Perf event handling has functions that are the sole caller of another perf event handling related function: - reset_enable_llc_perf() calls perf_event_open_llc_miss() - reset_enable_llc_perf() calls ioctl_perf_event_ioc_reset_enable() - measure_llc_perf() calls get_llc_perf()
Remove the extra layer of calls to make the code easier to follow by moving the code into the calling function.
In addition, converts print_results_cache() unsigned long parameter to __u64 that matches the type coming from perf.
Signed-off-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com --- tools/testing/selftests/resctrl/cache.c | 86 +++++++------------------ 1 file changed, 25 insertions(+), 61 deletions(-)
diff --git a/tools/testing/selftests/resctrl/cache.c b/tools/testing/selftests/resctrl/cache.c index d39ef4eebc37..208af1ecae28 100644 --- a/tools/testing/selftests/resctrl/cache.c +++ b/tools/testing/selftests/resctrl/cache.c @@ -29,25 +29,6 @@ static void initialize_perf_event_attr(void) pea_llc_miss.disabled = 1; }
-static void ioctl_perf_event_ioc_reset_enable(void) -{ - ioctl(fd_lm, PERF_EVENT_IOC_RESET, 0); - ioctl(fd_lm, PERF_EVENT_IOC_ENABLE, 0); -} - -static int perf_event_open_llc_miss(pid_t pid, int cpu_no) -{ - fd_lm = perf_event_open(&pea_llc_miss, pid, cpu_no, -1, - PERF_FLAG_FD_CLOEXEC); - if (fd_lm == -1) { - perror("Error opening leader"); - ctrlc_handler(0, NULL, NULL); - return -1; - } - - return 0; -} - static void initialize_llc_perf(void) { memset(&pea_llc_miss, 0, sizeof(struct perf_event_attr)); @@ -63,42 +44,16 @@ static void initialize_llc_perf(void)
static int reset_enable_llc_perf(pid_t pid, int cpu_no) { - int ret = 0; - - ret = perf_event_open_llc_miss(pid, cpu_no); - if (ret < 0) - return ret; - - /* Start counters to log values */ - ioctl_perf_event_ioc_reset_enable(); - - return 0; -} - -/* - * get_llc_perf: llc cache miss through perf events - * @llc_perf_miss: LLC miss counter that is filled on success - * - * Perf events like HW_CACHE_MISSES could be used to validate number of - * cache lines allocated. - * - * Return: =0 on success. <0 on failure. - */ -static int get_llc_perf(__u64 *llc_perf_miss) -{ - int ret; - - /* Stop counters after one span to get miss rate */ - - ioctl(fd_lm, PERF_EVENT_IOC_DISABLE, 0); - - ret = read(fd_lm, &rf_cqm, sizeof(struct read_format)); - if (ret == -1) { - perror("Could not get llc misses through perf"); + fd_lm = perf_event_open(&pea_llc_miss, pid, cpu_no, -1, PERF_FLAG_FD_CLOEXEC); + if (fd_lm == -1) { + perror("Error opening leader"); + ctrlc_handler(0, NULL, NULL); return -1; }
- *llc_perf_miss = rf_cqm.values[0].value; + /* Start counters to log values */ + ioctl(fd_lm, PERF_EVENT_IOC_RESET, 0); + ioctl(fd_lm, PERF_EVENT_IOC_ENABLE, 0);
return 0; } @@ -166,20 +121,29 @@ static int print_results_cache(char *filename, int bm_pid, __u64 llc_value) return 0; }
+/* + * measure_llc_perf: measure perf events + * @bm_pid: child pid that runs benchmark + * + * Measure things like cache misses from perf events. + * + * Return: =0 on success. <0 on failure. + */ static int measure_llc_perf(struct resctrl_val_param *param, int bm_pid) { - __u64 llc_perf_miss = 0; int ret;
- /* - * Measure cache miss from perf. - */ - ret = get_llc_perf(&llc_perf_miss); - if (ret < 0) - return ret; + /* Stop counters after one span to get miss rate */ + ioctl(fd_lm, PERF_EVENT_IOC_DISABLE, 0);
- ret = print_results_cache(param->filename, bm_pid, llc_perf_miss); - return ret; + ret = read(fd_lm, &rf_cqm, sizeof(struct read_format)); + close(fd_lm); + if (ret == -1) { + perror("Could not get perf value"); + return -1; + } + + return print_results_cache(param->filename, bm_pid, rf_cqm.values[0].value); }
int measure_llc_resctrl(struct resctrl_val_param *param, int bm_pid)