// SPDX-License-Identifier: GPL-2.0 #include <stdint.h>#include "resctrl.h" struct read_format {	__u64 nr;			/* The number of events */	struct {		__u64 value;		/* The value of the event */	} 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 void 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;} 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(unsigned long *llc_perf_miss){	__u64 total_misses;	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");		return -1;	} 	total_misses = rf_cqm.values[0].value;	*llc_perf_miss = total_misses; 	return 0;} /* * Get LLC Occupancy as reported by RESCTRL FS * For CMT, * 1. If con_mon grp and mon grp given, then read from mon grp in * con_mon grp * 2. If only con_mon grp given, then read from con_mon grp * 3. If both not given, then read from root con_mon grp * For CAT, * 1. If con_mon grp given, then read from it * 2. If con_mon grp not given, then read from root con_mon grp * * Return: =0 on success.  <0 on failure. */static int get_llc_occu_resctrl(unsigned long *llc_occupancy){	FILE *fp; 	fp = fopen(llc_occup_path, "r");	if (!fp) {		perror("Failed to open results file"); 		return errno;	}	if (fscanf(fp, "%lu", llc_occupancy) <= 0) {		perror("Could not get llc occupancy");		fclose(fp); 		return -1;	}	fclose(fp); 	return 0;} /* * print_results_cache:	the cache results are stored in a file * @filename:		file that stores the results * @bm_pid:		child pid that runs benchmark * @llc_value:		perf miss value / *			llc occupancy value reported by resctrl FS * * Return:		0 on success. non-zero on failure. */static int print_results_cache(char *filename, int bm_pid,			       unsigned long llc_value){	FILE *fp; 	if (strcmp(filename, "stdio") == 0 || strcmp(filename, "stderr") == 0) {		printf("Pid: %d \t LLC_value: %lu\n", bm_pid,		       llc_value);	} else {		fp = fopen(filename, "a");		if (!fp) {			perror("Cannot open results file"); 			return errno;		}		fprintf(fp, "Pid: %d \t llc_value: %lu\n", bm_pid, llc_value);		fclose(fp);	} 	return 0;} int measure_cache_vals(struct resctrl_val_param *param, int bm_pid){	unsigned long llc_perf_miss = 0, llc_occu_resc = 0, llc_value = 0;	int ret; 	/*	 * Measure cache miss from perf.	 */	if (!strncmp(param->resctrl_val, CAT_STR, sizeof(CAT_STR))) {		ret = get_llc_perf(&llc_perf_miss);		if (ret < 0)			return ret;		llc_value = llc_perf_miss;	} 	/*	 * Measure llc occupancy from resctrl.	 */	if (!strncmp(param->resctrl_val, CMT_STR, sizeof(CMT_STR))) {		ret = get_llc_occu_resctrl(&llc_occu_resc);		if (ret < 0)			return ret;		llc_value = llc_occu_resc;	}	ret = print_results_cache(param->filename, bm_pid, llc_value);	if (ret)		return ret; 	return 0;} /* * cache_val:		execute benchmark and measure LLC occupancy resctrl * and perf cache miss for the benchmark * @param:		parameters passed to cache_val() * @span:		buffer size for the benchmark * * Return:		0 on success. non-zero on failure. */int cat_val(struct resctrl_val_param *param, size_t span){	int 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; 	initialize_llc_perf(); 	/* Test runs until the callback setup() tells the test to stop. */	while (1) {		ret = param->setup(param);		if (ret == END_OF_TESTS) {			ret = 0;			break;		}		if (ret < 0)			break;		ret = reset_enable_llc_perf(bm_pid, param->cpu_no);		if (ret)			break; 		if (run_fill_buf(span, memflush, operation, true)) {			fprintf(stderr, "Error-running fill buffer\n");			ret = -1;			goto pe_close;		} 		sleep(1);		ret = measure_cache_vals(param, bm_pid);		if (ret)			goto pe_close;	} 	return ret; pe_close:	close(fd_lm);	return ret;} /* * show_cache_info:	show cache test result information * @sum_llc_val:	sum of LLC cache result data * @no_of_bits:		number of bits * @cache_span:		cache span in bytes for CMT or in lines for CAT * @max_diff:		max difference * @max_diff_percent:	max difference percentage * @num_of_runs:	number of runs * @platform:		show test information on this platform * @cmt:		CMT test or CAT test * * Return:		0 on success. non-zero on failure. */int show_cache_info(unsigned long sum_llc_val, int no_of_bits,		    size_t cache_span, unsigned long max_diff,		    unsigned long max_diff_percent, unsigned long num_of_runs,		    bool platform, bool cmt){	unsigned long avg_llc_val = 0;	float diff_percent;	long avg_diff = 0;	int ret; 	avg_llc_val = sum_llc_val / num_of_runs;	avg_diff = (long)abs(cache_span - avg_llc_val);	diff_percent = ((float)cache_span - avg_llc_val) / cache_span * 100; 	ret = platform && abs((int)diff_percent) > max_diff_percent &&	      (cmt ? (abs(avg_diff) > max_diff) : true); 	ksft_print_msg("%s Check cache miss rate within %lu%%\n",		       ret ? "Fail:" : "Pass:", max_diff_percent); 	ksft_print_msg("Percent diff=%d\n", abs((int)diff_percent));	ksft_print_msg("Number of bits: %d\n", no_of_bits);	ksft_print_msg("Average LLC val: %lu\n", avg_llc_val);	ksft_print_msg("Cache span (%s): %zu\n", cmt ? "bytes" : "lines",		       cache_span); 	return ret;}