[PATCH 1/6] arm: Fix in-correct barrier usage in SWP{B} emulation

Punit Agrawal punit.agrawal at arm.com
Wed Aug 27 10:05:24 PDT 2014


Catalin Marinas <catalin.marinas at arm.com> writes:

> On Tue, Aug 26, 2014 at 11:28:45AM +0100, Punit Agrawal wrote:
>> According to the ARM ARMv7, explicit barriers are necessary when using
>> synchronisation primitives such as SWP{B}. The use of these
>> instructions does not automatically imply a barrier and any ordering
>> requirements by the software must be explicitly expressed with the use
>> of suitable barriers.
>> 
>> Based on this, remove the barriers from SWP{B} emulation.
>> 
>> Cc: Russell King <linux at arm.linux.org.uk>
>> Signed-off-by: Punit Agrawal <punit.agrawal at arm.com>
>
> This patch is independent to the SWP emulation for arm64 series. Unless
> Russell has any objections, you should send it to his patch system (git
> send-email to patches at arm.linux.org.uk with "KernelVersion: v3..." after
> the commit log; I hope Russell drops the KernelVersion requirement some
> day ;)).

OK. Unless I hear any objections, I'll send the patch to Russell's
system tomorrow.



More information about the linux-arm-kernel mailing list