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| author | Yogesh Tillu <yogesh.tillu@linaro.org> | 2015-07-28 14:54:15 +0530 |
|---|---|---|
| committer | Yogesh Tillu <yogesh.tillu@linaro.org> | 2015-07-30 17:25:00 +0530 |
| commit | c40a41e0ea3d6bd3fbad8eecc89aece011e71f09 (patch) | |
| tree | 64476bfb294a18d0e9b6d8343d1d1c52f7fac579 | |
| parent | a8b75a4ec9ebfd1b2bb141aca08ff2adaef5b578 (diff) | |
perf_ev_open: Added support for passing sample_period as argument
NOTE: To reduce number of overflow occurance while testing with
perf hw counter, we can tune sample_period value as parameter.
Signed-off-by: Yogesh Tillu <yogesh.tillu@linaro.org>
Reviewed-by: Anders Roxell <anders.roxell@linaro.org>
| -rw-r--r-- | perf_ev_open.c | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/perf_ev_open.c b/perf_ev_open.c index b8cf681..9b59a37 100644 --- a/perf_ev_open.c +++ b/perf_ev_open.c @@ -31,7 +31,7 @@ static void sigio_handler(int signo, siginfo_t *info, void *uc) overflow = overflow + 1; } -static int counter_init(unsigned int counter) +static int counter_init(unsigned int counter,long unsigned int sample) { static struct perf_event_attr attr; attr.type = PERF_TYPE_HARDWARE; @@ -49,7 +49,7 @@ static int counter_init(unsigned int counter) printf("Error: SIGIO signal handler %s\n",strerror(errno)); } - attr.sample_period = 1000000; + attr.sample_period = sample; attr.sample_type = PERF_SAMPLE_IP; attr.wakeup_events = 1; attr.config = counter; @@ -97,8 +97,9 @@ void print_usage(char *argv) "Refer to 'enum perf_hw_id'[file <linux/perf_event.h>] for hw\n" "counter enum value in range of 0 to PERF_COUNT_HW_MAX\n" "-n\t Length size array will implement busyloop\n" + "-s\t Sample period [> 1000000 samples]\n" "e.g.\n" - "\t%s -c 0 -n 64\n", argv, argv, argv); + "\t%s -c 0 -n 64 -s 1000000\n", argv, argv, argv); } int main(int ac, char *argv[]) @@ -110,8 +111,9 @@ int main(int ac, char *argv[]) int *a = NULL; int *b = NULL; int i, pre_loop_res, post_loop_res, sum = 0; + unsigned long s_period = 1000000; - while ((option = getopt(ac, argv, "c:n:")) != -1) { + while ((option = getopt(ac, argv, "c:n:s:")) != -1) { switch (option) { case 'c': cnt = atoi(optarg); @@ -119,6 +121,9 @@ int main(int ac, char *argv[]) case 'n': len = atoi(optarg); break; + case 's': + s_period = atoi(optarg); + break; default: print_usage(argv[0]); exit(EXIT_FAILURE); @@ -130,7 +135,7 @@ int main(int ac, char *argv[]) exit(EXIT_FAILURE); } - if (counter_init(cnt) < 0) { + if (counter_init(cnt, s_period) < 0) { printf("Error: Counter Invalid\n"); print_usage(argv[0]); exit(EXIT_FAILURE); |