tree 6eef89a449f0256e5c9db04f36a562c5ff1c699d
parent 1aa2b3b7a6c4f3dbd3671171113a20e6a6190e3b
author Will Deacon <will.deacon@arm.com> 1370428046 +0100
committer Russell King <rmk+kernel@arm.linux.org.uk> 1371457624 +0100

ARM: 7749/1: spinlock: retry trylock operation if strex fails on free lock

An exclusive store instruction may fail for reasons other than lock
contention (e.g. a cache eviction during the critical section) so, in
line with other architectures using similar exclusive instructions
(alpha, mips, powerpc), retry the trylock operation if the lock appears
to be free but the strex reported failure.

Reported-by: Tony Thompson <anthony.thompson@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>