mm: cma: remove watermark hacks
Commits 2139cbe627b8 ("cma: fix counting of isolated pages") and
d95ea5d18e69 ("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 49f223a9cd96
("mm: trigger page reclaim in alloc_contig_range() to stabilise
watermarks") can be finally removed.
Change-Id: Iae17de8185eeabffd46752dbaf819591e6585869
CRs-Fixed: 480377
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Mel Gorman <mel@csn.ul.ie>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: bc357f431c836c6631751e3ef7dfe7882394ad67
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
[lauraa@codeaurora.org: Context fixup in mmzone.h, keep zone definition in
alloc_contig_range for other purposes]
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index ca7a586..d63232a 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -72,11 +72,9 @@
#ifdef CONFIG_CMA
bool is_cma_pageblock(struct page *page);
# define is_migrate_cma(migratetype) unlikely((migratetype) == MIGRATE_CMA)
-# define cma_wmark_pages(zone) zone->min_cma_pages
#else
# define is_cma_pageblock(page) false
# define is_migrate_cma(migratetype) false
-# define cma_wmark_pages(zone) 0
#endif
#define for_each_migratetype_order(order, type) \
@@ -385,11 +383,6 @@
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;
bool cma_alloc;
#endif
struct free_area free_area[MAX_ORDER];
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 69b9521..5ceccc7 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5199,10 +5199,6 @@
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);
}
@@ -5820,54 +5816,6 @@
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
@@ -5968,11 +5916,6 @@
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);