Re: [RFC PATCH] introduce sys_membarrier(): process-wide memorybarrier

From: Mathieu Desnoyers
Date: Fri Jan 08 2010 - 18:53:46 EST


* Steven Rostedt (rostedt@xxxxxxxxxxx) wrote:
> Well, if we just grab the task_rq(task)->lock here, then we should be
> OK? We would guarantee that curr is either the task we want or not.
>

Hrm, I just tested it, and there seems to be a significant performance
penality involved with taking these locks for each CPU, even with just 8
cores. So if we can do without the locks, that would be preferred.

Thanks,

Mathieu

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Mathieu Desnoyers
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