[PATCH 0/3] zsmalloc: small compaction improvements

[Sergey Senozhatsky <sergey.senozhatsky@gmail.com>]

Hello,

First two patches introduce new zsmalloc zs_pages_to_compact()
symbol and change zram's `compact' sysfs attribute to be
read-write:
-- write triggers compaction, no changes
-- read returns the number of pages that compaction can
   potentially free

This lets user space to make a bit better decisions and to
avoid unneeded (which will not result in any significant
memory savings) compaction calls:

Example:

      if [ `cat /sys/block/zram<id>/compact` -gt 10 ]; then
          echo 1 > /sys/block/zram<id>/compact;
      fi

Up until now user space could not tell whether compaction
will result in any gain.

The third patch removes class locking around zs_can_compact()
in zs_pages_to_compact(), the motivation and details are
provided in the commit message.

Sergey Senozhatsky (3):
  zsmalloc: factor out zs_pages_to_compact()
  zram: make compact a read-write sysfs node
  zsmalloc: do not take class lock in zs_pages_to_compact()

 Documentation/ABI/testing/sysfs-block-zram |  7 +++---
 Documentation/blockdev/zram.txt            |  4 +++-
 drivers/block/zram/zram_drv.c              | 16 ++++++++++++-
 include/linux/zsmalloc.h                   |  1 +
 mm/zsmalloc.c                              | 37 +++++++++++++++++-------------
 5 files changed, 44 insertions(+), 21 deletions(-)

-- 
2.4.5