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perf stat: Continue even on counter creation error 

Before:

 $ perf stat ~/hackbench 5

 error: syscall returned with -1 (No such device)

After:

 $ perf stat ~/hackbench 5
 Time: 1.640

 Performance counter stats for '/home/mingo/hackbench 5':

    6524.570382  task-clock-ticks     #       3.838 CPU utilization factor
          35704  context-switches     #       0.005 M/sec
            191  CPU-migrations       #       0.000 M/sec
           8958  page-faults          #       0.001 M/sec
  <not counted>  cycles
  <not counted>  instructions
  <not counted>  cache-references
  <not counted>  cache-misses

 Wall-clock time elapsed:  1699.999995 msecs

Also add -v (--verbose) option to allow the printing of failed
counter opens.

Plus dont print 'inf' if wall-time is zero (due to jiffies granularity),
instead skip the printing of the CPU utilization factor.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Ingo Molnar 2009-06-07 17:06:46 +02:00
parent 2f01190aa6
commit 743ee1f804
1 changed files with 17 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

31
tools/perf/builtin-stat.c
View File

@ -59,6 +59,7 @@ static struct perf_counter_attr default_attrs[MAX_COUNTERS] = {
static int system_wide = 0;
static int inherit = 1;
static int verbose = 0;
static int fd[MAX_NR_CPUS][MAX_COUNTERS];
@ -83,7 +84,7 @@ static __u64 event_scaled[MAX_COUNTERS];
static __u64 runtime_nsecs;
static __u64 walltime_nsecs;
static void create_perfstat_counter(int counter)
static void create_perf_stat_counter(int counter)
{
struct perf_counter_attr *attr = attrs + counter;
@ -95,10 +96,8 @@ static void create_perfstat_counter(int counter)
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) {
printf("Error: counter %d, sys_perf_counter_open() syscall returned with %d (%s)\n", counter, fd[cpu][counter], strerror(errno));
}
}
} else {
@ -106,10 +105,8 @@ static void create_perfstat_counter(int counter)
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);
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));
}
}
}
@ -147,6 +144,9 @@ static void read_counter(int counter)
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));
@ -204,8 +204,9 @@ static void print_counter(int 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);
if (walltime_nsecs)
fprintf(stderr, " # %11.3f CPU utilization factor",
(double)count[0] / (double)walltime_nsecs);
}
} else {
fprintf(stderr, " %14Ld %-20s",
@ -220,7 +221,7 @@ static void print_counter(int counter)
fprintf(stderr, "\n");
}
static int do_perfstat(int argc, const char **argv)
static int do_perf_stat(int argc, const char **argv)
{
unsigned long long t0, t1;
int counter;
@ -232,7 +233,7 @@ static int do_perfstat(int argc, const char **argv)
nr_cpus = 1;
for (counter = 0; counter < nr_counters; counter++)
create_perfstat_counter(counter);
create_perf_stat_counter(counter);
/*
* Enable counters and exec the command:
@ -305,6 +306,8 @@ static const struct option options[] = {
"system-wide collection from all CPUs"),
OPT_BOOLEAN('S', "scale", &scale,
"scale/normalize counters"),
OPT_BOOLEAN('v', "verbose", &verbose,
"be more verbose (show counter open errors, etc)"),
OPT_END()
};
@ -335,5 +338,5 @@ int cmd_stat(int argc, const char **argv, const char *prefix)
signal(SIGALRM, skip_signal);
signal(SIGABRT, skip_signal);
return do_perfstat(argc, argv);
return do_perf_stat(argc, argv);
}