]> err.no Git - linux-2.6/commit
[MTD] [NAND] subpage read feature as a way to increase performance.
authorAlexey Korolev <akorolev@infradead.org>
Thu, 15 May 2008 16:23:18 +0000 (17:23 +0100)
committerDavid Woodhouse <David.Woodhouse@intel.com>
Fri, 25 Jul 2008 14:49:50 +0000 (10:49 -0400)
commit3d45955962496879dead8d4dd70bb9a23b07154b
treeaf34201ba3bfc195a22ceac43a1c22f2f7c2fbe8
parentff877ea80efa2015b6263766f78ee42c2a1b32f9
[MTD] [NAND] subpage read feature as a way to increase performance.

This patch enables NAND subpage read functionality.
If upper layer drivers are requesting to read non page aligned data NAND
subpage-read functionality reads the only whose ECC regions which include
requested data when original code reads whole page.
This significantly improves performance in many cases.

Here are some digits :

UBI volume mount time
No subpage reads: 5.75 seconds
Subpage read patch: 2.42 seconds

Open/stat time for files on JFFS2 volume:
No subpage read  0m 5.36s
Subpage read     0m 2.88s

Signed-off-by Alexey Korolev <akorolev@infradead.org>
Acked-by: Artem Bityutskiy <dedekind@infradead.org>
Acked-by: Jörn Engel <joern@logfs.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
drivers/mtd/nand/nand_base.c
include/linux/mtd/nand.h