tools/testing/selftests/resctrl/mbm_test.c

   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                300
  15 #define NUM_OF_RUNS             5
  16
  17 static void
  18 show_bw_info(unsigned long *bw_imc, unsigned long *bw_resc, int span)
  19 {
  20         unsigned long avg_bw_imc = 0, avg_bw_resc = 0;
  21         unsigned long sum_bw_imc = 0, sum_bw_resc = 0;
  22         long avg_diff = 0;
  23         int runs;
  24
  25         /*
  26          * Discard the first value which is inaccurate due to monitoring setup
  27          * transition phase.
  28          */
  29         for (runs = 1; runs < NUM_OF_RUNS ; runs++) {
  30                 sum_bw_imc += bw_imc[runs];
  31                 sum_bw_resc += bw_resc[runs];
  32         }
  33
  34         avg_bw_imc = sum_bw_imc / 4;
  35         avg_bw_resc = sum_bw_resc / 4;
  36         avg_diff = avg_bw_resc - avg_bw_imc;
  37
  38         printf("%sok MBM: diff within %d%%\n",
  39                labs(avg_diff) > MAX_DIFF ? "not " : "", MAX_DIFF);
  40         tests_run++;
  41         printf("# avg_diff: %lu\n", labs(avg_diff));
  42         printf("# Span (MB): %d\n", span);
  43         printf("# avg_bw_imc: %lu\n", avg_bw_imc);
  44         printf("# avg_bw_resc: %lu\n", avg_bw_resc);
  45 }
  46
  47 static int check_results(int 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;
  53         FILE *fp;
  54
  55         printf("# Checking for pass/fail\n");
  56
  57         fp = fopen(output, "r");
  58         if (!fp) {
  59                 perror(output);
  60
  61                 return errno;
  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         show_bw_info(bw_imc, bw_resc, span);
  80
  81         fclose(fp);
  82
  83         return 0;
  84 }
  85
  86 static int mbm_setup(int num, ...)
  87 {
  88         struct resctrl_val_param *p;
  89         static int num_of_runs;
  90         va_list param;
  91         int ret = 0;
  92
  93         /* Run NUM_OF_RUNS times */
  94         if (num_of_runs++ >= NUM_OF_RUNS)
  95                 return -1;
  96
  97         va_start(param, num);
  98         p = va_arg(param, struct resctrl_val_param *);
  99         va_end(param);
 100
 101         /* Set up shemata with 100% allocation on the first run. */
 102         if (num_of_runs == 0)
 103                 ret = write_schemata(p->ctrlgrp, "100", p->cpu_no,
 104                                      p->resctrl_val);
 105
 106         return ret;
 107 }
 108
 109 void mbm_test_cleanup(void)
 110 {
 111         remove(RESULT_FILE_NAME);
 112 }
 113
 114 int mbm_bw_change(int span, int cpu_no, char *bw_report, char **benchmark_cmd)
 115 {
 116         struct resctrl_val_param param = {
 117                 .resctrl_val    = "mbm",
 118                 .ctrlgrp        = "c1",
 119                 .mongrp         = "m1",
 120                 .span           = span,
 121                 .cpu_no         = cpu_no,
 122                 .mum_resctrlfs  = 1,
 123                 .filename       = RESULT_FILE_NAME,
 124                 .bw_report      =  bw_report,
 125                 .setup          = mbm_setup
 126         };
 127         int ret;
 128
 129         remove(RESULT_FILE_NAME);
 130
 131         if (!validate_resctrl_feature_request("mbm"))
 132                 return -1;
 133
 134         ret = resctrl_val(benchmark_cmd, &param);
 135         if (ret)
 136                 return ret;
 137
 138         ret = check_results(span);
 139         if (ret)
 140                 return ret;
 141
 142         mbm_test_cleanup();
 143
 144         return 0;
 145 }