summaryrefslogtreecommitdiffstats
path: root/tools/testing/selftests/powerpc/math/fpu_signal.c
blob: 7b1addd504209fadb59f908a843b23a9d0218f3f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright 2015, Cyril Bur, IBM Corp.
 *
 * This test attempts to see if the FPU registers are correctly reported in a
 * signal context. Each worker just spins checking its FPU registers, at some
 * point a signal will interrupt it and C code will check the signal context
 * ensuring it is also the same.
 */

#include <stdio.h>
#include <unistd.h>
#include <sys/syscall.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <stdlib.h>
#include <pthread.h>

#include "utils.h"

/* Number of times each thread should receive the signal */
#define ITERATIONS 10
/*
 * Factor by which to multiply number of online CPUs for total number of
 * worker threads
 */
#define THREAD_FACTOR 8

__thread double darray[] = {0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0,
		     1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0,
		     2.1};

bool bad_context;
int threads_starting;
int running;

extern long preempt_fpu(double *darray, int *threads_starting, int *running);

void signal_fpu_sig(int sig, siginfo_t *info, void *context)
{
	int i;
	ucontext_t *uc = context;
	mcontext_t *mc = &uc->uc_mcontext;

	/* Only the non volatiles were loaded up */
	for (i = 14; i < 32; i++) {
		if (mc->fp_regs[i] != darray[i - 14]) {
			bad_context = true;
			break;
		}
	}
}

void *signal_fpu_c(void *p)
{
	int i;
	long rc;
	struct sigaction act;
	act.sa_sigaction = signal_fpu_sig;
	act.sa_flags = SA_SIGINFO;
	rc = sigaction(SIGUSR1, &act, NULL);
	if (rc)
		return p;

	srand(pthread_self());
	for (i = 0; i < 21; i++)
		darray[i] = rand();

	rc = preempt_fpu(darray, &threads_starting, &running);

	return (void *) rc;
}

int test_signal_fpu(void)
{
	int i, j, rc, threads;
	void *rc_p;
	pthread_t *tids;

	threads = sysconf(_SC_NPROCESSORS_ONLN) * THREAD_FACTOR;
	tids = malloc(threads * sizeof(pthread_t));
	FAIL_IF(!tids);

	running = true;
	threads_starting = threads;
	for (i = 0; i < threads; i++) {
		rc = pthread_create(&tids[i], NULL, signal_fpu_c, NULL);
		FAIL_IF(rc);
	}

	setbuf(stdout, NULL);
	printf("\tWaiting for all workers to start...");
	while (threads_starting)
		asm volatile("": : :"memory");
	printf("done\n");

	printf("\tSending signals to all threads %d times...", ITERATIONS);
	for (i = 0; i < ITERATIONS; i++) {
		for (j = 0; j < threads; j++) {
			pthread_kill(tids[j], SIGUSR1);
		}
		sleep(1);
	}
	printf("done\n");

	printf("\tStopping workers...");
	running = 0;
	for (i = 0; i < threads; i++) {
		pthread_join(tids[i], &rc_p);

		/*
		 * Harness will say the fail was here, look at why signal_fpu
		 * returned
		 */
		if ((long) rc_p || bad_context)
			printf("oops\n");
		if (bad_context)
			fprintf(stderr, "\t!! bad_context is true\n");
		FAIL_IF((long) rc_p || bad_context);
	}
	printf("done\n");

	free(tids);
	return 0;
}

int main(int argc, char *argv[])
{
	return test_harness(test_signal_fpu, "fpu_signal");
}