The patch titled
Subject: mm: zswap: function ordering: pool refcounting
has been added to the -mm mm-unstable branch. Its filename is
mm-zswap-function-ordering-pool-refcounting.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-zswap-function-ordering-pool-refcounting.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Johannes Weiner <hannes@xxxxxxxxxxx>
Subject: mm: zswap: function ordering: pool refcounting
Date: Mon, 29 Jan 2024 20:36:47 -0500
Move pool refcounting functions into the pool section. First the
destroy functions, then the get and put which uses them.
__zswap_pool_empty() has an upward reference to the global
zswap_pools, to sanity check it's not the currently active pool that's
being freed. That gets the forward decl for zswap_pool_cuyrrent().
This puts the get and put function above all callers, so kill the
forward decls as well.
Link: https://lkml.kernel.org/r/20240130014208.565554-12-hannes@xxxxxxxxxxx
Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx>
Cc: Nhat Pham <nphamcs@xxxxxxxxx>
Cc: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/zswap.c | 94 +++++++++++++++++++++++++--------------------------
1 file changed, 47 insertions(+), 47 deletions(-)
--- a/mm/zswap.c~mm-zswap-function-ordering-pool-refcounting
+++ a/mm/zswap.c
@@ -278,8 +278,6 @@ static inline struct zswap_tree *swap_zs
static int zswap_writeback_entry(struct zswap_entry *entry,
swp_entry_t swpentry);
-static int zswap_pool_get(struct zswap_pool *pool);
-static void zswap_pool_put(struct zswap_pool *pool);
static bool zswap_is_full(void)
{
@@ -472,6 +470,53 @@ static void zswap_pool_destroy(struct zs
kfree(pool);
}
+static void __zswap_pool_release(struct work_struct *work)
+{
+ struct zswap_pool *pool = container_of(work, typeof(*pool),
+ release_work);
+
+ synchronize_rcu();
+
+ /* nobody should have been able to get a kref... */
+ WARN_ON(kref_get_unless_zero(&pool->kref));
+
+ /* pool is now off zswap_pools list and has no references. */
+ zswap_pool_destroy(pool);
+}
+
+static struct zswap_pool *zswap_pool_current(void);
+
+static void __zswap_pool_empty(struct kref *kref)
+{
+ struct zswap_pool *pool;
+
+ pool = container_of(kref, typeof(*pool), kref);
+
+ spin_lock(&zswap_pools_lock);
+
+ WARN_ON(pool == zswap_pool_current());
+
+ list_del_rcu(&pool->list);
+
+ INIT_WORK(&pool->release_work, __zswap_pool_release);
+ schedule_work(&pool->release_work);
+
+ spin_unlock(&zswap_pools_lock);
+}
+
+static int __must_check zswap_pool_get(struct zswap_pool *pool)
+{
+ if (!pool)
+ return 0;
+
+ return kref_get_unless_zero(&pool->kref);
+}
+
+static void zswap_pool_put(struct zswap_pool *pool)
+{
+ kref_put(&pool->kref, __zswap_pool_empty);
+}
+
/* should be called under RCU */
#ifdef CONFIG_MEMCG
static inline struct mem_cgroup *mem_cgroup_from_entry(struct zswap_entry *entry)
@@ -1122,51 +1167,6 @@ resched:
zswap_pool_put(pool);
}
-static int __must_check zswap_pool_get(struct zswap_pool *pool)
-{
- if (!pool)
- return 0;
-
- return kref_get_unless_zero(&pool->kref);
-}
-
-static void __zswap_pool_release(struct work_struct *work)
-{
- struct zswap_pool *pool = container_of(work, typeof(*pool),
- release_work);
-
- synchronize_rcu();
-
- /* nobody should have been able to get a kref... */
- WARN_ON(kref_get_unless_zero(&pool->kref));
-
- /* pool is now off zswap_pools list and has no references. */
- zswap_pool_destroy(pool);
-}
-
-static void __zswap_pool_empty(struct kref *kref)
-{
- struct zswap_pool *pool;
-
- pool = container_of(kref, typeof(*pool), kref);
-
- spin_lock(&zswap_pools_lock);
-
- WARN_ON(pool == zswap_pool_current());
-
- list_del_rcu(&pool->list);
-
- INIT_WORK(&pool->release_work, __zswap_pool_release);
- schedule_work(&pool->release_work);
-
- spin_unlock(&zswap_pools_lock);
-}
-
-static void zswap_pool_put(struct zswap_pool *pool)
-{
- kref_put(&pool->kref, __zswap_pool_empty);
-}
-
/*********************************
* param callbacks
**********************************/
_
Patches currently in -mm which might be from hannes@xxxxxxxxxxx are
mm-zswap-fix-objcg-use-after-free-in-entry-destruction.patch
mm-zswap-rename-zswap_free_entry-to-zswap_entry_free.patch
mm-zswap-inline-and-remove-zswap_entry_find_get.patch
mm-zswap-move-zswap_invalidate_entry-to-related-functions.patch
mm-zswap-warn-when-referencing-a-dead-entry.patch
mm-zswap-clean-up-zswap_entry_put.patch
mm-zswap-rename-__zswap_load-to-zswap_decompress.patch
mm-zswap-break-out-zwap_compress.patch
mm-zswap-further-cleanup-zswap_store.patch
mm-zswap-simplify-zswap_invalidate.patch
mm-zswap-function-ordering-pool-alloc-free.patch
mm-zswap-function-ordering-pool-refcounting.patch
mm-zswap-function-ordering-zswap_pools.patch
mm-zswap-function-ordering-pool-params.patch
mm-zswap-function-ordering-public-lru-api.patch
mm-zswap-function-ordering-move-entry-sections-out-of-lru-section.patch
mm-zswap-function-ordering-move-entry-section-out-of-tree-section.patch
mm-zswap-function-ordering-compress-decompress-functions.patch
mm-zswap-function-ordering-per-cpu-compression-infra.patch
mm-zswap-function-ordering-writeback.patch
mm-zswap-function-ordering-shrink_memcg_cb.patch
