Messages in this thread | | | Date | Mon, 21 Aug 2023 00:02:57 +0100 | From | Qais Yousef <> | Subject | Re: [PATCH 0/6] Backport rework of deadline bandwidth restoration for 5.10.y |
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On 08/20/23 12:24, Waiman Long wrote: > > On 8/20/23 11:21, Qais Yousef wrote: > > This is a backport of the series that fixes the way deadline bandwidth > > restoration is done which is causing noticeable delay on resume path. It also > > converts the cpuset lock back into a mutex which some users on Android too. > > I lack the details but AFAIU the read/write semaphore was slower on high > > contention. > > Note that it was a percpu rwsem before this patch series. It was not a > regular rwsem. Percpu rwsem isn't designed to handle high write lock > contention. A regular rwsem should be similar to mutex in performance when > handling high write lock contention.
Thanks a lot for the clarification Waiman! Much appreciated.
Cheers
-- Qais Yousef
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