[PATCH v4 21/36] lib: add codetag reference into slabobj_ext

[Suren Baghdasaryan <surenb@google.com>]

To store code tag for every slab object, a codetag reference is embedded
into slabobj_ext when CONFIG_MEM_ALLOC_PROFILING=y.

Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Co-developed-by: Kent Overstreet <kent.overstreet@linux.dev>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
---
 include/linux/memcontrol.h | 5 +++++
 lib/Kconfig.debug          | 1 +
 2 files changed, 6 insertions(+)

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index f3584e98b640..2b010316016c 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -1653,7 +1653,12 @@ unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
  * if MEMCG_DATA_OBJEXTS is set.
  */
 struct slabobj_ext {
+#ifdef CONFIG_MEMCG_KMEM
 	struct obj_cgroup *objcg;
+#endif
+#ifdef CONFIG_MEM_ALLOC_PROFILING
+	union codetag_ref ref;
+#endif
 } __aligned(8);
 
 static inline void __inc_lruvec_kmem_state(void *p, enum node_stat_item idx)
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 7bbdb0ddb011..9ecfcdb54417 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -979,6 +979,7 @@ config MEM_ALLOC_PROFILING
 	depends on !DEBUG_FORCE_WEAK_PER_CPU
 	select CODE_TAGGING
 	select PAGE_EXTENSION
+	select SLAB_OBJ_EXT
 	help
 	  Track allocation source code and record total allocation size
 	  initiated at that code location. The mechanism can be used to track
-- 
2.44.0.rc0.258.g7320e95886-goog