When memory allocation profiling is disabled there is no need to update
current->alloc_tag and these manipulations add unnecessary overhead. Fix
the overhead by skipping these extra updates.
Fixes: b951aaff5035 ("mm: enable page allocation tagging")
Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
---
include/linux/alloc_tag.h | 11 ++++++++---
lib/alloc_tag.c | 2 ++
2 files changed, 10 insertions(+), 3 deletions(-)
diff --git a/include/linux/alloc_tag.h b/include/linux/alloc_tag.h
index 0bbbe537c5f9..a946e0203e6d 100644
--- a/include/linux/alloc_tag.h
+++ b/include/linux/alloc_tag.h
@@ -224,9 +224,14 @@ static inline void alloc_tag_sub(union codetag_ref *ref, size_t bytes) {}
#define alloc_hooks_tag(_tag, _do_alloc) \
({ \
- struct alloc_tag * __maybe_unused _old = alloc_tag_save(_tag); \
- typeof(_do_alloc) _res = _do_alloc; \
- alloc_tag_restore(_tag, _old); \
+ typeof(_do_alloc) _res; \
+ if (mem_alloc_profiling_enabled()) { \
+ struct alloc_tag * __maybe_unused _old; \
+ _old = alloc_tag_save(_tag); \
+ _res = _do_alloc; \
+ alloc_tag_restore(_tag, _old); \
+ } else \
+ _res = _do_alloc; \
_res; \
})
diff --git a/lib/alloc_tag.c b/lib/alloc_tag.c
index 7dcebf118a3e..4c373f444eb1 100644
--- a/lib/alloc_tag.c
+++ b/lib/alloc_tag.c
@@ -29,6 +29,8 @@ EXPORT_SYMBOL(_shared_alloc_tag);
DEFINE_STATIC_KEY_MAYBE(CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT,
mem_alloc_profiling_key);
+EXPORT_SYMBOL(mem_alloc_profiling_key);
+
DEFINE_STATIC_KEY_FALSE(mem_profiling_compressed);
struct alloc_tag_kernel_section kernel_tags = { NULL, 0 };
base-commit: 431614f1580a03c1a653340c55ea76bd12a9403f
--
2.47.1.613.gc27f4b7a9f-goog
