Merge tag 'v6.0-rc6' into locking/core, to refresh the branch

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 24 insertions, 9 deletions

diff --git a/include/linux/mbcache.h b/include/linux/mbcache.h
index 20f1e3ff6013..2da63fd7b98f 100644
--- a/include/linux/mbcache.h
+++ b/include/linux/mbcache.h
@@ -13,8 +13,16 @@ struct mb_cache;
 struct mb_cache_entry {
 	/* List of entries in cache - protected by cache->c_list_lock */
 	struct list_head	e_list;
-	/* Hash table list - protected by hash chain bitlock */
+	/*
+	 * Hash table list - protected by hash chain bitlock. The entry is
+	 * guaranteed to be hashed while e_refcnt > 0.
+	 */
 	struct hlist_bl_node	e_hash_list;
+	/*
+	 * Entry refcount. Once it reaches zero, entry is unhashed and freed.
+	 * While refcount > 0, the entry is guaranteed to stay in the hash and
+	 * e.g. mb_cache_entry_try_delete() will fail.
+	 */
 	atomic_t		e_refcnt;
 	/* Key in hash - stable during lifetime of the entry */
 	u32			e_key;
@@ -29,17 +37,24 @@ void mb_cache_destroy(struct mb_cache *cache);
 
 int mb_cache_entry_create(struct mb_cache *cache, gfp_t mask, u32 key,
 			  u64 value, bool reusable);
-void __mb_cache_entry_free(struct mb_cache_entry *entry);
-static inline int mb_cache_entry_put(struct mb_cache *cache,
-				     struct mb_cache_entry *entry)
+void __mb_cache_entry_free(struct mb_cache *cache,
+			   struct mb_cache_entry *entry);
+void mb_cache_entry_wait_unused(struct mb_cache_entry *entry);
+static inline void mb_cache_entry_put(struct mb_cache *cache,
+				      struct mb_cache_entry *entry)
 {
-	if (!atomic_dec_and_test(&entry->e_refcnt))
-		return 0;
-	__mb_cache_entry_free(entry);
-	return 1;
+	unsigned int cnt = atomic_dec_return(&entry->e_refcnt);
+
+	if (cnt > 0) {
+		if (cnt <= 2)
+			wake_up_var(&entry->e_refcnt);
+		return;
+	}
+	__mb_cache_entry_free(cache, entry);
 }
 
-void mb_cache_entry_delete(struct mb_cache *cache, u32 key, u64 value);
+struct mb_cache_entry *mb_cache_entry_delete_or_get(struct mb_cache *cache,
+						    u32 key, u64 value);
 struct mb_cache_entry *mb_cache_entry_get(struct mb_cache *cache, u32 key,
 					  u64 value);
 struct mb_cache_entry *mb_cache_entry_find_first(struct mb_cache *cache,