[PATCH v2 02/32] asm-generic: guard smp_store_release/load_acquire
From: "Michael S. Tsirkin" <mst@redhat.com>
Date: 2015-12-31 19:16:11
Also in:
linux-arch, linux-arm-kernel, linux-mips, linux-s390, linux-sh, linux-um, lkml, sparclinux, virtualization
Subsystem:
generic include/asm header files, the rest · Maintainers:
Arnd Bergmann, Linus Torvalds
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> --- include/asm-generic/barrier.h | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/include/asm-generic/barrier.h b/include/asm-generic/barrier.h
index 0f45f93..987b2e0 100644
--- a/include/asm-generic/barrier.h
+++ b/include/asm-generic/barrier.h@@ -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 */
--
MST