[PATCH v4 1/2] mm: introduce helper to check slub_debug_enabled

From: yee.lee
Date: Fri Jul 02 2021 - 04:54:10 EST


From: Marco Elver <elver@xxxxxxxxxx>

Introduce a helper to check slub_debug_enabled, so that we can confine
the use of #ifdef to the definition of the slub_debug_enabled_unlikely()
helper.

---

Signed-off-by: Marco Elver <elver@xxxxxxxxxx>
Signed-off-by: Yee Lee <yee.lee@xxxxxxxxxxxx>

---
mm/slab.h | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/mm/slab.h b/mm/slab.h
index 7b60ef2f32c3..a11126afe24c 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -216,10 +216,18 @@ DECLARE_STATIC_KEY_FALSE(slub_debug_enabled);
#endif
extern void print_tracking(struct kmem_cache *s, void *object);
long validate_slab_cache(struct kmem_cache *s);
+static inline bool slub_debug_enabled_unlikely(void)
+{
+ return static_branch_unlikely(&slub_debug_enabled);
+}
#else
static inline void print_tracking(struct kmem_cache *s, void *object)
{
}
+static inline bool slub_debug_enabled_unlikely(void)
+{
+ return false;
+}
#endif

/*
@@ -229,11 +237,10 @@ static inline void print_tracking(struct kmem_cache *s, void *object)
*/
static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t flags)
{
-#ifdef CONFIG_SLUB_DEBUG
- VM_WARN_ON_ONCE(!(flags & SLAB_DEBUG_FLAGS));
- if (static_branch_unlikely(&slub_debug_enabled))
+ if (IS_ENABLED(CONFIG_SLUB_DEBUG))
+ VM_WARN_ON_ONCE(!(flags & SLAB_DEBUG_FLAGS));
+ if (slub_debug_enabled_unlikely())
return s->flags & flags;
-#endif
return false;
}

--
2.18.0