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 
dhry_benchmark(void)32 static void dhry_benchmark(void)
33 {
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 	if (n >= 0)
49 		pr_info("CPU%u: Dhrystones per Second: %d (%d DMIPS)\n",
50 			smp_processor_id(), n, n / DHRY_VAX);
51 	else if (n == -EAGAIN)
52 		pr_err("Please increase the number of iterations\n");
53 	else
54 		pr_err("Dhrystone benchmark failed error %pe\n", ERR_PTR(n));
55 }
56 
dhry_run_set(const char * val,const struct kernel_param * kp)57 static int dhry_run_set(const char *val, const struct kernel_param *kp)
58 {
59 	int ret;
60 
61 	if (val) {
62 		ret = param_set_bool(val, kp);
63 		if (ret)
64 			return ret;
65 	} else {
66 		dhry_run = true;
67 	}
68 
69 	if (dhry_run && system_state == SYSTEM_RUNNING)
70 		dhry_benchmark();
71 
72 	return 0;
73 }
74 
dhry_init(void)75 static int __init dhry_init(void)
76 {
77 	if (dhry_run)
78 		dhry_benchmark();
79 
80 	return 0;
81 }
82 module_init(dhry_init);
83 
84 MODULE_AUTHOR("Geert Uytterhoeven <geert+renesas@glider.be>");
85 MODULE_LICENSE("GPL");
86