1 // SPDX-License-Identifier: GPL-2.0
3 * Cache Allocation Technology (CAT) test
5 * Copyright (C) 2018 Intel Corporation
8 * Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>,
9 * Fenghua Yu <fenghua.yu@intel.com>
14 #define RESULT_FILE_NAME1 "result_cat1"
15 #define RESULT_FILE_NAME2 "result_cat2"
17 #define MAX_DIFF_PERCENT 4
18 #define MAX_DIFF 1000000
22 unsigned long long_mask;
23 unsigned long cache_size;
26 * Change schemata. Write schemata to specified
27 * con_mon grp, mon_grp in resctrl FS.
28 * Run 5 times in order to get average values.
30 static int cat_setup(int num, ...)
32 struct resctrl_val_param *p;
38 p = va_arg(param, struct resctrl_val_param *);
41 /* Run NUM_OF_RUNS times */
42 if (p->num_of_runs >= NUM_OF_RUNS)
45 if (p->num_of_runs == 0) {
46 sprintf(schemata, "%lx", p->mask);
47 ret = write_schemata(p->ctrlgrp, schemata, p->cpu_no,
55 static void show_cache_info(unsigned long sum_llc_perf_miss, int no_of_bits,
58 unsigned long allocated_cache_lines = span / 64;
59 unsigned long avg_llc_perf_miss = 0;
62 avg_llc_perf_miss = sum_llc_perf_miss / (NUM_OF_RUNS - 1);
63 diff_percent = ((float)allocated_cache_lines - avg_llc_perf_miss) /
64 allocated_cache_lines * 100;
66 printf("%sok CAT: cache miss rate within %d%%\n",
67 !is_amd && abs((int)diff_percent) > MAX_DIFF_PERCENT ?
68 "not " : "", MAX_DIFF_PERCENT);
70 printf("# Percent diff=%d\n", abs((int)diff_percent));
71 printf("# Number of bits: %d\n", no_of_bits);
72 printf("# Avg_llc_perf_miss: %lu\n", avg_llc_perf_miss);
73 printf("# Allocated cache lines: %lu\n", allocated_cache_lines);
76 static int check_results(struct resctrl_val_param *param)
78 char *token_array[8], temp[512];
79 unsigned long sum_llc_perf_miss = 0;
80 int runs = 0, no_of_bits = 0;
83 printf("# Checking for pass/fail\n");
84 fp = fopen(param->filename, "r");
86 perror("# Cannot open file");
91 while (fgets(temp, sizeof(temp), fp)) {
92 char *token = strtok(temp, ":\t");
96 token_array[fields++] = token;
97 token = strtok(NULL, ":\t");
100 * Discard the first value which is inaccurate due to monitoring
101 * setup transition phase.
104 sum_llc_perf_miss += strtoul(token_array[3], NULL, 0);
109 no_of_bits = count_bits(param->mask);
111 show_cache_info(sum_llc_perf_miss, no_of_bits, param->span);
116 void cat_test_cleanup(void)
118 remove(RESULT_FILE_NAME1);
119 remove(RESULT_FILE_NAME2);
122 int cat_perf_miss_val(int cpu_no, int n, char *cache_type)
124 unsigned long l_mask, l_mask_1;
125 int ret, pipefd[2], sibling_cpu_no;
131 ret = remount_resctrlfs(true);
135 if (!validate_resctrl_feature_request("cat"))
138 /* Get default cbm mask for L3/L2 cache */
139 ret = get_cbm_mask(cache_type);
143 long_mask = strtoul(cbm_mask, NULL, 16);
145 /* Get L3/L2 cache size */
146 ret = get_cache_size(cpu_no, cache_type, &cache_size);
149 printf("cache size :%lu\n", cache_size);
151 /* Get max number of bits from default-cabm mask */
152 count_of_bits = count_bits(long_mask);
154 if (n < 1 || n > count_of_bits - 1) {
155 printf("Invalid input value for no_of_bits n!\n");
156 printf("Please Enter value in range 1 to %d\n",
161 /* Get core id from same socket for running another thread */
162 sibling_cpu_no = get_core_sibling(cpu_no);
163 if (sibling_cpu_no < 0)
166 struct resctrl_val_param param = {
167 .resctrl_val = "cat",
173 l_mask = long_mask >> n;
174 l_mask_1 = ~l_mask & long_mask;
176 /* Set param values for parent thread which will be allocated bitmask
177 * with (max_bits - n) bits
179 param.span = cache_size * (count_of_bits - n) / count_of_bits;
180 strcpy(param.ctrlgrp, "c2");
181 strcpy(param.mongrp, "m2");
182 strcpy(param.filename, RESULT_FILE_NAME2);
184 param.num_of_runs = 0;
187 perror("# Unable to create pipe");
193 /* Set param values for child thread which will be allocated bitmask
197 param.mask = l_mask_1;
198 strcpy(param.ctrlgrp, "c1");
199 strcpy(param.mongrp, "m1");
200 param.span = cache_size * n / count_of_bits;
201 strcpy(param.filename, RESULT_FILE_NAME1);
202 param.num_of_runs = 0;
203 param.cpu_no = sibling_cpu_no;
206 remove(param.filename);
208 ret = cat_val(¶m);
212 ret = check_results(¶m);
217 /* Tell parent that child is ready */
220 if (write(pipefd[1], &pipe_message, sizeof(pipe_message)) <
221 sizeof(pipe_message)) {
223 perror("# failed signaling parent process");
231 /* Parent waits for child to be ready. */
234 while (pipe_message != 1) {
235 if (read(pipefd[0], &pipe_message,
236 sizeof(pipe_message)) < sizeof(pipe_message)) {
237 perror("# failed reading from child process");
242 kill(bm_pid, SIGKILL);