1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * POWER Data Stream Control Register (DSCR) sysfs thread test
4 *
5 * This test updates the system wide DSCR default value through
6 * sysfs interface which should then update all the CPU specific
7 * DSCR default values which must also be then visible to threads
8 * executing on individual CPUs on the system.
9 *
10 * Copyright 2015, Anshuman Khandual, IBM Corporation.
11 */
12#define _GNU_SOURCE
13#include "dscr.h"
14
15static int test_thread_dscr(unsigned long val)
16{
17	unsigned long cur_dscr, cur_dscr_usr;
18
19	cur_dscr = get_dscr();
20	cur_dscr_usr = get_dscr_usr();
21
22	if (val != cur_dscr) {
23		printf("[cpu %d] Kernel DSCR should be %ld but is %ld\n",
24					sched_getcpu(), val, cur_dscr);
25		return 1;
26	}
27
28	if (val != cur_dscr_usr) {
29		printf("[cpu %d] User DSCR should be %ld but is %ld\n",
30					sched_getcpu(), val, cur_dscr_usr);
31		return 1;
32	}
33	return 0;
34}
35
36static int check_cpu_dscr_thread(unsigned long val)
37{
38	cpu_set_t mask;
39	int cpu;
40
41	for (cpu = 0; cpu < CPU_SETSIZE; cpu++) {
42		CPU_ZERO(&mask);
43		CPU_SET(cpu, &mask);
44		if (sched_setaffinity(0, sizeof(mask), &mask))
45			continue;
46
47		if (test_thread_dscr(val))
48			return 1;
49	}
50	return 0;
51
52}
53
54int dscr_sysfs_thread(void)
55{
56	unsigned long orig_dscr_default;
57	int i, j;
58
59	SKIP_IF(!have_hwcap2(PPC_FEATURE2_DSCR));
60
61	orig_dscr_default = get_default_dscr();
62	for (i = 0; i < COUNT; i++) {
63		for (j = 0; j < DSCR_MAX; j++) {
64			set_default_dscr(j);
65			if (check_cpu_dscr_thread(j))
66				goto fail;
67		}
68	}
69	set_default_dscr(orig_dscr_default);
70	return 0;
71fail:
72	set_default_dscr(orig_dscr_default);
73	return 1;
74}
75
76int main(int argc, char *argv[])
77{
78	return test_harness(dscr_sysfs_thread, "dscr_sysfs_thread_test");
79}
80