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.Dd April 7, 2013
.Dt ck_pr_stall 3
.Sh NAME
.Nm ck_pr_stall
.Nd busy-wait primitive
.Sh LIBRARY
Concurrency Kit (libck, \-lck)
.Sh SYNOPSIS
.In ck_pr.h
.Ft void
.Fn ck_pr_stall void
.Sh DESCRIPTION
The
.Fn ck_pr_stall 3
function should be used inside retry paths of busy-wait loops.
It not only serves as a compiler barrier, but on some architectures
it emits cycle-saving instructions.
.Sh EXAMPLE
.Bd -literal -offset indent

#include <ck_pr.h>

static int ready = 0;

void
function(void)
{

	/* Busy-wait until ready is non-zero. */
	while (ck_pr_load_int(&ready) == 0)
		ck_pr_stall();

	return;
}
.Ed
.Sh SEE ALSO
.Xr ck_pr_fence_load 3 ,
.Xr ck_pr_fence_load_depends 3 ,
.Xr ck_pr_fence_store 3 ,
.Xr ck_pr_fence_memory 3 ,
.Xr ck_pr_barrier 3 ,
.Xr ck_pr_fas 3 ,
.Xr ck_pr_load 3 ,
.Xr ck_pr_store 3 ,
.Xr ck_pr_faa 3 ,
.Xr ck_pr_inc 3 ,
.Xr ck_pr_dec 3 ,
.Xr ck_pr_neg 3 ,
.Xr ck_pr_not 3 ,
.Xr ck_pr_add 3 ,
.Xr ck_pr_sub 3 ,
.Xr ck_pr_and 3 ,
.Xr ck_pr_or 3 ,
.Xr ck_pr_xor 3 ,
.Xr ck_pr_cas 3 ,
.Xr ck_pr_btc 3 ,
.Xr ck_pr_bts 3 ,
.Xr ck_pr_btr 3
.Pp
Additional information available at http://concurrencykit.org/