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: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Nikolay Borisov 2018-04-24 17:18:21 +03:00 committed by David Sterba
parent 70d640004a
commit cd7f9699b1

View file

@ -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;