Re: [patch 7/8] raid5: raid5d handle stripe in batch way

[Shaohua Li <shli@kernel.org>]

On Thu, Jun 07, 2012 at 11:32:39AM +1000, NeilBrown wrote:
> On Mon, 04 Jun 2012 16:01:59 +0800 Shaohua Li <shli@kernel.org> wrote:
> 
> > Let raid5d handle stripe in batch way to reduce conf->device_lock locking.
> > 
> > Signed-off-by: Shaohua Li <shli@fusionio.com>
> 
> I like this.
> I don't think it justifies a separate function.
> 
> #define MAX_STRIPE_BATCH 8
> struct stripe_head *batch[MAX_STRIPE_BATCH]
> int batch_size = 0;
> 
> ...
> 
> while (batch_size < MAX_STRPE_BATCH &&
>        (sh = __get_priority_stripe(conf)) != NULL)
>      batch[batch_size++] = sh;
> 
> spin_unlock(&conf->device_lock);
> if (batch_size == 0)
>      break;
> 
> handled += batch_size;
> 
> for (i = 0; i < batch_size; i++)
>      handle_stripe(batch[i]);
> cond_resched();
> if (....) md_check_recovery(mddev);
> 
> spin_lock_irq(&conf->lock);
> for (i = 0; i < batch_size; i++)
>      __release_stripe(batch[i]);
> 
> 
> something like that?

the 8th patch does the same thing, so I moved the code to a separate function.