tools/testing/selftests/powerpc/math/vmx_signal.c

   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
  37 bool bad_context;
  38 int running;
  39 int threads_starting;
  40
  41 extern int preempt_vmx(vector int *varray, int *threads_starting, int *sentinal);
  42
  43 void 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
  72 void *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
  93 int 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
 152 int main(int argc, char *argv[])
 153 {
 154         return test_harness(test_signal_vmx, "vmx_signal");
 155 }