From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751641AbcFUVse (ORCPT ); Tue, 21 Jun 2016 17:48:34 -0400 Received: from mail-pf0-f169.google.com ([209.85.192.169]:34389 "EHLO mail-pf0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751381AbcFUVsb (ORCPT ); Tue, 21 Jun 2016 17:48:31 -0400 Date: Tue, 21 Jun 2016 14:47:54 -0700 (PDT) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Andrew Morton , Vlastimil Babka , Minchan Kim , Joonsoo Kim cc: Mel Gorman , Hugh Dickins , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [patch -mm 1/2] mm/compaction: split freepages without holding the zone lock fix Message-ID: User-Agent: Alpine 2.10 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If __isolate_free_page() fails, avoid adding to freelist so we don't call map_pages() with it. Signed-off-by: David Rientjes --- Fix for mm-compaction-split-freepages-without-holding-the-zone-lock.patch in -mm. mm/compaction.c | 29 +++++++++++++---------------- 1 file changed, 13 insertions(+), 16 deletions(-) diff --git a/mm/compaction.c b/mm/compaction.c --- a/mm/compaction.c +++ b/mm/compaction.c @@ -494,24 +494,21 @@ static unsigned long isolate_freepages_block(struct compact_control *cc, /* Found a free page, will break it into order-0 pages */ order = page_order(page); - isolated = __isolate_free_page(page, page_order(page)); + isolated = __isolate_free_page(page, order); + if (!isolated) + goto isolate_fail; set_page_private(page, order); total_isolated += isolated; list_add_tail(&page->lru, freelist); - - /* If a page was split, advance to the end of it */ - if (isolated) { - cc->nr_freepages += isolated; - if (!strict && - cc->nr_migratepages <= cc->nr_freepages) { - blockpfn += isolated; - break; - } - - blockpfn += isolated - 1; - cursor += isolated - 1; - continue; + cc->nr_freepages += isolated; + if (!strict && cc->nr_migratepages <= cc->nr_freepages) { + blockpfn += isolated; + break; } + /* Advance to end of split page */ + blockpfn += isolated - 1; + cursor += isolated - 1; + continue; isolate_fail: if (strict) @@ -622,7 +619,7 @@ isolate_freepages_range(struct compact_control *cc, */ } - /* split_free_page does not map the pages */ + /* __isolate_free_page() does not map the pages */ map_pages(&freelist); if (pfn < end_pfn) { @@ -1124,7 +1121,7 @@ static void isolate_freepages(struct compact_control *cc) } } - /* split_free_page does not map the pages */ + /* __isolate_free_page() does not map the pages */ map_pages(freelist); /* From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f200.google.com (mail-pf0-f200.google.com [209.85.192.200]) by kanga.kvack.org (Postfix) with ESMTP id E3159828E1 for ; Tue, 21 Jun 2016 17:47:56 -0400 (EDT) Received: by mail-pf0-f200.google.com with SMTP id e189so65901442pfa.2 for ; Tue, 21 Jun 2016 14:47:56 -0700 (PDT) Received: from mail-pf0-x233.google.com (mail-pf0-x233.google.com. [2607:f8b0:400e:c00::233]) by mx.google.com with ESMTPS id x2si42412611pfb.89.2016.06.21.14.47.56 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 21 Jun 2016 14:47:56 -0700 (PDT) Received: by mail-pf0-x233.google.com with SMTP id t190so10385637pfb.3 for ; Tue, 21 Jun 2016 14:47:56 -0700 (PDT) Date: Tue, 21 Jun 2016 14:47:54 -0700 (PDT) From: David Rientjes Subject: [patch -mm 1/2] mm/compaction: split freepages without holding the zone lock fix Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton , Vlastimil Babka , Minchan Kim , Joonsoo Kim Cc: Mel Gorman , Hugh Dickins , linux-kernel@vger.kernel.org, linux-mm@kvack.org If __isolate_free_page() fails, avoid adding to freelist so we don't call map_pages() with it. Signed-off-by: David Rientjes --- Fix for mm-compaction-split-freepages-without-holding-the-zone-lock.patch in -mm. mm/compaction.c | 29 +++++++++++++---------------- 1 file changed, 13 insertions(+), 16 deletions(-) diff --git a/mm/compaction.c b/mm/compaction.c --- a/mm/compaction.c +++ b/mm/compaction.c @@ -494,24 +494,21 @@ static unsigned long isolate_freepages_block(struct compact_control *cc, /* Found a free page, will break it into order-0 pages */ order = page_order(page); - isolated = __isolate_free_page(page, page_order(page)); + isolated = __isolate_free_page(page, order); + if (!isolated) + goto isolate_fail; set_page_private(page, order); total_isolated += isolated; list_add_tail(&page->lru, freelist); - - /* If a page was split, advance to the end of it */ - if (isolated) { - cc->nr_freepages += isolated; - if (!strict && - cc->nr_migratepages <= cc->nr_freepages) { - blockpfn += isolated; - break; - } - - blockpfn += isolated - 1; - cursor += isolated - 1; - continue; + cc->nr_freepages += isolated; + if (!strict && cc->nr_migratepages <= cc->nr_freepages) { + blockpfn += isolated; + break; } + /* Advance to end of split page */ + blockpfn += isolated - 1; + cursor += isolated - 1; + continue; isolate_fail: if (strict) @@ -622,7 +619,7 @@ isolate_freepages_range(struct compact_control *cc, */ } - /* split_free_page does not map the pages */ + /* __isolate_free_page() does not map the pages */ map_pages(&freelist); if (pfn < end_pfn) { @@ -1124,7 +1121,7 @@ static void isolate_freepages(struct compact_control *cc) } } - /* split_free_page does not map the pages */ + /* __isolate_free_page() does not map the pages */ map_pages(freelist); /* -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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