Btrfs: use a slab for the free space entries

Since we alloc/free free space entries a whole lot, lets use a slab to keep
track of them.  This makes some of my tests slightly faster.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index d97b69afbbfb..2d2e079713d7 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -50,6 +50,7 @@
 #include "tree-log.h"
 #include "compression.h"
 #include "locking.h"
+#include "free-space-cache.h"
 
 struct btrfs_iget_args {
         u64 ino;
@@ -70,6 +71,7 @@ static struct kmem_cache *btrfs_inode_cachep;
 struct kmem_cache *btrfs_trans_handle_cachep;
 struct kmem_cache *btrfs_transaction_cachep;
 struct kmem_cache *btrfs_path_cachep;
+struct kmem_cache *btrfs_free_space_cachep;
 
 #define S_SHIFT 12
 static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
@@ -6761,6 +6763,8 @@ void btrfs_destroy_cachep(void)
                 kmem_cache_destroy(btrfs_transaction_cachep);
         if (btrfs_path_cachep)
                 kmem_cache_destroy(btrfs_path_cachep);
+        if (btrfs_free_space_cachep)
+                kmem_cache_destroy(btrfs_free_space_cachep);
 }
 
 int btrfs_init_cachep(void)
@@ -6789,6 +6793,12 @@ int btrfs_init_cachep(void)
         if (!btrfs_path_cachep)
                 goto fail;
 
+        btrfs_free_space_cachep = kmem_cache_create("btrfs_free_space_cache",
+                        sizeof(struct btrfs_free_space), 0,
+                        SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
+        if (!btrfs_free_space_cachep)
+                goto fail;
+
         return 0;
 fail:
         btrfs_destroy_cachep();