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"); 88