From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: Re: [PATCH 08/12] vmscan: Setup pagevec as late as possible in shrink_inactive_list() Date: Wed, 16 Jun 2010 16:43:09 -0700 Message-ID: <20100616164309.254b1a0d.akpm@linux-foundation.org> References: <1276514273-27693-1-git-send-email-mel@csn.ul.ie> <1276514273-27693-9-git-send-email-mel@csn.ul.ie> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Dave Chinner , Chris Mason , Nick Piggin , Rik van Riel , Johannes Weiner , Christoph Hellwig , KAMEZAWA Hiroyuki To: Mel Gorman Return-path: In-Reply-To: <1276514273-27693-9-git-send-email-mel@csn.ul.ie> Sender: owner-linux-mm@kvack.org List-Id: linux-fsdevel.vger.kernel.org On Mon, 14 Jun 2010 12:17:49 +0100 Mel Gorman wrote: > shrink_inactive_list() sets up a pagevec to release unfreeable pages. It > uses significant amounts of stack doing this. This patch splits > shrink_inactive_list() to take the stack usage out of the main path so > that callers to writepage() do not contain an unused pagevec on the > stack. You can get the entire pagevec off the stack - just make it a static-to-shrink_inactive_list() pagevec-per-cpu. Locking just requires pinning to a CPU. We could trivially co-opt shrink_inactive_list()'s spin_lock_irq() for that, but pagevec_release() can be relatively expensive so it'd be sad to move that inside spin_lock_irq(). It'd be better to slap a get_cpu()/put_cpu() around the whole thing. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org