Re: lib/58679: sched_getaffinity_np() always returns an empty set

[Christos Zoulas <christos%zoulas.com@localhost>]

Not really a bug.

christos

[10:10am] 26>cat getaffinity.c
#include <sched.h>
#include <unistd.h>
#include <err.h>
#include <stdio.h>

static int
cpu_count(cpuset_t *cpuset)
{
        int             rc;
        cpuid_t         i;

        rc = 0;
        for (i = 0;; i++) {
                int             r = cpuset_isset(i, cpuset);
                fprintf(stderr, "cpuset_isset(%d, %p) -> %d\n", (int)i, 
cpuset, r);
                if (r < 0)
                        break;
                if (r)
                        rc++;
        }

        return rc;
}


int
main(void)
{
        int             rc = -1;
        cpuset_t       *set = cpuset_create();
        if (set != NULL) {
                cpuset_set(0, set);
                if (-1 == sched_setaffinity_np(getpid(), 
cpuset_size(set), set))
                        err(1, "setaffinity");
                if (0 == sched_getaffinity_np(getpid(), 
cpuset_size(set), set))
                        rc = cpu_count(set);
                cpuset_destroy(set);
        }

        printf("Number of processors reported by sched_getaffinity_np: 
%d\n", rc);

        if (rc < 1)
                rc = sysconf(_SC_NPROCESSORS_ONLN);

        printf("Number of processors reported by 
sysconf(_SC_NPROCESSORS_ONLN): %d\n", rc);

        return 0;
}