Commit 598865c5 authored by Will Deacon's avatar Will Deacon
Browse files

arm64: barrier: Implement smp_cond_load_relaxed 



We can provide an implementation of smp_cond_load_relaxed using READ_ONCE
and __cmpwait_relaxed.

Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
parent 76f4e2da

arch/arm64/include/asm/barrier.h

+13 −0
Original line number Diff line number Diff line
@@ -128,6 +128,19 @@ do { \ 
	__u.__val;							\

})



#define smp_cond_load_relaxed(ptr, cond_expr)				\

({									\

	typeof(ptr) __PTR = (ptr);					\

	typeof(*ptr) VAL;						\

	for (;;) {							\

		VAL = READ_ONCE(*__PTR);				\

		if (cond_expr)						\

			break;						\

		__cmpwait_relaxed(__PTR, VAL);				\

	}								\

	VAL;								\

})



#define smp_cond_load_acquire(ptr, cond_expr)				\

({									\

	typeof(ptr) __PTR = (ptr);					\