[PATCH] knfsd: Create cache_lookup function instead of using a macro to declare one (15a5f6bd) · Commits · 戴 / test

include/linux/sunrpc/cache.h

+12 −0

Original line number	Diff line number	Diff line
		@@ -81,6 +81,11 @@ struct cache_detail {
		struct cache_detail *cd,
		struct cache_head *h);

		struct cache_head * (*alloc)(void);
		int (match)(struct cache_head orig, struct cache_head *new);
		void (init)(struct cache_head orig, struct cache_head *new);
		void (update)(struct cache_head orig, struct cache_head *new);

		/* fields below this comment are for internal use
		* and should not be touched by cache owners
		*/
		@@ -237,6 +242,13 @@ RTN *FNAME ARGS \
		& FUNC##_cache, FUNC##_hash(item), FUNC##_match(item, tmp), \
		STRUCT##_init(new, item), STRUCT##_update(tmp, item))

		extern struct cache_head *
		sunrpc_cache_lookup(struct cache_detail *detail,
		struct cache_head *key, int hash);
		extern struct cache_head *
		sunrpc_cache_update(struct cache_detail *detail,
		struct cache_head new, struct cache_head old, int hash);


		#define cache_for_each(pos, detail, index, member) \
		for (({read_lock(&(detail)->hash_lock); index = (detail)->hash_size;}) ; \

net/sunrpc/cache.c

+98 −0

Original line number	Diff line number	Diff line
		@@ -47,6 +47,104 @@ void cache_init(struct cache_head *h)
		h->last_refresh = now;
		}

		struct cache_head sunrpc_cache_lookup(struct cache_detail detail,
		struct cache_head *key, int hash)
		{
		struct cache_head head, hp;
		struct cache_head *new = NULL;

		head = &detail->hash_table[hash];

		read_lock(&detail->hash_lock);

		for (hp=head; hp != NULL ; hp = &(hp)->next) {
		struct cache_head tmp = hp;
		if (detail->match(tmp, key)) {
		cache_get(tmp);
		read_unlock(&detail->hash_lock);
		return tmp;
		}
		}
		read_unlock(&detail->hash_lock);
		/* Didn't find anything, insert an empty entry */

		new = detail->alloc();
		if (!new)
		return NULL;
		cache_init(new);

		write_lock(&detail->hash_lock);

		/* check if entry appeared while we slept */
		for (hp=head; hp != NULL ; hp = &(hp)->next) {
		struct cache_head tmp = hp;
		if (detail->match(tmp, key)) {
		cache_get(tmp);
		write_unlock(&detail->hash_lock);
		detail->cache_put(new, detail);
		return tmp;
		}
		}
		detail->init(new, key);
		new->next = *head;
		*head = new;
		detail->entries++;
		cache_get(new);
		write_unlock(&detail->hash_lock);

		return new;
		}
		EXPORT_SYMBOL(sunrpc_cache_lookup);

		struct cache_head sunrpc_cache_update(struct cache_detail detail,
		struct cache_head new, struct cache_head old, int hash)
		{
		/* The 'old' entry is to be replaced by 'new'.
		* If 'old' is not VALID, we update it directly,
		* otherwise we need to replace it
		*/
		struct cache_head **head;
		struct cache_head *tmp;

		if (!test_bit(CACHE_VALID, &old->flags)) {
		write_lock(&detail->hash_lock);
		if (!test_bit(CACHE_VALID, &old->flags)) {
		if (test_bit(CACHE_NEGATIVE, &new->flags))
		set_bit(CACHE_NEGATIVE, &old->flags);
		else
		detail->update(old, new);
		/* FIXME cache_fresh should come first */
		write_unlock(&detail->hash_lock);
		cache_fresh(detail, old, new->expiry_time);
		return old;
		}
		write_unlock(&detail->hash_lock);
		}
		/* We need to insert a new entry */
		tmp = detail->alloc();
		if (!tmp) {
		detail->cache_put(old, detail);
		return NULL;
		}
		cache_init(tmp);
		detail->init(tmp, old);
		head = &detail->hash_table[hash];

		write_lock(&detail->hash_lock);
		if (test_bit(CACHE_NEGATIVE, &new->flags))
		set_bit(CACHE_NEGATIVE, &tmp->flags);
		else
		detail->update(tmp, new);
		tmp->next = *head;
		*head = tmp;
		cache_get(tmp);
		write_unlock(&detail->hash_lock);
		cache_fresh(detail, tmp, new->expiry_time);
		cache_fresh(detail, old, 0);
		detail->cache_put(old, detail);
		return tmp;
		}
		EXPORT_SYMBOL(sunrpc_cache_update);

		static int cache_make_upcall(struct cache_detail detail, struct cache_head h);
		/*

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