ext4: Remove useless spinlock in ext4_getattr()
authorTheodore Ts'o <tytso@mit.edu>
Tue, 2 Nov 2010 13:34:50 +0000 (09:34 -0400)
committerLinus Torvalds <torvalds@linux-foundation.org>
Tue, 2 Nov 2010 14:38:30 +0000 (10:38 -0400)
commiteb8abb927ae2fd1730e24ea94cd9527f3c086292
treee0ae72934040e8d840db503c311ac070d9850bc8
parent7fe19da4ca38fc20cdbc7020fcf2eca8fc756410
ext4: Remove useless spinlock in ext4_getattr()

Linus noted, and complained to me, that doing while lots of "git diff"'s
of kernel sources, these spinlocks were responsible for 27% of the
spinlock cost on his two-processor system as reported by perf.

Git was doing lots of parallel stats, and this was putting a lot of
pressure on ext4_getattr().  A spinlock to protect a single
memory-to-memory copy is pointless, so remove it.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/ext4/inode.c