110 lines
2.6 KiB
C
110 lines
2.6 KiB
C
|
// SPDX-License-Identifier: GPL-2.0-or-later
|
||
|
|
/*
|
||
|
|
* Copyright 2015, Cyril Bur, IBM Corp.
|
||
|
|
*
|
||
|
|
* This test attempts to see if the FPU registers change across preemption.
|
||
|
|
* Two things should be noted here a) The check_fpu function in asm only checks
|
||
|
|
* the non volatile registers as it is reused from the syscall test b) There is
|
||
|
|
* no way to be sure preemption happened so this test just uses many threads
|
||
|
|
* and a long wait. As such, a successful test doesn't mean much but a failure
|
||
|
|
* is bad.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <stdio.h>
|
||
|
|
#include <unistd.h>
|
||
|
|
#include <sys/syscall.h>
|
||
|
|
#include <sys/time.h>
|
||
|
|
#include <sys/types.h>
|
||
|
|
#include <sys/wait.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <pthread.h>
|
||
|
|
|
||
|
|
#include "utils.h"
|
||
|
|
|
||
|
|
/* Time to wait for workers to get preempted (seconds) */
|
||
|
|
#define PREEMPT_TIME 20
|
||
|
|
/*
|
||
|
|
* Factor by which to multiply number of online CPUs for total number of
|
||
|
|
* worker threads
|
||
|
|
*/
|
||
|
|
#define THREAD_FACTOR 8
|
||
|
|
|
||
|
|
|
||
|
|
__thread double darray[] = {0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0,
|
||
|
|
1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0,
|
||
|
|
2.1};
|
||
|
|
|
||
|
|
int threads_starting;
|
||
|
|
int running;
|
||
|
|
|
||
|
|
extern void preempt_fpu(double *darray, int *threads_starting, int *running);
|
||
|
|
|
||
|
|
void *preempt_fpu_c(void *p)
|
||
|
|
{
|
||
|
|
int i;
|
||
|
|
srand(pthread_self());
|
||
|
|
for (i = 0; i < 21; i++)
|
||
|
|
darray[i] = rand();
|
||
|
|
|
||
|
|
/* Test failed if it ever returns */
|
||
|
|
preempt_fpu(darray, &threads_starting, &running);
|
||
|
|
|
||
|
|
return p;
|
||
|
|
}
|
||
|
|
|
||
|
|
int test_preempt_fpu(void)
|
||
|
|
{
|
||
|
|
int i, rc, threads;
|
||
|
|
pthread_t *tids;
|
||
|
|
|
||
|
|
threads = sysconf(_SC_NPROCESSORS_ONLN) * THREAD_FACTOR;
|
||
|
|
tids = malloc((threads) * sizeof(pthread_t));
|
||
|
|
FAIL_IF(!tids);
|
||
|
|
|
||
|
|
running = true;
|
||
|
|
threads_starting = threads;
|
||
|
|
for (i = 0; i < threads; i++) {
|
||
|
|
rc = pthread_create(&tids[i], NULL, preempt_fpu_c, NULL);
|
||
|
|
FAIL_IF(rc);
|
||
|
|
}
|
||
|
|
|
||
|
|
setbuf(stdout, NULL);
|
||
|
|
/* Not really necessary but nice to wait for every thread to start */
|
||
|
|
printf("\tWaiting for all workers to start...");
|
||
|
|
while(threads_starting)
|
||
|
|
asm volatile("": : :"memory");
|
||
|
|
printf("done\n");
|
||
|
|
|
||
|
|
printf("\tWaiting for %d seconds to let some workers get preempted...", PREEMPT_TIME);
|
||
|
|
sleep(PREEMPT_TIME);
|
||
|
|
printf("done\n");
|
||
|
|
|
||
|
|
printf("\tStopping workers...");
|
||
|
|
/*
|
||
|
|
* Working are checking this value every loop. In preempt_fpu 'cmpwi r5,0; bne 2b'.
|
||
|
|
* r5 will have loaded the value of running.
|
||
|
|
*/
|
||
|
|
running = 0;
|
||
|
|
for (i = 0; i < threads; i++) {
|
||
|
|
void *rc_p;
|
||
|
|
pthread_join(tids[i], &rc_p);
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Harness will say the fail was here, look at why preempt_fpu
|
||
|
|
* returned
|
||
|
|
*/
|
||
|
|
if ((long) rc_p)
|
||
|
|
printf("oops\n");
|
||
|
|
FAIL_IF((long) rc_p);
|
||
|
|
}
|
||
|
|
printf("done\n");
|
||
|
|
|
||
|
|
free(tids);
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
int main(int argc, char *argv[])
|
||
|
|
{
|
||
|
|
return test_harness(test_preempt_fpu, "fpu_preempt");
|
||
|
|
}
|