Re: [PATCH v2 7/7] sched/core: Add debug code to catch missing update_rq_clock()

From: Sergey Senozhatsky
Date: Wed Sep 21 2016 - 20:45:09 EST


Hello,

On (09/21/16 20:08), Matt Fleming wrote:
> On Wed, 21 Sep, at 05:58:27PM, Petr Mladek wrote:
> >
> > I am not sure how the above call chain is realistic. But adding
> > WARN_ON() into the scheduler paths is risky in general.
>
> It's not clear to me why this should be the case. WARN_ON() calls have
> existed in the scheduler paths since forever.
>
> If the new async printk patches make that impossible then surely they
> need fixing, not the scheduler?

it's not specific to async printk, because printk already invokes scheduler
via semaphore up().

-ss