From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755189AbaH1TIs (ORCPT ); Thu, 28 Aug 2014 15:08:48 -0400 Received: from cantor2.suse.de ([195.135.220.15]:32846 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752328AbaH1SgI (ORCPT ); Thu, 28 Aug 2014 14:36:08 -0400 From: Mel Gorman To: Jiri Slaby Cc: Linux-Stable , LKML , Mel Gorman Subject: [PATCH 20/97] mm: compaction: encapsulate defer reset logic Date: Thu, 28 Aug 2014 19:34:28 +0100 Message-Id: <1409250945-30874-21-git-send-email-mgorman@suse.de> X-Mailer: git-send-email 1.8.4.5 In-Reply-To: <1409250945-30874-1-git-send-email-mgorman@suse.de> References: <1409250945-30874-1-git-send-email-mgorman@suse.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Vlastimil Babka commit de6c60a6c115acaa721cfd499e028a413d1fcbf3 upstream. Currently there are several functions to manipulate the deferred compaction state variables. The remaining case where the variables are touched directly is when a successful allocation occurs in direct compaction, or is expected to be successful in the future by kswapd. Here, the lowest order that is expected to fail is updated, and in the case of successful allocation, the deferred status and counter is reset completely. Create a new function compaction_defer_reset() to encapsulate this functionality and make it easier to understand the code. No functional change. Signed-off-by: Vlastimil Babka Acked-by: Mel Gorman Reviewed-by: Rik van Riel Cc: Joonsoo Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Mel Gorman --- include/linux/compaction.h | 16 ++++++++++++++++ mm/compaction.c | 9 ++++----- mm/page_alloc.c | 5 +---- 3 files changed, 21 insertions(+), 9 deletions(-) diff --git a/include/linux/compaction.h b/include/linux/compaction.h index 091d72e..7e1c76e 100644 --- a/include/linux/compaction.h +++ b/include/linux/compaction.h @@ -62,6 +62,22 @@ static inline bool compaction_deferred(struct zone *zone, int order) return zone->compact_considered < defer_limit; } +/* + * Update defer tracking counters after successful compaction of given order, + * which means an allocation either succeeded (alloc_success == true) or is + * expected to succeed. + */ +static inline void compaction_defer_reset(struct zone *zone, int order, + bool alloc_success) +{ + if (alloc_success) { + zone->compact_considered = 0; + zone->compact_defer_shift = 0; + } + if (order >= zone->compact_order_failed) + zone->compact_order_failed = order + 1; +} + /* Returns true if restarting compaction after many failures */ static inline bool compaction_restarting(struct zone *zone, int order) { diff --git a/mm/compaction.c b/mm/compaction.c index d656656..c55bd45 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -1144,12 +1144,11 @@ static void __compact_pgdat(pg_data_t *pgdat, struct compact_control *cc) compact_zone(zone, cc); if (cc->order > 0) { - int ok = zone_watermark_ok(zone, cc->order, - low_wmark_pages(zone), 0, 0); - if (ok && cc->order >= zone->compact_order_failed) - zone->compact_order_failed = cc->order + 1; + if (zone_watermark_ok(zone, cc->order, + low_wmark_pages(zone), 0, 0)) + compaction_defer_reset(zone, cc->order, false); /* Currently async compaction is never deferred. */ - else if (!ok && cc->sync) + else if (cc->sync) defer_compaction(zone, cc->order); } diff --git a/mm/page_alloc.c b/mm/page_alloc.c index baef87e..3078eaf 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2251,10 +2251,7 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order, preferred_zone, migratetype); if (page) { preferred_zone->compact_blockskip_flush = false; - preferred_zone->compact_considered = 0; - preferred_zone->compact_defer_shift = 0; - if (order >= preferred_zone->compact_order_failed) - preferred_zone->compact_order_failed = order + 1; + compaction_defer_reset(preferred_zone, order, true); count_vm_event(COMPACTSUCCESS); return page; } -- 1.8.4.5