Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756771AbZJ0UK1 (ORCPT ); Tue, 27 Oct 2009 16:10:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756724AbZJ0UK0 (ORCPT ); Tue, 27 Oct 2009 16:10:26 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:55212 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756739AbZJ0UKZ (ORCPT ); Tue, 27 Oct 2009 16:10:25 -0400 Date: Tue, 27 Oct 2009 13:09:24 -0700 From: Andrew Morton To: Mel Gorman Cc: stable@kernel.org, linux-kernel@vger.kernel.org, "linux-mm@kvack.org\"" , Frans Pop , Jiri Kosina , Sven Geggus , Karol Lewandowski , Tobias Oetiker , KOSAKI Motohiro , Pekka Enberg , Rik van Riel , Christoph Lameter , Stephan von Krawczynski , "Kernel Testers List , Mel Gorman "@linux-foundation.org Subject: Re: [PATCH 2/3] page allocator: Do not allow interrupts to use ALLOC_HARDER Message-Id: <20091027130924.fa903f5a.akpm@linux-foundation.org> In-Reply-To: <1256650833-15516-3-git-send-email-mel@csn.ul.ie> References: <1256650833-15516-1-git-send-email-mel@csn.ul.ie> <1256650833-15516-3-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: 1619 Lines: 42 On Tue, 27 Oct 2009 13:40:32 +0000 Mel Gorman wrote: > Commit 341ce06f69abfafa31b9468410a13dbd60e2b237 altered watermark logic > slightly by allowing rt_tasks that are handling an interrupt to set > ALLOC_HARDER. This patch brings the watermark logic more in line with > 2.6.30. > > [rientjes@google.com: Spotted the problem] > Signed-off-by: Mel Gorman > Reviewed-by: Pekka Enberg > Reviewed-by: Rik van Riel > Reviewed-by: KOSAKI Motohiro > --- > mm/page_alloc.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index dfa4362..7f2aa3e 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -1769,7 +1769,7 @@ gfp_to_alloc_flags(gfp_t gfp_mask) > * See also cpuset_zone_allowed() comment in kernel/cpuset.c. > */ > alloc_flags &= ~ALLOC_CPUSET; > - } else if (unlikely(rt_task(p))) > + } else if (unlikely(rt_task(p)) && !in_interrupt()) > alloc_flags |= ALLOC_HARDER; > > if (likely(!(gfp_mask & __GFP_NOMEMALLOC))) { What are the runtime-observeable effects of this change? The description is a bit waffly-sounding for a -stable backportable thing, IMO. What reason do the -stable maintainers and users have to believe that this patch is needed, and an improvement? -- 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/