arm64: lockref: add support for lockless lockrefs using cmpxchg
authorWill Deacon <will.deacon@arm.com>
Wed, 9 Oct 2013 14:54:27 +0000 (15:54 +0100)
committerMark Brown <broonie@linaro.org>
Thu, 15 May 2014 19:00:54 +0000 (20:00 +0100)
commit9f89c68bf6d720eae561dc5a796f727a57e8daea
tree89da1c898f1ba5dd33ca33740d550a38b2a72b3d
parent5aa580e940c4ba9027b348729a53ee3cd4032cce
arm64: lockref: add support for lockless lockrefs using cmpxchg

Our spinlocks are only 32-bit (2x16-bit tickets) and our cmpxchg can
deal with 8-bytes (as one would hope!).

This patch wires up the cmpxchg-based lockless lockref implementation
for arm64.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 5686b06cea34e31ec0a549d9b5ac00776e8e8d6d)
Signed-off-by: Mark Brown <broonie@linaro.org>
arch/arm64/Kconfig
arch/arm64/include/asm/spinlock.h