[PATCH 1/2] Consolidate heap in memalign when alignment is large.

[Ondřej Bílka]

Hi,

I looked how deduplicate malloc code. Funcions valloc/pvalloc should be
implemented by calling memalign, only difference is that they call heap
consolidation.

If consolidation is useful then memalign would benefit when user passes
page size alignments. Otherwise we should delete consolidation from
valloc.

Which alternative is better?

	* malloc/malloc.c (__libc_memalign): Call heap consolidation
	when alignment is multiple of page size.

diff --git a/malloc/malloc.c b/malloc/malloc.c
index 897c43a..29a5488 100644
--- a/malloc/malloc.c
+++ b/malloc/malloc.c
@@ -3005,6 +3005,9 @@ __libc_memalign(size_t alignment, size_t bytes)
   mstate ar_ptr;
   void *p;
 
+  if(__malloc_initialized < 0)
+    ptmalloc_init();
+
   void *(*hook) (size_t, size_t, const void *) =
     force_reg (__memalign_hook);
   if (__builtin_expect (hook != NULL, 0))
@@ -3034,6 +3037,9 @@ __libc_memalign(size_t alignment, size_t bytes)
   arena_get(ar_ptr, bytes + alignment + MINSIZE);
   if(!ar_ptr)
     return 0;
+
+  if (have_fastchunks(ar_ptr) && alignment >= GLRO(dl_pagesize))
+    malloc_consolidate(av);
   p = _int_memalign(ar_ptr, alignment, bytes);
   if(!p) {
     LIBC_PROBE (memory_memalign_retry, 2, bytes, alignment);