On Nov 29, 2005, at 2:51 PM, Paul H. Hargrove wrote:
The result is the following, which I've tried in limited testing:
Holy Crimminey, Batman -- this message slipped by me in my INBOX.
This is friggen' amazing.
Many thanks, Paul!
enum {
SCHED_SETAFFINITY_TAKES_2_ARGS,
SCHED_SETAFFINITY_TAKES_3_ARGS_THIRD_IS_LONG,
SCHED_SETAFFINITY_TAKES_3_ARGS_THIRD_IS_CPU_SET,
SCHED_SETAFFINITY_UNKNOWN
};
/* We want to call by this prototype, even if it is not the real
one */
extern sched_setaffinity(int pid, unsigned int len, void *mask);
int probe_setaffinity(void) {
unsigned long mask[511];
int rc;
memset(mask, 0, sizeof(mask));
mask[0] = 1;
rc = sched_setaffinity(0, sizeof(mask), mask);
if (rc >= 0) {
/* Kernel truncates over-length masks -> successful call */
return SCHED_SETAFFINITY_TAKES_3_ARGS_THIRD_IS_CPU_SET;
} else if (errno == EINVAL) {
/* Kernel returns EINVAL when len != sizeof(long) */
return SCHED_SETAFFINITY_TAKES_3_ARGS_THIRD_IS_LONG;
} else if (errno == EFAULT) {
/* Kernel returns EFAULT having rejected len as an address */
return SCHED_SETAFFINITY_TAKES_2_ARGS;
}
return SCHED_SETAFFINITY_UNKNOWN;
};
--
{+} Jeff Squyres
{+} The Open MPI Project
{+} http://www.open-mpi.org/
