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 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
dhry_run_set(const char * val,const struct kernel_param * kp)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
dhry_init(void)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