Re: [PATCH] stopmachine: add stopmachine_timeout v2

[Max Krasnyansky <maxk@qualcomm.com>]

Hidetoshi Seto wrote:
> Thank you for useful feedbacks!
> Here is the updated version.
> Could you put this on top of your patches, Rusty?
> 
> Thanks,
> H.Seto
> 
> 
> If stop_machine() invoked while one of onlined cpu is locked up
> by some reason, stop_machine cannot finish its work because the
> locked cpu cannot stop.  This means all other healthy cpus
> will be blocked infinitely by one dead cpu.
> 
> This patch allows stop_machine to return -EBUSY with some printk
> messages if any of stop_machine's threads cannot start running on
> its target cpu.
> 
> v2:
>  - remove fix for warning since it will be fixed upcoming typesafe
>    patches
>  - make stopmachine_timeout from secs to msecs, and set default to
>    200 msec (since v1's arbitrary 5 sec is too long)
>  - allow disabling timeout by setting the stopmachine_timeout to 0
> 

I'd set the default to zero. I beleive that's what Heiko suggested too.

Max