Commit c1a0ecb8 authored by Johannes Weiner's avatar Johannes Weiner Committed by Andrew Morton
Browse files

mm: zswap: function ordering: zswap_pools 

Move the operations against the global zswap_pools list (current pool,
last, find) to the pool section.

Link: https://lkml.kernel.org/r/20240130014208.565554-13-hannes@cmpxchg.org


Signed-off-by: default avatarJohannes Weiner <hannes@cmpxchg.org>
Reviewed-by: default avatarNhat Pham <nphamcs@gmail.com>
Cc: Chengming Zhou <zhouchengming@bytedance.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 39f3ec8e

mm/zswap.c

+73 −77
Original line number Diff line number Diff line
@@ -517,6 +517,79 @@ static void zswap_pool_put(struct zswap_pool *pool) 
	kref_put(&pool->kref, __zswap_pool_empty);

}



static struct zswap_pool *__zswap_pool_current(void)

{

	struct zswap_pool *pool;



	pool = list_first_or_null_rcu(&zswap_pools, typeof(*pool), list);

	WARN_ONCE(!pool && zswap_has_pool,

		  "%s: no page storage pool!\n", __func__);



	return pool;

}



static struct zswap_pool *zswap_pool_current(void)

{

	assert_spin_locked(&zswap_pools_lock);



	return __zswap_pool_current();

}



static struct zswap_pool *zswap_pool_current_get(void)

{

	struct zswap_pool *pool;



	rcu_read_lock();



	pool = __zswap_pool_current();

	if (!zswap_pool_get(pool))

		pool = NULL;



	rcu_read_unlock();



	return pool;

}



static struct zswap_pool *zswap_pool_last_get(void)

{

	struct zswap_pool *pool, *last = NULL;



	rcu_read_lock();



	list_for_each_entry_rcu(pool, &zswap_pools, list)

		last = pool;

	WARN_ONCE(!last && zswap_has_pool,

		  "%s: no page storage pool!\n", __func__);

	if (!zswap_pool_get(last))

		last = NULL;



	rcu_read_unlock();



	return last;

}



/* type and compressor must be null-terminated */

static struct zswap_pool *zswap_pool_find_get(char *type, char *compressor)

{

	struct zswap_pool *pool;



	assert_spin_locked(&zswap_pools_lock);



	list_for_each_entry_rcu(pool, &zswap_pools, list) {

		if (strcmp(pool->tfm_name, compressor))

			continue;

		/* all zpools share the same type */

		if (strcmp(zpool_get_type(pool->zpools[0]), type))

			continue;

		/* if we can't get it, it's about to be destroyed */

		if (!zswap_pool_get(pool))

			continue;

		return pool;

	}



	return NULL;

}



/* should be called under RCU */

#ifdef CONFIG_MEMCG

static inline struct mem_cgroup *mem_cgroup_from_entry(struct zswap_entry *entry)
@@ -937,83 +1010,6 @@ static int zswap_cpu_comp_dead(unsigned int cpu, struct hlist_node *node) 
	return 0;

}



/*********************************

* pool functions

**********************************/



static struct zswap_pool *__zswap_pool_current(void)

{

	struct zswap_pool *pool;



	pool = list_first_or_null_rcu(&zswap_pools, typeof(*pool), list);

	WARN_ONCE(!pool && zswap_has_pool,

		  "%s: no page storage pool!\n", __func__);



	return pool;

}



static struct zswap_pool *zswap_pool_current(void)

{

	assert_spin_locked(&zswap_pools_lock);



	return __zswap_pool_current();

}



static struct zswap_pool *zswap_pool_current_get(void)

{

	struct zswap_pool *pool;



	rcu_read_lock();



	pool = __zswap_pool_current();

	if (!zswap_pool_get(pool))

		pool = NULL;



	rcu_read_unlock();



	return pool;

}



static struct zswap_pool *zswap_pool_last_get(void)

{

	struct zswap_pool *pool, *last = NULL;



	rcu_read_lock();



	list_for_each_entry_rcu(pool, &zswap_pools, list)

		last = pool;

	WARN_ONCE(!last && zswap_has_pool,

		  "%s: no page storage pool!\n", __func__);

	if (!zswap_pool_get(last))

		last = NULL;



	rcu_read_unlock();



	return last;

}



/* type and compressor must be null-terminated */

static struct zswap_pool *zswap_pool_find_get(char *type, char *compressor)

{

	struct zswap_pool *pool;



	assert_spin_locked(&zswap_pools_lock);



	list_for_each_entry_rcu(pool, &zswap_pools, list) {

		if (strcmp(pool->tfm_name, compressor))

			continue;

		/* all zpools share the same type */

		if (strcmp(zpool_get_type(pool->zpools[0]), type))

			continue;

		/* if we can't get it, it's about to be destroyed */

		if (!zswap_pool_get(pool))

			continue;

		return pool;

	}



	return NULL;

}



static enum lru_status shrink_memcg_cb(struct list_head *item, struct list_lru_one *l,

				       spinlock_t *lock, void *arg)

{