%s)\n"
-static void create_perf_stat_counter(int counter)
+static void create_perf_stat_counter(int counter, int pid)
{
- struct perf_counter_attr *attr = attrs + counter;
+ struct perf_event_attr *attr = attrs + counter;
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 && verbose) {
- printf("Error: counter %d, sys_perf_counter_open() syscall returned with %d (%s)\n", counter, fd[cpu][counter], strerror(errno));
- }
- }
- } else {
- attr->inherit = inherit;
- attr->disabled = 1;
+ unsigned int cpu;
- fd[0][counter] = sys_perf_counter_open(attr, 0, -1, -1, 0);
- if (fd[0][counter] < 0 && verbose) {
- printf("Error: counter %d, sys_perf_counter_open() syscall returned with %d (%s)\n", counter, fd[0][counter], strerror(errno));
+ for (cpu = 0; cpu < nr_cpus; cpu++) {
+ fd[cpu][counter] = sys_perf_event_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_event_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_SW_CPU_CLOCK)
- return 1;
-
- if (attrs[counter].config == PERF_COUNT_SW_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[run_idx][counter];
+ int i;
count[0] = count[1] = count[2] = 0;
nv = scale ? 3 : 1;
- for (cpu = 0; cpu < nr_cpus; cpu ++) {
+ 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));
+ res = read(fd[cpu][counter], single_count, nv * sizeof(u64));
+ assert(res == nv * sizeof(u64));
+
close(fd[cpu][counter]);
fd[cpu][counter] = -1;
scaled = 0;
if (scale) {
if (count[2] == 0) {
- event_scaled[run_idx][counter] = -1;
+ event_scaled[counter] = -1;
count[0] = 0;
return;
}
if (count[2] < count[1]) {
- event_scaled[run_idx][counter] = 1;
+ event_scaled[counter] = 1;
count[0] = (unsigned long long)
((double)count[0] * count[1] / count[2] + 0.5);
}
}
+
+ for (i = 0; i < 3; i++)
+ update_stats(&event_res_stats[counter][i], count[i]);
+
+ if (verbose) {
+ fprintf(stderr, "%s: %Ld %Ld %Ld\n", event_name(counter),
+ count[0], count[1], count[2]);
+ }
+
/*
* Save the full runtime - to allow normalization during printout:
*/
- if (attrs[counter].type == PERF_TYPE_SOFTWARE &&
- attrs[counter].config == PERF_COUNT_SW_TASK_CLOCK)
- runtime_nsecs[run_idx] = count[0];
- if (attrs[counter].type == PERF_TYPE_HARDWARE &&
- attrs[counter].config == PERF_COUNT_HW_CPU_CYCLES)
- runtime_cycles[run_idx] = count[0];
+ 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]);
+ if (MATCH_EVENT(HARDWARE, HW_BRANCH_INSTRUCTIONS, counter))
+ update_stats(&runtime_branches_stats, count[0]);
}
-static int run_perf_stat(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 pid;
+ int child_ready_pipe[2], go_pipe[2];
+ char buf;
if (!system_wide)
nr_cpus = 1;
- for (counter = 0; counter < nr_counters; counter++)
- create_perf_stat_counter(counter);
-
- /*
- * Enable counters and exec the command:
- */
- t0 = rdclock();
- prctl(PR_TASK_PERF_COUNTERS_ENABLE);
+ 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) {
- if (execvp(argv[0], (char **)argv)) {
- perror(argv[0]);
- exit(-1);
- }
+ 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);
}
+ child_pid = pid;
+
+ /*
+ * 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_perf_stat_counter(counter, pid);
+
+ /*
+ * Enable counters and exec the command:
+ */
+ t0 = rdclock();
+
+ close(go_pipe[1]);
wait(&status);
- prctl(PR_TASK_PERF_COUNTERS_DISABLE);
t1 = rdclock();
- walltime_nsecs[run_idx] = t1 - t0;
+ update_stats(&walltime_nsecs_stats, t1 - t0);
for (counter = 0; counter < nr_counters; counter++)
read_counter(counter);
return WEXITSTATUS(status);
}
-static void print_noise(__u64 *count, __u64 *noise)
+static void print_noise(int counter, double avg)
{
- if (run_count > 1)
- fprintf(stderr, " ( +- %7.3f%% )",
- (double)noise[0]/(count[0]+1)*100.0);
+ if (run_count == 1)
+ return;
+
+ fprintf(stderr, " ( +- %7.3f%% )",
+ 100 * stddev_stats(&event_res_stats[counter][0]) / avg);
}
-static void nsec_printout(int counter, __u64 *count, __u64 *noise)
+static void nsec_printout(int counter, double avg)
{
- double msecs = (double)count[0] / 1000000;
-
- fprintf(stderr, " %14.6f %-20s", msecs, event_name(counter));
+ double msecs = avg / 1e6;
- if (attrs[counter].type == PERF_TYPE_SOFTWARE &&
- attrs[counter].config == PERF_COUNT_SW_TASK_CLOCK) {
+ fprintf(stderr, " %14.6f %-24s", msecs, event_name(counter));
- if (walltime_nsecs_avg)
- fprintf(stderr, " # %10.3f CPUs ",
- (double)count[0] / (double)walltime_nsecs_avg);
+ if (MATCH_EVENT(SOFTWARE, SW_TASK_CLOCK, counter)) {
+ fprintf(stderr, " # %10.3f CPUs ",
+ avg / avg_stats(&walltime_nsecs_stats));
}
- print_noise(count, noise);
}
-static void abs_printout(int counter, __u64 *count, __u64 *noise)
+static void abs_printout(int counter, double avg)
{
- fprintf(stderr, " %14Ld %-20s", count[0], event_name(counter));
+ double total, ratio = 0.0;
- if (runtime_cycles_avg &&
- attrs[counter].type == PERF_TYPE_HARDWARE &&
- attrs[counter].config == PERF_COUNT_HW_INSTRUCTIONS) {
+ fprintf(stderr, " %14.0f %-24s", avg, event_name(counter));
- fprintf(stderr, " # %10.3f IPC ",
- (double)count[0] / (double)runtime_cycles_avg);
- } else {
- if (runtime_nsecs_avg) {
- fprintf(stderr, " # %10.3f M/sec",
- (double)count[0]/runtime_nsecs_avg*1000.0);
- }
+ if (MATCH_EVENT(HARDWARE, HW_INSTRUCTIONS, counter)) {
+ total = avg_stats(&runtime_cycles_stats);
+
+ if (total)
+ ratio = avg / total;
+
+ fprintf(stderr, " # %10.3f IPC ", ratio);
+ } else if (MATCH_EVENT(HARDWARE, HW_BRANCH_MISSES, counter) &&
+ runtime_branches_stats.n != 0) {
+ total = avg_stats(&runtime_branches_stats);
+
+ if (total)
+ ratio = avg * 100 / total;
+
+ fprintf(stderr, " # %10.3f %% ", ratio);
+
+ } else if (runtime_nsecs_stats.n != 0) {
+ total = avg_stats(&runtime_nsecs_stats);
+
+ if (total)
+ ratio = 1000.0 * avg / total;
+
+ fprintf(stderr, " # %10.3f M/sec", ratio);
}
- print_noise(count, noise);
}
/*
*/
static void print_counter(int counter)
{
- __u64 *count, *noise;
- int scaled;
-
- count = event_res_avg[counter];
- noise = event_res_noise[counter];
- scaled = event_scaled_avg[counter];
+ double avg = avg_stats(&event_res_stats[counter][0]);
+ int scaled = event_scaled[counter];
if (scaled == -1) {
- fprintf(stderr, " %14s %-20s\n",
+ fprintf(stderr, " %14s %-24s\n",
"<not counted>", event_name(counter));
return;
}
if (nsec_counter(counter))
- nsec_printout(counter, count, noise);
+ nsec_printout(counter, avg);
else
- abs_printout(counter, count, noise);
-
- if (scaled)
- fprintf(stderr, " (scaled from %.2f%%)",
- (double) count[2] / count[1] * 100);
+ abs_printout(counter, avg);
- fprintf(stderr, "\n");
-}
+ print_noise(counter, avg);
-/*
- * Normalize noise values down to stddev:
- */
-static void normalize(__u64 *val)
-{
- double res;
+ if (scaled) {
+ double avg_enabled, avg_running;
- res = (double)*val / (run_count * sqrt((double)run_count));
+ avg_enabled = avg_stats(&event_res_stats[counter][1]);
+ avg_running = avg_stats(&event_res_stats[counter][2]);
- *val = (__u64)res;
-}
-
-/*
- * Calculate the averages and noises:
- */
-static void calc_avg(void)
-{
- int i, j;
-
- for (i = 0; i < run_count; i++) {
- runtime_nsecs_avg += runtime_nsecs[i];
- walltime_nsecs_avg += walltime_nsecs[i];
- runtime_cycles_avg += runtime_cycles[i];
-
- for (j = 0; j < nr_counters; j++) {
- event_res_avg[j][0] += event_res[i][j][0];
- event_res_avg[j][1] += event_res[i][j][1];
- event_res_avg[j][2] += event_res[i][j][2];
- event_scaled_avg[j] += event_scaled[i][j];
- }
- }
- runtime_nsecs_avg /= run_count;
- walltime_nsecs_avg /= run_count;
- runtime_cycles_avg /= run_count;
-
- for (j = 0; j < nr_counters; j++) {
- event_res_avg[j][0] /= run_count;
- event_res_avg[j][1] /= run_count;
- event_res_avg[j][2] /= run_count;
- }
-
- for (i = 0; i < run_count; i++) {
- runtime_nsecs_noise +=
- abs((__s64)(runtime_nsecs[i] - runtime_nsecs_avg));
- walltime_nsecs_noise +=
- abs((__s64)(walltime_nsecs[i] - walltime_nsecs_avg));
- runtime_cycles_noise +=
- abs((__s64)(runtime_cycles[i] - runtime_cycles_avg));
-
- for (j = 0; j < nr_counters; j++) {
- event_res_noise[j][0] +=
- abs((__s64)(event_res[i][j][0] - event_res_avg[j][0]));
- event_res_noise[j][1] +=
- abs((__s64)(event_res[i][j][1] - event_res_avg[j][1]));
- event_res_noise[j][2] +=
- abs((__s64)(event_res[i][j][2] - event_res_avg[j][2]));
- }
+ fprintf(stderr, " (scaled from %.2f%%)",
+ 100 * avg_running / avg_enabled);
}
- normalize(&runtime_nsecs_noise);
- normalize(&walltime_nsecs_noise);
- normalize(&runtime_cycles_noise);
-
- for (j = 0; j < nr_counters; j++) {
- normalize(&event_res_noise[j][0]);
- normalize(&event_res_noise[j][1]);
- normalize(&event_res_noise[j][2]);
- }
+ fprintf(stderr, "\n");
}
static void print_stat(int argc, const char **argv)
{
int i, counter;
- calc_avg();
-
- run_idx = 0;
-
fflush(stdout);
fprintf(stderr, "\n");
for (counter = 0; counter < nr_counters; counter++)
print_counter(counter);
-
- fprintf(stderr, "\n");
- fprintf(stderr, " %14.9f seconds time elapsed.\n",
- (double)walltime_nsecs_avg/1e9);
fprintf(stderr, "\n");
+ 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 sig_atexit(void)
{
+ if (child_pid != -1)
+ kill(child_pid, SIGTERM);
+
if (signr == -1)
return;
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)
{
int status;
- page_size = sysconf(_SC_PAGE_SIZE);
-
- memcpy(attrs, default_attrs, sizeof(attrs));
-
- 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 || run_count > MAX_RUN)
+ 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
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);
+ fprintf(stderr, "[ perf stat: executing run #%d ... ]\n", run_idx + 1);
status = run_perf_stat(argc, argv);
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff