128 lines · c
1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright 2015, Cyril Bur, IBM Corp.4 *5 * This test attempts to see if the FPU registers are correctly reported in a6 * signal context. Each worker just spins checking its FPU registers, at some7 * point a signal will interrupt it and C code will check the signal context8 * ensuring it is also the same.9 */10 11#include <stdio.h>12#include <unistd.h>13#include <sys/syscall.h>14#include <sys/time.h>15#include <sys/types.h>16#include <sys/wait.h>17#include <stdlib.h>18#include <pthread.h>19 20#include "utils.h"21#include "fpu.h"22 23/* Number of times each thread should receive the signal */24#define ITERATIONS 1025/*26 * Factor by which to multiply number of online CPUs for total number of27 * worker threads28 */29#define THREAD_FACTOR 830 31__thread double darray[32];32 33bool bad_context;34int threads_starting;35int running;36 37extern long preempt_fpu(double *darray, int *threads_starting, int *running);38 39void signal_fpu_sig(int sig, siginfo_t *info, void *context)40{41 int i;42 ucontext_t *uc = context;43 mcontext_t *mc = &uc->uc_mcontext;44 45 // Don't check f30/f31, they're used as scratches in check_all_fprs()46 for (i = 0; i < 30; i++) {47 if (mc->fp_regs[i] != darray[i]) {48 bad_context = true;49 break;50 }51 }52}53 54void *signal_fpu_c(void *p)55{56 long rc;57 struct sigaction act;58 act.sa_sigaction = signal_fpu_sig;59 act.sa_flags = SA_SIGINFO;60 rc = sigaction(SIGUSR1, &act, NULL);61 if (rc)62 return p;63 64 srand(pthread_self());65 randomise_darray(darray, ARRAY_SIZE(darray));66 rc = preempt_fpu(darray, &threads_starting, &running);67 68 return (void *) rc;69}70 71int test_signal_fpu(void)72{73 int i, j, rc, threads;74 void *rc_p;75 pthread_t *tids;76 77 threads = sysconf(_SC_NPROCESSORS_ONLN) * THREAD_FACTOR;78 tids = malloc(threads * sizeof(pthread_t));79 FAIL_IF(!tids);80 81 running = true;82 threads_starting = threads;83 for (i = 0; i < threads; i++) {84 rc = pthread_create(&tids[i], NULL, signal_fpu_c, NULL);85 FAIL_IF(rc);86 }87 88 setbuf(stdout, NULL);89 printf("\tWaiting for all workers to start...");90 while (threads_starting)91 asm volatile("": : :"memory");92 printf("done\n");93 94 printf("\tSending signals to all threads %d times...", ITERATIONS);95 for (i = 0; i < ITERATIONS; i++) {96 for (j = 0; j < threads; j++) {97 pthread_kill(tids[j], SIGUSR1);98 }99 sleep(1);100 }101 printf("done\n");102 103 printf("\tStopping workers...");104 running = 0;105 for (i = 0; i < threads; i++) {106 pthread_join(tids[i], &rc_p);107 108 /*109 * Harness will say the fail was here, look at why signal_fpu110 * returned111 */112 if ((long) rc_p || bad_context)113 printf("oops\n");114 if (bad_context)115 fprintf(stderr, "\t!! bad_context is true\n");116 FAIL_IF((long) rc_p || bad_context);117 }118 printf("done\n");119 120 free(tids);121 return 0;122}123 124int main(int argc, char *argv[])125{126 return test_harness(test_signal_fpu, "fpu_signal");127}128