selftests/resctrl: Add Cache Allocation Technology (CAT) selftest (790bf585) · Commits · 戴 / test

tools/testing/selftests/resctrl/cache.c

+174 −1

Original line number	Diff line number	Diff line
		@@ -10,8 +10,105 @@ struct read_format {
		} values[2];
		};

		static struct perf_event_attr pea_llc_miss;
		static struct read_format rf_cqm;
		static int fd_lm;
		char llc_occup_path[1024];

		static void initialize_perf_event_attr(void)
		{
		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;
		}

		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 int initialize_llc_perf(void)
		{
		memset(&pea_llc_miss, 0, sizeof(struct perf_event_attr));
		memset(&rf_cqm, 0, sizeof(struct read_format));

		/* Initialize perf_event_attr structures for HW_CACHE_MISSES */
		initialize_perf_event_attr();

		pea_llc_miss.config = PERF_COUNT_HW_CACHE_MISSES;

		rf_cqm.nr = 1;

		return 0;
		}

		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
		* @cpu_no: CPU number that the benchmark PID is binded to
		*
		* 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(unsigned long *llc_perf_miss)
		{
		__u64 total_misses;

		/* Stop counters after one span to get miss rate */

		ioctl(fd_lm, PERF_EVENT_IOC_DISABLE, 0);

		if (read(fd_lm, &rf_cqm, sizeof(struct read_format)) == -1) {
		perror("Could not get llc misses through perf");

		return -1;
		}

		total_misses = rf_cqm.values[0].value;

		close(fd_lm);

		*llc_perf_miss = total_misses;

		return 0;
		}

		/*
		* Get LLC Occupancy as reported by RESCTRL FS
		* For CQM,
		@@ -79,9 +176,19 @@ static int print_results_cache(char *filename, int bm_pid,

		int measure_cache_vals(struct resctrl_val_param *param, int bm_pid)
		{
		unsigned long llc_occu_resc = 0, llc_value = 0;
		unsigned long llc_perf_miss = 0, llc_occu_resc = 0, llc_value = 0;
		int ret;

		/*
		* Measure cache miss from perf.
		*/
		if (!strcmp(param->resctrl_val, "cat")) {
		ret = get_llc_perf(&llc_perf_miss);
		if (ret < 0)
		return ret;
		llc_value = llc_perf_miss;
		}

		/*
		* Measure llc occupancy from resctrl.
		*/
		@@ -97,3 +204,69 @@ int measure_cache_vals(struct resctrl_val_param *param, int bm_pid)

		return 0;
		}

		/*
		* cache_val: execute benchmark and measure LLC occupancy resctrl
		* and perf cache miss for the benchmark
		* @param: parameters passed to cache_val()
		*
		* Return: 0 on success. non-zero on failure.
		*/
		int cat_val(struct resctrl_val_param *param)
		{
		int malloc_and_init_memory = 1, memflush = 1, operation = 0, ret = 0;
		char *resctrl_val = param->resctrl_val;
		pid_t bm_pid;

		if (strcmp(param->filename, "") == 0)
		sprintf(param->filename, "stdio");

		bm_pid = getpid();

		/* Taskset benchmark to specified cpu */
		ret = taskset_benchmark(bm_pid, param->cpu_no);
		if (ret)
		return ret;

		/* Write benchmark to specified con_mon grp, mon_grp in resctrl FS*/
		ret = write_bm_pid_to_resctrl(bm_pid, param->ctrlgrp, param->mongrp,
		resctrl_val);
		if (ret)
		return ret;

		if ((strcmp(resctrl_val, "cat") == 0)) {
		ret = initialize_llc_perf();
		if (ret)
		return ret;
		}

		/* Test runs until the callback setup() tells the test to stop. */
		while (1) {
		if (strcmp(resctrl_val, "cat") == 0) {
		ret = param->setup(1, param);
		if (ret) {
		ret = 0;
		break;
		}
		ret = reset_enable_llc_perf(bm_pid, param->cpu_no);
		if (ret)
		break;

		if (run_fill_buf(param->span, malloc_and_init_memory,
		memflush, operation, resctrl_val)) {
		fprintf(stderr, "Error-running fill buffer\n");
		ret = -1;
		break;
		}

		sleep(1);
		ret = measure_cache_vals(param, bm_pid);
		if (ret)
		break;
		} else {
		break;
		}
		}

		return ret;
		}

tools/testing/selftests/resctrl/cat_test.c

0 → 100644

+250 −0

Original line number	Diff line number	Diff line
		// SPDX-License-Identifier: GPL-2.0
		/*
		* Cache Allocation Technology (CAT) test
		*
		* Copyright (C) 2018 Intel Corporation
		*
		* Authors:
		* Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>,
		* Fenghua Yu <fenghua.yu@intel.com>
		*/
		#include "resctrl.h"
		#include <unistd.h>

		#define RESULT_FILE_NAME1 "result_cat1"
		#define RESULT_FILE_NAME2 "result_cat2"
		#define NUM_OF_RUNS 5
		#define MAX_DIFF_PERCENT 4
		#define MAX_DIFF 1000000

		int count_of_bits;
		char cbm_mask[256];
		unsigned long long_mask;
		unsigned long cache_size;

		/*
		* Change schemata. Write schemata to specified
		* con_mon grp, mon_grp in resctrl FS.
		* Run 5 times in order to get average values.
		*/
		static int cat_setup(int num, ...)
		{
		struct resctrl_val_param *p;
		char schemata[64];
		va_list param;
		int ret = 0;

		va_start(param, num);
		p = va_arg(param, struct resctrl_val_param *);
		va_end(param);

		/* Run NUM_OF_RUNS times */
		if (p->num_of_runs >= NUM_OF_RUNS)
		return -1;

		if (p->num_of_runs == 0) {
		sprintf(schemata, "%lx", p->mask);
		ret = write_schemata(p->ctrlgrp, schemata, p->cpu_no,
		p->resctrl_val);
		}
		p->num_of_runs++;

		return ret;
		}

		static void show_cache_info(unsigned long sum_llc_perf_miss, int no_of_bits,
		unsigned long span)
		{
		unsigned long allocated_cache_lines = span / 64;
		unsigned long avg_llc_perf_miss = 0;
		float diff_percent;

		avg_llc_perf_miss = sum_llc_perf_miss / (NUM_OF_RUNS - 1);
		diff_percent = ((float)allocated_cache_lines - avg_llc_perf_miss) /
		allocated_cache_lines * 100;

		printf("%sok CAT: cache miss rate within %d%%\n",
		abs((int)diff_percent) > MAX_DIFF_PERCENT ? "not " : "",
		MAX_DIFF_PERCENT);
		tests_run++;
		printf("# Percent diff=%d\n", abs((int)diff_percent));
		printf("# Number of bits: %d\n", no_of_bits);
		printf("# Avg_llc_perf_miss: %lu\n", avg_llc_perf_miss);
		printf("# Allocated cache lines: %lu\n", allocated_cache_lines);
		}

		static int check_results(struct resctrl_val_param *param)
		{
		char *token_array[8], temp[512];
		unsigned long sum_llc_perf_miss = 0;
		int runs = 0, no_of_bits = 0;
		FILE *fp;

		printf("# Checking for pass/fail\n");
		fp = fopen(param->filename, "r");
		if (!fp) {
		perror("# Cannot open file");

		return errno;
		}

		while (fgets(temp, sizeof(temp), fp)) {
		char *token = strtok(temp, ":\t");
		int fields = 0;

		while (token) {
		token_array[fields++] = token;
		token = strtok(NULL, ":\t");
		}
		/*
		* Discard the first value which is inaccurate due to monitoring
		* setup transition phase.
		*/
		if (runs > 0)
		sum_llc_perf_miss += strtoul(token_array[3], NULL, 0);
		runs++;
		}

		fclose(fp);
		no_of_bits = count_bits(param->mask);

		show_cache_info(sum_llc_perf_miss, no_of_bits, param->span);

		return 0;
		}

		void cat_test_cleanup(void)
		{
		remove(RESULT_FILE_NAME1);
		remove(RESULT_FILE_NAME2);
		}

		int cat_perf_miss_val(int cpu_no, int n, char *cache_type)
		{
		unsigned long l_mask, l_mask_1;
		int ret, pipefd[2], sibling_cpu_no;
		char pipe_message;
		pid_t bm_pid;

		cache_size = 0;

		ret = remount_resctrlfs(true);
		if (ret)
		return ret;

		if (!validate_resctrl_feature_request("cat"))
		return -1;

		/* Get default cbm mask for L3/L2 cache */
		ret = get_cbm_mask(cache_type);
		if (ret)
		return ret;

		long_mask = strtoul(cbm_mask, NULL, 16);

		/* Get L3/L2 cache size */
		ret = get_cache_size(cpu_no, cache_type, &cache_size);
		if (ret)
		return ret;
		printf("cache size :%lu\n", cache_size);

		/* Get max number of bits from default-cabm mask */
		count_of_bits = count_bits(long_mask);

		if (n < 1 \|\| n > count_of_bits - 1) {
		printf("Invalid input value for no_of_bits n!\n");
		printf("Please Enter value in range 1 to %d\n",
		count_of_bits - 1);
		return -1;
		}

		/* Get core id from same socket for running another thread */
		sibling_cpu_no = get_core_sibling(cpu_no);
		if (sibling_cpu_no < 0)
		return -1;

		struct resctrl_val_param param = {
		.resctrl_val = "cat",
		.cpu_no = cpu_no,
		.mum_resctrlfs = 0,
		.setup = cat_setup,
		};

		l_mask = long_mask >> n;
		l_mask_1 = ~l_mask & long_mask;

		/* Set param values for parent thread which will be allocated bitmask
		* with (max_bits - n) bits
		*/
		param.span = cache_size * (count_of_bits - n) / count_of_bits;
		strcpy(param.ctrlgrp, "c2");
		strcpy(param.mongrp, "m2");
		strcpy(param.filename, RESULT_FILE_NAME2);
		param.mask = l_mask;
		param.num_of_runs = 0;

		if (pipe(pipefd)) {
		perror("# Unable to create pipe");
		return errno;
		}

		bm_pid = fork();

		/* Set param values for child thread which will be allocated bitmask
		* with n bits
		*/
		if (bm_pid == 0) {
		param.mask = l_mask_1;
		strcpy(param.ctrlgrp, "c1");
		strcpy(param.mongrp, "m1");
		param.span = cache_size * n / count_of_bits;
		strcpy(param.filename, RESULT_FILE_NAME1);
		param.num_of_runs = 0;
		param.cpu_no = sibling_cpu_no;
		}

		remove(param.filename);

		ret = cat_val(&param);
		if (ret)
		return ret;

		ret = check_results(&param);
		if (ret)
		return ret;

		if (bm_pid == 0) {
		/* Tell parent that child is ready */
		close(pipefd[0]);
		pipe_message = 1;
		if (write(pipefd[1], &pipe_message, sizeof(pipe_message)) <
		sizeof(pipe_message)) {
		close(pipefd[1]);
		perror("# failed signaling parent process");
		return errno;
		}

		close(pipefd[1]);
		while (1)
		;
		} else {
		/* Parent waits for child to be ready. */
		close(pipefd[1]);
		pipe_message = 0;
		while (pipe_message != 1) {
		if (read(pipefd[0], &pipe_message,
		sizeof(pipe_message)) < sizeof(pipe_message)) {
		perror("# failed reading from child process");
		break;
		}
		}
		close(pipefd[0]);
		kill(bm_pid, SIGKILL);
		}

		cat_test_cleanup();
		if (bm_pid)
		umount_resctrlfs();

		return 0;
		}

tools/testing/selftests/resctrl/fill_buf.c

+8 −2

Original line number	Diff line number	Diff line
		@@ -113,8 +113,11 @@ static int fill_cache_read(unsigned char start_ptr, unsigned char end_ptr,
		int ret = 0;
		FILE *fp;

		while (1)
		while (1) {
		ret = fill_one_span_read(start_ptr, end_ptr);
		if (!strcmp(resctrl_val, "cat"))
		break;
		}

		/* Consume read result so that reading memory is not optimized out. */
		fp = fopen("/dev/null", "w");
		@@ -129,8 +132,11 @@ static int fill_cache_read(unsigned char start_ptr, unsigned char end_ptr,
		static int fill_cache_write(unsigned char start_ptr, unsigned char end_ptr,
		char *resctrl_val)
		{
		while (1)
		while (1) {
		fill_one_span_write(start_ptr, end_ptr);
		if (!strcmp(resctrl_val, "cat"))
		break;
		}

		return 0;
		}

tools/testing/selftests/resctrl/resctrl.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -94,6 +94,9 @@ void mba_test_cleanup(void);
		int get_cbm_mask(char *cache_type);
		int get_cache_size(int cpu_no, char cache_type, unsigned long cache_size);
		void ctrlc_handler(int signum, siginfo_t info, void ptr);
		int cat_val(struct resctrl_val_param *param);
		void cat_test_cleanup(void);
		int cat_perf_miss_val(int cpu_no, int no_of_bits, char *cache_type);
		int cqm_resctrl_val(int cpu_no, int n, char **benchmark_cmd);
		unsigned int count_bits(unsigned long n);
		void cqm_test_cleanup(void);

tools/testing/selftests/resctrl/resctrl_tests.c

+14 −1

Original line number	Diff line number	Diff line
		@@ -19,7 +19,7 @@ static void cmd_help(void)
		printf("\t-b benchmark_cmd [options]: run specified benchmark for MBM, MBA and CQM");
		printf("\t default benchmark is builtin fill_buf\n");
		printf("\t-t test list: run tests specified in the test list, ");
		printf("e.g. -t mbm, mba, cqm\n");
		printf("e.g. -t mbm, mba, cqm, cat\n");
		printf("\t-n no_of_bits: run cache tests using specified no of bits in cache bit mask\n");
		printf("\t-p cpu_no: specify CPU number to run the test. 1 is default\n");
		printf("\t-h: help\n");
		@@ -30,6 +30,7 @@ void tests_cleanup(void)
		mbm_test_cleanup();
		mba_test_cleanup();
		cqm_test_cleanup();
		cat_test_cleanup();
		}

		int main(int argc, char **argv)
		@@ -39,6 +40,7 @@ int main(int argc, char **argv)
		char *benchmark_cmd[BENCHMARK_ARGS], bw_report[64], bm_type[64];
		char benchmark_cmd_area[BENCHMARK_ARGS][BENCHMARK_ARG_SIZE];
		int ben_ind, ben_count;
		bool cat_test = true;

		for (i = 0; i < argc; i++) {
		if (strcmp(argv[i], "-b") == 0) {
		@@ -60,6 +62,7 @@ int main(int argc, char **argv)
		mbm_test = false;
		mba_test = false;
		cqm_test = false;
		cat_test = false;
		while (token) {
		if (!strcmp(token, "mbm")) {
		mbm_test = true;
		@@ -67,6 +70,8 @@ int main(int argc, char **argv)
		mba_test = true;
		} else if (!strcmp(token, "cqm")) {
		cqm_test = true;
		} else if (!strcmp(token, "cat")) {
		cat_test = true;
		} else {
		printf("invalid argument\n");

		@@ -159,6 +164,14 @@ int main(int argc, char **argv)
		tests_run++;
		}

		if (cat_test) {
		printf("# Starting CAT test ...\n");
		res = cat_perf_miss_val(cpu_no, no_of_bits, "L3");
		printf("%sok CAT: test\n", res ? "not " : "");
		tests_run++;
		cat_test_cleanup();
		}

		printf("1..%d\n", tests_run);

		return 0;

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