Btrfs: use slabs for auto defrag allocation

The auto defrag allocation is in the fast path of the IO, so use slabs
to improve the speed of the allocation.

And besides that, it can do check for leaked objects when the module is removed.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 91ff078e85dfaec25e818884e8420a780b23204a..389c05715eaacbb572f43e30421e4d9b37b32674 100644 (file)
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -3505,6 +3505,8 @@ void btrfs_get_block_group_info(struct list_head *groups_list,
                                struct btrfs_ioctl_space_info *space);
 
 /* file.c */
+int btrfs_auto_defrag_init(void);
+void btrfs_auto_defrag_exit(void);
 int btrfs_add_inode_defrag(struct btrfs_trans_handle *trans,
                           struct inode *inode);
 int btrfs_run_defrag_inodes(struct btrfs_fs_info *fs_info);

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index bd7f1b01e051f61afbd7456966b71b93fda45a99..15117eae85c4fc1c4cfc17acd59248d9f140b664 100644 (file)
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -41,6 +41,7 @@
 #include "compat.h"
 #include "volumes.h"
 
+static struct kmem_cache *btrfs_inode_defrag_cachep;
 /*
  * when auto defrag is enabled we
  * queue up these defrag structs to remember which
@@ -127,7 +128,7 @@ static void __btrfs_add_inode_defrag(struct inode *inode,
        return;
 
 exists:
-       kfree(defrag);
+       kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
        return;
 
 }
@@ -157,7 +158,7 @@ int btrfs_add_inode_defrag(struct btrfs_trans_handle *trans,
        else
                transid = BTRFS_I(inode)->root->last_trans;
 
-       defrag = kzalloc(sizeof(*defrag), GFP_NOFS);
+       defrag = kmem_cache_zalloc(btrfs_inode_defrag_cachep, GFP_NOFS);
        if (!defrag)
                return -ENOMEM;
 
@@ -169,7 +170,7 @@ int btrfs_add_inode_defrag(struct btrfs_trans_handle *trans,
        if (!test_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags))
                __btrfs_add_inode_defrag(inode, defrag);
        else
-               kfree(defrag);
+               kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
        spin_unlock(&root->fs_info->defrag_inodes_lock);
        return 0;
 }
@@ -315,7 +316,8 @@ int btrfs_run_defrag_inodes(struct btrfs_fs_info *fs_info)
 next:
                spin_lock(&fs_info->defrag_inodes_lock);
 next_free:
-               kfree(defrag);
+               if (defrag)
+                       kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
        }
        spin_unlock(&fs_info->defrag_inodes_lock);
 
@@ -2293,3 +2295,21 @@ const struct file_operations btrfs_file_operations = {
        .compat_ioctl   = btrfs_ioctl,
 #endif
 };
+
+void btrfs_auto_defrag_exit(void)
+{
+       if (btrfs_inode_defrag_cachep)
+               kmem_cache_destroy(btrfs_inode_defrag_cachep);
+}
+
+int btrfs_auto_defrag_init(void)
+{
+       btrfs_inode_defrag_cachep = kmem_cache_create("btrfs_inode_defrag",
+                                       sizeof(struct inode_defrag), 0,
+                                       SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
+                                       NULL);
+       if (!btrfs_inode_defrag_cachep)
+               return -ENOMEM;
+
+       return 0;
+}

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index def4f24b58df3be603bbcc3d2b0a1d8f7e21dfe6..99545df1b86c18071fed0cbf68dcbb8e745d5524 100644 (file)
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -1680,10 +1680,14 @@ static int __init init_btrfs_fs(void)
        if (err)
                goto free_ordered_data;
 
-       err = btrfs_interface_init();
+       err = btrfs_auto_defrag_init();
        if (err)
                goto free_delayed_inode;
 
+       err = btrfs_interface_init();
+       if (err)
+               goto free_auto_defrag;
+
        err = register_filesystem(&btrfs_fs_type);
        if (err)
                goto unregister_ioctl;
@@ -1695,6 +1699,8 @@ static int __init init_btrfs_fs(void)
 
 unregister_ioctl:
        btrfs_interface_exit();
+free_auto_defrag:
+       btrfs_auto_defrag_exit();
 free_delayed_inode:
        btrfs_delayed_inode_exit();
 free_ordered_data:
@@ -1714,6 +1720,7 @@ free_compress:
 static void __exit exit_btrfs_fs(void)
 {
        btrfs_destroy_cachep();
+       btrfs_auto_defrag_exit();
        btrfs_delayed_inode_exit();
        ordered_data_exit();
        extent_map_exit();