diff options
author | Will Deacon <will.deacon@arm.com> | 2012-08-13 17:38:48 +0000 |
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committer | Varun Colbert <vcolbert@nvidia.com> | 2012-09-10 14:29:19 -0700 |
commit | 75bdd482816eba85414a71b86535fa87db336aa3 (patch) | |
tree | 24d3861dd16b6a3440f655c359aef08db10f576e /virt | |
parent | c56d1413ee5fb5ae24f36e9e7b8e578f3d91db15 (diff) |
ARM: mutex: use generic atomic_dec-based implementation for ARMv6+
Commit a76d7bd96d65 ("ARM: 7467/1: mutex: use generic xchg-based
implementation for ARMv6+") removed the barrier-less, ARM-specific
mutex implementation in favour of the generic xchg-based code.
Since then, a bug was uncovered in the xchg code when running on SMP
platforms, due to interactions between the locking paths and the
MUTEX_SPIN_ON_OWNER code. This was fixed in 0bce9c46bf3b ("mutex: place
lock in contended state after fastpath_lock failure"), however, the
atomic_dec-based mutex algorithm is now marginally more efficient for
ARM (~0.5% improvement in hackbench scores on dual A15).
This patch moves ARMv6+ platforms to the atomic_dec-based mutex code.
Change-Id: I8f64e98ccb61cc1cb9cb68ee15e55d8a792792f5
Cc: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Reviewed-on: http://git-master/r/130941
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>
Tested-by: Bharat Nihalani <bnihalani@nvidia.com>
Diffstat (limited to 'virt')
0 files changed, 0 insertions, 0 deletions