diff options
Diffstat (limited to 'fs/btrfs/delayed-ref.h')
| -rw-r--r-- | fs/btrfs/delayed-ref.h | 64 |
1 files changed, 41 insertions, 23 deletions
diff --git a/fs/btrfs/delayed-ref.h b/fs/btrfs/delayed-ref.h index 352921e76c74..611fb3388f82 100644 --- a/fs/btrfs/delayed-ref.h +++ b/fs/btrfs/delayed-ref.h @@ -61,7 +61,8 @@ struct btrfs_delayed_ref_node { /* * If action is BTRFS_ADD_DELAYED_REF, also link this node to * ref_head->ref_add_list, then we do not need to iterate the - * whole ref_head->ref_list to find BTRFS_ADD_DELAYED_REF nodes. + * refs rbtree in the corresponding delayed ref head + * (struct btrfs_delayed_ref_head::ref_tree). */ struct list_head add_list; @@ -123,12 +124,6 @@ struct btrfs_delayed_ref_head { u64 bytenr; u64 num_bytes; /* - * For insertion into struct btrfs_delayed_ref_root::href_root. - * Keep it in the same cache line as 'bytenr' for more efficient - * searches in the rbtree. - */ - struct rb_node href_node; - /* * the mutex is held while running the refs, and it is also * held when checking the sum of reference modifications. */ @@ -191,6 +186,11 @@ struct btrfs_delayed_ref_head { bool is_data; bool is_system; bool processing; + /* + * Indicate if it's currently in the data structure that tracks head + * refs (struct btrfs_delayed_ref_root::head_refs). + */ + bool tracked; }; enum btrfs_delayed_ref_flags { @@ -199,38 +199,52 @@ enum btrfs_delayed_ref_flags { }; struct btrfs_delayed_ref_root { - /* head ref rbtree */ - struct rb_root_cached href_root; - /* - * Track dirty extent records. + * Track head references. * The keys correspond to the logical address of the extent ("bytenr") * right shifted by fs_info->sectorsize_bits. This is both to get a more * dense index space (optimizes xarray structure) and because indexes in * xarrays are of "unsigned long" type, meaning they are 32 bits wide on * 32 bits platforms, limiting the extent range to 4G which is too low * and makes it unusable (truncated index values) on 32 bits platforms. + * Protected by the spinlock 'lock' defined below. */ - struct xarray dirty_extents; + struct xarray head_refs; - /* this spin lock protects the rbtree and the entries inside */ - spinlock_t lock; + /* + * Track dirty extent records. + * The keys correspond to the logical address of the extent ("bytenr") + * right shifted by fs_info->sectorsize_bits, for same reasons as above. + */ + struct xarray dirty_extents; - /* how many delayed ref updates we've queued, used by the - * throttling code + /* + * Protects the xarray head_refs, its entries and the following fields: + * num_heads, num_heads_ready, pending_csums and run_delayed_start. */ - atomic_t num_entries; + spinlock_t lock; - /* total number of head nodes in tree */ + /* Total number of head refs, protected by the spinlock 'lock'. */ unsigned long num_heads; - /* total number of head nodes ready for processing */ + /* + * Total number of head refs ready for processing, protected by the + * spinlock 'lock'. + */ unsigned long num_heads_ready; + /* + * Track space reserved for deleting csums of data extents. + * Protected by the spinlock 'lock'. + */ u64 pending_csums; unsigned long flags; + /* + * Track from which bytenr to start searching ref heads. + * Protected by the spinlock 'lock'. + */ u64 run_delayed_start; /* @@ -372,19 +386,22 @@ void btrfs_merge_delayed_refs(struct btrfs_fs_info *fs_info, struct btrfs_delayed_ref_head *head); struct btrfs_delayed_ref_head * -btrfs_find_delayed_ref_head(struct btrfs_delayed_ref_root *delayed_refs, +btrfs_find_delayed_ref_head(const struct btrfs_fs_info *fs_info, + struct btrfs_delayed_ref_root *delayed_refs, u64 bytenr); -int btrfs_delayed_ref_lock(struct btrfs_delayed_ref_root *delayed_refs, - struct btrfs_delayed_ref_head *head); static inline void btrfs_delayed_ref_unlock(struct btrfs_delayed_ref_head *head) { mutex_unlock(&head->mutex); } -void btrfs_delete_ref_head(struct btrfs_delayed_ref_root *delayed_refs, +void btrfs_delete_ref_head(const struct btrfs_fs_info *fs_info, + struct btrfs_delayed_ref_root *delayed_refs, struct btrfs_delayed_ref_head *head); struct btrfs_delayed_ref_head *btrfs_select_ref_head( + const struct btrfs_fs_info *fs_info, struct btrfs_delayed_ref_root *delayed_refs); +void btrfs_unselect_ref_head(struct btrfs_delayed_ref_root *delayed_refs, + struct btrfs_delayed_ref_head *head); int btrfs_check_delayed_seq(struct btrfs_fs_info *fs_info, u64 seq); @@ -399,6 +416,7 @@ int btrfs_delayed_refs_rsv_refill(struct btrfs_fs_info *fs_info, bool btrfs_check_space_for_delayed_refs(struct btrfs_fs_info *fs_info); bool btrfs_find_delayed_tree_ref(struct btrfs_delayed_ref_head *head, u64 root, u64 parent); +void btrfs_destroy_delayed_refs(struct btrfs_transaction *trans); static inline u64 btrfs_delayed_ref_owner(struct btrfs_delayed_ref_node *node) { |