[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Wed, 12 Dec 2012 17:34:56 -0500
From: Rik van Riel <riel@...hat.com>
To: Johannes Weiner <hannes@...xchg.org>
CC: Andrew Morton <akpm@...ux-foundation.org>,
Michal Hocko <mhocko@...e.cz>, Mel Gorman <mgorman@...e.de>,
Hugh Dickins <hughd@...gle.com>, linux-mm@...ck.org,
linux-kernel@...r.kernel.org
Subject: Re: [patch 8/8] mm: reduce rmap overhead for ex-KSM page copies created
on swap faults
On 12/12/2012 04:43 PM, Johannes Weiner wrote:
> When ex-KSM pages are faulted from swap cache, the fault handler is
> not capable of re-establishing anon_vma-spanning KSM pages. In this
> case, a copy of the page is created instead, just like during a COW
> break.
>
> These freshly made copies are known to be exclusive to the faulting
> VMA and there is no reason to go look for this page in parent and
> sibling processes during rmap operations.
>
> Use page_add_new_anon_rmap() for these copies. This also puts them on
> the proper LRU lists and marks them SwapBacked, so we can get rid of
> doing this ad-hoc in the KSM copy code.
>
> Signed-off-by: Johannes Weiner <hannes@...xchg.org>
Reviewed-by: Rik van Riel <riel@...hat.com>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists