Re: [PATCH RFC V2 2/5] stop_machine: make stop_machine safe andefficient to call early

From: Tejun Heo
Date: Sat Oct 01 2011 - 20:36:36 EST


On Sat, Oct 01, 2011 at 02:55:34PM -0700, Jeremy Fitzhardinge wrote:
> From: Jeremy Fitzhardinge <jeremy.fitzhardinge@xxxxxxxxxx>
> Make stop_machine() safe to call early in boot, before SMP has been
> set up, by simply calling the callback function directly if there's
> only one CPU online.

Maybe "before stop_machine is initialized" is better wording now both
here and in the comment?

> [ Fixes from AKPM:
> - add comment
> - local_irq_flags, not save_flags
> - also call hard_irq_disable() for systems which need it
> Tejun suggested using an explicit flag rather than just looking at
> the online cpu count. ]
> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@xxxxxxxxxx>
> Cc: Tejun Heo <tj@xxxxxxxxxx>
> Cc: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
> Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Cc: H. Peter Anvin <hpa@xxxxxxxxxxxxxxx>
> Cc: Ingo Molnar <mingo@xxxxxxx>
> Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>

Other than that,

Acked-by: Tejun Heo <tj@xxxxxxxxxx>


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