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Subject: Re: [PATCH v3 3/7] mm/lru: replace pgdat lru_lock with lruvec lock
To:     Matthew Wilcox <willy@infradead.org>
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From:   Alex Shi <alex.shi@linux.alibaba.com>
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Date:   Mon, 18 Nov 2019 20:31:50 +0800
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在 2019/11/18 下午8:14, Matthew Wilcox 写道:
>> Hi Matthew,
>>
>> Thanks for comments!
>>
>> Here, the irqflags is bound, and belong to lruvec, merging them into together helps us to take them as whole, and thus reduce a unnecessary code clues.
> It's not bound to the lruvec, though.  Call chain A uses it and call chain
> B doesn't.  If it was always used by every call chain, I'd see your point,
> but we have call chains which don't use it, and so it adds complexity.

Where is the call chain B, please?

> 
>> As your concern for a 'new' caller, since __split_huge_page is a static helper here, no distub for anyothers.
> Even though it's static, there may be other callers within the same file.
> Or somebody may decide to make it non-static in the future.  I think it's
> actually clearer to keep the irqflags as a separate parameter.
> 

But it's no one else using this function now. and no one get disturb, right? It's non sense to consider a 'possibility' issue.