1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Memory Bandwidth Monitoring (MBM) 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 13 #define RESULT_FILE_NAME "result_mbm" 14 #define MAX_DIFF_PERCENT 8 15 #define NUM_OF_RUNS 5 16 17 static int 18 show_bw_info(unsigned long *bw_imc, unsigned long *bw_resc, size_t span) 19 { 20 unsigned long sum_bw_imc = 0, sum_bw_resc = 0; 21 long avg_bw_imc = 0, avg_bw_resc = 0; 22 int runs, ret, avg_diff_per; 23 float avg_diff = 0; 24 25 for (runs = 0; runs < NUM_OF_RUNS; runs++) { 26 sum_bw_imc += bw_imc[runs]; 27 sum_bw_resc += bw_resc[runs]; 28 } 29 30 avg_bw_imc = sum_bw_imc / NUM_OF_RUNS; 31 avg_bw_resc = sum_bw_resc / NUM_OF_RUNS; 32 avg_diff = (float)labs(avg_bw_resc - avg_bw_imc) / avg_bw_imc; 33 avg_diff_per = (int)(avg_diff * 100); 34 35 ret = avg_diff_per > MAX_DIFF_PERCENT; 36 ksft_print_msg("%s Check MBM diff within %d%%\n", 37 ret ? "Fail:" : "Pass:", MAX_DIFF_PERCENT); 38 ksft_print_msg("avg_diff_per: %d%%\n", avg_diff_per); 39 if (span) 40 ksft_print_msg("Span (MB): %zu\n", span / MB); 41 ksft_print_msg("avg_bw_imc: %lu\n", avg_bw_imc); 42 ksft_print_msg("avg_bw_resc: %lu\n", avg_bw_resc); 43 44 return ret; 45 } 46 47 static int check_results(size_t span) 48 { 49 unsigned long bw_imc[NUM_OF_RUNS], bw_resc[NUM_OF_RUNS]; 50 char temp[1024], *token_array[8]; 51 char output[] = RESULT_FILE_NAME; 52 int runs, ret; 53 FILE *fp; 54 55 ksft_print_msg("Checking for pass/fail\n"); 56 57 fp = fopen(output, "r"); 58 if (!fp) { 59 ksft_perror(output); 60 61 return -1; 62 } 63 64 runs = 0; 65 while (fgets(temp, sizeof(temp), fp)) { 66 char *token = strtok(temp, ":\t"); 67 int i = 0; 68 69 while (token) { 70 token_array[i++] = token; 71 token = strtok(NULL, ":\t"); 72 } 73 74 bw_resc[runs] = strtoul(token_array[5], NULL, 0); 75 bw_imc[runs] = strtoul(token_array[3], NULL, 0); 76 runs++; 77 } 78 79 ret = show_bw_info(bw_imc, bw_resc, span); 80 81 fclose(fp); 82 83 return ret; 84 } 85 86 static int mbm_init(const struct resctrl_val_param *param, int domain_id) 87 { 88 int ret; 89 90 ret = initialize_read_mem_bw_imc(); 91 if (ret) 92 return ret; 93 94 initialize_mem_bw_resctrl(param, domain_id); 95 96 return 0; 97 } 98 99 static int mbm_setup(const struct resctrl_test *test, 100 const struct user_params *uparams, 101 struct resctrl_val_param *p) 102 { 103 int ret = 0; 104 105 /* Run NUM_OF_RUNS times */ 106 if (p->num_of_runs >= NUM_OF_RUNS) 107 return END_OF_TESTS; 108 109 /* Set up shemata with 100% allocation on the first run. */ 110 if (p->num_of_runs == 0 && resctrl_resource_exists("MB")) 111 ret = write_schemata(p->ctrlgrp, "100", uparams->cpu, test->resource); 112 113 p->num_of_runs++; 114 115 return ret; 116 } 117 118 static int mbm_measure(const struct user_params *uparams, 119 struct resctrl_val_param *param, pid_t bm_pid) 120 { 121 return measure_read_mem_bw(uparams, param, bm_pid); 122 } 123 124 static void mbm_test_cleanup(void) 125 { 126 remove(RESULT_FILE_NAME); 127 } 128 129 static int mbm_run_test(const struct resctrl_test *test, const struct user_params *uparams) 130 { 131 struct resctrl_val_param param = { 132 .ctrlgrp = "c1", 133 .filename = RESULT_FILE_NAME, 134 .init = mbm_init, 135 .setup = mbm_setup, 136 .measure = mbm_measure, 137 }; 138 struct fill_buf_param fill_buf = {}; 139 int ret; 140 141 remove(RESULT_FILE_NAME); 142 143 if (uparams->fill_buf) { 144 fill_buf.buf_size = uparams->fill_buf->buf_size; 145 fill_buf.memflush = uparams->fill_buf->memflush; 146 param.fill_buf = &fill_buf; 147 } else if (!uparams->benchmark_cmd[0]) { 148 ssize_t buf_size; 149 150 buf_size = get_fill_buf_size(uparams->cpu, "L3"); 151 if (buf_size < 0) 152 return buf_size; 153 fill_buf.buf_size = buf_size; 154 fill_buf.memflush = true; 155 param.fill_buf = &fill_buf; 156 } 157 158 ret = resctrl_val(test, uparams, ¶m); 159 if (ret) 160 return ret; 161 162 ret = check_results(param.fill_buf ? param.fill_buf->buf_size : 0); 163 if (ret && (get_vendor() == ARCH_INTEL)) 164 ksft_print_msg("Intel MBM may be inaccurate when Sub-NUMA Clustering is enabled. Check BIOS configuration.\n"); 165 166 return ret; 167 } 168 169 static bool mbm_feature_check(const struct resctrl_test *test) 170 { 171 return resctrl_mon_feature_exists("L3_MON", "mbm_total_bytes") && 172 resctrl_mon_feature_exists("L3_MON", "mbm_local_bytes"); 173 } 174 175 struct resctrl_test mbm_test = { 176 .name = "MBM", 177 .resource = "MB", 178 .vendor_specific = ARCH_INTEL, 179 .feature_check = mbm_feature_check, 180 .run_test = mbm_run_test, 181 .cleanup = mbm_test_cleanup, 182 }; 183