[PATCH 2/2] Don't allocate another header when merging chunks

Torbjörn SVENSSON torbjorn.svensson@foss.st.com
Tue Aug 30 13:56:26 GMT 2022


In the nano version of malloc, when the last chunk is to be extended,
there is no need to acount for the header again as it's already taken
into account in the overall "alloc_size" at the beginning of the
function.

Contributed by STMicroelectronics

Signed-off-by: Torbjörn SVENSSON <torbjorn.svensson@foss.st.com>
---
 newlib/libc/stdlib/nano-mallocr.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/newlib/libc/stdlib/nano-mallocr.c b/newlib/libc/stdlib/nano-mallocr.c
index 43eb20e07..b2273ba60 100644
--- a/newlib/libc/stdlib/nano-mallocr.c
+++ b/newlib/libc/stdlib/nano-mallocr.c
@@ -328,10 +328,6 @@ void * nano_malloc(RARG malloc_size_t s)
                /* The last free item has the heap end as neighbour.
                 * Let's ask for a smaller amount and merge */
                alloc_size -= p->size;
-               alloc_size = ALIGN_SIZE(alloc_size, CHUNK_ALIGN); /* size of aligned data load */
-               alloc_size += MALLOC_PADDING; /* padding */
-               alloc_size += CHUNK_OFFSET; /* size of chunk head */
-               alloc_size = MAX(alloc_size, MALLOC_MINCHUNK);
 
                if (sbrk_aligned(RCALL alloc_size) != (void *)-1)
                {
-- 
2.25.1



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