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authorJosef Bacik <jbacik@redhat.com>2008-10-29 14:49:05 -0400
committerChris Mason <chris.mason@oracle.com>2008-10-29 14:49:05 -0400
commit2517920135b0d29e70453e5b03d70d7b94207df3 (patch)
treee0c526faa5c2c7bc3add340e5b7e8df26924dca9 /fs/btrfs/free-space-cache.c
parent80eb234af09dbe6c97b2e3d60a13ec391e98fbba (diff)
Btrfs: nuke fs wide allocation mutex V2
This patch removes the giant fs_info->alloc_mutex and replaces it with a bunch of little locks. There is now a pinned_mutex, which is used when messing with the pinned_extents extent io tree, and the extent_ins_mutex which is used with the pending_del and extent_ins extent io trees. The locking for the extent tree stuff was inspired by a patch that Yan Zheng wrote to fix a race condition, I cleaned it up some and changed the locking around a little bit, but the idea remains the same. Basically instead of holding the extent_ins_mutex throughout the processing of an extent on the extent_ins or pending_del trees, we just hold it while we're searching and when we clear the bits on those trees, and lock the extent for the duration of the operations on the extent. Also to keep from getting hung up waiting to lock an extent, I've added a try_lock_extent so if we cannot lock the extent, move on to the next one in the tree and we'll come back to that one. I have tested this heavily and it does not appear to break anything. This has to be applied on top of my find_free_extent redo patch. I tested this patch on top of Yan's space reblancing code and it worked fine. The only thing that has changed since the last version is I pulled out all my debugging stuff, apparently I forgot to run guilt refresh before I sent the last patch out. Thank you, Signed-off-by: Josef Bacik <jbacik@redhat.com>
Diffstat (limited to 'fs/btrfs/free-space-cache.c')
-rw-r--r--fs/btrfs/free-space-cache.c92
1 files changed, 66 insertions, 26 deletions
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index 96241f01fa0..f4926c0f3c8 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -184,8 +184,8 @@ static int link_free_space(struct btrfs_block_group_cache *block_group,
return ret;
}
-int btrfs_add_free_space(struct btrfs_block_group_cache *block_group,
- u64 offset, u64 bytes)
+static int __btrfs_add_free_space(struct btrfs_block_group_cache *block_group,
+ u64 offset, u64 bytes)
{
struct btrfs_free_space *right_info;
struct btrfs_free_space *left_info;
@@ -202,8 +202,6 @@ int btrfs_add_free_space(struct btrfs_block_group_cache *block_group,
* are adding, if there is remove that struct and add a new one to
* cover the entire range
*/
- spin_lock(&block_group->lock);
-
right_info = tree_search_offset(&block_group->free_space_offset,
offset+bytes, 0, 1);
left_info = tree_search_offset(&block_group->free_space_offset,
@@ -261,7 +259,6 @@ int btrfs_add_free_space(struct btrfs_block_group_cache *block_group,
if (ret)
kfree(info);
out:
- spin_unlock(&block_group->lock);
if (ret) {
printk(KERN_ERR "btrfs: unable to add free space :%d\n", ret);
if (ret == -EEXIST)
@@ -274,13 +271,13 @@ out:
return ret;
}
-int btrfs_remove_free_space(struct btrfs_block_group_cache *block_group,
- u64 offset, u64 bytes)
+static int
+__btrfs_remove_free_space(struct btrfs_block_group_cache *block_group,
+ u64 offset, u64 bytes)
{
struct btrfs_free_space *info;
int ret = 0;
- spin_lock(&block_group->lock);
info = tree_search_offset(&block_group->free_space_offset, offset, 0,
1);
@@ -334,17 +331,63 @@ int btrfs_remove_free_space(struct btrfs_block_group_cache *block_group,
/* step two, insert a new info struct to cover anything
* before the hole
*/
- spin_unlock(&block_group->lock);
- ret = btrfs_add_free_space(block_group, old_start,
- offset - old_start);
+ ret = __btrfs_add_free_space(block_group, old_start,
+ offset - old_start);
BUG_ON(ret);
- goto out_nolock;
} else {
WARN_ON(1);
}
out:
- spin_unlock(&block_group->lock);
-out_nolock:
+ return ret;
+}
+
+int btrfs_add_free_space(struct btrfs_block_group_cache *block_group,
+ u64 offset, u64 bytes)
+{
+ int ret;
+ struct btrfs_free_space *sp;
+
+ mutex_lock(&block_group->alloc_mutex);
+ ret = __btrfs_add_free_space(block_group, offset, bytes);
+ sp = tree_search_offset(&block_group->free_space_offset, offset, 0, 1);
+ BUG_ON(!sp);
+ mutex_unlock(&block_group->alloc_mutex);
+
+ return ret;
+}
+
+int btrfs_add_free_space_lock(struct btrfs_block_group_cache *block_group,
+ u64 offset, u64 bytes)
+{
+ int ret;
+ struct btrfs_free_space *sp;
+
+ ret = __btrfs_add_free_space(block_group, offset, bytes);
+ sp = tree_search_offset(&block_group->free_space_offset, offset, 0, 1);
+ BUG_ON(!sp);
+
+ return ret;
+}
+
+int btrfs_remove_free_space(struct btrfs_block_group_cache *block_group,
+ u64 offset, u64 bytes)
+{
+ int ret = 0;
+
+ mutex_lock(&block_group->alloc_mutex);
+ ret = __btrfs_remove_free_space(block_group, offset, bytes);
+ mutex_unlock(&block_group->alloc_mutex);
+
+ return ret;
+}
+
+int btrfs_remove_free_space_lock(struct btrfs_block_group_cache *block_group,
+ u64 offset, u64 bytes)
+{
+ int ret;
+
+ ret = __btrfs_remove_free_space(block_group, offset, bytes);
+
return ret;
}
@@ -386,18 +429,18 @@ void btrfs_remove_free_space_cache(struct btrfs_block_group_cache *block_group)
struct btrfs_free_space *info;
struct rb_node *node;
- spin_lock(&block_group->lock);
+ mutex_lock(&block_group->alloc_mutex);
while ((node = rb_last(&block_group->free_space_bytes)) != NULL) {
info = rb_entry(node, struct btrfs_free_space, bytes_index);
unlink_free_space(block_group, info);
kfree(info);
if (need_resched()) {
- spin_unlock(&block_group->lock);
+ mutex_unlock(&block_group->alloc_mutex);
cond_resched();
- spin_lock(&block_group->lock);
+ mutex_lock(&block_group->alloc_mutex);
}
}
- spin_unlock(&block_group->lock);
+ mutex_unlock(&block_group->alloc_mutex);
}
struct btrfs_free_space *btrfs_find_free_space_offset(struct
@@ -407,10 +450,10 @@ struct btrfs_free_space *btrfs_find_free_space_offset(struct
{
struct btrfs_free_space *ret;
- spin_lock(&block_group->lock);
+ mutex_lock(&block_group->alloc_mutex);
ret = tree_search_offset(&block_group->free_space_offset, offset,
bytes, 0);
- spin_unlock(&block_group->lock);
+ mutex_unlock(&block_group->alloc_mutex);
return ret;
}
@@ -422,10 +465,10 @@ struct btrfs_free_space *btrfs_find_free_space_bytes(struct
{
struct btrfs_free_space *ret;
- spin_lock(&block_group->lock);
+ mutex_lock(&block_group->alloc_mutex);
ret = tree_search_bytes(&block_group->free_space_bytes, offset, bytes);
- spin_unlock(&block_group->lock);
+ mutex_unlock(&block_group->alloc_mutex);
return ret;
}
@@ -434,16 +477,13 @@ struct btrfs_free_space *btrfs_find_free_space(struct btrfs_block_group_cache
*block_group, u64 offset,
u64 bytes)
{
- struct btrfs_free_space *ret;
+ struct btrfs_free_space *ret = NULL;
- spin_lock(&block_group->lock);
ret = tree_search_offset(&block_group->free_space_offset, offset,
bytes, 0);
if (!ret)
ret = tree_search_bytes(&block_group->free_space_bytes,
offset, bytes);
- spin_unlock(&block_group->lock);
-
return ret;
}