Commit cd7f9699 authored by Nikolay Borisov's avatar Nikolay Borisov Committed by David Sterba
Browse files

btrfs: Open-code add_delayed_data_ref 



Now that the initialization part and the critical section code have been
split it's a lot easier to open code add_delayed_data_ref. Do so in the
following manner:

1. The common init function is put immediately after memory-to-be-initialized
   is allocated, followed by the specific data ref initialization.

2. The only piece of code that remains in the critical section is
   insert_delayed_ref call.

3. Tracing and memory freeing code is moved outside of the critical
   section.

No functional changes, just an overall shorter critical section.

Signed-off-by: default avatarNikolay Borisov <nborisov@suse.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 70d64000

fs/btrfs/delayed-ref.c

+22 −40
Original line number Diff line number Diff line
@@ -695,44 +695,6 @@ static void init_delayed_ref_common(struct btrfs_fs_info *fs_info, 
	INIT_LIST_HEAD(&ref->add_list);

}



/*

 * helper to insert a delayed data ref into the rbtree.

 */

static noinline void

add_delayed_data_ref(struct btrfs_trans_handle *trans,

		     struct btrfs_delayed_ref_head *head_ref,

		     struct btrfs_delayed_ref_node *ref, u64 bytenr,

		     u64 num_bytes, u64 parent, u64 ref_root, u64 owner,

		     u64 offset, int action)

{

	struct btrfs_delayed_data_ref *full_ref;

	struct btrfs_delayed_ref_root *delayed_refs;

	u8 ref_type;

	int ret;



	delayed_refs = &trans->transaction->delayed_refs;

	full_ref = btrfs_delayed_node_to_data_ref(ref);

	if (parent)

	        ref_type = BTRFS_SHARED_DATA_REF_KEY;

	else

	        ref_type = BTRFS_EXTENT_DATA_REF_KEY;



	init_delayed_ref_common(trans->fs_info, ref, bytenr, num_bytes,

				ref_root, action, ref_type);

	full_ref->root = ref_root;

	full_ref->parent = parent;

	full_ref->objectid = owner;

	full_ref->offset = offset;



	trace_add_delayed_data_ref(trans->fs_info, ref, full_ref,

				   action == BTRFS_ADD_DELAYED_EXTENT ?

				   BTRFS_ADD_DELAYED_REF : action);



	ret = insert_delayed_ref(trans, delayed_refs, head_ref, ref);

	if (ret > 0)

		kmem_cache_free(btrfs_delayed_data_ref_cachep, full_ref);

}



/*

 * add a delayed tree ref.  This does all of the accounting required

 * to make sure the delayed ref is eventually processed before this
@@ -832,11 +794,25 @@ int btrfs_add_delayed_data_ref(struct btrfs_fs_info *fs_info, 
	struct btrfs_delayed_ref_root *delayed_refs;

	struct btrfs_qgroup_extent_record *record = NULL;

	int qrecord_inserted;

	int ret;

	u8 ref_type;



	ref = kmem_cache_alloc(btrfs_delayed_data_ref_cachep, GFP_NOFS);

	if (!ref)

		return -ENOMEM;



	if (parent)

	        ref_type = BTRFS_SHARED_DATA_REF_KEY;

	else

	        ref_type = BTRFS_EXTENT_DATA_REF_KEY;

	init_delayed_ref_common(fs_info, &ref->node, bytenr, num_bytes,

				ref_root, action, ref_type);

	ref->root = ref_root;

	ref->parent = parent;

	ref->objectid = owner;

	ref->offset = offset;





	head_ref = kmem_cache_alloc(btrfs_delayed_ref_head_cachep, GFP_NOFS);

	if (!head_ref) {

		kmem_cache_free(btrfs_delayed_data_ref_cachep, ref);
@@ -868,10 +844,16 @@ int btrfs_add_delayed_data_ref(struct btrfs_fs_info *fs_info, 
					action, 1, 0, &qrecord_inserted,

					old_ref_mod, new_ref_mod);



	add_delayed_data_ref(trans, head_ref, &ref->node, bytenr, num_bytes,

			     parent, ref_root, owner, offset, action);

	ret = insert_delayed_ref(trans, delayed_refs, head_ref, &ref->node);

	spin_unlock(&delayed_refs->lock);



	trace_add_delayed_data_ref(trans->fs_info, &ref->node, ref,

				   action == BTRFS_ADD_DELAYED_EXTENT ?

				   BTRFS_ADD_DELAYED_REF : action);

	if (ret > 0)

		kmem_cache_free(btrfs_delayed_data_ref_cachep, ref);





	if (qrecord_inserted)

		return btrfs_qgroup_trace_extent_post(fs_info, record);

	return 0;

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