tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
fork
Configure Feed
Select the types of activity you want to include in your feed.
1/*
2 * Copyright 2015, Cyril Bur, IBM Corp.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 *
9 * This test attempts to see if the FPU registers change across a syscall (fork).
10 */
11
12#include <stdio.h>
13#include <unistd.h>
14#include <sys/syscall.h>
15#include <sys/time.h>
16#include <sys/types.h>
17#include <sys/wait.h>
18#include <stdlib.h>
19
20#include "utils.h"
21
22extern int test_fpu(double *darray, pid_t *pid);
23
24double darray[] = {0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0,
25 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0,
26 2.1};
27
28int syscall_fpu(void)
29{
30 pid_t fork_pid;
31 int i;
32 int ret;
33 int child_ret;
34 for (i = 0; i < 1000; i++) {
35 /* test_fpu will fork() */
36 ret = test_fpu(darray, &fork_pid);
37 if (fork_pid == -1)
38 return -1;
39 if (fork_pid == 0)
40 exit(ret);
41 waitpid(fork_pid, &child_ret, 0);
42 if (ret || child_ret)
43 return 1;
44 }
45
46 return 0;
47}
48
49int test_syscall_fpu(void)
50{
51 /*
52 * Setup an environment with much context switching
53 */
54 pid_t pid2;
55 pid_t pid = fork();
56 int ret;
57 int child_ret;
58 FAIL_IF(pid == -1);
59
60 pid2 = fork();
61 /* Can't FAIL_IF(pid2 == -1); because already forked once */
62 if (pid2 == -1) {
63 /*
64 * Couldn't fork, ensure test is a fail
65 */
66 child_ret = ret = 1;
67 } else {
68 ret = syscall_fpu();
69 if (pid2)
70 waitpid(pid2, &child_ret, 0);
71 else
72 exit(ret);
73 }
74
75 ret |= child_ret;
76
77 if (pid)
78 waitpid(pid, &child_ret, 0);
79 else
80 exit(ret);
81
82 FAIL_IF(ret || child_ret);
83 return 0;
84}
85
86int main(int argc, char *argv[])
87{
88 return test_harness(test_syscall_fpu, "syscall_fpu");
89
90}