[patch v2 05/11] x86: Select ARCH_STORE_IMPLIES_RELEASE

[Thomas Gleixner <tglx@kernel.org>]

The generic unsafe_atomic_store_release_user() implementation does:

    if (!IS_ENABLED(CONFIG_ARCH_STORE_IMPLIES_RELEASE))
        smp_mb();
    unsafe_put_user();

As stores on x86 imply release, select ARCH_STORE_IMPLIES_RELEASE to avoid
the unnecessary smp_mb().

Signed-off-by: Thomas Gleixner <tglx@kernel.org>
---
V2: New patch
---
 arch/x86/Kconfig |    1 +
 1 file changed, 1 insertion(+)

--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -119,6 +119,7 @@ config X86
 	select ARCH_MIGHT_HAVE_PC_PARPORT
 	select ARCH_MIGHT_HAVE_PC_SERIO
 	select ARCH_STACKWALK
+	select ARCH_STORE_IMPLIES_RELEASE
 	select ARCH_SUPPORTS_ACPI
 	select ARCH_SUPPORTS_ATOMIC_RMW
 	select ARCH_SUPPORTS_DEBUG_PAGEALLOC