Commit 3cdad0a5 authored by Ilpo Järvinen's avatar Ilpo Järvinen Committed by Shuah Khan
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selftests/resctrl: Convert perf related globals to locals 



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: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: default avatarReinette Chatre <reinette.chatre@intel.com>
Signed-off-by: default avatarShuah Khan <skhan@linuxfoundation.org>
parent 038ce802

tools/testing/selftests/resctrl/cache.c

+40 −32
Original line number Diff line number Diff line
@@ -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;