[PATCH v1 7/8] mm: zswap: Optimally place members of struct zswap_pool, struct zswap_entry.

["Kanchana P. Sridhar" <kanchanapsridhar2026@gmail.com>]

Place and align the members of struct zswap_pool and struct zswap_entry
such that members used together in compress/decompress hot paths are
able to share the same cacheline. Minimize holes within these structs
while doing so.

Signed-off-by: Kanchana P. Sridhar <kanchanapsridhar2026@gmail.com>
---
 mm/zswap.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/mm/zswap.c b/mm/zswap.c
index 8ae67fd10522..ade84ac4076e 100644
--- a/mm/zswap.c
+++ b/mm/zswap.c
@@ -160,11 +160,11 @@ struct crypto_acomp_ctx {
 struct zswap_pool {
 	struct zs_pool *zs_pool;
 	struct crypto_acomp_ctx __percpu *acomp_ctx;
-	u8 compr_batch_size;
 	struct percpu_ref ref;
-	struct rcu_work release_rwork;
-	struct hlist_node node;
 	u8 idx;
+	u8 compr_batch_size;
+	struct hlist_node node;
+	struct rcu_work release_rwork;
 	char tfm_name[CRYPTO_MAX_ALG_NAME];
 };
 
@@ -202,10 +202,10 @@ static struct shrinker *zswap_shrinker;
  *              logic if referenced is unset. See comments in the shrinker
  *              section for context.
  * nid - NUMA node id of the page for which this is the zswap entry.
- * pool_idx - id of the zswap_pool that the entry's data is in.
  * handle - zsmalloc allocation handle that stores the compressed page data
  * objcg - the obj_cgroup that the compressed memory is charged to
  * lru - handle to the pool's lru used to evict pages.
+ * pool_idx - id of the zswap_pool that the entry's data is in.
  */
 struct zswap_entry {
 	swp_entry_t swpentry;
@@ -214,10 +214,10 @@ struct zswap_entry {
 		bool referenced:1;
 	};
 	int nid;
-	u8 pool_idx;
 	unsigned long handle;
 	struct obj_cgroup *objcg;
 	struct list_head lru;
+	u8 pool_idx;
 };
 
 /*
-- 
2.39.5