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 int
  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, ret;
  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         ret = labs(avg_diff) > MAX_DIFF;
  39         ksft_print_msg("%s MBM: diff within %d%%\n",
  40                        ret ? "Fail:" : "Pass:", MAX_DIFF);
  41         ksft_print_msg("avg_diff: %lu\n", labs(avg_diff));
  42         ksft_print_msg("Span (MB): %d\n", span);
  43         ksft_print_msg("avg_bw_imc: %lu\n", avg_bw_imc);
  44         ksft_print_msg("avg_bw_resc: %lu\n", avg_bw_resc);
  45
  46         return ret;
  47 }
  48
  49 static int check_results(int span)
  50 {
  51         unsigned long bw_imc[NUM_OF_RUNS], bw_resc[NUM_OF_RUNS];
  52         char temp[1024], *token_array[8];
  53         char output[] = RESULT_FILE_NAME;
  54         int runs, ret;
  55         FILE *fp;
  56
  57         ksft_print_msg("Checking for pass/fail\n");
  58
  59         fp = fopen(output, "r");
  60         if (!fp) {
  61                 perror(output);
  62
  63                 return errno;
  64         }
  65
  66         runs = 0;
  67         while (fgets(temp, sizeof(temp), fp)) {
  68                 char *token = strtok(temp, ":\t");
  69                 int i = 0;
  70
  71                 while (token) {
  72                         token_array[i++] = token;
  73                         token = strtok(NULL, ":\t");
  74                 }
  75
  76                 bw_resc[runs] = strtoul(token_array[5], NULL, 0);
  77                 bw_imc[runs] = strtoul(token_array[3], NULL, 0);
  78                 runs++;
  79         }
  80
  81         ret = show_bw_info(bw_imc, bw_resc, span);
  82
  83         fclose(fp);
  84
  85         return ret;
  86 }
  87
  88 static int mbm_setup(int num, ...)
  89 {
  90         struct resctrl_val_param *p;
  91         static int num_of_runs;
  92         va_list param;
  93         int ret = 0;
  94
  95         /* Run NUM_OF_RUNS times */
  96         if (num_of_runs++ >= NUM_OF_RUNS)
  97                 return -1;
  98
  99         va_start(param, num);
 100         p = va_arg(param, struct resctrl_val_param *);
 101         va_end(param);
 102
 103         /* Set up shemata with 100% allocation on the first run. */
 104         if (num_of_runs == 0)
 105                 ret = write_schemata(p->ctrlgrp, "100", p->cpu_no,
 106                                      p->resctrl_val);
 107
 108         return ret;
 109 }
 110
 111 void mbm_test_cleanup(void)
 112 {
 113         remove(RESULT_FILE_NAME);
 114 }
 115
 116 int mbm_bw_change(int span, int cpu_no, char *bw_report, char **benchmark_cmd)
 117 {
 118         struct resctrl_val_param param = {
 119                 .resctrl_val    = MBM_STR,
 120                 .ctrlgrp        = "c1",
 121                 .mongrp         = "m1",
 122                 .span           = span,
 123                 .cpu_no         = cpu_no,
 124                 .mum_resctrlfs  = 1,
 125                 .filename       = RESULT_FILE_NAME,
 126                 .bw_report      =  bw_report,
 127                 .setup          = mbm_setup
 128         };
 129         int ret;
 130
 131         remove(RESULT_FILE_NAME);
 132
 133         if (!validate_resctrl_feature_request("mbm"))
 134                 return -1;
 135
 136         ret = resctrl_val(benchmark_cmd, &param);
 137         if (ret)
 138                 return ret;
 139
 140         ret = check_results(span);
 141         if (ret)
 142                 return ret;
 143
 144         mbm_test_cleanup();
 145
 146         return 0;
 147 }