Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757448Ab1DZGun (ORCPT ); Tue, 26 Apr 2011 02:50:43 -0400 Received: from fgwmail6.fujitsu.co.jp ([192.51.44.36]:42910 "EHLO fgwmail6.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757001Ab1DZGul (ORCPT ); Tue, 26 Apr 2011 02:50:41 -0400 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 From: KOSAKI Motohiro To: Wu Fengguang Subject: Re: readahead and oom Cc: kosaki.motohiro@jp.fujitsu.com, Dave Young , linux-mm , Linux Kernel Mailing List , Andrew Morton , Mel Gorman In-Reply-To: <20110426063421.GC19717@localhost> References: <20110426063421.GC19717@localhost> Message-Id: <20110426155258.F38F.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-Mailer: Becky! ver. 2.56.05 [ja] Date: Tue, 26 Apr 2011 15:50:39 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2121 Lines: 62 > > > btw readahead page allocations are completely optional. They are OK to > > > fail and in theory shall not trigger OOM on themselves. We may > > > consider passing __GFP_NORETRY for readahead page allocations. > > > > Good idea, care to submit a patch? > > Here it is :) > > Thanks, > Fengguang > --- > readahead: readahead page allocations is OK to fail > > Pass __GFP_NORETRY for readahead page allocations. > > readahead page allocations are completely optional. They are OK to > fail and in particular shall not trigger OOM on themselves. > > Reported-by: Dave Young > Signed-off-by: Wu Fengguang > --- > include/linux/pagemap.h | 5 +++++ > mm/readahead.c | 2 +- > 2 files changed, 6 insertions(+), 1 deletion(-) > > --- linux-next.orig/include/linux/pagemap.h 2011-04-26 14:27:46.000000000 +0800 > +++ linux-next/include/linux/pagemap.h 2011-04-26 14:29:31.000000000 +0800 > @@ -219,6 +219,11 @@ static inline struct page *page_cache_al > return __page_cache_alloc(mapping_gfp_mask(x)|__GFP_COLD); > } > > +static inline struct page *page_cache_alloc_cold_noretry(struct address_space *x) > +{ > + return __page_cache_alloc(mapping_gfp_mask(x)|__GFP_COLD|__GFP_NORETRY); > +} > + > typedef int filler_t(void *, struct page *); > > extern struct page * find_get_page(struct address_space *mapping, > --- linux-next.orig/mm/readahead.c 2011-04-26 14:27:02.000000000 +0800 > +++ linux-next/mm/readahead.c 2011-04-26 14:27:24.000000000 +0800 > @@ -180,7 +180,7 @@ __do_page_cache_readahead(struct address > if (page) > continue; > > - page = page_cache_alloc_cold(mapping); > + page = page_cache_alloc_cold_noretry(mapping); > if (!page) > break; > page->index = page_offset; I like this patch. Reviewed-by: KOSAKI Motohiro -- 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/