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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 VMX registers change across preemption.6 * Two things should be noted here a) The check_vmx function in asm only checks7 * the non volatile registers as it is reused from the syscall test b) There is8 * no way to be sure preemption happened so this test just uses many threads9 * and a long wait. As such, a successful test doesn't mean much but a failure10 * is bad.11 */12 13#include <stdio.h>14#include <unistd.h>15#include <sys/syscall.h>16#include <sys/time.h>17#include <sys/types.h>18#include <sys/wait.h>19#include <stdlib.h>20#include <pthread.h>21 22#include "utils.h"23 24/* Time to wait for workers to get preempted (seconds) */25#define PREEMPT_TIME 2026/*27 * Factor by which to multiply number of online CPUs for total number of28 * worker threads29 */30#define THREAD_FACTOR 831 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 37int threads_starting;38int running;39 40extern int preempt_vmx(vector int *varray, int *threads_starting, int *running);41 42void *preempt_vmx_c(void *p)43{44	int i, j;45	long rc;46 47	srand(pthread_self());48	for (i = 0; i < 12; i++)49		for (j = 0; j < 4; j++)50			varray[i][j] = rand();51 52	rc = preempt_vmx(varray, &threads_starting, &running);53 54	return (void *)rc;55}56 57int test_preempt_vmx(void)58{59	int i, rc, threads;60	pthread_t *tids;61 62	// vcmpequd used in vmx_asm.S is v2.0763	SKIP_IF(!have_hwcap2(PPC_FEATURE2_ARCH_2_07));64 65	threads = sysconf(_SC_NPROCESSORS_ONLN) * THREAD_FACTOR;66	tids = malloc(threads * sizeof(pthread_t));67	FAIL_IF(!tids);68 69	running = true;70	threads_starting = threads;71	for (i = 0; i < threads; i++) {72		rc = pthread_create(&tids[i], NULL, preempt_vmx_c, NULL);73		FAIL_IF(rc);74	}75 76	setbuf(stdout, NULL);77	/* Not really nessesary but nice to wait for every thread to start */78	printf("\tWaiting for all workers to start...");79	while(threads_starting)80		asm volatile("": : :"memory");81	printf("done\n");82 83	printf("\tWaiting for %d seconds to let some workers get preempted...", PREEMPT_TIME);84	sleep(PREEMPT_TIME);85	printf("done\n");86 87	printf("\tStopping workers...");88	/*89	 * Working are checking this value every loop. In preempt_vmx 'cmpwi r5,0; bne 2b'.90	 * r5 will have loaded the value of running.91	 */92	running = 0;93	for (i = 0; i < threads; i++) {94		void *rc_p;95		pthread_join(tids[i], &rc_p);96 97		/*98		 * Harness will say the fail was here, look at why preempt_vmx99		 * returned100		 */101		if ((long) rc_p)102			printf("oops\n");103		FAIL_IF((long) rc_p);104	}105	printf("done\n");106 107	return 0;108}109 110int main(int argc, char *argv[])111{112	return test_harness(test_preempt_vmx, "vmx_preempt");113}114