The iproute2 program ss reads /proc/slabinfo to get TCP socket
statistics; therefore those kmem cache's can not be merged.
This patch adds a new flag to block merging in these kind
of cases.
Signed-off-by: Stephen Hemminger <step...@networkplumber.org>
---
include/linux/slab.h | 6 ++++++
mm/slab_common.c | 2 +-
2 files changed, 7 insertions(+), 1 deletion(-)
diff --git a/include/linux/slab.h b/include/linux/slab.h
index 231abc8976c5..867acc2ddcbc 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -108,6 +108,12 @@
#define SLAB_KASAN 0
#endif
+/*
+ * Some old applications may want to read/write particular slab cache
+ * by name and therefore this can not be merged.
+ */
+#define SLAB_VISIBLE_UAPI 0x10000000UL
+
/* The following flags affect the page allocator grouping pages by mobility */
/* Objects are reclaimable */
#define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0x00020000U)
diff --git a/mm/slab_common.c b/mm/slab_common.c
index 10f127b2de7c..71eb5fc63cf8 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -49,7 +49,7 @@ static DECLARE_WORK(slab_caches_to_rcu_destroy_work,
*/
#define SLAB_NEVER_MERGE (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
SLAB_TRACE | SLAB_TYPESAFE_BY_RCU | SLAB_NOLEAKTRACE | \
- SLAB_FAILSLAB | SLAB_KASAN)
+ SLAB_FAILSLAB | SLAB_KASAN | SLAB_VISIBLE_UAPI)
#define SLAB_MERGE_SAME (SLAB_RECLAIM_ACCOUNT | SLAB_CACHE_DMA | \
SLAB_ACCOUNT)
--
2.16.1
