+ memcg-fix-zone-congestion.patch added to -mm tree

+ memcg-fix-zone-congestion.patch added to -mm tree

[akpm]

The patch titled
     memcg: fix zone congestion
has been added to the -mm tree.  Its filename is
     memcg-fix-zone-congestion.patch

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------------------------------------------------------
Subject: memcg: fix zone congestion
From: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>

ZONE_CONGESTED should be a state of global memory reclaim.  If not, a busy
memcg sets this and give unnecessary throttoling in wait_iff_congested()
against memory recalim in other contexts.  This makes system performance
bad.

I'll think about "memcg is congested!" flag is required or not, later. 
But this fix is required first.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Acked-by: Ying Han <yinghan@google.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/vmscan.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff -puN mm/vmscan.c~memcg-fix-zone-congestion mm/vmscan.c
--- a/mm/vmscan.c~memcg-fix-zone-congestion
+++ a/mm/vmscan.c
@@ -937,7 +937,8 @@ keep_lumpy:
 	 * back off and wait for congestion to clear because further reclaim
 	 * will encounter the same problem
 	 */
-	if (nr_dirty == nr_congested && nr_dirty != 0)
+	if (scanning_global_lru(sc) &&
+	    nr_dirty == nr_congested && nr_dirty != 0)
 		zone_set_flag(zone, ZONE_CONGESTED);
 
 	free_page_list(&free_pages);
_

Patches currently in -mm which might be from kamezawa.hiroyu@jp.fujitsu.com are

memcg-fix-zone-congestion.patch
memcg-fix-zone-congestion-fix.patch
mm-remove-unused-zone_idx-variable-from-set_migratetype_isolate.patch
mm-increase-reclaim_distance-to-30.patch
mm-introduce-wait_on_page_locked_killable.patch
x86mm-make-pagefault-killable.patch
mm-mem-hotplug-fix-section-mismatch-setup_per_zone_inactive_ratio-should-be-__meminit.patch
mm-mem-hotplug-recalculate-lowmem_reserve-when-memory-hotplug-occur.patch
mm-mem-hotplug-update-pcp-stat_threshold-when-memory-hotplug-occur.patch
mm-mem-hotplug-update-pcp-stat_threshold-when-memory-hotplug-occur-fix.patch
mm-convert-vma-vm_flags-to-64-bit.patch
mm-add-__nocast-attribute-to-vm_flags.patch
fremap-convert-vm_flags-to-unsigned-long-long.patch
procfs-convert-vm_flags-to-unsigned-long-long.patch
oom-replace-pf_oom_origin-with-toggling-oom_score_adj.patch
oom-replace-pf_oom_origin-with-toggling-oom_score_adj-update.patch
mm-mmu_gather-rework.patch
powerpc-mmu_gather-rework.patch
sparc-mmu_gather-rework.patch
s390-mmu_gather-rework.patch
arm-mmu_gather-rework.patch
sh-mmu_gather-rework.patch
ia64-mmu_gather-rework.patch
um-mmu_gather-rework.patch
mm-now-that-all-old-mmu_gather-code-is-gone-remove-the-storage.patch
mm-powerpc-move-the-rcu-page-table-freeing-into-generic-code.patch
mm-extended-batches-for-generic-mmu_gather.patch
lockdep-mutex-provide-mutex_lock_nest_lock.patch
mm-remove-i_mmap_lock-lockbreak.patch
mm-convert-i_mmap_lock-to-a-mutex.patch
mm-revert-page_lock_anon_vma-lock-annotation.patch
mm-improve-page_lock_anon_vma-comment.patch
mm-use-refcounts-for-page_lock_anon_vma.patch
mm-convert-anon_vma-lock-to-a-mutex.patch
mm-optimize-page_lock_anon_vma-fast-path.patch
mem-hotplug-call-isolate_lru_page-with-elevated-refcount.patch
mem-hwpoison-fix-page-refcount-around-isolate_lru_page.patch
mm-strictly-require-elevated-page-refcount-in-isolate_lru_page.patch
vmscan-change-shrink_slab-interfaces-by-passing-shrink_control.patch
vmscan-change-shrink_slab-interfaces-by-passing-shrink_control-fix.patch
vmscan-change-shrink_slab-interfaces-by-passing-shrink_control-fix-2.patch
vmscan-change-shrinker-api-by-passing-shrink_control-struct.patch
vmscan-change-shrinker-api-by-passing-shrink_control-struct-fix.patch
vmscan-change-shrinker-api-by-passing-shrink_control-struct-fix-2.patch
mm-fail-gfp_dma-allocations-when-zone_dma-is-not-configured.patch
mm-delete-non-atomic-mm-counter-implementation.patch
mm-move-enum-vm_event_item-into-a-standalone-header-file.patch
memcg-count-the-soft_limit-reclaim-in-global-background-reclaim.patch
memcg-add-the-soft_limit-reclaim-in-global-direct-reclaim.patch
memcg-add-stats-to-monitor-soft_limit-reclaim.patch
memcg-add-stats-to-monitor-soft_limit-reclaim-v2.patch
memcg-add-stats-to-monitor-soft_limit-reclaim-v2-fix.patch
memcg-add-stats-to-monitor-soft_limit-reclaim-v2-fix-2.patch
add-the-pagefault-count-into-memcg-stats.patch
add-the-pagefault-count-into-memcg-stats-fix.patch
memcg-remove-pointless-next_mz-nullification-in-mem_cgroup_soft_limit_reclaim.patch
memcg-mark-init_section_page_cgroup-properly.patch
memcg-fix-off-by-one-when-calculating-swap-cgroup-map-length.patch
memcg-move-page-freeing-code-out-of-lock.patch
maintainers-add-mm-page_cgroupc-into-memcg-subsystem.patch
memcg-reclaim-memory-from-nodes-in-round-robin-order.patch
memcg-reclaim-memory-from-nodes-in-round-robin-fix.patch
memcg-reclaim-memory-from-nodes-in-round-robin-fix-2.patch
memcg-fix-get_scan_count-for-small-targets.patch