mbcache: get rid of _e_hash_list_head (dc8d5e56) · Commits · 戴 / test

fs/mbcache.c

+10 −31

Original line number	Diff line number	Diff line
		@@ -45,27 +45,10 @@ static struct kmem_cache *mb_entry_cache;
		static unsigned long mb_cache_shrink(struct mb_cache *cache,
		unsigned int nr_to_scan);

		static inline bool mb_cache_entry_referenced(struct mb_cache_entry *entry)
		{
		return entry->_e_hash_list_head & 1;
		}

		static inline void mb_cache_entry_set_referenced(struct mb_cache_entry *entry)
		{
		entry->_e_hash_list_head \|= 1;
		}

		static inline void mb_cache_entry_clear_referenced(
		struct mb_cache_entry *entry)
		{
		entry->_e_hash_list_head &= ~1;
		}

		static inline struct hlist_bl_head *mb_cache_entry_head(
		struct mb_cache_entry *entry)
		static inline struct hlist_bl_head mb_cache_entry_head(struct mb_cache cache,
		u32 key)
		{
		return (struct hlist_bl_head *)
		(entry->_e_hash_list_head & ~1);
		return &cache->c_hash[hash_32(key, cache->c_bucket_bits)];
		}

		/*
		@@ -108,8 +91,7 @@ int mb_cache_entry_create(struct mb_cache *cache, gfp_t mask, u32 key,
		atomic_set(&entry->e_refcnt, 1);
		entry->e_key = key;
		entry->e_block = block;
		head = &cache->c_hash[hash_32(key, cache->c_bucket_bits)];
		entry->_e_hash_list_head = (unsigned long)head;
		head = mb_cache_entry_head(cache, key);
		hlist_bl_lock(head);
		hlist_bl_for_each_entry(dup, dup_node, head, e_hash_list) {
		if (dup->e_key == key && dup->e_block == block) {
		@@ -146,10 +128,7 @@ static struct mb_cache_entry __entry_find(struct mb_cache cache,
		struct hlist_bl_node *node;
		struct hlist_bl_head *head;

		if (entry)
		head = mb_cache_entry_head(entry);
		else
		head = &cache->c_hash[hash_32(key, cache->c_bucket_bits)];
		head = mb_cache_entry_head(cache, key);
		hlist_bl_lock(head);
		if (entry && !hlist_bl_unhashed(&entry->e_hash_list))
		node = entry->e_hash_list.next;
		@@ -219,7 +198,7 @@ void mb_cache_entry_delete_block(struct mb_cache *cache, u32 key,
		struct hlist_bl_head *head;
		struct mb_cache_entry *entry;

		head = &cache->c_hash[hash_32(key, cache->c_bucket_bits)];
		head = mb_cache_entry_head(cache, key);
		hlist_bl_lock(head);
		hlist_bl_for_each_entry(entry, node, head, e_hash_list) {
		if (entry->e_key == key && entry->e_block == block) {
		@@ -250,7 +229,7 @@ EXPORT_SYMBOL(mb_cache_entry_delete_block);
		void mb_cache_entry_touch(struct mb_cache *cache,
		struct mb_cache_entry *entry)
		{
		mb_cache_entry_set_referenced(entry);
		entry->e_referenced = 1;
		}
		EXPORT_SYMBOL(mb_cache_entry_touch);

		@@ -275,8 +254,8 @@ static unsigned long mb_cache_shrink(struct mb_cache *cache,
		while (nr_to_scan-- && !list_empty(&cache->c_list)) {
		entry = list_first_entry(&cache->c_list,
		struct mb_cache_entry, e_list);
		if (mb_cache_entry_referenced(entry)) {
		mb_cache_entry_clear_referenced(entry);
		if (entry->e_referenced) {
		entry->e_referenced = 0;
		list_move_tail(&cache->c_list, &entry->e_list);
		continue;
		}
		@@ -287,7 +266,7 @@ static unsigned long mb_cache_shrink(struct mb_cache *cache,
		* from under us.
		*/
		spin_unlock(&cache->c_list_lock);
		head = mb_cache_entry_head(entry);
		head = mb_cache_entry_head(cache, entry->e_key);
		hlist_bl_lock(head);
		if (!hlist_bl_unhashed(&entry->e_hash_list)) {
		hlist_bl_del_init(&entry->e_hash_list);

include/linux/mbcache.h

+2 −6

Original line number	Diff line number	Diff line
		@@ -12,18 +12,14 @@ 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 bitlock in e_hash_list_head */
		/* Hash table list - protected by hash chain bitlock */
		struct hlist_bl_node e_hash_list;
		atomic_t e_refcnt;
		/* Key in hash - stable during lifetime of the entry */
		u32 e_key;
		u32 e_referenced:1;
		/* Block number of hashed block - stable during lifetime of the entry */
		sector_t e_block;
		/*
		* Head of hash list (for list bit lock) - stable. Combined with
		* referenced bit of entry
		*/
		unsigned long _e_hash_list_head;
		};

		struct mb_cache *mb_cache_create(int bucket_bits);

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