diff options
author | Eric Dumazet <dada1@cosmosbay.com> | 2006-03-26 09:37:24 (GMT) |
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committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-03-26 16:56:56 (GMT) |
commit | fa3536cc144c1298f2ed9416c33f3b77fa2cd37a (patch) | |
tree | 5484541319b86ae7dac0def4db7925f7cc7008e7 /fs/bio.c | |
parent | 878a9f30d7b13015f3aa4534d7877d985f150183 (diff) | |
download | linux-fsl-qoriq-fa3536cc144c1298f2ed9416c33f3b77fa2cd37a.tar.xz |
[PATCH] Use __read_mostly on some hot fs variables
I discovered on oprofile hunting on a SMP platform that dentry lookups were
slowed down because d_hash_mask, d_hash_shift and dentry_hashtable were in
a cache line that contained inodes_stat. So each time inodes_stats is
changed by a cpu, other cpus have to refill their cache line.
This patch moves some variables to the __read_mostly section, in order to
avoid false sharing. RCU dentry lookups can go full speed.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'fs/bio.c')
-rw-r--r-- | fs/bio.c | 4 |
1 files changed, 2 insertions, 2 deletions
@@ -30,7 +30,7 @@ #define BIO_POOL_SIZE 256 -static kmem_cache_t *bio_slab; +static kmem_cache_t *bio_slab __read_mostly; #define BIOVEC_NR_POOLS 6 @@ -39,7 +39,7 @@ static kmem_cache_t *bio_slab; * basically we just need to survive */ #define BIO_SPLIT_ENTRIES 8 -mempool_t *bio_split_pool; +mempool_t *bio_split_pool __read_mostly; struct biovec_slab { int nr_vecs; |