LXR linux/tools/testing/selftests/powerpc/math/vmx

   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 VMX registers are correctly reported in a
  10 * signal context. Each worker just spins checking its VMX registers, at some
  11 * point a signal will interrupt it and C code will check the signal context
  12 * ensuring it is also the same.
  13 */
  14
  15#include <stdio.h>
  16#include <unistd.h>
  17#include <sys/syscall.h>
  18#include <sys/time.h>
  19#include <sys/types.h>
  20#include <sys/wait.h>
  21#include <stdlib.h>
  22#include <string.h>
  23#include <pthread.h>
  24#include <altivec.h>
  25
  26#include "utils.h"
  27
  28/* Number of times each thread should receive the signal */
  29#define ITERATIONS 10
  30/*
  31 * Factor by which to multiply number of online CPUs for total number of
  32 * worker threads
  33 */
  34#define THREAD_FACTOR 8
  35
  36__thread vector int varray[] = {{1, 2, 3, 4}, {5, 6, 7, 8}, {9, 10,11,12},
  37        {13,14,15,16},{17,18,19,20},{21,22,23,24},
  38        {25,26,27,28},{29,30,31,32},{33,34,35,36},
  39        {37,38,39,40},{41,42,43,44},{45,46,47,48}};
  40
  41bool bad_context;
  42int running;
  43int threads_starting;
  44
  45extern int preempt_vmx(vector int *varray, int *threads_starting, int *sentinal);
  46
  47void signal_vmx_sig(int sig, siginfo_t *info, void *context)
  48{
  49        int i;
  50        ucontext_t *uc = context;
  51        mcontext_t *mc = &uc->uc_mcontext;
  52
  53        /* Only the non volatiles were loaded up */
  54        for (i = 20; i < 32; i++) {
  55                if (memcmp(mc->v_regs->vrregs[i], &varray[i - 20], 16)) {
  56                        int j;
  57                        /*
  58                         * Shouldn't printf() in a signal handler, however, this is a
  59                         * test and we've detected failure. Understanding what failed
  60                         * is paramount. All that happens after this is tests exit with
  61                         * failure.
  62                         */
  63                        printf("VMX mismatch at reg %d!\n", i);
  64                        printf("Reg | Actual                  | Expected\n");
  65                        for (j = 20; j < 32; j++) {
  66                                printf("%d  | 0x%04x%04x%04x%04x      | 0x%04x%04x%04x%04x\n", j, mc->v_regs->vrregs[j][0],
  67                                           mc->v_regs->vrregs[j][1], mc->v_regs->vrregs[j][2], mc->v_regs->vrregs[j][3],
  68                                           varray[j - 20][0], varray[j - 20][1], varray[j - 20][2], varray[j - 20][3]);
  69                        }
  70                        bad_context = true;
  71                        break;
  72                }
  73        }
  74}
  75
  76void *signal_vmx_c(void *p)
  77{
  78        int i, j;
  79        long rc;
  80        struct sigaction act;
  81        act.sa_sigaction = signal_vmx_sig;
  82        act.sa_flags = SA_SIGINFO;
  83        rc = sigaction(SIGUSR1, &act, NULL);
  84        if (rc)
  85                return p;
  86
  87        srand(pthread_self());
  88        for (i = 0; i < 12; i++)
  89                for (j = 0; j < 4; j++)
  90                        varray[i][j] = rand();
  91
  92        rc = preempt_vmx(varray, &threads_starting, &running);
  93
  94        return (void *) rc;
  95}
  96
  97int test_signal_vmx(void)
  98{
  99        int i, j, rc, threads;
 100        void *rc_p;
 101        pthread_t *tids;
 102
 103        threads = sysconf(_SC_NPROCESSORS_ONLN) * THREAD_FACTOR;
 104        tids = malloc(threads * sizeof(pthread_t));
 105        FAIL_IF(!tids);
 106
 107        running = true;
 108        threads_starting = threads;
 109        for (i = 0; i < threads; i++) {
 110                rc = pthread_create(&tids[i], NULL, signal_vmx_c, NULL);
 111                FAIL_IF(rc);
 112        }
 113
 114        setbuf(stdout, NULL);
 115        printf("\tWaiting for %d workers to start... %d", threads, threads_starting);
 116        while (threads_starting) {
 117                asm volatile("": : :"memory");
 118                usleep(1000);
 119                printf(", %d", threads_starting);
 120        }
 121        printf(" ...done\n");
 122
 123        printf("\tSending signals to all threads %d times...", ITERATIONS);
 124        for (i = 0; i < ITERATIONS; i++) {
 125                for (j = 0; j < threads; j++) {
 126                        pthread_kill(tids[j], SIGUSR1);
 127                }
 128                sleep(1);
 129        }
 130        printf("done\n");
 131
 132        printf("\tKilling workers...");
 133        running = 0;
 134        for (i = 0; i < threads; i++) {
 135                pthread_join(tids[i], &rc_p);
 136
 137                /*
 138                 * Harness will say the fail was here, look at why signal_vmx
 139                 * returned
 140                 */
 141                if ((long) rc_p || bad_context)
 142                        printf("oops\n");
 143                if (bad_context)
 144                        fprintf(stderr, "\t!! bad_context is true\n");
 145                FAIL_IF((long) rc_p || bad_context);
 146        }
 147        printf("done\n");
 148
 149        free(tids);
 150        return 0;
 151}
 152
 153int main(int argc, char *argv[])
 154{
 155        return test_harness(test_signal_vmx, "vmx_signal");
 156}
 157