staging: zram: remove special handle of uncompressed page
authorMinchan Kim <minchan@kernel.org>
Fri, 8 Jun 2012 06:39:27 +0000 (15:39 +0900)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Mon, 11 Jun 2012 16:00:01 +0000 (09:00 -0700)
commit130f315a174d127cbb90d4d1a4a7088dbcf930b5
treea7eb4d0c96be2773b57283b5230483474410d7e5
parent374a69191d12a0525b7ffe1197abc30c4795a230
staging: zram: remove special handle of uncompressed page

xvmalloc can't handle PAGE_SIZE page so that zram have to
handle it specially but zsmalloc can do it so let's remove
unnecessary special handling code.

Quote from Nitin
"I think page vs handle distinction was added since xvmalloc could not
handle full page allocation. Now that zsmalloc allows full page
allocation, we can just use it for both cases. This would also allow
removing the ZRAM_UNCOMPRESSED flag. The only downside will be slightly
slower code path for full page allocation but this event is anyways
supposed to be rare, so should be fine."

1. This patch reduces code very much.

 drivers/staging/zram/zram_drv.c   |  104 +++++--------------------------------
 drivers/staging/zram/zram_drv.h   |   17 +-----
 drivers/staging/zram/zram_sysfs.c |    6 +--
 3 files changed, 15 insertions(+), 112 deletions(-)

2. change pages_expand with bad_compress so it can count
   bad compression(above 75%) ratio.

3. remove zobj_header which is for back-reference for defragmentation
   because firstly, it's not used at the moment and zsmalloc can't handle
   bigger size than PAGE_SIZE so zram can't do it any more without redesign.

Cc: Seth Jennings <sjenning@linux.vnet.ibm.com>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Acked-by: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/staging/zram/zram_drv.c
drivers/staging/zram/zram_drv.h
drivers/staging/zram/zram_sysfs.c