From 96d89923fa9496280e3cd1d504058d99df79f22e Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Wed, 17 Aug 2022 12:22:40 +0100 Subject: [PATCH] btrfs: store index number instead of key in struct btrfs_delayed_item All delayed items are for dir index keys, so there's really no point of having an embedded struct btrfs_key in struct btrfs_delayed_item, which makes the structure use more space than necessary (and adds a hole of 7 bytes). So replace the key field with an index number (u64), which reduces the size of struct btrfs_delayed_item from 112 bytes down to 96 bytes. Some upcoming work will increase the structure size by 16 bytes, so this change compensates for that future size increase. Signed-off-by: Filipe Manana Signed-off-by: David Sterba --- fs/btrfs/delayed-inode.c | 106 ++++++++++++++++++++------------------- fs/btrfs/delayed-inode.h | 3 +- 2 files changed, 56 insertions(+), 53 deletions(-) diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c index a080e08bbb4d..cd2f3a8c4dfd 100644 --- a/fs/btrfs/delayed-inode.c +++ b/fs/btrfs/delayed-inode.c @@ -302,7 +302,8 @@ static inline void btrfs_release_prepared_delayed_node( __btrfs_release_delayed_node(node, 1); } -static struct btrfs_delayed_item *btrfs_alloc_delayed_item(u32 data_len) +static struct btrfs_delayed_item *btrfs_alloc_delayed_item(u32 data_len, + struct btrfs_delayed_node *node) { struct btrfs_delayed_item *item; item = kmalloc(sizeof(*item) + data_len, GFP_NOFS); @@ -310,7 +311,8 @@ static struct btrfs_delayed_item *btrfs_alloc_delayed_item(u32 data_len) item->data_len = data_len; item->ins_or_del = 0; item->bytes_reserved = 0; - item->delayed_node = NULL; + item->delayed_node = node; + RB_CLEAR_NODE(&item->rb_node); refcount_set(&item->refs, 1); } return item; @@ -319,7 +321,7 @@ static struct btrfs_delayed_item *btrfs_alloc_delayed_item(u32 data_len) /* * __btrfs_lookup_delayed_item - look up the delayed item by key * @delayed_node: pointer to the delayed node - * @key: the key to look up + * @index: the dir index value to lookup (offset of a dir index key) * @prev: used to store the prev item if the right item isn't found * @next: used to store the next item if the right item isn't found * @@ -328,7 +330,7 @@ static struct btrfs_delayed_item *btrfs_alloc_delayed_item(u32 data_len) */ static struct btrfs_delayed_item *__btrfs_lookup_delayed_item( struct rb_root *root, - struct btrfs_key *key, + u64 index, struct btrfs_delayed_item **prev, struct btrfs_delayed_item **next) { @@ -342,10 +344,9 @@ static struct btrfs_delayed_item *__btrfs_lookup_delayed_item( delayed_item = rb_entry(node, struct btrfs_delayed_item, rb_node); prev_node = node; - ret = btrfs_comp_cpu_keys(&delayed_item->key, key); - if (ret < 0) + if (delayed_item->index < index) node = node->rb_right; - else if (ret > 0) + else if (delayed_item->index > index) node = node->rb_left; else return delayed_item; @@ -379,9 +380,9 @@ static struct btrfs_delayed_item *__btrfs_lookup_delayed_item( static struct btrfs_delayed_item *__btrfs_lookup_delayed_insertion_item( struct btrfs_delayed_node *delayed_node, - struct btrfs_key *key) + u64 index) { - return __btrfs_lookup_delayed_item(&delayed_node->ins_root.rb_root, key, + return __btrfs_lookup_delayed_item(&delayed_node->ins_root.rb_root, index, NULL, NULL); } @@ -392,7 +393,6 @@ static int __btrfs_add_delayed_item(struct btrfs_delayed_node *delayed_node, struct rb_node *parent_node = NULL; struct rb_root_cached *root; struct btrfs_delayed_item *item; - int cmp; bool leftmost = true; if (ins->ins_or_del == BTRFS_DELAYED_INSERTION_ITEM) @@ -409,11 +409,10 @@ static int __btrfs_add_delayed_item(struct btrfs_delayed_node *delayed_node, item = rb_entry(parent_node, struct btrfs_delayed_item, rb_node); - cmp = btrfs_comp_cpu_keys(&item->key, &ins->key); - if (cmp < 0) { + if (item->index < ins->index) { p = &(*p)->rb_right; leftmost = false; - } else if (cmp > 0) { + } else if (item->index > ins->index) { p = &(*p)->rb_left; } else { return -EEXIST; @@ -422,14 +421,10 @@ static int __btrfs_add_delayed_item(struct btrfs_delayed_node *delayed_node, rb_link_node(node, parent_node, p); rb_insert_color_cached(node, root, leftmost); - ins->delayed_node = delayed_node; - - /* Delayed items are always for dir index items. */ - ASSERT(ins->key.type == BTRFS_DIR_INDEX_KEY); if (ins->ins_or_del == BTRFS_DELAYED_INSERTION_ITEM && - ins->key.offset >= delayed_node->index_cnt) - delayed_node->index_cnt = ins->key.offset + 1; + ins->index >= delayed_node->index_cnt) + delayed_node->index_cnt = ins->index + 1; delayed_node->count++; atomic_inc(&delayed_node->root->fs_info->delayed_root->items); @@ -451,9 +446,10 @@ static void __btrfs_remove_delayed_item(struct btrfs_delayed_item *delayed_item) struct rb_root_cached *root; struct btrfs_delayed_root *delayed_root; - /* Not associated with any delayed_node */ - if (!delayed_item->delayed_node) + /* Not inserted, ignore it. */ + if (RB_EMPTY_NODE(&delayed_item->rb_node)) return; + delayed_root = delayed_item->delayed_node->root->fs_info->delayed_root; BUG_ON(!delayed_root); @@ -466,6 +462,7 @@ static void __btrfs_remove_delayed_item(struct btrfs_delayed_item *delayed_item) root = &delayed_item->delayed_node->del_root; rb_erase_cached(&delayed_item->rb_node, root); + RB_CLEAR_NODE(&delayed_item->rb_node); delayed_item->delayed_node->count--; finish_one_item(delayed_root); @@ -544,7 +541,7 @@ static int btrfs_delayed_item_reserve_metadata(struct btrfs_trans_handle *trans, ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes, true); if (!ret) { trace_btrfs_space_reservation(fs_info, "delayed_item", - item->key.objectid, + item->delayed_node->inode_id, num_bytes, 1); /* * For insertions we track reserved metadata space by accounting @@ -573,8 +570,8 @@ static void btrfs_delayed_item_release_metadata(struct btrfs_root *root, * to release/reserve qgroup space. */ trace_btrfs_space_reservation(fs_info, "delayed_item", - item->key.objectid, item->bytes_reserved, - 0); + item->delayed_node->inode_id, + item->bytes_reserved, 0); btrfs_block_rsv_release(fs_info, rsv, item->bytes_reserved, NULL); } @@ -687,6 +684,7 @@ static int btrfs_insert_delayed_item(struct btrfs_trans_handle *trans, struct btrfs_delayed_item *next; const int max_size = BTRFS_LEAF_DATA_SIZE(fs_info); struct btrfs_item_batch batch; + struct btrfs_key first_key; int total_size; char *ins_data = NULL; int ret; @@ -731,8 +729,7 @@ static int btrfs_insert_delayed_item(struct btrfs_trans_handle *trans, * We cannot allow gaps in the key space if we're doing log * replay. */ - if (continuous_keys_only && - (next->key.offset != curr->key.offset + 1)) + if (continuous_keys_only && (next->index != curr->index + 1)) break; ASSERT(next->bytes_reserved == 0); @@ -749,7 +746,10 @@ static int btrfs_insert_delayed_item(struct btrfs_trans_handle *trans, } if (batch.nr == 1) { - batch.keys = &first_item->key; + first_key.objectid = node->inode_id; + first_key.type = BTRFS_DIR_INDEX_KEY; + first_key.offset = first_item->index; + batch.keys = &first_key; batch.data_sizes = &first_item->data_len; } else { struct btrfs_key *ins_keys; @@ -767,7 +767,9 @@ static int btrfs_insert_delayed_item(struct btrfs_trans_handle *trans, batch.keys = ins_keys; batch.data_sizes = ins_sizes; list_for_each_entry(curr, &item_list, tree_list) { - ins_keys[i] = curr->key; + ins_keys[i].objectid = node->inode_id; + ins_keys[i].type = BTRFS_DIR_INDEX_KEY; + ins_keys[i].offset = curr->index; ins_sizes[i] = curr->data_len; i++; } @@ -863,6 +865,7 @@ static int btrfs_batch_delete_items(struct btrfs_trans_handle *trans, struct btrfs_path *path, struct btrfs_delayed_item *item) { + const u64 ino = item->delayed_node->inode_id; struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_delayed_item *curr, *next; struct extent_buffer *leaf = path->nodes[0]; @@ -901,7 +904,9 @@ static int btrfs_batch_delete_items(struct btrfs_trans_handle *trans, slot++; btrfs_item_key_to_cpu(leaf, &key, slot); - if (btrfs_comp_cpu_keys(&next->key, &key) != 0) + if (key.objectid != ino || + key.type != BTRFS_DIR_INDEX_KEY || + key.offset != next->index) break; nitems++; curr = next; @@ -919,9 +924,8 @@ static int btrfs_batch_delete_items(struct btrfs_trans_handle *trans, * Check btrfs_delayed_item_reserve_metadata() to see why we * don't need to release/reserve qgroup space. */ - trace_btrfs_space_reservation(fs_info, "delayed_item", - item->key.objectid, total_reserved_size, - 0); + trace_btrfs_space_reservation(fs_info, "delayed_item", ino, + total_reserved_size, 0); btrfs_block_rsv_release(fs_info, &fs_info->delayed_block_rsv, total_reserved_size, NULL); } @@ -939,8 +943,12 @@ static int btrfs_delete_delayed_items(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_delayed_node *node) { + struct btrfs_key key; int ret = 0; + key.objectid = node->inode_id; + key.type = BTRFS_DIR_INDEX_KEY; + while (ret == 0) { struct btrfs_delayed_item *item; @@ -951,7 +959,8 @@ static int btrfs_delete_delayed_items(struct btrfs_trans_handle *trans, break; } - ret = btrfs_search_slot(trans, root, &item->key, path, -1, 1); + key.offset = item->index; + ret = btrfs_search_slot(trans, root, &key, path, -1, 1); if (ret > 0) { /* * There's no matching item in the leaf. This means we @@ -1456,15 +1465,14 @@ int btrfs_insert_delayed_dir_index(struct btrfs_trans_handle *trans, if (IS_ERR(delayed_node)) return PTR_ERR(delayed_node); - delayed_item = btrfs_alloc_delayed_item(sizeof(*dir_item) + name_len); + delayed_item = btrfs_alloc_delayed_item(sizeof(*dir_item) + name_len, + delayed_node); if (!delayed_item) { ret = -ENOMEM; goto release_node; } - delayed_item->key.objectid = btrfs_ino(dir); - delayed_item->key.type = BTRFS_DIR_INDEX_KEY; - delayed_item->key.offset = index; + delayed_item->index = index; delayed_item->ins_or_del = BTRFS_DELAYED_INSERTION_ITEM; dir_item = (struct btrfs_dir_item *)delayed_item->data; @@ -1536,12 +1544,12 @@ release_node: static int btrfs_delete_delayed_insertion_item(struct btrfs_fs_info *fs_info, struct btrfs_delayed_node *node, - struct btrfs_key *key) + u64 index) { struct btrfs_delayed_item *item; mutex_lock(&node->mutex); - item = __btrfs_lookup_delayed_insertion_item(node, key); + item = __btrfs_lookup_delayed_insertion_item(node, index); if (!item) { mutex_unlock(&node->mutex); return 1; @@ -1587,29 +1595,23 @@ int btrfs_delete_delayed_dir_index(struct btrfs_trans_handle *trans, { struct btrfs_delayed_node *node; struct btrfs_delayed_item *item; - struct btrfs_key item_key; int ret; node = btrfs_get_or_create_delayed_node(dir); if (IS_ERR(node)) return PTR_ERR(node); - item_key.objectid = btrfs_ino(dir); - item_key.type = BTRFS_DIR_INDEX_KEY; - item_key.offset = index; - - ret = btrfs_delete_delayed_insertion_item(trans->fs_info, node, - &item_key); + ret = btrfs_delete_delayed_insertion_item(trans->fs_info, node, index); if (!ret) goto end; - item = btrfs_alloc_delayed_item(0); + item = btrfs_alloc_delayed_item(0, node); if (!item) { ret = -ENOMEM; goto end; } - item->key = item_key; + item->index = index; item->ins_or_del = BTRFS_DELAYED_DELETION_ITEM; ret = btrfs_delayed_item_reserve_metadata(trans, item); @@ -1741,9 +1743,9 @@ int btrfs_should_delete_dir_index(struct list_head *del_list, int ret = 0; list_for_each_entry(curr, del_list, readdir_list) { - if (curr->key.offset > index) + if (curr->index > index) break; - if (curr->key.offset == index) { + if (curr->index == index) { ret = 1; break; } @@ -1777,13 +1779,13 @@ int btrfs_readdir_delayed_dir_index(struct dir_context *ctx, list_for_each_entry_safe(curr, next, ins_list, readdir_list) { list_del(&curr->readdir_list); - if (curr->key.offset < ctx->pos) { + if (curr->index < ctx->pos) { if (refcount_dec_and_test(&curr->refs)) kfree(curr); continue; } - ctx->pos = curr->key.offset; + ctx->pos = curr->index; di = (struct btrfs_dir_item *)curr->data; name = (char *)(di + 1); diff --git a/fs/btrfs/delayed-inode.h b/fs/btrfs/delayed-inode.h index 9795dc295a18..fd6fe785f748 100644 --- a/fs/btrfs/delayed-inode.h +++ b/fs/btrfs/delayed-inode.h @@ -73,7 +73,8 @@ struct btrfs_delayed_node { struct btrfs_delayed_item { struct rb_node rb_node; - struct btrfs_key key; + /* Offset value of the corresponding dir index key. */ + u64 index; struct list_head tree_list; /* used for batch insert/delete items */ struct list_head readdir_list; /* used for readdir items */ u64 bytes_reserved; -- 2.20.1