Re: [PATCH] mm, compaction: properly signal and act upon lock and need_sched() contention

David Rientjes
2014-05-12T20:28:19Z

On Mon, 12 May 2014, Vlastimil Babka wrote:

> diff --git a/mm/compaction.c b/mm/compaction.c
> index 83ca6f9..b34ab7c 100644
> --- a/mm/compaction.c
> +++ b/mm/compaction.c
> @@ -222,6 +222,27 @@ static bool compact_checklock_irqsave(spinlock_t *lock, unsigned long *flags,
> return true;
> }
>
> +/*
> + * Similar to compact_checklock_irqsave() (see its comment) for places where
> + * a zone lock is not concerned.
> + *
> + * Returns false when compaction should abort.
> + */

I think we should have some sufficient commentary in the code that
describes why we do this.

> +static inline bool compact_check_resched(struct compact_control *cc)
> +{

I'm not sure that compact_check_resched() is the appropriate name. Sure,
it specifies what the current implementation is, but what it's really
actually doing is determining when compaction should abort prematurely.

Something like compact_should_abort()?