[PATCH V4 04/12] Btrfs: use a slab for ordered extents allocation
From: Miao Xie <hidden>
Date: 2012-09-06 10:44:51
Subsystem:
btrfs file system, filesystems (vfs and infrastructure), the rest · Maintainers:
Chris Mason, David Sterba, Alexander Viro, Christian Brauner, Linus Torvalds
The ordered extent allocation is in the fast path of the IO, so use a slab to improve the speed of the allocation. "Size of the struct is 280, so this will fall into the size-512 bucket, giving 8 objects per page, while own slab will pack 14 objects into a page. Another benefit I see is to check for leaked objects when the module is removed (and the cache destroy takes place)." -- David Sterba Signed-off-by: Miao Xie <redacted> --- Changelog v1 -> v4: - just change the changelog of this patch. --- fs/btrfs/ordered-data.c | 23 +++++++++++++++++++++-- fs/btrfs/ordered-data.h | 2 ++ fs/btrfs/super.c | 9 ++++++++- 3 files changed, 31 insertions(+), 3 deletions(-)
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index 2eb79cc..4ae1014 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c@@ -25,6 +25,8 @@ #include "btrfs_inode.h" #include "extent_io.h" +static struct kmem_cache *btrfs_ordered_extent_cache; + static u64 entry_end(struct btrfs_ordered_extent *entry) { if (entry->file_offset + entry->len < entry->file_offset)
@@ -187,7 +189,7 @@ static int __btrfs_add_ordered_extent(struct inode *inode, u64 file_offset, struct btrfs_ordered_extent *entry; tree = &BTRFS_I(inode)->ordered_tree; - entry = kzalloc(sizeof(*entry), GFP_NOFS); + entry = kmem_cache_zalloc(btrfs_ordered_extent_cache, GFP_NOFS); if (!entry) return -ENOMEM;
@@ -421,7 +423,7 @@ void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry) list_del(&sum->list); kfree(sum); } - kfree(entry); + kmem_cache_free(btrfs_ordered_extent_cache, entry); } }
@@ -958,3 +960,20 @@ void btrfs_add_ordered_operation(struct btrfs_trans_handle *trans, } spin_unlock(&root->fs_info->ordered_extent_lock); } + +int __init ordered_data_init(void) +{ + btrfs_ordered_extent_cache = kmem_cache_create("btrfs_ordered_extent", + sizeof(struct btrfs_ordered_extent), 0, + SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, + NULL); + if (!btrfs_ordered_extent_cache) + return -ENOMEM; + return 0; +} + +void ordered_data_exit(void) +{ + if (btrfs_ordered_extent_cache) + kmem_cache_destroy(btrfs_ordered_extent_cache); +}
diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h
index c2443a4..d1ddaef 100644
--- a/fs/btrfs/ordered-data.h
+++ b/fs/btrfs/ordered-data.h@@ -192,4 +192,6 @@ void btrfs_add_ordered_operation(struct btrfs_trans_handle *trans, struct inode *inode); void btrfs_wait_ordered_extents(struct btrfs_root *root, int nocow_only, int delay_iput); +int __init ordered_data_init(void); +void ordered_data_exit(void); #endif
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 073c236..48e53d6 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c@@ -1595,10 +1595,14 @@ static int __init init_btrfs_fs(void) if (err) goto free_extent_io; - err = btrfs_delayed_inode_init(); + err = ordered_data_init(); if (err) goto free_extent_map; + err = btrfs_delayed_inode_init(); + if (err) + goto free_ordered_data; + err = btrfs_interface_init(); if (err) goto free_delayed_inode;
@@ -1616,6 +1620,8 @@ unregister_ioctl: btrfs_interface_exit(); free_delayed_inode: btrfs_delayed_inode_exit(); +free_ordered_data: + ordered_data_exit(); free_extent_map: extent_map_exit(); free_extent_io:
@@ -1632,6 +1638,7 @@ static void __exit exit_btrfs_fs(void) { btrfs_destroy_cachep(); btrfs_delayed_inode_exit(); + ordered_data_exit(); extent_map_exit(); extent_io_exit(); btrfs_interface_exit();
--
1.7.6.5