+ vmstat-reduce-time-interval-to-stat-update-on-idle-cpu.patch added to -mm tree

+ vmstat-reduce-time-interval-to-stat-update-on-idle-cpu.patch added to -mm tree

[akpm]

The patch titled
     Subject: vmstat: Reduce time interval to stat update on idle cpu
has been added to the -mm tree.  Its filename is
     vmstat-reduce-time-interval-to-stat-update-on-idle-cpu.patch

This patch should soon appear at
    http://ozlabs.org/~akpm/mmots/broken-out/vmstat-reduce-time-interval-to-stat-update-on-idle-cpu.patch
and later at
    http://ozlabs.org/~akpm/mmotm/broken-out/vmstat-reduce-time-interval-to-stat-update-on-idle-cpu.patch

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------------------------------------------------------
From: Christoph Lameter <cl@linux.com>
Subject: vmstat: Reduce time interval to stat update on idle cpu

It was noted that the vm stat shepherd runs every 2 seconds and that the
vmstat update is then scheduled 2 seconds in the future.

This yields an interval of double the time interval which is not desired.

Change the shepherd so that it does not delay the vmstat update on the
other cpu.  We stil have to use schedule_delayed_work since we are using a
delayed_work_struct but we can set the delay to 0.

Signed-off-by: Christoph Lameter <cl@linux.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vinayak Menon <vinmenon@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/vmstat.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff -puN mm/vmstat.c~vmstat-reduce-time-interval-to-stat-update-on-idle-cpu mm/vmstat.c
--- a/mm/vmstat.c~vmstat-reduce-time-interval-to-stat-update-on-idle-cpu
+++ a/mm/vmstat.c
@@ -1437,8 +1437,8 @@ static void vmstat_shepherd(struct work_
 		if (need_update(cpu) &&
 			cpumask_test_and_clear_cpu(cpu, cpu_stat_off))
 
-			schedule_delayed_work_on(cpu, &per_cpu(vmstat_work, cpu),
-				__round_jiffies_relative(sysctl_stat_interval, cpu));
+			schedule_delayed_work_on(cpu,
+				&per_cpu(vmstat_work, cpu), 0);
 
 	put_online_cpus();
 
_

Patches currently in -mm which might be from cl@linux.com are

mm-slub-optimize-alloc-free-fastpath-by-removing-preemption-on-off.patch
mm-slub-optimize-alloc-free-fastpath-by-removing-preemption-on-off-v3.patch
mm-dont-use-compound_head-in-virt_to_head_page.patch
mm-dont-use-compound_head-in-virt_to_head_page-v3.patch
mm-slub-fix-typo.patch
memcg-zap-memcg_slab_caches-and-memcg_slab_mutex.patch
mm-add-fields-for-compound-destructor-and-order-into-struct-page.patch
list_lru-introduce-list_lru_shrink_countwalk.patch
fs-consolidate-nrfree_cached_objects-args-in-shrink_control.patch
vmscan-per-memory-cgroup-slab-shrinkers.patch
memcg-rename-some-cache-id-related-variables.patch
memcg-add-rwsem-to-synchronize-against-memcg_caches-arrays-relocation.patch
list_lru-get-rid-of-active_nodes.patch
list_lru-organize-all-list_lrus-to-list.patch
list_lru-introduce-per-memcg-lists.patch
fs-make-shrinker-memcg-aware.patch
slab-embed-memcg_cache_params-to-kmem_cache.patch
slab-link-memcg-caches-of-the-same-kind-into-a-list.patch
cgroup-release-css-id-after-css_free.patch
slab-use-css-id-for-naming-per-memcg-caches.patch
memcg-free-memcg_caches-slot-on-css-offline.patch
list_lru-add-helpers-to-isolate-items.patch
memcg-reparent-list_lrus-and-free-kmemcg_id-on-css-offline.patch
slub-never-fail-to-shrink-cache.patch
slub-fix-kmem_cache_shrink-return-value.patch
slub-make-dead-caches-discard-free-slabs-immediately.patch
vmstat-do-not-use-deferrable-delayed-work-for-vmstat_update.patch
vmstat-reduce-time-interval-to-stat-update-on-idle-cpu.patch
mm-util-add-kstrdup_const.patch
kernfs-convert-node-name-allocation-to-kstrdup_const.patch
clk-convert-clock-name-allocations-to-kstrdup_const.patch
mm-slab-convert-cache-name-allocations-to-kstrdup_const.patch
mm-slab-convert-cache-name-allocations-to-kstrdup_const-fix.patch
fs-namespace-convert-devname-allocation-to-kstrdup_const.patch
cpumask-always-use-nr_cpu_ids-in-formatting-and-parsing-functions.patch
lib-vsprintf-implement-bitmap-printing-through-%pb.patch
cpumask-nodemask-implement-cpumask-nodemask_pr_args.patch
slub-use-%pb-to-print-bitmaps-including-cpumasks-and-nodemasks.patch
linux-next.patch