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      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 
     41 bool bad_context;
     42 int running;
     43 int threads_starting;
     44 
     45 extern int preempt_vmx(vector int *varray, int *threads_starting, int *sentinal);
     46 
     47 void 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 
     76 void *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 
     97 int 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 
    153 int main(int argc, char *argv[])
    154 {
    155 	return test_harness(test_signal_vmx, "vmx_signal");
    156 }
    157