Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759840Ab0FPXoa (ORCPT ); Wed, 16 Jun 2010 19:44:30 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:57392 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755556Ab0FPXo3 (ORCPT ); Wed, 16 Jun 2010 19:44:29 -0400 Date: Wed, 16 Jun 2010 16:43:09 -0700 From: Andrew Morton To: Mel Gorman 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 Subject: Re: [PATCH 08/12] vmscan: Setup pagevec as late as possible in shrink_inactive_list() Message-Id: <20100616164309.254b1a0d.akpm@linux-foundation.org> In-Reply-To: <1276514273-27693-9-git-send-email-mel@csn.ul.ie> References: <1276514273-27693-1-git-send-email-mel@csn.ul.ie> <1276514273-27693-9-git-send-email-mel@csn.ul.ie> X-Mailer: Sylpheed 2.4.8 (GTK+ 2.12.9; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1013 Lines: 23 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 from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/