The patch titled
Subject: mm/vmscan.c: add a new member reclaim_state in struct shrink_control
has been added to the -mm tree. Its filename is
mm-vmscan-add-a-new-member-reclaim_state-in-struct-shrink_control.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-vmscan-add-a-new-member-reclaim_state-in-struct-shrink_control.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-vmscan-add-a-new-member-reclaim_state-in-struct-shrink_control.patch
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------------------------------------------------------
From: Yafang Shao <laoar.shao@xxxxxxxxx>
Subject: mm/vmscan.c: add a new member reclaim_state in struct shrink_control
Patch series "mm/vmscan: calculate reclaimed slab in all reclaim paths".
This patchset is to fix the issues in doing shrink slab.
There're six different reclaim paths by now,
- kswapd reclaim path
- node reclaim path
- hibernate preallocate memory reclaim path
- direct reclaim path
- memcg reclaim path
- memcg softlimit reclaim path
The slab caches reclaimed in these paths are only calculated in the above
three paths. The issues are detailed explained in patch #2. We should
calculate the reclaimed slab caches in every reclaim path. In order to do
it, the struct reclaim_state is placed into the struct shrink_control.
In node reclaim path, there'is another issue about shrinking slab, which
is adressed in "mm/vmscan: shrink slab in node reclaim"
(https://lore.kernel.org/linux-mm/1559874946-22960-1-git-send-email-laoar.shao@xxxxxxxxx/).
This patch (of 2):
The struct reclaim_state is used to record how many slab caches are
reclaimed in one reclaim path. The struct shrink_control is used to
control one reclaim path. So we'd better put reclaim_state into
shrink_control.
Link: http://lkml.kernel.org/r/1561112086-6169-2-git-send-email-laoar.shao@xxxxxxxxx
Signed-off-by: Yafang Shao <laoar.shao@xxxxxxxxx>
Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Kirill Tkhai <ktkhai@xxxxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Vladimir Davydov <vdavydov.dev@xxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/vmscan.c | 20 ++++++++------------
1 file changed, 8 insertions(+), 12 deletions(-)
--- a/mm/vmscan.c~mm-vmscan-add-a-new-member-reclaim_state-in-struct-shrink_control
+++ a/mm/vmscan.c
@@ -131,6 +131,9 @@ struct scan_control {
unsigned int file_taken;
unsigned int taken;
} nr;
+
+ /* for recording the reclaimed slab by now */
+ struct reclaim_state reclaim_state;
};
#ifdef ARCH_HAS_PREFETCH
@@ -3491,6 +3494,7 @@ static int balance_pgdat(pg_data_t *pgda
.may_unmap = 1,
};
+ current->reclaim_state = &sc.reclaim_state;
psi_memstall_enter(&pflags);
__fs_reclaim_acquire();
@@ -3672,6 +3676,8 @@ out:
snapshot_refaults(NULL, pgdat);
__fs_reclaim_release();
psi_memstall_leave(&pflags);
+ current->reclaim_state = NULL;
+
/*
* Return the order kswapd stopped reclaiming at as
* prepare_kswapd_sleep() takes it into account. If another caller
@@ -3796,15 +3802,10 @@ static int kswapd(void *p)
unsigned int classzone_idx = MAX_NR_ZONES - 1;
pg_data_t *pgdat = (pg_data_t*)p;
struct task_struct *tsk = current;
-
- struct reclaim_state reclaim_state = {
- .reclaimed_slab = 0,
- };
const struct cpumask *cpumask = cpumask_of_node(pgdat->node_id);
if (!cpumask_empty(cpumask))
set_cpus_allowed_ptr(tsk, cpumask);
- current->reclaim_state = &reclaim_state;
/*
* Tell the memory management that we're a "memory allocator",
@@ -3866,7 +3867,6 @@ kswapd_try_sleep:
}
tsk->flags &= ~(PF_MEMALLOC | PF_SWAPWRITE | PF_KSWAPD);
- current->reclaim_state = NULL;
return 0;
}
@@ -3927,7 +3927,6 @@ void wakeup_kswapd(struct zone *zone, gf
*/
unsigned long shrink_all_memory(unsigned long nr_to_reclaim)
{
- struct reclaim_state reclaim_state;
struct scan_control sc = {
.nr_to_reclaim = nr_to_reclaim,
.gfp_mask = GFP_HIGHUSER_MOVABLE,
@@ -3945,8 +3944,7 @@ unsigned long shrink_all_memory(unsigned
fs_reclaim_acquire(sc.gfp_mask);
noreclaim_flag = memalloc_noreclaim_save();
- reclaim_state.reclaimed_slab = 0;
- p->reclaim_state = &reclaim_state;
+ p->reclaim_state = &sc.reclaim_state;
nr_reclaimed = do_try_to_free_pages(zonelist, &sc);
@@ -4115,7 +4113,6 @@ static int __node_reclaim(struct pglist_
/* Minimum pages needed in order to stay on node */
const unsigned long nr_pages = 1 << order;
struct task_struct *p = current;
- struct reclaim_state reclaim_state;
unsigned int noreclaim_flag;
struct scan_control sc = {
.nr_to_reclaim = max(nr_pages, SWAP_CLUSTER_MAX),
@@ -4140,8 +4137,7 @@ static int __node_reclaim(struct pglist_
*/
noreclaim_flag = memalloc_noreclaim_save();
p->flags |= PF_SWAPWRITE;
- reclaim_state.reclaimed_slab = 0;
- p->reclaim_state = &reclaim_state;
+ p->reclaim_state = &sc.reclaim_state;
if (node_pagecache_reclaimable(pgdat) > pgdat->min_unmapped_pages) {
/*
_
Patches currently in -mm which might be from laoar.shao@xxxxxxxxx are
mm-oom_kill-fix-uninitialized-oc-constraint.patch
mm-vmscan-expose-cgroup_ino-for-memcg-reclaim-tracepoints.patch
mm-vmscan-add-a-new-member-reclaim_state-in-struct-shrink_control.patch
mm-vmscan-calculate-reclaimed-slab-caches-in-all-reclaim-paths.patch
