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Sender: Tejun Heo <htejun@gmail.com>
Date: Mon, 3 Jun 2024 08:09:22 -1000
From: Tejun Heo <tj@kernel.org>
To: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: willy@infradead.org, akpm@linux-foundation.org,
	linux-fsdevel@vger.kernel.org, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 8/8] writeback: factor out balance_wb_limits to remove
 repeated code
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Hello,

On Mon, Jun 03, 2024 at 02:39:18PM +0800, Kemeng Shi wrote:
> > Isn't this a bit nasty? The helper skips updating states because it knows
> > the caller is not going to use them? I'm not sure the slight code reduction
> > justifies the added subtlety.
> 
> It's a general rule that wb should not be limited if the wb is in freerun state.
> So I think it's intuitive to obey the rule in both balance_wb_limits and it's
> caller in which case balance_wb_limits and it's caller should stop to do anything
> when freerun state of wb is first seen.
> But no insistant on this...

Hmm... can you at least add comments pointing out that if freerun, the
limits fields are invalid?

Thanks.

-- 
tejun