summaryrefslogtreecommitdiffstats
path: root/fs/btrfs/extent_map.c
diff options
context:
space:
mode:
authorChris Mason <chris.mason@oracle.com>2009-09-02 16:24:52 -0400
committerChris Mason <chris.mason@oracle.com>2009-09-11 13:31:05 -0400
commit890871be854b5f5e43e7ba2475f706209906cc24 (patch)
tree9d087adf7a28bb910992d07d93ea2a992e394110 /fs/btrfs/extent_map.c
parent57fd5a5ff8b48b99e90b22fc143082aba755c6c0 (diff)
downloadlinux-890871be854b5f5e43e7ba2475f706209906cc24.tar.gz
linux-890871be854b5f5e43e7ba2475f706209906cc24.tar.bz2
linux-890871be854b5f5e43e7ba2475f706209906cc24.zip
Btrfs: switch extent_map to a rw lock
There are two main users of the extent_map tree. The first is regular file inodes, where it is evenly spread between readers and writers. The second is the chunk allocation tree, which maps blocks from logical addresses to phyiscal ones, and it is 99.99% reads. The mapping tree is a point of lock contention during heavy IO workloads, so this commit switches things to a rw lock. Signed-off-by: Chris Mason <chris.mason@oracle.com>
Diffstat (limited to 'fs/btrfs/extent_map.c')
-rw-r--r--fs/btrfs/extent_map.c5
1 files changed, 1 insertions, 4 deletions
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 30c9365861e6..72e9fa3c31f5 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -36,7 +36,7 @@ void extent_map_exit(void)
void extent_map_tree_init(struct extent_map_tree *tree, gfp_t mask)
{
tree->map.rb_node = NULL;
- spin_lock_init(&tree->lock);
+ rwlock_init(&tree->lock);
}
/**
@@ -222,7 +222,6 @@ int add_extent_mapping(struct extent_map_tree *tree,
ret = -EEXIST;
goto out;
}
- assert_spin_locked(&tree->lock);
rb = tree_insert(&tree->map, em->start, &em->rb_node);
if (rb) {
ret = -EEXIST;
@@ -285,7 +284,6 @@ struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
struct rb_node *next = NULL;
u64 end = range_end(start, len);
- assert_spin_locked(&tree->lock);
rb_node = __tree_search(&tree->map, start, &prev, &next);
if (!rb_node && prev) {
em = rb_entry(prev, struct extent_map, rb_node);
@@ -331,7 +329,6 @@ int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em)
int ret = 0;
WARN_ON(test_bit(EXTENT_FLAG_PINNED, &em->flags));
- assert_spin_locked(&tree->lock);
rb_erase(&em->rb_node, &tree->map);
em->in_tree = 0;
return ret;