Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754280Ab2BVQtQ (ORCPT ); Wed, 22 Feb 2012 11:49:16 -0500 Received: from mailout2.w1.samsung.com ([210.118.77.12]:55254 "EHLO mailout2.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754177Ab2BVQtM (ORCPT ); Wed, 22 Feb 2012 11:49:12 -0500 Date: Wed, 22 Feb 2012 17:48:53 +0100 From: Marek Szyprowski Subject: [PATCHv23 12/16] mm: trigger page reclaim in alloc_contig_range() to stabilise watermarks In-reply-to: <1329929337-16648-1-git-send-email-m.szyprowski@samsung.com> To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org, linux-mm@kvack.org, linaro-mm-sig@lists.linaro.org Cc: Michal Nazarewicz , Marek Szyprowski , Kyungmin Park , Russell King , Andrew Morton , KAMEZAWA Hiroyuki , Daniel Walker , Mel Gorman , Arnd Bergmann , Jesse Barker , Jonathan Corbet , Chunsang Jeong , Dave Hansen , Benjamin Gaignard , Rob Clark , Ohad Ben-Cohen Message-id: <1329929337-16648-13-git-send-email-m.szyprowski@samsung.com> MIME-version: 1.0 X-Mailer: git-send-email 1.7.9 Content-type: TEXT/PLAIN Content-transfer-encoding: 7BIT References: <1329929337-16648-1-git-send-email-m.szyprowski@samsung.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4694 Lines: 142 alloc_contig_range() performs memory allocation so it also should keep track on keeping the correct level of memory watermarks. This commit adds a call to *_slowpath style reclaim to grab enough pages to make sure that the final collection of contiguous pages from freelists will not starve the system. Signed-off-by: Marek Szyprowski Signed-off-by: Kyungmin Park CC: Michal Nazarewicz Tested-by: Rob Clark Tested-by: Ohad Ben-Cohen Tested-by: Benjamin Gaignard Tested-by: Robert Nelson --- include/linux/mmzone.h | 9 +++++++ mm/page_alloc.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 71 insertions(+), 0 deletions(-) diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 4781f30..77db8c0 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -63,8 +63,10 @@ enum { #ifdef CONFIG_CMA # define is_migrate_cma(migratetype) unlikely((migratetype) == MIGRATE_CMA) +# define cma_wmark_pages(zone) zone->min_cma_pages #else # define is_migrate_cma(migratetype) false +# define cma_wmark_pages(zone) 0 #endif #define for_each_migratetype_order(order, type) \ @@ -371,6 +373,13 @@ struct zone { /* see spanned/present_pages for more description */ seqlock_t span_seqlock; #endif +#ifdef CONFIG_CMA + /* + * CMA needs to increase watermark levels during the allocation + * process to make sure that the system is not starved. + */ + unsigned long min_cma_pages; +#endif struct free_area free_area[MAX_ORDER]; #ifndef CONFIG_SPARSEMEM diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 7a0d286..39cd74f 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5092,6 +5092,11 @@ static void __setup_per_zone_wmarks(void) low + (min >> 2); zone->watermark[WMARK_HIGH] = min_wmark_pages(zone) + low + (min >> 1); + + zone->watermark[WMARK_MIN] += cma_wmark_pages(zone); + zone->watermark[WMARK_LOW] += cma_wmark_pages(zone); + zone->watermark[WMARK_HIGH] += cma_wmark_pages(zone); + setup_zone_migrate_reserve(zone); spin_unlock_irqrestore(&zone->lock, flags); } @@ -5695,6 +5700,56 @@ static int __alloc_contig_migrate_range(unsigned long start, unsigned long end) return ret > 0 ? 0 : ret; } +/* + * Update zone's cma pages counter used for watermark level calculation. + */ +static inline void __update_cma_watermarks(struct zone *zone, int count) +{ + unsigned long flags; + spin_lock_irqsave(&zone->lock, flags); + zone->min_cma_pages += count; + spin_unlock_irqrestore(&zone->lock, flags); + setup_per_zone_wmarks(); +} + +/* + * Trigger memory pressure bump to reclaim some pages in order to be able to + * allocate 'count' pages in single page units. Does similar work as + *__alloc_pages_slowpath() function. + */ +static int __reclaim_pages(struct zone *zone, gfp_t gfp_mask, int count) +{ + enum zone_type high_zoneidx = gfp_zone(gfp_mask); + struct zonelist *zonelist = node_zonelist(0, gfp_mask); + int did_some_progress = 0; + int order = 1; + unsigned long watermark; + + /* + * Increase level of watermarks to force kswapd do his job + * to stabilise at new watermark level. + */ + __update_cma_watermarks(zone, count); + + /* Obey watermarks as if the page was being allocated */ + watermark = low_wmark_pages(zone) + count; + while (!zone_watermark_ok(zone, 0, watermark, 0, 0)) { + wake_all_kswapd(order, zonelist, high_zoneidx, zone_idx(zone)); + + did_some_progress = __perform_reclaim(gfp_mask, order, zonelist, + NULL); + if (!did_some_progress) { + /* Exhausted what can be done so it's blamo time */ + out_of_memory(zonelist, gfp_mask, order, NULL); + } + } + + /* Restore original watermark levels. */ + __update_cma_watermarks(zone, -count); + + return count; +} + /** * alloc_contig_range() -- tries to allocate given range of pages * @start: start PFN to allocate @@ -5793,6 +5848,13 @@ int alloc_contig_range(unsigned long start, unsigned long end, goto done; } + /* + * Reclaim enough pages to make sure that contiguous allocation + * will not starve the system. + */ + __reclaim_pages(zone, GFP_HIGHUSER_MOVABLE, end-start); + + /* Grab isolated pages from freelists. */ outer_end = isolate_freepages_range(outer_start, end); if (!outer_end) { ret = -EBUSY; -- 1.7.1.569.g6f426 -- 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/