Subject: Re: [PATCH 4/7] page-writeback: pass in '0' for nr_pages writeback in
 laptop mode
To: Christoph Hellwig <hch@infradead.org>
Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-mm@kvack.org, hannes@cmpxchg.org, clm@fb.com, jack@suse.cz
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 <20170921145929.GD8839@infradead.org>
From: Jens Axboe <axboe@kernel.dk>
Message-ID: <d0120f9e-9b52-9e42-7f1d-57e00ee12c3a@kernel.dk>
Date: Mon, 25 Sep 2017 08:57:52 -0600
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On 09/21/2017 08:59 AM, Christoph Hellwig wrote:
> On Wed, Sep 20, 2017 at 09:32:59AM -0600, 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. This changes the writeback to not be range cyclic,
>> but that should not matter for laptop mode flush-all
>> semantics.
> 
> Looks good,
> 
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> 
> While we're at sorting out the laptop_mode_wb_timer mess:
> can we move initializing and deleting it from the block code
> to the backing-dev code given that it now doesn't assume anything
> about block devices any more?

Good point, I'll include that in a followup for 4.15.

-- 
Jens Axboe