From: Miaohe Lin <linmiaohe@xxxxxxxxxx> Subject: mm/mempool: add 'else' to split mutually exclusive case Add else to split mutually exclusive case and avoid some unnecessary check. It doesn't seem to change code generation (compiler is smart), but I think it helps readability. [akpm@xxxxxxxxxxxxxxxxxxxx: fix comment location] Link: https://lkml.kernel.org/r/20200924111641.28922-1-linmiaohe@xxxxxxxxxx Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/mempool.c | 18 ++++++++---------- 1 file changed, 8 insertions(+), 10 deletions(-) --- a/mm/mempool.c~mm-mempool-add-else-to-split-mutually-exclusive-case +++ a/mm/mempool.c @@ -58,11 +58,10 @@ static void __check_element(mempool_t *p static void check_element(mempool_t *pool, void *element) { /* Mempools backed by slab allocator */ - if (pool->free == mempool_free_slab || pool->free == mempool_kfree) + if (pool->free == mempool_free_slab || pool->free == mempool_kfree) { __check_element(pool, element, ksize(element)); - - /* Mempools backed by page allocator */ - if (pool->free == mempool_free_pages) { + } else if (pool->free == mempool_free_pages) { + /* Mempools backed by page allocator */ int order = (int)(long)pool->pool_data; void *addr = kmap_atomic((struct page *)element); @@ -82,11 +81,10 @@ static void __poison_element(void *eleme static void poison_element(mempool_t *pool, void *element) { /* Mempools backed by slab allocator */ - if (pool->alloc == mempool_alloc_slab || pool->alloc == mempool_kmalloc) + if (pool->alloc == mempool_alloc_slab || pool->alloc == mempool_kmalloc) { __poison_element(element, ksize(element)); - - /* Mempools backed by page allocator */ - if (pool->alloc == mempool_alloc_pages) { + } else if (pool->alloc == mempool_alloc_pages) { + /* Mempools backed by page allocator */ int order = (int)(long)pool->pool_data; void *addr = kmap_atomic((struct page *)element); @@ -107,7 +105,7 @@ static __always_inline void kasan_poison { if (pool->alloc == mempool_alloc_slab || pool->alloc == mempool_kmalloc) kasan_poison_kfree(element, _RET_IP_); - if (pool->alloc == mempool_alloc_pages) + else if (pool->alloc == mempool_alloc_pages) kasan_free_pages(element, (unsigned long)pool->pool_data); } @@ -115,7 +113,7 @@ static void kasan_unpoison_element(mempo { if (pool->alloc == mempool_alloc_slab || pool->alloc == mempool_kmalloc) kasan_unpoison_slab(element); - if (pool->alloc == mempool_alloc_pages) + else if (pool->alloc == mempool_alloc_pages) kasan_alloc_pages(element, (unsigned long)pool->pool_data); } _
