1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Cache Allocation Technology (CAT) 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_NAME1 "result_cat1"
15 #define RESULT_FILE_NAME2 "result_cat2"
16 #define NUM_OF_RUNS 5
17 #define MAX_DIFF_PERCENT 4
18 #define MAX_DIFF 1000000
19
20 /*
21 * Change schemata. Write schemata to specified
22 * con_mon grp, mon_grp in resctrl FS.
23 * Run 5 times in order to get average values.
24 */
cat_setup(struct resctrl_val_param * p)25 static int cat_setup(struct resctrl_val_param *p)
26 {
27 char schemata[64];
28 int ret = 0;
29
30 /* Run NUM_OF_RUNS times */
31 if (p->num_of_runs >= NUM_OF_RUNS)
32 return END_OF_TESTS;
33
34 if (p->num_of_runs == 0) {
35 sprintf(schemata, "%lx", p->mask);
36 ret = write_schemata(p->ctrlgrp, schemata, p->cpu_no,
37 p->resctrl_val);
38 }
39 p->num_of_runs++;
40
41 return ret;
42 }
43
check_results(struct resctrl_val_param * param,size_t span)44 static int check_results(struct resctrl_val_param *param, size_t span)
45 {
46 char *token_array[8], temp[512];
47 unsigned long sum_llc_perf_miss = 0;
48 int runs = 0, no_of_bits = 0;
49 FILE *fp;
50
51 ksft_print_msg("Checking for pass/fail\n");
52 fp = fopen(param->filename, "r");
53 if (!fp) {
54 perror("# Cannot open file");
55
56 return errno;
57 }
58
59 while (fgets(temp, sizeof(temp), fp)) {
60 char *token = strtok(temp, ":\t");
61 int fields = 0;
62
63 while (token) {
64 token_array[fields++] = token;
65 token = strtok(NULL, ":\t");
66 }
67 /*
68 * Discard the first value which is inaccurate due to monitoring
69 * setup transition phase.
70 */
71 if (runs > 0)
72 sum_llc_perf_miss += strtoul(token_array[3], NULL, 0);
73 runs++;
74 }
75
76 fclose(fp);
77 no_of_bits = count_bits(param->mask);
78
79 return show_cache_info(sum_llc_perf_miss, no_of_bits, span / 64,
80 MAX_DIFF, MAX_DIFF_PERCENT, runs - 1,
81 get_vendor() == ARCH_INTEL, false);
82 }
83
cat_test_cleanup(void)84 void cat_test_cleanup(void)
85 {
86 remove(RESULT_FILE_NAME1);
87 remove(RESULT_FILE_NAME2);
88 }
89
cat_perf_miss_val(int cpu_no,int n,char * cache_type)90 int cat_perf_miss_val(int cpu_no, int n, char *cache_type)
91 {
92 unsigned long l_mask, l_mask_1;
93 int ret, pipefd[2], sibling_cpu_no;
94 unsigned long cache_size = 0;
95 unsigned long long_mask;
96 char cbm_mask[256];
97 int count_of_bits;
98 char pipe_message;
99 size_t span;
100
101 /* Get default cbm mask for L3/L2 cache */
102 ret = get_cbm_mask(cache_type, cbm_mask);
103 if (ret)
104 return ret;
105
106 long_mask = strtoul(cbm_mask, NULL, 16);
107
108 /* Get L3/L2 cache size */
109 ret = get_cache_size(cpu_no, cache_type, &cache_size);
110 if (ret)
111 return ret;
112 ksft_print_msg("Cache size :%lu\n", cache_size);
113
114 /* Get max number of bits from default-cabm mask */
115 count_of_bits = count_bits(long_mask);
116
117 if (!n)
118 n = count_of_bits / 2;
119
120 if (n > count_of_bits - 1) {
121 ksft_print_msg("Invalid input value for no_of_bits n!\n");
122 ksft_print_msg("Please enter value in range 1 to %d\n",
123 count_of_bits - 1);
124 return -1;
125 }
126
127 /* Get core id from same socket for running another thread */
128 sibling_cpu_no = get_core_sibling(cpu_no);
129 if (sibling_cpu_no < 0)
130 return -1;
131
132 struct resctrl_val_param param = {
133 .resctrl_val = CAT_STR,
134 .cpu_no = cpu_no,
135 .setup = cat_setup,
136 };
137
138 l_mask = long_mask >> n;
139 l_mask_1 = ~l_mask & long_mask;
140
141 /* Set param values for parent thread which will be allocated bitmask
142 * with (max_bits - n) bits
143 */
144 span = cache_size * (count_of_bits - n) / count_of_bits;
145 strcpy(param.ctrlgrp, "c2");
146 strcpy(param.mongrp, "m2");
147 strcpy(param.filename, RESULT_FILE_NAME2);
148 param.mask = l_mask;
149 param.num_of_runs = 0;
150
151 if (pipe(pipefd)) {
152 perror("# Unable to create pipe");
153 return errno;
154 }
155
156 fflush(stdout);
157 bm_pid = fork();
158
159 /* Set param values for child thread which will be allocated bitmask
160 * with n bits
161 */
162 if (bm_pid == 0) {
163 param.mask = l_mask_1;
164 strcpy(param.ctrlgrp, "c1");
165 strcpy(param.mongrp, "m1");
166 span = cache_size * n / count_of_bits;
167 strcpy(param.filename, RESULT_FILE_NAME1);
168 param.num_of_runs = 0;
169 param.cpu_no = sibling_cpu_no;
170 }
171
172 remove(param.filename);
173
174 ret = cat_val(¶m, span);
175 if (ret == 0)
176 ret = check_results(¶m, span);
177
178 if (bm_pid == 0) {
179 /* Tell parent that child is ready */
180 close(pipefd[0]);
181 pipe_message = 1;
182 if (write(pipefd[1], &pipe_message, sizeof(pipe_message)) <
183 sizeof(pipe_message))
184 /*
185 * Just print the error message.
186 * Let while(1) run and wait for itself to be killed.
187 */
188 perror("# failed signaling parent process");
189
190 close(pipefd[1]);
191 while (1)
192 ;
193 } else {
194 /* Parent waits for child to be ready. */
195 close(pipefd[1]);
196 pipe_message = 0;
197 while (pipe_message != 1) {
198 if (read(pipefd[0], &pipe_message,
199 sizeof(pipe_message)) < sizeof(pipe_message)) {
200 perror("# failed reading from child process");
201 break;
202 }
203 }
204 close(pipefd[0]);
205 kill(bm_pid, SIGKILL);
206 }
207
208 cat_test_cleanup();
209
210 return ret;
211 }
212