Merge commit '9e9a928eed8796a0a1aaed7e0b676db86ba84594' into drm-next

Merge drm-fixes into drm-next.

Both i915 and radeon need this done for later patches.

Conflicts:
	drivers/gpu/drm/drm_crtc_helper.c
	drivers/gpu/drm/i915/i915_drv.h
	drivers/gpu/drm/i915/i915_gem.c
	drivers/gpu/drm/i915/i915_gem_execbuffer.c
	drivers/gpu/drm/i915/i915_gem_gtt.c

1 files changed, 18 insertions, 0 deletions

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 3f56c8deb3c0..32c661d66a45 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1916,6 +1916,24 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc,
 		get_lru_size(lruvec, LRU_INACTIVE_FILE);
 
 	/*
+	 * Prevent the reclaimer from falling into the cache trap: as
+	 * cache pages start out inactive, every cache fault will tip
+	 * the scan balance towards the file LRU.  And as the file LRU
+	 * shrinks, so does the window for rotation from references.
+	 * This means we have a runaway feedback loop where a tiny
+	 * thrashing file LRU becomes infinitely more attractive than
+	 * anon pages.  Try to detect this based on file LRU size.
+	 */
+	if (global_reclaim(sc)) {
+		unsigned long free = zone_page_state(zone, NR_FREE_PAGES);
+
+		if (unlikely(file + free <= high_wmark_pages(zone))) {
+			scan_balance = SCAN_ANON;
+			goto out;
+		}
+	}
+
+	/*
 	 * There is enough inactive page cache, do not reclaim
 	 * anything from the anonymous working set right now.
 	 */