tools/testing/selftests/resctrl/mba_test.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Memory Bandwidth Allocation (MBA) 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_mba"
  14 #define NUM_OF_RUNS             5
  15 #define MAX_DIFF_PERCENT        8
  16 #define ALLOCATION_MAX          100
  17 #define ALLOCATION_MIN          10
  18 #define ALLOCATION_STEP         10
  19
  20 /*
  21  * Change schemata percentage from 100 to 10%. Write schemata to specified
  22  * con_mon grp, mon_grp in resctrl FS.
  23  * For each allocation, run 5 times in order to get average values.
  24  */
  25 static int mba_setup(struct resctrl_val_param *p)
  26 {
  27         static int runs_per_allocation, allocation = 100;
  28         char allocation_str[64];
  29         int ret;
  30
  31         if (runs_per_allocation >= NUM_OF_RUNS)
  32                 runs_per_allocation = 0;
  33
  34         /* Only set up schemata once every NUM_OF_RUNS of allocations */
  35         if (runs_per_allocation++ != 0)
  36                 return 0;
  37
  38         if (allocation < ALLOCATION_MIN || allocation > ALLOCATION_MAX)
  39                 return END_OF_TESTS;
  40
  41         sprintf(allocation_str, "%d", allocation);
  42
  43         ret = write_schemata(p->ctrlgrp, allocation_str, p->cpu_no,
  44                              p->resctrl_val);
  45         if (ret < 0)
  46                 return ret;
  47
  48         allocation -= ALLOCATION_STEP;
  49
  50         return 0;
  51 }
  52
  53 static bool show_mba_info(unsigned long *bw_imc, unsigned long *bw_resc)
  54 {
  55         int allocation, runs;
  56         bool ret = false;
  57
  58         ksft_print_msg("Results are displayed in (MB)\n");
  59         /* Memory bandwidth from 100% down to 10% */
  60         for (allocation = 0; allocation < ALLOCATION_MAX / ALLOCATION_STEP;
  61              allocation++) {
  62                 unsigned long avg_bw_imc, avg_bw_resc;
  63                 unsigned long sum_bw_imc = 0, sum_bw_resc = 0;
  64                 int avg_diff_per;
  65                 float avg_diff;
  66
  67                 /*
  68                  * The first run is discarded due to inaccurate value from
  69                  * phase transition.
  70                  */
  71                 for (runs = NUM_OF_RUNS * allocation + 1;
  72                      runs < NUM_OF_RUNS * allocation + NUM_OF_RUNS ; runs++) {
  73                         sum_bw_imc += bw_imc[runs];
  74                         sum_bw_resc += bw_resc[runs];
  75                 }
  76
  77                 avg_bw_imc = sum_bw_imc / (NUM_OF_RUNS - 1);
  78                 avg_bw_resc = sum_bw_resc / (NUM_OF_RUNS - 1);
  79                 avg_diff = (float)labs(avg_bw_resc - avg_bw_imc) / avg_bw_imc;
  80                 avg_diff_per = (int)(avg_diff * 100);
  81
  82                 ksft_print_msg("%s Check MBA diff within %d%% for schemata %u\n",
  83                                avg_diff_per > MAX_DIFF_PERCENT ?
  84                                "Fail:" : "Pass:",
  85                                MAX_DIFF_PERCENT,
  86                                ALLOCATION_MAX - ALLOCATION_STEP * allocation);
  87
  88                 ksft_print_msg("avg_diff_per: %d%%\n", avg_diff_per);
  89                 ksft_print_msg("avg_bw_imc: %lu\n", avg_bw_imc);
  90                 ksft_print_msg("avg_bw_resc: %lu\n", avg_bw_resc);
  91                 if (avg_diff_per > MAX_DIFF_PERCENT)
  92                         ret = true;
  93         }
  94
  95         ksft_print_msg("%s Check schemata change using MBA\n",
  96                        ret ? "Fail:" : "Pass:");
  97         if (ret)
  98                 ksft_print_msg("At least one test failed\n");
  99
 100         return ret;
 101 }
 102
 103 static int check_results(void)
 104 {
 105         char *token_array[8], output[] = RESULT_FILE_NAME, temp[512];
 106         unsigned long bw_imc[1024], bw_resc[1024];
 107         int runs;
 108         FILE *fp;
 109
 110         fp = fopen(output, "r");
 111         if (!fp) {
 112                 perror(output);
 113
 114                 return errno;
 115         }
 116
 117         runs = 0;
 118         while (fgets(temp, sizeof(temp), fp)) {
 119                 char *token = strtok(temp, ":\t");
 120                 int fields = 0;
 121
 122                 while (token) {
 123                         token_array[fields++] = token;
 124                         token = strtok(NULL, ":\t");
 125                 }
 126
 127                 /* Field 3 is perf imc value */
 128                 bw_imc[runs] = strtoul(token_array[3], NULL, 0);
 129                 /* Field 5 is resctrl value */
 130                 bw_resc[runs] = strtoul(token_array[5], NULL, 0);
 131                 runs++;
 132         }
 133
 134         fclose(fp);
 135
 136         return show_mba_info(bw_imc, bw_resc);
 137 }
 138
 139 void mba_test_cleanup(void)
 140 {
 141         remove(RESULT_FILE_NAME);
 142 }
 143
 144 int mba_schemata_change(int cpu_no, char *bw_report, char **benchmark_cmd)
 145 {
 146         struct resctrl_val_param param = {
 147                 .resctrl_val    = MBA_STR,
 148                 .ctrlgrp        = "c1",
 149                 .mongrp         = "m1",
 150                 .cpu_no         = cpu_no,
 151                 .filename       = RESULT_FILE_NAME,
 152                 .bw_report      = bw_report,
 153                 .setup          = mba_setup
 154         };
 155         int ret;
 156
 157         remove(RESULT_FILE_NAME);
 158
 159         ret = resctrl_val(benchmark_cmd, &param);
 160         if (ret)
 161                 goto out;
 162
 163         ret = check_results();
 164
 165 out:
 166         mba_test_cleanup();
 167
 168         return ret;
 169 }