Perf related variables pea_llc_miss, pe_read, and pe_fd are globals in cache.c.
Convert them to locals for better scoping and make pea_llc_miss simpler by renaming it to pea. Make close(pe_fd) handling easier to understand by doing it inside cat_val().
Make also sizeof()s use safer way to determine the right struct.
Signed-off-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com Reviewed-by: Reinette Chatre reinette.chatre@intel.com --- tools/testing/selftests/resctrl/cache.c | 72 ++++++++++++++----------- 1 file changed, 40 insertions(+), 32 deletions(-)
diff --git a/tools/testing/selftests/resctrl/cache.c b/tools/testing/selftests/resctrl/cache.c index 58ee6f6b0edf..335415eaa406 100644 --- a/tools/testing/selftests/resctrl/cache.c +++ b/tools/testing/selftests/resctrl/cache.c @@ -10,51 +10,50 @@ struct perf_event_read { } values[2]; };
-static struct perf_event_attr pea_llc_miss; -static struct perf_event_read pe_read; -static int pe_fd; char llc_occup_path[1024];
-static void perf_event_attr_initialize(__u64 config) +static void perf_event_attr_initialize(struct perf_event_attr *pea, __u64 config) { - memset(&pea_llc_miss, 0, sizeof(struct perf_event_attr)); - pea_llc_miss.type = PERF_TYPE_HARDWARE; - pea_llc_miss.size = sizeof(struct perf_event_attr); - pea_llc_miss.read_format = PERF_FORMAT_GROUP; - pea_llc_miss.exclude_kernel = 1; - pea_llc_miss.exclude_hv = 1; - pea_llc_miss.exclude_idle = 1; - pea_llc_miss.exclude_callchain_kernel = 1; - pea_llc_miss.inherit = 1; - pea_llc_miss.exclude_guest = 1; - pea_llc_miss.disabled = 1; - pea_llc_miss.config = config; + memset(pea, 0, sizeof(*pea)); + pea->type = PERF_TYPE_HARDWARE; + pea->size = sizeof(*pea); + pea->read_format = PERF_FORMAT_GROUP; + pea->exclude_kernel = 1; + pea->exclude_hv = 1; + pea->exclude_idle = 1; + pea->exclude_callchain_kernel = 1; + pea->inherit = 1; + pea->exclude_guest = 1; + pea->disabled = 1; + pea->config = config; }
/* Start counters to log values */ -static void perf_event_reset_enable(void) +static void perf_event_reset_enable(int pe_fd) { ioctl(pe_fd, PERF_EVENT_IOC_RESET, 0); ioctl(pe_fd, PERF_EVENT_IOC_ENABLE, 0); }
-static void perf_event_initialize_read_format(void) +static void perf_event_initialize_read_format(struct perf_event_read *pe_read) { - memset(&pe_read, 0, sizeof(struct perf_event_read)); - pe_read.nr = 1; + memset(pe_read, 0, sizeof(*pe_read)); + pe_read->nr = 1; }
-static int perf_open(pid_t pid, int cpu_no) +static int perf_open(struct perf_event_attr *pea, pid_t pid, int cpu_no) { - pe_fd = perf_event_open(&pea_llc_miss, pid, cpu_no, -1, PERF_FLAG_FD_CLOEXEC); + int pe_fd; + + pe_fd = perf_event_open(pea, pid, cpu_no, -1, PERF_FLAG_FD_CLOEXEC); if (pe_fd == -1) { ksft_perror("Error opening leader"); return -1; }
- perf_event_reset_enable(); + perf_event_reset_enable(pe_fd);
- return 0; + return pe_fd; }
/* @@ -131,20 +130,21 @@ static int print_results_cache(const char *filename, int bm_pid, __u64 llc_value * * Return: =0 on success. <0 on failure. */ -static int perf_event_measure(const char *filename, int bm_pid) +static int perf_event_measure(int pe_fd, struct perf_event_read *pe_read, + const char *filename, int bm_pid) { int ret;
/* Stop counters after one span to get miss rate */ ioctl(pe_fd, PERF_EVENT_IOC_DISABLE, 0);
- ret = read(pe_fd, &pe_read, sizeof(struct perf_event_read)); + ret = read(pe_fd, pe_read, sizeof(*pe_read)); if (ret == -1) { ksft_perror("Could not get perf value"); return -1; }
- return print_results_cache(filename, bm_pid, pe_read.values[0].value); + return print_results_cache(filename, bm_pid, pe_read->values[0].value); }
/* @@ -181,7 +181,10 @@ int cat_val(struct resctrl_val_param *param, size_t span) { int memflush = 1, operation = 0, ret = 0; char *resctrl_val = param->resctrl_val; + struct perf_event_read pe_read; + struct perf_event_attr pea; pid_t bm_pid; + int pe_fd;
if (strcmp(param->filename, "") == 0) sprintf(param->filename, "stdio"); @@ -199,8 +202,8 @@ int cat_val(struct resctrl_val_param *param, size_t span) if (ret) return ret;
- perf_event_attr_initialize(PERF_COUNT_HW_CACHE_MISSES); - perf_event_initialize_read_format(); + perf_event_attr_initialize(&pea, PERF_COUNT_HW_CACHE_MISSES); + perf_event_initialize_read_format(&pe_read);
/* Test runs until the callback setup() tells the test to stop. */ while (1) { @@ -211,9 +214,12 @@ int cat_val(struct resctrl_val_param *param, size_t span) } if (ret < 0) break; - ret = perf_open(bm_pid, param->cpu_no); - if (ret) + + pe_fd = perf_open(&pea, bm_pid, param->cpu_no); + if (pe_fd < 0) { + ret = -1; break; + }
if (run_fill_buf(span, memflush, operation, true)) { fprintf(stderr, "Error-running fill buffer\n"); @@ -222,9 +228,11 @@ int cat_val(struct resctrl_val_param *param, size_t span) }
sleep(1); - ret = perf_event_measure(param->filename, bm_pid); + ret = perf_event_measure(pe_fd, &pe_read, param->filename, bm_pid); if (ret) goto pe_close; + + close(pe_fd); }
return ret;