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
 19#define CON_MON_LCC_OCCUP_PATH		\
 20	"%s/%s/mon_data/mon_L3_%02d/llc_occupancy"
 21
 22static int cmt_init(const struct resctrl_val_param *param, int domain_id)
 23{
 24	sprintf(llc_occup_path, CON_MON_LCC_OCCUP_PATH, RESCTRL_PATH,
 25		param->ctrlgrp, domain_id);
 26
 27	return 0;
 28}
 29
 30static int cmt_setup(const struct resctrl_test *test,
 31		     const struct user_params *uparams,
 32		     struct resctrl_val_param *p)
 33{
 34	/* Run NUM_OF_RUNS times */
 35	if (p->num_of_runs >= NUM_OF_RUNS)
 36		return END_OF_TESTS;
 37
 38	p->num_of_runs++;
 39
 40	return 0;
 41}
 42
 43static int cmt_measure(const struct user_params *uparams,
 44		       struct resctrl_val_param *param, pid_t bm_pid)
 45{
 46	sleep(1);
 47	return measure_llc_resctrl(param->filename, bm_pid);
 48}
 49
 50static int show_results_info(unsigned long sum_llc_val, int no_of_bits,
 51			     unsigned long cache_span, unsigned long max_diff,
 52			     unsigned long max_diff_percent, unsigned long num_of_runs,
 53			     bool platform)
 54{
 55	unsigned long avg_llc_val = 0;
 56	float diff_percent;
 57	long avg_diff = 0;
 58	int ret;
 59
 60	avg_llc_val = sum_llc_val / num_of_runs;
 61	avg_diff = (long)(cache_span - avg_llc_val);
 62	diff_percent = ((float)cache_span - avg_llc_val) / cache_span * 100;
 63
 64	ret = platform && abs((int)diff_percent) > max_diff_percent &&
 65	      labs(avg_diff) > max_diff;
 66
 67	ksft_print_msg("%s Check cache miss rate within %lu%%\n",
 68		       ret ? "Fail:" : "Pass:", max_diff_percent);
 69
 70	ksft_print_msg("Percent diff=%d\n", abs((int)diff_percent));
 71
 72	show_cache_info(no_of_bits, avg_llc_val, cache_span, false);
 73
 74	return ret;
 75}
 76
 77static int check_results(struct resctrl_val_param *param, size_t span, int no_of_bits)
 78{
 79	char *token_array[8], temp[512];
 80	unsigned long sum_llc_occu_resc = 0;
 81	int runs = 0;
 82	FILE *fp;
 83
 84	ksft_print_msg("Checking for pass/fail\n");
 85	fp = fopen(param->filename, "r");
 86	if (!fp) {
 87		ksft_perror("Error in opening file");
 88
 89		return -1;
 90	}
 91
 92	while (fgets(temp, sizeof(temp), fp)) {
 93		char *token = strtok(temp, ":\t");
 94		int fields = 0;
 95
 96		while (token) {
 97			token_array[fields++] = token;
 98			token = strtok(NULL, ":\t");
 99		}
100
101		/* Field 3 is llc occ resc value */
102		sum_llc_occu_resc += strtoul(token_array[3], NULL, 0);
103		runs++;
104	}
105	fclose(fp);
106
107	return show_results_info(sum_llc_occu_resc, no_of_bits, span,
108				 MAX_DIFF, MAX_DIFF_PERCENT, runs, true);
109}
110
111static void cmt_test_cleanup(void)
112{
113	remove(RESULT_FILE_NAME);
114}
115
116static int cmt_run_test(const struct resctrl_test *test, const struct user_params *uparams)
117{
118	struct fill_buf_param fill_buf = {};
119	unsigned long cache_total_size = 0;
120	int n = uparams->bits ? : 5;
121	unsigned long long_mask;
122	int count_of_bits;
123	size_t span;
124	int ret;
125
126	ret = get_full_cbm("L3", &long_mask);
127	if (ret)
128		return ret;
129
130	ret = get_cache_size(uparams->cpu, "L3", &cache_total_size);
131	if (ret)
132		return ret;
133	ksft_print_msg("Cache size :%lu\n", cache_total_size);
134
135	count_of_bits = count_bits(long_mask);
136
137	if (n < 1 || n > count_of_bits) {
138		ksft_print_msg("Invalid input value for numbr_of_bits n!\n");
139		ksft_print_msg("Please enter value in range 1 to %d\n", count_of_bits);
140		return -1;
141	}
142
143	struct resctrl_val_param param = {
144		.ctrlgrp	= "c1",
145		.filename	= RESULT_FILE_NAME,
146		.mask		= ~(long_mask << n) & long_mask,
147		.num_of_runs	= 0,
148		.init		= cmt_init,
149		.setup		= cmt_setup,
150		.measure	= cmt_measure,
151	};
152
153	span = cache_portion_size(cache_total_size, param.mask, long_mask);
154
155	if (uparams->fill_buf) {
156		fill_buf.buf_size = span;
157		fill_buf.memflush = uparams->fill_buf->memflush;
158		param.fill_buf = &fill_buf;
159	} else if (!uparams->benchmark_cmd[0]) {
160		fill_buf.buf_size = span;
161		fill_buf.memflush = true;
162		param.fill_buf = &fill_buf;
163	}
164
165	remove(RESULT_FILE_NAME);
166
167	ret = resctrl_val(test, uparams, &param);
168	if (ret)
169		return ret;
170
171	ret = check_results(&param, span, n);
172	if (ret && (get_vendor() == ARCH_INTEL))
173		ksft_print_msg("Intel CMT may be inaccurate when Sub-NUMA Clustering is enabled. Check BIOS configuration.\n");
174
175	return ret;
176}
177
178static bool cmt_feature_check(const struct resctrl_test *test)
179{
180	return test_resource_feature_check(test) &&
181	       resctrl_mon_feature_exists("L3_MON", "llc_occupancy");
182}
183
184struct resctrl_test cmt_test = {
185	.name = "CMT",
186	.resource = "L3",
187	.feature_check = cmt_feature_check,
188	.run_test = cmt_run_test,
189	.cleanup = cmt_test_cleanup,
190};