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/smp.h>
14  
15  #define DHRY_VAX	1757
16  
17  static int dhry_run_set(const char *val, const struct kernel_param *kp);
18  static const struct kernel_param_ops run_ops = {
19  	.flags = KERNEL_PARAM_OPS_FL_NOARG,
20  	.set = dhry_run_set,
21  };
22  static bool dhry_run;
23  module_param_cb(run, &run_ops, &dhry_run, 0200);
24  MODULE_PARM_DESC(run, "Run the test (default: false)");
25  
26  static int iterations = -1;
27  module_param(iterations, int, 0644);
28  MODULE_PARM_DESC(iterations,
29  		"Number of iterations through the benchmark (default: auto)");
30  
dhry_benchmark(void)31  static void dhry_benchmark(void)
32  {
33  	unsigned int cpu = get_cpu();
34  	int i, n;
35  
36  	if (iterations > 0) {
37  		n = dhry(iterations);
38  		goto report;
39  	}
40  
41  	for (i = DHRY_VAX; i > 0; i <<= 1) {
42  		n = dhry(i);
43  		if (n != -EAGAIN)
44  			break;
45  	}
46  
47  report:
48  	put_cpu();
49  	if (n >= 0)
50  		pr_info("CPU%u: Dhrystones per Second: %d (%d DMIPS)\n", cpu,
51  			n, n / DHRY_VAX);
52  	else if (n == -EAGAIN)
53  		pr_err("Please increase the number of iterations\n");
54  	else
55  		pr_err("Dhrystone benchmark failed error %pe\n", ERR_PTR(n));
56  }
57  
dhry_run_set(const char * val,const struct kernel_param * kp)58  static int dhry_run_set(const char *val, const struct kernel_param *kp)
59  {
60  	int ret;
61  
62  	if (val) {
63  		ret = param_set_bool(val, kp);
64  		if (ret)
65  			return ret;
66  	} else {
67  		dhry_run = true;
68  	}
69  
70  	if (dhry_run && system_state == SYSTEM_RUNNING)
71  		dhry_benchmark();
72  
73  	return 0;
74  }
75  
dhry_init(void)76  static int __init dhry_init(void)
77  {
78  	if (dhry_run)
79  		dhry_benchmark();
80  
81  	return 0;
82  }
83  module_init(dhry_init);
84  
85  MODULE_AUTHOR("Geert Uytterhoeven <geert+renesas@glider.be>");
86  MODULE_DESCRIPTION("Dhrystone benchmark test module");
87  MODULE_LICENSE("GPL");
88