Commit 57f7c037 authored Dec 27, 2015 by Michael S. Tsirkin

asm-generic: guard smp_store_release/load_acquire



Allow architectures to override smp_store_release
and smp_load_acquire by guarding the defines
in asm-generic/barrier.h with ifndef directives.

This is in preparation to reusing asm-generic/barrier.h
on architectures which have their own definition
of these macros.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>

parent 5a1b26d7

include/asm-generic/barrier.h

+4 −0

Original line number	Diff line number	Diff line
		@@ -104,13 +104,16 @@
		#define smp_mb__after_atomic() smp_mb()
		#endif

		#ifndef smp_store_release
		#define smp_store_release(p, v) \
		do { \
		compiletime_assert_atomic_type(*p); \
		smp_mb(); \
		WRITE_ONCE(*p, v); \
		} while (0)
		#endif

		#ifndef smp_load_acquire
		#define smp_load_acquire(p) \
		({ \
		typeof(p) ___p1 = READ_ONCE(p); \
		@@ -118,6 +121,7 @@ do { \
		smp_mb(); \
		___p1; \
		})
		#endif

		#endif /* !__ASSEMBLY__ */
		#endif /* __ASM_GENERIC_BARRIER_H */