Re: [PATCH 3/4] cputime: Consolidate vtime handling on contextswitch

[Martin Schwidefsky]

On Tue, 14 Aug 2012 16:16:49 +0200
Frederic Weisbecker <fweisbec@xxxxxxxxx> wrote:

> The archs that implement virtual cputime accounting all
> flush the cputime of a task when it gets descheduled
> and sometimes set up some ground initialization for the
> next task to account its cputime.
> 
> These archs all put their own hooks in their context
> switch callbacks and handle the off-case themselves.
> 
> Consolidate this by creating a new account_switch_vtime()
> callback called in generic code right after a context switch
> and that these archs must implement to flush the prev task
> cputime and initialize the next task cputime related state.

That change requires that the accounting for the previous process
can be done before finish_arch_switch() completed. With the old
code the architecture could to the accounting call in the middle
of finish_arch_switch, that is not possible anymore. Dunno if this
is relevant or not. For s390 the new code should work fine.

-- 
blue skies,
   Martin.

"Reality continues to ruin my life." - Calvin.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/