Function cpus_fence_seq_cst

freebsd/kern/subr_smp.c:1038–1052

* Send an IPI forcing a sequentially consistent fence. * * Allows replacement of an explicitly fence with a compiler barrier. * Trades speed up during normal execution for a significant slowdown when * the barrier is needed. */

 * the barrier is needed.
 */
void
cpus_fence_seq_cst(void)
{

#ifdef SMP
	smp_rendezvous(
	    smp_no_rendezvous_barrier,
	    cpus_fence_seq_cst_issue,
	    smp_no_rendezvous_barrier,
	    NULL
	);
#else
	cpus_fence_seq_cst_issue(NULL);
#endif
}

/* Extra care is taken with this sysctl because the data type is volatile */
static int