1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Cache Monitoring Technology (CMT) test
  4 *
  5 * Copyright (C) 2018 Intel Corporation
  6 *
  7 * Authors:
  8 *    Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>,
  9 *    Fenghua Yu <fenghua.yu@intel.com>
 10 */
 11#include "resctrl.h"
 12#include <unistd.h>
 13
 14#define RESULT_FILE_NAME	"result_cmt"
 15#define NUM_OF_RUNS		5
 16#define MAX_DIFF		2000000
 17#define MAX_DIFF_PERCENT	15
 18
 19static int cmt_setup(const struct resctrl_test *test,
 20		     const struct user_params *uparams,
 21		     struct resctrl_val_param *p)
 22{
 23	/* Run NUM_OF_RUNS times */
 24	if (p->num_of_runs >= NUM_OF_RUNS)
 25		return END_OF_TESTS;
 26
 27	p->num_of_runs++;
 28
 29	return 0;
 30}
 31
 32static int show_results_info(unsigned long sum_llc_val, int no_of_bits,
 33			     unsigned long cache_span, unsigned long max_diff,
 34			     unsigned long max_diff_percent, unsigned long num_of_runs,
 35			     bool platform)
 36{
 37	unsigned long avg_llc_val = 0;
 38	float diff_percent;
 39	long avg_diff = 0;
 40	int ret;
 41
 42	avg_llc_val = sum_llc_val / num_of_runs;
 43	avg_diff = (long)abs(cache_span - avg_llc_val);
 44	diff_percent = ((float)cache_span - avg_llc_val) / cache_span * 100;
 45
 46	ret = platform && abs((int)diff_percent) > max_diff_percent &&
 47	      abs(avg_diff) > max_diff;
 48
 49	ksft_print_msg("%s Check cache miss rate within %lu%%\n",
 50		       ret ? "Fail:" : "Pass:", max_diff_percent);
 51
 52	ksft_print_msg("Percent diff=%d\n", abs((int)diff_percent));
 53
 54	show_cache_info(no_of_bits, avg_llc_val, cache_span, false);
 55
 56	return ret;
 57}
 58
 59static int check_results(struct resctrl_val_param *param, size_t span, int no_of_bits)
 60{
 61	char *token_array[8], temp[512];
 62	unsigned long sum_llc_occu_resc = 0;
 63	int runs = 0;
 64	FILE *fp;
 65
 66	ksft_print_msg("Checking for pass/fail\n");
 67	fp = fopen(param->filename, "r");
 68	if (!fp) {
 69		ksft_perror("Error in opening file");
 70
 71		return -1;
 72	}
 73
 74	while (fgets(temp, sizeof(temp), fp)) {
 75		char *token = strtok(temp, ":\t");
 76		int fields = 0;
 77
 78		while (token) {
 79			token_array[fields++] = token;
 80			token = strtok(NULL, ":\t");
 81		}
 82
 83		/* Field 3 is llc occ resc value */
 84		if (runs > 0)
 85			sum_llc_occu_resc += strtoul(token_array[3], NULL, 0);
 86		runs++;
 87	}
 88	fclose(fp);
 89
 90	return show_results_info(sum_llc_occu_resc, no_of_bits, span,
 91				 MAX_DIFF, MAX_DIFF_PERCENT, runs - 1, true);
 92}
 93
 94void cmt_test_cleanup(void)
 95{
 96	remove(RESULT_FILE_NAME);
 97}
 98
 99static int cmt_run_test(const struct resctrl_test *test, const struct user_params *uparams)
100{
101	const char * const *cmd = uparams->benchmark_cmd;
102	const char *new_cmd[BENCHMARK_ARGS];
103	unsigned long cache_total_size = 0;
104	int n = uparams->bits ? : 5;
105	unsigned long long_mask;
106	char *span_str = NULL;
107	int count_of_bits;
108	size_t span;
109	int ret, i;
110
111	ret = get_full_cbm("L3", &long_mask);
112	if (ret)
113		return ret;
114
115	ret = get_cache_size(uparams->cpu, "L3", &cache_total_size);
116	if (ret)
117		return ret;
118	ksft_print_msg("Cache size :%lu\n", cache_total_size);
119
120	count_of_bits = count_bits(long_mask);
121
122	if (n < 1 || n > count_of_bits) {
123		ksft_print_msg("Invalid input value for numbr_of_bits n!\n");
124		ksft_print_msg("Please enter value in range 1 to %d\n", count_of_bits);
125		return -1;
126	}
127
128	struct resctrl_val_param param = {
129		.resctrl_val	= CMT_STR,
130		.ctrlgrp	= "c1",
131		.mongrp		= "m1",
132		.filename	= RESULT_FILE_NAME,
133		.mask		= ~(long_mask << n) & long_mask,
134		.num_of_runs	= 0,
135		.setup		= cmt_setup,
136	};
137
138	span = cache_portion_size(cache_total_size, param.mask, long_mask);
139
140	if (strcmp(cmd[0], "fill_buf") == 0) {
141		/* Duplicate the command to be able to replace span in it */
142		for (i = 0; uparams->benchmark_cmd[i]; i++)
143			new_cmd[i] = uparams->benchmark_cmd[i];
144		new_cmd[i] = NULL;
145
146		ret = asprintf(&span_str, "%zu", span);
147		if (ret < 0)
148			return -1;
149		new_cmd[1] = span_str;
150		cmd = new_cmd;
151	}
152
153	remove(RESULT_FILE_NAME);
154
155	ret = resctrl_val(test, uparams, cmd, &param);
156	if (ret)
157		goto out;
158
159	ret = check_results(&param, span, n);
160	if (ret && (get_vendor() == ARCH_INTEL))
161		ksft_print_msg("Intel CMT may be inaccurate when Sub-NUMA Clustering is enabled. Check BIOS configuration.\n");
162
163out:
164	cmt_test_cleanup();
165	free(span_str);
166
167	return ret;
168}
169
170static bool cmt_feature_check(const struct resctrl_test *test)
171{
172	return test_resource_feature_check(test) &&
173	       resctrl_mon_feature_exists("L3_MON", "llc_occupancy");
174}
175
176struct resctrl_test cmt_test = {
177	.name = "CMT",
178	.resource = "L3",
179	.feature_check = cmt_feature_check,
180	.run_test = cmt_run_test,
181};