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                300
  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(int num, ...)
  26 {
  27         static int runs_per_allocation, allocation = 100;
  28         struct resctrl_val_param *p;
  29         char allocation_str[64];
  30         va_list param;
  31
  32         va_start(param, num);
  33         p = va_arg(param, struct resctrl_val_param *);
  34         va_end(param);
  35
  36         if (runs_per_allocation >= NUM_OF_RUNS)
  37                 runs_per_allocation = 0;
  38
  39         /* Only set up schemata once every NUM_OF_RUNS of allocations */
  40         if (runs_per_allocation++ != 0)
  41                 return 0;
  42
  43         if (allocation < ALLOCATION_MIN || allocation > ALLOCATION_MAX)
  44                 return -1;
  45
  46         sprintf(allocation_str, "%d", allocation);
  47
  48         write_schemata(p->ctrlgrp, allocation_str, p->cpu_no, p->resctrl_val);
  49         allocation -= ALLOCATION_STEP;
  50
  51         return 0;
  52 }
  53
  54 static void show_mba_info(unsigned long *bw_imc, unsigned long *bw_resc)
  55 {
  56         int allocation, runs;
  57         bool failed = false;
  58
  59         printf("# Results are displayed in (MB)\n");
  60         /* Memory bandwidth from 100% down to 10% */
  61         for (allocation = 0; allocation < ALLOCATION_MAX / ALLOCATION_STEP;
  62              allocation++) {
  63                 unsigned long avg_bw_imc, avg_bw_resc;
  64                 unsigned long sum_bw_imc = 0, sum_bw_resc = 0;
  65                 unsigned long 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 = labs((long)(avg_bw_resc - avg_bw_imc));
  80
  81                 printf("%sok MBA schemata percentage %u smaller than %d %%\n",
  82                        avg_diff > MAX_DIFF ? "not " : "",
  83                        ALLOCATION_MAX - ALLOCATION_STEP * allocation,
  84                        MAX_DIFF);
  85                 tests_run++;
  86                 printf("# avg_diff: %lu\n", avg_diff);
  87                 printf("# avg_bw_imc: %lu\n", avg_bw_imc);
  88                 printf("# avg_bw_resc: %lu\n", avg_bw_resc);
  89                 if (avg_diff > MAX_DIFF)
  90                         failed = true;
  91         }
  92
  93         printf("%sok schemata change using MBA%s\n", failed ? "not " : "",
  94                failed ? " # at least one test failed" : "");
  95         tests_run++;
  96 }
  97
  98 static int check_results(void)
  99 {
 100         char *token_array[8], output[] = RESULT_FILE_NAME, temp[512];
 101         unsigned long bw_imc[1024], bw_resc[1024];
 102         int runs;
 103         FILE *fp;
 104
 105         fp = fopen(output, "r");
 106         if (!fp) {
 107                 perror(output);
 108
 109                 return errno;
 110         }
 111
 112         runs = 0;
 113         while (fgets(temp, sizeof(temp), fp)) {
 114                 char *token = strtok(temp, ":\t");
 115                 int fields = 0;
 116
 117                 while (token) {
 118                         token_array[fields++] = token;
 119                         token = strtok(NULL, ":\t");
 120                 }
 121
 122                 /* Field 3 is perf imc value */
 123                 bw_imc[runs] = strtoul(token_array[3], NULL, 0);
 124                 /* Field 5 is resctrl value */
 125                 bw_resc[runs] = strtoul(token_array[5], NULL, 0);
 126                 runs++;
 127         }
 128
 129         fclose(fp);
 130
 131         show_mba_info(bw_imc, bw_resc);
 132
 133         return 0;
 134 }
 135
 136 void mba_test_cleanup(void)
 137 {
 138         remove(RESULT_FILE_NAME);
 139 }
 140
 141 int mba_schemata_change(int cpu_no, char *bw_report, char **benchmark_cmd)
 142 {
 143         struct resctrl_val_param param = {
 144                 .resctrl_val    = "mba",
 145                 .ctrlgrp        = "c1",
 146                 .mongrp         = "m1",
 147                 .cpu_no         = cpu_no,
 148                 .mum_resctrlfs  = 1,
 149                 .filename       = RESULT_FILE_NAME,
 150                 .bw_report      = bw_report,
 151                 .setup          = mba_setup
 152         };
 153         int ret;
 154
 155         remove(RESULT_FILE_NAME);
 156
 157         if (!validate_resctrl_feature_request("mba"))
 158                 return -1;
 159
 160         ret = resctrl_val(benchmark_cmd, &param);
 161         if (ret)
 162                 return ret;
 163
 164         ret = check_results();
 165         if (ret)
 166                 return ret;
 167
 168         mba_test_cleanup();
 169
 170         return 0;
 171 }