lib/dhry_run.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Dhrystone benchmark test module
   4  *
   5  * Copyright (C) 2022 Glider bv
   6  */
   7
   8 #include "dhry.h"
   9
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12 #include <linux/moduleparam.h>
  13 #include <linux/mutex.h>
  14 #include <linux/smp.h>
  15
  16 #define DHRY_VAX        1757
  17
  18 static int dhry_run_set(const char *val, const struct kernel_param *kp);
  19 static const struct kernel_param_ops run_ops = {
  20         .flags = KERNEL_PARAM_OPS_FL_NOARG,
  21         .set = dhry_run_set,
  22 };
  23 static bool dhry_run;
  24 module_param_cb(run, &run_ops, &dhry_run, 0200);
  25 MODULE_PARM_DESC(run, "Run the test (default: false)");
  26
  27 static int iterations = -1;
  28 module_param(iterations, int, 0644);
  29 MODULE_PARM_DESC(iterations,
  30                 "Number of iterations through the benchmark (default: auto)");
  31
  32 static void dhry_benchmark(void)
  33 {
  34         unsigned int cpu = get_cpu();
  35         int i, n;
  36
  37         if (iterations > 0) {
  38                 n = dhry(iterations);
  39                 goto report;
  40         }
  41
  42         for (i = DHRY_VAX; i > 0; i <<= 1) {
  43                 n = dhry(i);
  44                 if (n != -EAGAIN)
  45                         break;
  46         }
  47
  48 report:
  49         put_cpu();
  50         if (n >= 0)
  51                 pr_info("CPU%u: Dhrystones per Second: %d (%d DMIPS)\n", cpu,
  52                         n, n / DHRY_VAX);
  53         else if (n == -EAGAIN)
  54                 pr_err("Please increase the number of iterations\n");
  55         else
  56                 pr_err("Dhrystone benchmark failed error %pe\n", ERR_PTR(n));
  57 }
  58
  59 static int dhry_run_set(const char *val, const struct kernel_param *kp)
  60 {
  61         int ret;
  62
  63         if (val) {
  64                 ret = param_set_bool(val, kp);
  65                 if (ret)
  66                         return ret;
  67         } else {
  68                 dhry_run = true;
  69         }
  70
  71         if (dhry_run && system_state == SYSTEM_RUNNING)
  72                 dhry_benchmark();
  73
  74         return 0;
  75 }
  76
  77 static int __init dhry_init(void)
  78 {
  79         if (dhry_run)
  80                 dhry_benchmark();
  81
  82         return 0;
  83 }
  84 module_init(dhry_init);
  85
  86 MODULE_AUTHOR("Geert Uytterhoeven <geert+renesas@glider.be>");
  87 MODULE_LICENSE("GPL");