73bb8d9d92
When a child process is forked with OpenMP already initialized, the child process resets its affinity mask and sets proc-bind-var to false so that the entire original affinity mask is used. This patch corrects an issue with the affinity initialization code setting affinity to compact instead of none for this special case of forked children. The test trying to catch this only testing explicit setting of KMP_AFFINITY=none. Add test run for no KMP_AFFINITY setting. Fixes: #91098
103 lines
2.8 KiB
C
103 lines
2.8 KiB
C
// RUN: %libomp-compile
|
|
// RUN: %libomp-run
|
|
// RUN: env KMP_AFFINITY=none %libomp-run
|
|
// REQUIRES: linux
|
|
|
|
// Check if forked child process resets affinity properly by restricting
|
|
// child's affinity to a subset of the parent and then checking it after
|
|
// a parallel region
|
|
|
|
#define _GNU_SOURCE
|
|
#include "libomp_test_affinity.h"
|
|
#include <omp.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <sys/wait.h>
|
|
#include <sys/types.h>
|
|
#include <unistd.h>
|
|
|
|
// Set the affinity mask of the calling thread to a proper subset of the
|
|
// original affinity mask, specifically, one processor less.
|
|
void set_subset_affinity(affinity_mask_t *mask) {
|
|
int cpu;
|
|
affinity_mask_t *original_mask = affinity_mask_alloc();
|
|
affinity_mask_copy(original_mask, mask);
|
|
// Find first processor to clear for subset mask
|
|
for (cpu = 0; cpu <= AFFINITY_MAX_CPUS; ++cpu) {
|
|
if (affinity_mask_isset(original_mask, cpu)) {
|
|
affinity_mask_clr(mask, cpu);
|
|
break;
|
|
}
|
|
}
|
|
affinity_mask_free(original_mask);
|
|
set_thread_affinity(mask);
|
|
}
|
|
|
|
int main(int argc, char **argv) {
|
|
char buf[1024] = {0};
|
|
char *other_buf;
|
|
size_t n;
|
|
int child_exit_status, exit_status;
|
|
affinity_mask_t *mask = affinity_mask_alloc();
|
|
get_thread_affinity(mask);
|
|
n = affinity_mask_snprintf(buf, sizeof(buf), mask);
|
|
printf("Orignal Mask: %s\n", buf);
|
|
|
|
if (affinity_mask_count(mask) == 1) {
|
|
printf("Only one processor in affinity mask, skipping test.\n");
|
|
exit(EXIT_SUCCESS);
|
|
}
|
|
|
|
#pragma omp parallel
|
|
{
|
|
#pragma omp single
|
|
printf("Hello! Thread %d executed single region in parent process\n",
|
|
omp_get_thread_num());
|
|
}
|
|
|
|
pid_t pid = fork();
|
|
if (pid < 0) {
|
|
perror("fork()");
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
|
|
if (pid == 0) {
|
|
// Let child set a new initial mask
|
|
set_subset_affinity(mask);
|
|
#pragma omp parallel
|
|
{
|
|
#pragma omp single
|
|
printf("Hello! Thread %d executed single region in child process\n",
|
|
omp_get_thread_num());
|
|
}
|
|
affinity_mask_t *new_mask = affinity_mask_alloc();
|
|
get_thread_affinity(new_mask);
|
|
if (!affinity_mask_equal(mask, new_mask)) {
|
|
affinity_mask_snprintf(buf, sizeof(buf), mask);
|
|
fprintf(stderr, "Original Mask = %s\n", buf);
|
|
affinity_mask_snprintf(buf, sizeof(buf), new_mask);
|
|
fprintf(stderr, "New Mask = %s\n", buf);
|
|
affinity_mask_free(new_mask);
|
|
fprintf(stderr, "Child affinity mask did not reset properly\n");
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
affinity_mask_free(new_mask);
|
|
exit_status = EXIT_SUCCESS;
|
|
} else {
|
|
pid_t child_pid = pid;
|
|
pid = wait(&child_exit_status);
|
|
if (pid == -1) {
|
|
perror("wait()");
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
if (WIFEXITED(child_exit_status)) {
|
|
exit_status = WEXITSTATUS(child_exit_status);
|
|
} else {
|
|
exit_status = EXIT_FAILURE;
|
|
}
|
|
}
|
|
|
|
affinity_mask_free(mask);
|
|
return exit_status;
|
|
}
|