Re: [RFC PATCH v2 1/4] cpuidle: (powerpc) Add cpu_idle_wait() to allow switching of idle routines
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: 2011-11-29 07:04:20
Also in:
linuxppc-dev, lkml
Possibly related (same subject, not in this thread)
- 2011-11-28 · Re: [RFC PATCH v2 1/4] cpuidle: (powerpc) Add cpu_idle_wait() to allow switching of idle routines · Deepthi Dharwar <hidden>
- 2011-11-27 · Re: [RFC PATCH v2 1/4] cpuidle: (powerpc) Add cpu_idle_wait() to allow switching of idle routines · Benjamin Herrenschmidt <benh@kernel.crashing.org>
- 2011-11-17 · [RFC PATCH v2 1/4] cpuidle: (powerpc) Add cpu_idle_wait() to allow switching of idle routines · Deepthi Dharwar <hidden>
On Tue, 2011-11-29 at 12:12 +0530, Deepthi Dharwar wrote:
Yes, this could be problematic as there is small window for the race condition to occur . Otherwise we need to manually schedule it by running a kernel thread but this would definitely have a overhead and would be an overkill.
Depends what this "window" is. IE. What are you trying to protect yourself against ? What's the risk ? If it's just module unload, then stop_machine is probably your friend :-) Cheers, Ben.