[PATCH v2 0/3] zram: add rw_page implementation for zram and clean up unnecessary parameter

From: karam . lee
Date: Mon Oct 13 2014 - 04:55:58 EST


From: "karam.lee" <karam.lee@xxxxxxx>

Recently rw_page block device operation has been added.
This patchset implements rw_page operation for zram block device
and does some clean-up .

I implemented the feature in zram and tested it.
Test bed was the G2, LG electronic mobile device, whtich has msm8974
processor and 2GB memory.
With a memory allocation test program consuming memory, the system
generates swap.
And operating time of swap_write_page() was measured.

--------------------------------------------------
| | operating time | improvement |
| | (20 runs average) | |
--------------------------------------------------
|with patch | 1087.35 us | |
--------------------------------------------------
|without patch| 1061.15 us | +2.4% |
--------------------------------------------------

Each test(with paged_io,with BIO) result set shows normal distribution
and has equal variance.
I mean the two values are valid result to compare.
I can say operation with paged I/O(without BIO) is faster 2.4% with
confidence level 95%.

Patches 1~2 are for clean-up.
Patch 3 is for implementation of rw_page operation.
With the rw_page operation, zram can do I/O without allocating a BIO.
It make zram can save time and memory.

karam.lee (3):
zram: remove bio parameter from zram_bvec_rw().
zram: change parameter from vaild_io_request()
zram: implement rw_page operation of zram

drivers/block/zram/zram_drv.c | 69 +++++++++++++++++++++++++++++++----------
1 file changed, 53 insertions(+), 16 deletions(-)

--
1.7.9.5

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