LXR linux/tools/testing/selftests/resctrl/mba

   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        5
  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 */
  25static 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
  54static void show_mba_info(unsigned long *bw_imc, unsigned long *bw_resc)
  55{
  56        int allocation, runs;
  57        bool failed = false;
  58
  59        ksft_print_msg("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                int avg_diff_per;
  66                float avg_diff;
  67
  68                /*
  69                 * The first run is discarded due to inaccurate value from
  70                 * phase transition.
  71                 */
  72                for (runs = NUM_OF_RUNS * allocation + 1;
  73                     runs < NUM_OF_RUNS * allocation + NUM_OF_RUNS ; runs++) {
  74                        sum_bw_imc += bw_imc[runs];
  75                        sum_bw_resc += bw_resc[runs];
  76                }
  77
  78                avg_bw_imc = sum_bw_imc / (NUM_OF_RUNS - 1);
  79                avg_bw_resc = sum_bw_resc / (NUM_OF_RUNS - 1);
  80                avg_diff = (float)labs(avg_bw_resc - avg_bw_imc) / avg_bw_imc;
  81                avg_diff_per = (int)(avg_diff * 100);
  82
  83                ksft_print_msg("%s Check MBA diff within %d%% for schemata %u\n",
  84                               avg_diff_per > MAX_DIFF_PERCENT ?
  85                               "Fail:" : "Pass:",
  86                               MAX_DIFF_PERCENT,
  87                               ALLOCATION_MAX - ALLOCATION_STEP * allocation);
  88
  89                ksft_print_msg("avg_diff_per: %d%%\n", avg_diff_per);
  90                ksft_print_msg("avg_bw_imc: %lu\n", avg_bw_imc);
  91                ksft_print_msg("avg_bw_resc: %lu\n", avg_bw_resc);
  92                if (avg_diff_per > MAX_DIFF_PERCENT)
  93                        failed = true;
  94        }
  95
  96        ksft_print_msg("%s Check schemata change using MBA\n",
  97                       failed ? "Fail:" : "Pass:");
  98        if (failed)
  99                ksft_print_msg("At least one test failed\n");
 100}
 101
 102static int check_results(void)
 103{
 104        char *token_array[8], output[] = RESULT_FILE_NAME, temp[512];
 105        unsigned long bw_imc[1024], bw_resc[1024];
 106        int runs;
 107        FILE *fp;
 108
 109        fp = fopen(output, "r");
 110        if (!fp) {
 111                perror(output);
 112
 113                return errno;
 114        }
 115
 116        runs = 0;
 117        while (fgets(temp, sizeof(temp), fp)) {
 118                char *token = strtok(temp, ":\t");
 119                int fields = 0;
 120
 121                while (token) {
 122                        token_array[fields++] = token;
 123                        token = strtok(NULL, ":\t");
 124                }
 125
 126                /* Field 3 is perf imc value */
 127                bw_imc[runs] = strtoul(token_array[3], NULL, 0);
 128                /* Field 5 is resctrl value */
 129                bw_resc[runs] = strtoul(token_array[5], NULL, 0);
 130                runs++;
 131        }
 132
 133        fclose(fp);
 134
 135        show_mba_info(bw_imc, bw_resc);
 136
 137        return 0;
 138}
 139
 140void mba_test_cleanup(void)
 141{
 142        remove(RESULT_FILE_NAME);
 143}
 144
 145int mba_schemata_change(int cpu_no, char *bw_report, char **benchmark_cmd)
 146{
 147        struct resctrl_val_param param = {
 148                .resctrl_val    = MBA_STR,
 149                .ctrlgrp        = "c1",
 150                .mongrp         = "m1",
 151                .cpu_no         = cpu_no,
 152                .mum_resctrlfs  = 1,
 153                .filename       = RESULT_FILE_NAME,
 154                .bw_report      = bw_report,
 155                .setup          = mba_setup
 156        };
 157        int ret;
 158
 159        remove(RESULT_FILE_NAME);
 160
 161        ret = resctrl_val(benchmark_cmd, &param);
 162        if (ret)
 163                return ret;
 164
 165        ret = check_results();
 166        if (ret)
 167                return ret;
 168
 169        mba_test_cleanup();
 170
 171        return 0;
 172}
 173