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Date: Sun, 28 Oct 2018 03:23:46 -0700
From: Matthew Wilcox <willy@infradead.org>
Subject: Re: [PATCH] mm: simplify get_next_ra_size
Message-ID: <20181028102346.GC25444@bombadil.infradead.org>
References: <1540707206-19649-1-git-send-email-hsiangkao@aol.com>
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Sender: owner-linux-mm@kvack.org
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To: Gao Xiang <hsiangkao@aol.com>
Cc: Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Fengguang Wu <fengguang.wu@intel.com>

On Sun, Oct 28, 2018 at 02:13:26PM +0800, Gao Xiang wrote:
> It's a trivial simplification for get_next_ra_size and
> clear enough for humans to understand.
> 
> It also fixes potential overflow if ra->size(< ra_pages) is too large.
> 
> Cc: Fengguang Wu <fengguang.wu@intel.com>
> Signed-off-by: Gao Xiang <hsiangkao@aol.com>

Reviewed-by: Matthew Wilcox <willy@infradead.org>

I also considered what would happen with underflow (passing a 'max'
less than 16, or less than 2) and it would seem to do the right thing
in that case.