[PATCH 1/1] mm, slab: move allocation tagging code in the alloc path into a hook

From: Suren Baghdasaryan
Date: Tue Jul 02 2024 - 21:54:06 EST


Move allocation tagging specific code in the allocation path into
alloc_tagging_slab_alloc_hook, similar to how freeing path uses
alloc_tagging_slab_free_hook. No functional changes, just code
cleanup.

Suggested-by: Vlastimil Babka <vbabka@xxxxxxx>
Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
---
mm/slub.c | 34 +++++++++++++++++++++++++++++-----
1 file changed, 29 insertions(+), 5 deletions(-)

diff --git a/mm/slub.c b/mm/slub.c
index 4927edec6a8c..99d53190cfcf 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2033,11 +2033,18 @@ prepare_slab_obj_exts_hook(struct kmem_cache *s, gfp_t flags, void *p)
return slab_obj_exts(slab) + obj_to_index(s, slab, p);
}

+#ifdef CONFIG_MEM_ALLOC_PROFILING
+
+static inline void
+alloc_tagging_slab_alloc_hook(struct slabobj_ext *obj_exts, unsigned int size)
+{
+ alloc_tag_add(&obj_exts->ref, current->alloc_tag, size);
+}
+
static inline void
alloc_tagging_slab_free_hook(struct kmem_cache *s, struct slab *slab, void **p,
int objects)
{
-#ifdef CONFIG_MEM_ALLOC_PROFILING
struct slabobj_ext *obj_exts;
int i;

@@ -2053,9 +2060,23 @@ alloc_tagging_slab_free_hook(struct kmem_cache *s, struct slab *slab, void **p,

alloc_tag_sub(&obj_exts[off].ref, s->size);
}
-#endif
}

+#else /* CONFIG_MEM_ALLOC_PROFILING */
+
+static inline void
+alloc_tagging_slab_alloc_hook(struct slabobj_ext *obj_exts, unsigned int size)
+{
+}
+
+static inline void
+alloc_tagging_slab_free_hook(struct kmem_cache *s, struct slab *slab, void **p,
+ int objects)
+{
+}
+
+#endif /* CONFIG_MEM_ALLOC_PROFILING*/
+
#else /* CONFIG_SLAB_OBJ_EXT */

static int alloc_slab_obj_exts(struct slab *slab, struct kmem_cache *s,
@@ -2079,6 +2100,11 @@ prepare_slab_obj_exts_hook(struct kmem_cache *s, gfp_t flags, void *p)
return NULL;
}

+static inline void
+alloc_tagging_slab_alloc_hook(struct slabobj_ext *obj_exts, unsigned int size)
+{
+}
+
static inline void
alloc_tagging_slab_free_hook(struct kmem_cache *s, struct slab *slab, void **p,
int objects)
@@ -3944,7 +3970,6 @@ bool slab_post_alloc_hook(struct kmem_cache *s, struct list_lru *lru,
kmemleak_alloc_recursive(p[i], s->object_size, 1,
s->flags, init_flags);
kmsan_slab_alloc(s, p[i], init_flags);
-#ifdef CONFIG_MEM_ALLOC_PROFILING
if (need_slab_obj_ext()) {
struct slabobj_ext *obj_exts;

@@ -3955,9 +3980,8 @@ bool slab_post_alloc_hook(struct kmem_cache *s, struct list_lru *lru,
* check should be added before alloc_tag_add().
*/
if (likely(obj_exts))
- alloc_tag_add(&obj_exts->ref, current->alloc_tag, s->size);
+ alloc_tagging_slab_alloc_hook(obj_exts, s->size);
}
-#endif
}

return memcg_slab_post_alloc_hook(s, lru, flags, size, p);

base-commit: e9d22f7a6655941fc8b2b942ed354ec780936b3e
--
2.45.2.803.g4e1b14247a-goog