From 872ca38f7afd9566bf2f88b95616f7ab71b50064 Mon Sep 17 00:00:00 2001 From: Marek Szyprowski Date: Fri, 9 Nov 2012 14:04:34 +1100 Subject: [PATCH] mm: cma: remove watermark hacks Commits 2139cbe627b89 ("cma: fix counting of isolated pages") and d95ea5d18e69951 ("cma: fix watermark checking") introduced a reliable method of free page accounting when memory is being allocated from CMA regions, so the workaround introduced earlier by commit 49f223a9cd96c72 ("mm: trigger page reclaim in alloc_contig_range() to stabilise watermarks") can be finally removed. Signed-off-by: Marek Szyprowski Cc: Kyungmin Park Cc: Arnd Bergmann Cc: Mel Gorman Acked-by: Michal Nazarewicz Cc: Minchan Kim Cc: Bartlomiej Zolnierkiewicz Signed-off-by: Andrew Morton --- include/linux/mmzone.h | 9 ------- mm/page_alloc.c | 57 ------------------------------------------ 2 files changed, 66 deletions(-) diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 7e116ede1547..d8737c181a4f 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -63,10 +63,8 @@ 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) \ @@ -372,13 +370,6 @@ struct zone { #ifdef CONFIG_MEMORY_HOTPLUG /* 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]; diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 43f48535bd37..6b990cb147b6 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5255,10 +5255,6 @@ static void __setup_per_zone_wmarks(void) zone->watermark[WMARK_LOW] = min_wmark_pages(zone) + (tmp >> 2); zone->watermark[WMARK_HIGH] = min_wmark_pages(zone) + (tmp >> 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); } @@ -5803,54 +5799,6 @@ static int __alloc_contig_migrate_range(struct compact_control *cc, 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; - - /* - * 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 */ - while (!zone_watermark_ok(zone, 0, low_wmark_pages(zone), 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, false); - } - } - - /* 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 @@ -5959,11 +5907,6 @@ 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(&cc, outer_start, end); -- 2.39.5