summaryrefslogtreecommitdiffstats
path: root/fs/inode.c
diff options
context:
space:
mode:
authorEric Dumazet <dada1@cosmosbay.com>2006-03-26 01:37:24 -0800
committerLinus Torvalds <torvalds@g5.osdl.org>2006-03-26 08:56:56 -0800
commitfa3536cc144c1298f2ed9416c33f3b77fa2cd37a (patch)
tree5484541319b86ae7dac0def4db7925f7cc7008e7 /fs/inode.c
parent878a9f30d7b13015f3aa4534d7877d985f150183 (diff)
downloadop-kernel-dev-fa3536cc144c1298f2ed9416c33f3b77fa2cd37a.zip
op-kernel-dev-fa3536cc144c1298f2ed9416c33f3b77fa2cd37a.tar.gz
[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/inode.c')
-rw-r--r--fs/inode.c8
1 files changed, 4 insertions, 4 deletions
diff --git a/fs/inode.c b/fs/inode.c
index 85da110..1fddf28 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -56,8 +56,8 @@
#define I_HASHBITS i_hash_shift
#define I_HASHMASK i_hash_mask
-static unsigned int i_hash_mask;
-static unsigned int i_hash_shift;
+static unsigned int i_hash_mask __read_mostly;
+static unsigned int i_hash_shift __read_mostly;
/*
* Each inode can be on two separate lists. One is
@@ -73,7 +73,7 @@ static unsigned int i_hash_shift;
LIST_HEAD(inode_in_use);
LIST_HEAD(inode_unused);
-static struct hlist_head *inode_hashtable;
+static struct hlist_head *inode_hashtable __read_mostly;
/*
* A simple spinlock to protect the list manipulations.
@@ -98,7 +98,7 @@ static DEFINE_MUTEX(iprune_mutex);
*/
struct inodes_stat_t inodes_stat;
-static kmem_cache_t * inode_cachep;
+static kmem_cache_t * inode_cachep __read_mostly;
static struct inode *alloc_inode(struct super_block *sb)
{
OpenPOWER on IntegriCloud