Messages in this thread | | | Date | Wed, 30 Mar 2011 15:41:40 +0200 (CEST) | From | Thomas Gleixner <> | Subject | Re: [PATCH] posix clocks: replace mutex with reader/writer semaphore |
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On Wed, 30 Mar 2011, Richard Cochran wrote:
> A dynamic posix clock is protected from asynchronous removal by a mutex. > However, using a mutex has the unwanted effect that a long running clock > operation in one process will unnecessarily block other processes. > > For example, one process might call read() to get an external time stamp > coming in at one pulse per second. A second process calling clock_gettime > would have to wait for almost a whole second. > > This patch fixes the issue by using a reader/writer semaphore instead of > a mutex.
Yuck. /me wonders why we did not see that during the review :)
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