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/**

 * smp_cond_acquire() - Spin wait for cond with ACQUIRE ordering

 * @cond: boolean expression to wait for

 *

 * Equivalent to using smp_load_acquire() on the condition variable but employs

 * the control dependency of the wait to reduce the barrier on many platforms.

 *

 * The control dependency provides a LOAD->STORE order, the additional RMB

 * provides LOAD->LOAD order, together they provide LOAD->{LOAD,STORE} order,

 * aka. ACQUIRE.

 */

#define smp_cond_acquire(cond)	do {		\

	while (!(cond))				\

		cpu_relax();			\

	smp_rmb(); /* ctrl + rmb := acquire */	\

} while (0)