]> nv-tegra.nvidia Code Review - linux-2.6.git/commit
percpu_counter: FBC_BATCH should be a variable
authorEric Dumazet <dada1@cosmosbay.com>
Tue, 6 Jan 2009 22:41:04 +0000 (14:41 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Tue, 6 Jan 2009 23:59:13 +0000 (15:59 -0800)
commit179f7ebff6be45738c6e2fa68c8d2cc5c2c6308e
tree3d48b5f825cfa29f5b39656503c5157872454e9f
parente3d5a27d5862b6425d0879272e24abecf7245105
percpu_counter: FBC_BATCH should be a variable

For NR_CPUS >= 16 values, FBC_BATCH is 2*NR_CPUS

Considering more and more distros are using high NR_CPUS values, it makes
sense to use a more sensible value for FBC_BATCH, and get rid of NR_CPUS.

A sensible value is 2*num_online_cpus(), with a minimum value of 32 (This
minimum value helps branch prediction in __percpu_counter_add())

We already have a hotcpu notifier, so we can adjust FBC_BATCH dynamically.

We rename FBC_BATCH to percpu_counter_batch since its not a constant
anymore.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/ext4/ext4.h
fs/ext4/inode.c
include/linux/percpu_counter.h
lib/percpu_counter.c