* 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 <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_SW_TASK_CLOCK },
{ .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_CONTEXT_SWITCHES},
static int system_wide = 0;
static int verbose = 0;
-static int nr_cpus = 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_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)
+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;
+ 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)
fd[cpu][counter], strerror(errno));
}
} else {
- attr->inherit = inherit;
- attr->disabled = 1;
+ attr->inherit = inherit;
+ attr->disabled = 1;
+ attr->enable_on_exec = 1;
- fd[0][counter] = sys_perf_counter_open(attr, 0, -1, -1, 0);
+ 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_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;
+ unsigned int cpu;
+ size_t res, nv;
int scaled;
count = event_res[run_idx][counter];
res = read(fd[cpu][counter], single_count, nv * sizeof(u64));
assert(res == nv * sizeof(u64));
+
close(fd[cpu][counter]);
fd[cpu][counter] = -1;
/*
* Save the full runtime - to allow normalization during printout:
*/
- if (attrs[counter].type == PERF_TYPE_SOFTWARE &&
- attrs[counter].config == PERF_COUNT_SW_TASK_CLOCK)
+ if (MATCH_EVENT(SOFTWARE, SW_TASK_CLOCK, counter))
runtime_nsecs[run_idx] = count[0];
- if (attrs[counter].type == PERF_TYPE_HARDWARE &&
- attrs[counter].config == PERF_COUNT_HW_CPU_CYCLES)
+ if (MATCH_EVENT(HARDWARE, HW_CPU_CYCLES, counter))
runtime_cycles[run_idx] = 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);
}
+ /*
+ * 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;
{
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_SW_TASK_CLOCK) {
+ fprintf(stderr, " %14.6f %-24s", msecs, event_name(counter));
+ if (MATCH_EVENT(SOFTWARE, SW_TASK_CLOCK, counter)) {
if (walltime_nsecs_avg)
fprintf(stderr, " # %10.3f CPUs ",
(double)count[0] / (double)walltime_nsecs_avg);
static void abs_printout(int counter, u64 *count, u64 *noise)
{
- fprintf(stderr, " %14Ld %-20s", count[0], event_name(counter));
+ fprintf(stderr, " %14Ld %-24s", count[0], event_name(counter));
if (runtime_cycles_avg &&
- attrs[counter].type == PERF_TYPE_HARDWARE &&
- attrs[counter].config == PERF_COUNT_HW_INSTRUCTIONS) {
-
+ MATCH_EVENT(HARDWARE, HW_INSTRUCTIONS, counter)) {
fprintf(stderr, " # %10.3f IPC ",
(double)count[0] / (double)runtime_cycles_avg);
} else {
scaled = event_scaled_avg[counter];
if (scaled == -1) {
- fprintf(stderr, " %14s %-20s\n",
+ fprintf(stderr, " %14s %-24s\n",
"<not counted>", event_name(counter));
return;
}
event_res_avg[j]+1, event_res[i][j]+1);
update_avg("counter/2", j,
event_res_avg[j]+2, event_res[i][j]+2);
- update_avg("scaled", j,
- event_scaled_avg + j, event_scaled[i]+j);
+ if (event_scaled[i][j] != (u64)-1)
+ update_avg("scaled", j,
+ event_scaled_avg + j, event_scaled[i]+j);
+ else
+ event_scaled_avg[j] = -1;
}
}
runtime_nsecs_avg /= run_count;
for (counter = 0; counter < nr_counters; counter++)
print_counter(counter);
-
fprintf(stderr, "\n");
- fprintf(stderr, " %14.9f seconds time elapsed.\n",
+ fprintf(stderr, " %14.9f seconds time elapsed",
(double)walltime_nsecs_avg/1e9);
- fprintf(stderr, "\n");
+ if (run_count > 1) {
+ fprintf(stderr, " ( +- %7.3f%% )",
+ 100.0*(double)walltime_nsecs_noise/(double)walltime_nsecs_avg);
+ }
+ fprintf(stderr, "\n\n");
}
static volatile int signr = -1;
"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;
- 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)
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
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff