perf stat: Add no-aggregation mode to -a

This patch adds a new -A option to perf stat. If specified then perf stat does
not aggregate counts across all monitored CPUs in system-wide mode, i.e., when
using -a. This option is not supported in per-thread mode.

Being able to get a per-cpu breakdown is useful to detect imbalances between
CPUs when running a uniform workload than spans all monitored CPUs.

The second version corrects the missing cpumap[] support, so that it works when
the -C option is used.

The third version fixes a missing cpumap[] in print_counter() and removes a
stray patch in builtin-trace.c.

Examples on a 4-way system:

# perf stat -a   -e cycles,instructions -- sleep 1
 Performance counter stats for 'sleep 1':
         9592808135  cycles
         3490380006  instructions             #      0.364 IPC
        1.001584632  seconds time elapsed

# perf stat -a -A -e cycles,instructions -- sleep 1
 Performance counter stats for 'sleep 1':
CPU0            2398163767  cycles
CPU1            2398180817  cycles
CPU2            2398217115  cycles
CPU3            2398247483  cycles
CPU0             872282046  instructions             #      0.364 IPC
CPU1             873481776  instructions             #      0.364 IPC
CPU2             872638127  instructions             #      0.364 IPC
CPU3             872437789  instructions             #      0.364 IPC
        1.001556052  seconds time elapsed

Cc: David S. Miller <davem@davemloft.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Richter <robert.richter@amd.com>
LKML-Reference: <4ce257b5.1e07e30a.7b6b.3aa9@mx.google.com>
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Stephane Eranian 2010-11-16 11:05:01 +02:00 committed by Arnaldo Carvalho de Melo
parent ae51ce9061
commit f5b4a9c3ab
2 changed files with 149 additions and 25 deletions

View File

@ -53,6 +53,11 @@ comma-sperated list with no space: 0,1. Ranges of CPUs are specified with -: 0-2
In per-thread mode, this option is ignored. The -a option is still necessary
to activate system-wide monitoring. Default is to count on all CPUs.
-A::
--no-aggr::
Do not aggregate counts across all monitored CPUs in system-wide mode (-a).
This option is only valid in system-wide mode.
EXAMPLES
--------

View File

@ -75,6 +75,7 @@ static int run_idx = 0;
static int run_count = 1;
static bool no_inherit = false;
static bool scale = true;
static bool no_aggr = false;
static pid_t target_pid = -1;
static pid_t target_tid = -1;
static pid_t *all_tids = NULL;
@ -89,6 +90,12 @@ static int *fd[MAX_NR_CPUS][MAX_COUNTERS];
static int event_scaled[MAX_COUNTERS];
static struct {
u64 val;
u64 ena;
u64 run;
} cpu_counts[MAX_NR_CPUS][MAX_COUNTERS];
static volatile int done = 0;
struct stats
@ -136,10 +143,10 @@ static double stddev_stats(struct stats *stats)
}
struct stats event_res_stats[MAX_COUNTERS][3];
struct stats runtime_nsecs_stats;
struct stats runtime_nsecs_stats[MAX_NR_CPUS];
struct stats runtime_cycles_stats[MAX_NR_CPUS];
struct stats runtime_branches_stats[MAX_NR_CPUS];
struct stats walltime_nsecs_stats;
struct stats runtime_cycles_stats;
struct stats runtime_branches_stats;
#define MATCH_EVENT(t, c, counter) \
(attrs[counter].type == PERF_TYPE_##t && \
@ -205,8 +212,9 @@ static inline int nsec_counter(int counter)
/*
* Read out the results of a single counter:
* aggregate counts across CPUs in system-wide mode
*/
static void read_counter(int counter)
static void read_counter_aggr(int counter)
{
u64 count[3], single_count[3];
int cpu;
@ -264,11 +272,58 @@ static void read_counter(int counter)
* Save the full runtime - to allow normalization during printout:
*/
if (MATCH_EVENT(SOFTWARE, SW_TASK_CLOCK, counter))
update_stats(&runtime_nsecs_stats, count[0]);
update_stats(&runtime_nsecs_stats[0], count[0]);
if (MATCH_EVENT(HARDWARE, HW_CPU_CYCLES, counter))
update_stats(&runtime_cycles_stats, count[0]);
update_stats(&runtime_cycles_stats[0], count[0]);
if (MATCH_EVENT(HARDWARE, HW_BRANCH_INSTRUCTIONS, counter))
update_stats(&runtime_branches_stats, count[0]);
update_stats(&runtime_branches_stats[0], count[0]);
}
/*
* Read out the results of a single counter:
* do not aggregate counts across CPUs in system-wide mode
*/
static void read_counter(int counter)
{
u64 count[3];
int cpu;
size_t res, nv;
count[0] = count[1] = count[2] = 0;
nv = scale ? 3 : 1;
for (cpu = 0; cpu < nr_cpus; cpu++) {
if (fd[cpu][counter][0] < 0)
continue;
res = read(fd[cpu][counter][0], count, nv * sizeof(u64));
assert(res == nv * sizeof(u64));
close(fd[cpu][counter][0]);
fd[cpu][counter][0] = -1;
if (scale) {
if (count[2] == 0) {
count[0] = 0;
} else if (count[2] < count[1]) {
count[0] = (unsigned long long)
((double)count[0] * count[1] / count[2] + 0.5);
}
}
cpu_counts[cpu][counter].val = count[0]; /* scaled count */
cpu_counts[cpu][counter].ena = count[1];
cpu_counts[cpu][counter].run = count[2];
if (MATCH_EVENT(SOFTWARE, SW_TASK_CLOCK, counter))
update_stats(&runtime_nsecs_stats[cpu], count[0]);
if (MATCH_EVENT(HARDWARE, HW_CPU_CYCLES, counter))
update_stats(&runtime_cycles_stats[cpu], count[0]);
if (MATCH_EVENT(HARDWARE, HW_BRANCH_INSTRUCTIONS, counter))
update_stats(&runtime_branches_stats[cpu], count[0]);
}
}
static int run_perf_stat(int argc __used, const char **argv)
@ -362,9 +417,13 @@ static int run_perf_stat(int argc __used, const char **argv)
update_stats(&walltime_nsecs_stats, t1 - t0);
for (counter = 0; counter < nr_counters; counter++)
read_counter(counter);
if (no_aggr) {
for (counter = 0; counter < nr_counters; counter++)
read_counter(counter);
} else {
for (counter = 0; counter < nr_counters; counter++)
read_counter_aggr(counter);
}
return WEXITSTATUS(status);
}
@ -377,11 +436,15 @@ static void print_noise(int counter, double avg)
100 * stddev_stats(&event_res_stats[counter][0]) / avg);
}
static void nsec_printout(int counter, double avg)
static void nsec_printout(int cpu, int counter, double avg)
{
double msecs = avg / 1e6;
fprintf(stderr, " %18.6f %-24s", msecs, event_name(counter));
if (no_aggr)
fprintf(stderr, "CPU%-4d %18.6f %-24s",
cpumap[cpu], msecs, event_name(counter));
else
fprintf(stderr, " %18.6f %-24s", msecs, event_name(counter));
if (MATCH_EVENT(SOFTWARE, SW_TASK_CLOCK, counter)) {
fprintf(stderr, " # %10.3f CPUs ",
@ -389,33 +452,41 @@ static void nsec_printout(int counter, double avg)
}
}
static void abs_printout(int counter, double avg)
static void abs_printout(int cpu, int counter, double avg)
{
double total, ratio = 0.0;
char cpustr[16] = { '\0', };
if (no_aggr)
sprintf(cpustr, "CPU%-4d", cpumap[cpu]);
else
cpu = 0;
if (big_num)
fprintf(stderr, " %'18.0f %-24s", avg, event_name(counter));
fprintf(stderr, "%s %'18.0f %-24s",
cpustr, avg, event_name(counter));
else
fprintf(stderr, " %18.0f %-24s", avg, event_name(counter));
fprintf(stderr, "%s %18.0f %-24s",
cpustr, avg, event_name(counter));
if (MATCH_EVENT(HARDWARE, HW_INSTRUCTIONS, counter)) {
total = avg_stats(&runtime_cycles_stats);
total = avg_stats(&runtime_cycles_stats[cpu]);
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);
runtime_branches_stats[cpu].n != 0) {
total = avg_stats(&runtime_branches_stats[cpu]);
if (total)
ratio = avg * 100 / total;
fprintf(stderr, " # %10.3f %% ", ratio);
} else if (runtime_nsecs_stats.n != 0) {
total = avg_stats(&runtime_nsecs_stats);
} else if (runtime_nsecs_stats[cpu].n != 0) {
total = avg_stats(&runtime_nsecs_stats[cpu]);
if (total)
ratio = 1000.0 * avg / total;
@ -426,8 +497,9 @@ static void abs_printout(int counter, double avg)
/*
* Print out the results of a single counter:
* aggregated counts in system-wide mode
*/
static void print_counter(int counter)
static void print_counter_aggr(int counter)
{
double avg = avg_stats(&event_res_stats[counter][0]);
int scaled = event_scaled[counter];
@ -439,9 +511,9 @@ static void print_counter(int counter)
}
if (nsec_counter(counter))
nsec_printout(counter, avg);
nsec_printout(-1, counter, avg);
else
abs_printout(counter, avg);
abs_printout(-1, counter, avg);
print_noise(counter, avg);
@ -458,6 +530,42 @@ static void print_counter(int counter)
fprintf(stderr, "\n");
}
/*
* Print out the results of a single counter:
* does not use aggregated count in system-wide
*/
static void print_counter(int counter)
{
u64 ena, run, val;
int cpu;
for (cpu = 0; cpu < nr_cpus; cpu++) {
val = cpu_counts[cpu][counter].val;
ena = cpu_counts[cpu][counter].ena;
run = cpu_counts[cpu][counter].run;
if (run == 0 || ena == 0) {
fprintf(stderr, "CPU%-4d %18s %-24s", cpumap[cpu],
"<not counted>", event_name(counter));
fprintf(stderr, "\n");
continue;
}
if (nsec_counter(counter))
nsec_printout(cpu, counter, val);
else
abs_printout(cpu, counter, val);
print_noise(counter, 1.0);
if (run != ena) {
fprintf(stderr, " (scaled from %.2f%%)",
100.0 * run / ena);
}
fprintf(stderr, "\n");
}
}
static void print_stat(int argc, const char **argv)
{
int i, counter;
@ -480,8 +588,13 @@ static void print_stat(int argc, const char **argv)
fprintf(stderr, " (%d runs)", run_count);
fprintf(stderr, ":\n\n");
for (counter = 0; counter < nr_counters; counter++)
print_counter(counter);
if (no_aggr) {
for (counter = 0; counter < nr_counters; counter++)
print_counter(counter);
} else {
for (counter = 0; counter < nr_counters; counter++)
print_counter_aggr(counter);
}
fprintf(stderr, "\n");
fprintf(stderr, " %18.9f seconds time elapsed",
@ -545,6 +658,8 @@ static const struct option options[] = {
"print large numbers with thousands\' separators"),
OPT_STRING('C', "cpu", &cpu_list, "cpu",
"list of cpus to monitor in system-wide"),
OPT_BOOLEAN('A', "no-aggr", &no_aggr,
"disable CPU count aggregation"),
OPT_END()
};
@ -562,6 +677,10 @@ int cmd_stat(int argc, const char **argv, const char *prefix __used)
if (run_count <= 0)
usage_with_options(stat_usage, options);
/* no_aggr is for system-wide only */
if (no_aggr && !system_wide)
usage_with_options(stat_usage, options);
/* 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));