Re: [PATCH 3/6] page-writeback: pass in '0' for nr_pages writeback in laptop mode

[Jan Kara]

On Tue 19-09-17 13:53:04, Jens Axboe wrote:
> Laptop mode really wants to writeback the number of dirty
> pages and inodes. Instead of calculating this in the caller,
> just pass in 0 and let wakeup_flusher_threads() handle it.
> 
> Use the new wakeup_flusher_threads_bdi() instead of rolling
> our own.
> 
> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
...
> -	rcu_read_lock();
> -	list_for_each_entry_rcu(wb, &q->backing_dev_info->wb_list, bdi_node)
> -		if (wb_has_dirty_io(wb))
> -			wb_start_writeback(wb, nr_pages, true,
> -					   WB_REASON_LAPTOP_TIMER);
> -	rcu_read_unlock();
> +	wakeup_flusher_threads_bdi(q->backing_dev_info, 0,
> +					WB_REASON_LAPTOP_TIMER);
>  }

So this slightly changes the semantics since previously we were doing
range_cyclic writeback and now we don't. I don't think this matters in
practice but please mention that in the changelog. With that you can add:

Reviewed-by: Jan Kara <jack@xxxxxxx>

								Honza
-- 
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR