From: Eric Sandeen <sandeen@redhat.com>
Date: Thu, 5 Aug 2010 05:46:37 +0000 (-0400)
Subject: ext4: re-inline ext4_rec_len_(to|from)_disk functions
X-Git-Tag: v2.6.36-rc1~501^2~2
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0cfc9255a1efb0467de2162950197750570ecec0;p=pandora-kernel.git

ext4: re-inline ext4_rec_len_(to|from)_disk functions

commit 3d0518f4, "ext4: New rec_len encoding for very
large blocksizes" made several changes to this path, but from
a perf perspective, un-inlining ext4_rec_len_from_disk() seems
most significant.  This function is called from ext4_check_dir_entry(),
which on a file-creation workload is called extremely often.

I tested this with bonnie:

# bonnie++ -u root -s 0 -f -x 200 -d /mnt/test -n 32

(this does 200 iterations) and got this for the file creations:

ext4 stock:   Average =  21206.8 files/s
ext4 inlined: Average =  22346.7 files/s  (+5%)

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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