From 1233da4943a9a0e334748490225ae10b0d770c0a Mon Sep 17 00:00:00 2001
From: Wilco Dijkstra <wilco.dijkstra@arm.com>
Date: Thu, 20 Mar 2025 16:36:52 +0000
Subject: [PATCH] malloc: Use __always_inline for simple functions

Use __always_inline for small helper functions that are critical for
performance.  This ensures inlining always happens when expected.
Performance of bench-malloc-simple improves by 0.6% on average on
Neoverse V2.

Reviewed-by: DJ Delorie <dj@redhat.com>
---
 malloc/arena.c  | 12 ++++++------
 malloc/malloc.c | 10 +++++-----
 2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/malloc/arena.c b/malloc/arena.c
index 405ae829c0..5672c699aa 100644
--- a/malloc/arena.c
+++ b/malloc/arena.c
@@ -43,14 +43,14 @@
 /* HEAP_MAX_SIZE should be larger than the huge page size, otherwise heaps will
    use not huge pages.  It is a constant so arena_for_chunk() is efficient.  */
 
-static inline size_t
+static __always_inline size_t
 heap_min_size (void)
 {
   return mp_.hp_pagesize == 0 || mp_.hp_pagesize > HEAP_MAX_SIZE
 	  ? HEAP_MIN_SIZE : mp_.hp_pagesize;
 }
 
-static inline size_t
+static __always_inline size_t
 heap_max_size (void)
 {
   return HEAP_MAX_SIZE;
@@ -141,14 +141,14 @@ static bool __malloc_initialized = false;
 
 /* find the heap and corresponding arena for a given ptr */
 
-static inline heap_info *
+static __always_inline heap_info *
 heap_for_ptr (void *ptr)
 {
   size_t max_size = heap_max_size ();
   return PTR_ALIGN_DOWN (ptr, max_size);
 }
 
-static inline struct malloc_state *
+static __always_inline struct malloc_state *
 arena_for_chunk (mchunkptr ptr)
 {
   return chunk_main_arena (ptr) ? &main_arena : heap_for_ptr (ptr)->ar_ptr;
@@ -232,8 +232,8 @@ __malloc_fork_unlock_child (void)
 }
 
 #define TUNABLE_CALLBACK_FNDECL(__name, __type) \
-static inline int do_ ## __name (__type value);				      \
-static void									      \
+static __always_inline int do_ ## __name (__type value);		      \
+static void								      \
 TUNABLE_CALLBACK (__name) (tunable_val_t *valp)				      \
 {									      \
   __type value = (__type) (valp)->numval;				      \
diff --git a/malloc/malloc.c b/malloc/malloc.c
index 0811061e46..7e4c139938 100644
--- a/malloc/malloc.c
+++ b/malloc/malloc.c
@@ -1322,7 +1322,7 @@ nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    value is less than PTRDIFF_T.  Returns the requested size or
    MINSIZE in case the value is less than MINSIZE, or 0 if any of the
    previous checks fail.  */
-static inline size_t
+static __always_inline size_t
 checked_request2size (size_t req) __nonnull (1)
 {
   if (__glibc_unlikely (req > PTRDIFF_MAX))
@@ -1782,7 +1782,7 @@ static uint8_t global_max_fast;
   global_max_fast = (((size_t) (s) <= MALLOC_ALIGN_MASK - SIZE_SZ)	\
                      ? MIN_CHUNK_SIZE / 2 : ((s + SIZE_SZ) & ~MALLOC_ALIGN_MASK))
 
-static inline INTERNAL_SIZE_T
+static __always_inline INTERNAL_SIZE_T
 get_max_fast (void)
 {
   /* Tell the GCC optimizers that global_max_fast is never larger
@@ -3245,7 +3245,7 @@ tcache_double_free_verify (tcache_entry *e, size_t tc_idx)
 
 /* Try to free chunk to the tcache, if success return true.
    Caller must ensure that chunk and size are valid.  */
-static inline bool
+static __always_inline bool
 tcache_free (mchunkptr p, INTERNAL_SIZE_T size)
 {
   bool done = false;
@@ -4553,7 +4553,7 @@ _int_malloc (mstate av, size_t bytes)
    ------------------------------ free ------------------------------
  */
 
-static inline void
+static __always_inline void
 _int_free_check (mstate av, mchunkptr p, INTERNAL_SIZE_T size)
 {
   /* Little security check which won't hurt performance: the
@@ -4687,7 +4687,7 @@ _int_free_chunk (mstate av, mchunkptr p, INTERNAL_SIZE_T size, int have_lock)
    P has already been locked.  It will perform sanity check, then try the
    fast path to free into tcache.  If the attempt not success, free the
    chunk to arena.  */
-static inline void
+static __always_inline void
 _int_free (mstate av, mchunkptr p, int have_lock)
 {
   INTERNAL_SIZE_T size;        /* its size */