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

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Copyright 2015, Cyril Bur, IBM Corp.
   4 *
   5 * This test attempts to see if the VMX registers are correctly reported in a
   6 * signal context. Each worker just spins checking its VMX registers, at some
   7 * point a signal will interrupt it and C code will check the signal context
   8 * 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 <string.h>
  19#include <pthread.h>
  20#include <altivec.h>
  21
  22#include "utils.h"
  23
  24/* Number of times each thread should receive the signal */
  25#define ITERATIONS 10
  26/*
  27 * Factor by which to multiply number of online CPUs for total number of
  28 * worker threads
  29 */
  30#define THREAD_FACTOR 8
  31
  32__thread vector int varray[] = {{1, 2, 3, 4}, {5, 6, 7, 8}, {9, 10,11,12},
  33        {13,14,15,16},{17,18,19,20},{21,22,23,24},
  34        {25,26,27,28},{29,30,31,32},{33,34,35,36},
  35        {37,38,39,40},{41,42,43,44},{45,46,47,48}};
  36
  37bool bad_context;
  38int running;
  39int threads_starting;
  40
  41extern int preempt_vmx(vector int *varray, int *threads_starting, int *sentinal);
  42
  43void signal_vmx_sig(int sig, siginfo_t *info, void *context)
  44{
  45        int i;
  46        ucontext_t *uc = context;
  47        mcontext_t *mc = &uc->uc_mcontext;
  48
  49        /* Only the non volatiles were loaded up */
  50        for (i = 20; i < 32; i++) {
  51                if (memcmp(mc->v_regs->vrregs[i], &varray[i - 20], 16)) {
  52                        int j;
  53                        /*
  54                         * Shouldn't printf() in a signal handler, however, this is a
  55                         * test and we've detected failure. Understanding what failed
  56                         * is paramount. All that happens after this is tests exit with
  57                         * failure.
  58                         */
  59                        printf("VMX mismatch at reg %d!\n", i);
  60                        printf("Reg | Actual                  | Expected\n");
  61                        for (j = 20; j < 32; j++) {
  62                                printf("%d  | 0x%04x%04x%04x%04x      | 0x%04x%04x%04x%04x\n", j, mc->v_regs->vrregs[j][0],
  63                                           mc->v_regs->vrregs[j][1], mc->v_regs->vrregs[j][2], mc->v_regs->vrregs[j][3],
  64                                           varray[j - 20][0], varray[j - 20][1], varray[j - 20][2], varray[j - 20][3]);
  65                        }
  66                        bad_context = true;
  67                        break;
  68                }
  69        }
  70}
  71
  72void *signal_vmx_c(void *p)
  73{
  74        int i, j;
  75        long rc;
  76        struct sigaction act;
  77        act.sa_sigaction = signal_vmx_sig;
  78        act.sa_flags = SA_SIGINFO;
  79        rc = sigaction(SIGUSR1, &act, NULL);
  80        if (rc)
  81                return p;
  82
  83        srand(pthread_self());
  84        for (i = 0; i < 12; i++)
  85                for (j = 0; j < 4; j++)
  86                        varray[i][j] = rand();
  87
  88        rc = preempt_vmx(varray, &threads_starting, &running);
  89
  90        return (void *) rc;
  91}
  92
  93int test_signal_vmx(void)
  94{
  95        int i, j, rc, threads;
  96        void *rc_p;
  97        pthread_t *tids;
  98
  99        // vcmpequd used in vmx_asm.S is v2.07
 100        SKIP_IF(!have_hwcap2(PPC_FEATURE2_ARCH_2_07));
 101
 102        threads = sysconf(_SC_NPROCESSORS_ONLN) * THREAD_FACTOR;
 103        tids = malloc(threads * sizeof(pthread_t));
 104        FAIL_IF(!tids);
 105
 106        running = true;
 107        threads_starting = threads;
 108        for (i = 0; i < threads; i++) {
 109                rc = pthread_create(&tids[i], NULL, signal_vmx_c, NULL);
 110                FAIL_IF(rc);
 111        }
 112
 113        setbuf(stdout, NULL);
 114        printf("\tWaiting for %d workers to start... %d", threads, threads_starting);
 115        while (threads_starting) {
 116                asm volatile("": : :"memory");
 117                usleep(1000);
 118                printf(", %d", threads_starting);
 119        }
 120        printf(" ...done\n");
 121
 122        printf("\tSending signals to all threads %d times...", ITERATIONS);
 123        for (i = 0; i < ITERATIONS; i++) {
 124                for (j = 0; j < threads; j++) {
 125                        pthread_kill(tids[j], SIGUSR1);
 126                }
 127                sleep(1);
 128        }
 129        printf("done\n");
 130
 131        printf("\tKilling workers...");
 132        running = 0;
 133        for (i = 0; i < threads; i++) {
 134                pthread_join(tids[i], &rc_p);
 135
 136                /*
 137                 * Harness will say the fail was here, look at why signal_vmx
 138                 * returned
 139                 */
 140                if ((long) rc_p || bad_context)
 141                        printf("oops\n");
 142                if (bad_context)
 143                        fprintf(stderr, "\t!! bad_context is true\n");
 144                FAIL_IF((long) rc_p || bad_context);
 145        }
 146        printf("done\n");
 147
 148        free(tids);
 149        return 0;
 150}
 151
 152int main(int argc, char *argv[])
 153{
 154        return test_harness(test_signal_vmx, "vmx_signal");
 155}
 156