locking: Remove atomicy checks from {READ,WRITE}_ONCE
authorPeter Zijlstra <peterz@infradead.org>
Thu, 26 Mar 2015 16:45:37 +0000 (17:45 +0100)
committerIngo Molnar <mingo@kernel.org>
Fri, 27 Mar 2015 08:42:01 +0000 (09:42 +0100)
commit7bd3e239d6c6d1cad276e8f130b386df4234dcd7
tree260eb35894afb72ab32e860f37960b2dd6114e12
parente6beaa363d56d7fc2f8cd6f7291e4d93911a428a
locking: Remove atomicy checks from {READ,WRITE}_ONCE

The fact that volatile allows for atomic load/stores is a special case
not a requirement for {READ,WRITE}_ONCE(). Their primary purpose is to
force the compiler to emit load/stores _once_.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
include/linux/compiler.h