Messages in this thread | | | Date | Tue, 14 Jul 2015 14:47:56 -0400 | From | Waiman Long <> | Subject | Re: [PATCH 5/7] locking/pvqspinlock: Add pending bit support |
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On 07/12/2015 04:21 AM, Peter Zijlstra wrote: > On Sat, Jul 11, 2015 at 04:36:56PM -0400, Waiman Long wrote: >> Like the native qspinlock, using the pending bit when it is lightly >> loaded to acquire the lock is faster than going through the PV queuing >> process which is even slower than the native queuing process. It also >> avoids loading two additional cachelines (the MCS and PV nodes). >> >> This patch adds the pending bit support for PV qspinlock. The >> pending bit code has a smaller spin threshold. It will default back >> to the queuing method if it cannot acquired the lock within a certain >> time limit. > -ENONUMBERS
Will send out an updated patchset with patch-to-patch performance numbers.
Cheers, Longman
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