From d588adae3b97241ee2e837a4dd74674b9a209cd6 Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Wed, 11 Jan 2023 11:36:17 +0000 Subject: [PATCH] btrfs: add an api to delete a specific entry from the lru cache In order to replace the open coded name cache in send with the lru cache, we need an API for the lru cache to delete a specific entry for which we did a previous lookup. This adds the API for it, and a next patch in the series will use it. This patch is part of a larger patchset and the changelog of the last patch in the series contains a sample performance test and results. The patches that comprise the patchset are the following: btrfs: send: directly return from did_overwrite_ref() and simplify it btrfs: send: avoid unnecessary generation search at did_overwrite_ref() btrfs: send: directly return from will_overwrite_ref() and simplify it btrfs: send: avoid extra b+tree searches when checking reference overrides btrfs: send: remove send_progress argument from can_rmdir() btrfs: send: avoid duplicated orphan dir allocation and initialization btrfs: send: avoid unnecessary orphan dir rbtree search at can_rmdir() btrfs: send: reduce searches on parent root when checking if dir can be removed btrfs: send: iterate waiting dir move rbtree only once when processing refs btrfs: send: initialize all the red black trees earlier btrfs: send: genericize the backref cache to allow it to be reused btrfs: adapt lru cache to allow for 64 bits keys on 32 bits systems btrfs: send: cache information about created directories btrfs: allow a generation number to be associated with lru cache entries btrfs: add an api to delete a specific entry from the lru cache btrfs: send: use the lru cache to implement the name cache btrfs: send: update size of roots array for backref cache entries btrfs: send: cache utimes operations for directories if possible Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/lru_cache.c | 16 ++++++++++++---- fs/btrfs/lru_cache.h | 2 ++ 2 files changed, 14 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/lru_cache.c b/fs/btrfs/lru_cache.c index 01821d66a8a2..38722dc07676 100644 --- a/fs/btrfs/lru_cache.c +++ b/fs/btrfs/lru_cache.c @@ -57,8 +57,16 @@ struct btrfs_lru_cache_entry *btrfs_lru_cache_lookup(struct btrfs_lru_cache *cac return entry; } -static void delete_entry(struct btrfs_lru_cache *cache, - struct btrfs_lru_cache_entry *entry) +/* + * Remove an entry from the cache. + * + * @cache: The cache to remove from. + * @entry: The entry to remove from the cache. + * + * Note: this also frees the memory used by the entry. + */ +void btrfs_lru_cache_remove(struct btrfs_lru_cache *cache, + struct btrfs_lru_cache_entry *entry) { struct list_head *prev = entry->list.prev; @@ -127,7 +135,7 @@ int btrfs_lru_cache_store(struct btrfs_lru_cache *cache, lru_entry = list_first_entry(&cache->lru_list, struct btrfs_lru_cache_entry, lru_list); - delete_entry(cache, lru_entry); + btrfs_lru_cache_remove(cache, lru_entry); } list_add_tail(&new_entry->lru_list, &cache->lru_list); @@ -149,7 +157,7 @@ void btrfs_lru_cache_clear(struct btrfs_lru_cache *cache) struct btrfs_lru_cache_entry *tmp; list_for_each_entry_safe(entry, tmp, &cache->lru_list, lru_list) - delete_entry(cache, entry); + btrfs_lru_cache_remove(cache, entry); ASSERT(cache->size == 0); ASSERT(mtree_empty(&cache->entries)); diff --git a/fs/btrfs/lru_cache.h b/fs/btrfs/lru_cache.h index c1f20f4b7038..a97206f04990 100644 --- a/fs/btrfs/lru_cache.h +++ b/fs/btrfs/lru_cache.h @@ -58,6 +58,8 @@ struct btrfs_lru_cache_entry *btrfs_lru_cache_lookup(struct btrfs_lru_cache *cac int btrfs_lru_cache_store(struct btrfs_lru_cache *cache, struct btrfs_lru_cache_entry *new_entry, gfp_t gfp); +void btrfs_lru_cache_remove(struct btrfs_lru_cache *cache, + struct btrfs_lru_cache_entry *entry); void btrfs_lru_cache_clear(struct btrfs_lru_cache *cache); #endif