[PATCH v4 0/3] mm: improvements in shrink slab

[Yafang Shao <laoar.shao@gmail.com>]

In the past few days, I found an issue in shrink slab.
We I was trying to fix it, I find there are something in shrink slab need
to be improved.

- #1 is to expose the min_slab_pages to help us analyze shrink slab.

- #2 is an code improvement.

- #3 is a fix to a issue. This issue is very easy to produce.
In the zone reclaim mode.
First you continuously cat a random non-exist file to produce
more and more dentry, then you read big file to produce page cache.
Finally you will find that the denty will never be shrunk.
In order to fix this issue, a new bitmask no_pagecache is introduce,
which is 0 by defalt.

Changes since v3:
A new bitmask no_pagecache is introduced in struct scan_control.

Yafang Shao (3):
  mm/vmstat: expose min_slab_pages in /proc/zoneinfo
  mm/vmscan: change return type of shrink_node() to void
  mm/vmscan: shrink slab in node reclaim

 mm/vmscan.c | 33 +++++++++++++++++++++++++++++----
 mm/vmstat.c |  8 ++++++++
 2 files changed, 37 insertions(+), 4 deletions(-)

-- 
1.8.3.1