malloc: Avoid func call for tcache quick path in free()

Tcache is an important optimzation to accelerate memory free(), things
within this code path should be kept as simple as possible. This commit
try to remove the function call when free() invokes tcache code path by
inlining _int_free().

Result of bench-malloc-thread benchmark

Test Platform: Xeon-8380
Ratio: New / Original time_per_iteration (Lower is Better)

Threads#   | Ratio
-----------|------
1 thread   | 0.879
4 threads  | 0.874

The performance data shows it can improve bench-malloc-thread benchmark
by ~12% in both single thread and multi-thread scenario.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

diff --git a/malloc/malloc.c b/malloc/malloc.c
index 32dbc272a82982001bca00cc33f9c700f96dde8c..81ddd2c3a8ad14eb11cc3199d2a2922e964e617c 100644 (file)
--- a/malloc/malloc.c
+++ b/malloc/malloc.c
@@ -4677,7 +4677,7 @@ _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 void
+static inline void
 _int_free (mstate av, mchunkptr p, int have_lock)
 {
   INTERNAL_SIZE_T size;        /* its size */