From 77e5849688670280b173bb9e0544e9da7b2acc36 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Sat, 14 Jan 2017 13:32:50 -0800 Subject: rcu: Make arch select smp_mb__after_unlock_lock() strength The definition of smp_mb__after_unlock_lock() is currently smp_mb() for CONFIG_PPC and a no-op otherwise. It would be better to instead provide an architecture-selectable Kconfig option, and select the strength of smp_mb__after_unlock_lock() based on that option. This commit therefore creates ARCH_WEAK_RELEASE_ACQUIRE, has PPC select it, and bases the definition of smp_mb__after_unlock_lock() on this new ARCH_WEAK_RELEASE_ACQUIRE Kconfig option. Reported-by: Ingo Molnar Signed-off-by: Paul E. McKenney Cc: Peter Zijlstra Cc: Will Deacon Cc: Boqun Feng Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Acked-by: Michael Ellerman Cc: Reviewed-by: Josh Triplett --- arch/Kconfig | 3 +++ 1 file changed, 3 insertions(+) (limited to 'arch/Kconfig') diff --git a/arch/Kconfig b/arch/Kconfig index cd211a14a88f..adefaf344239 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -320,6 +320,9 @@ config HAVE_CMPXCHG_LOCAL config HAVE_CMPXCHG_DOUBLE bool +config ARCH_WEAK_RELEASE_ACQUIRE + bool + config ARCH_WANT_IPC_PARSE_VERSION bool -- cgit v1.2.3