| Message ID | 20200924111641.28922-1-linmiaohe@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] mm/mempool: Add 'else' to split mutually exclusive case | expand |
On Thu, 24 Sep 2020 07:16:41 -0400 Miaohe Lin <linmiaohe@huawei.com> wrote: > 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. > > ... > > --- a/mm/mempool.c > +++ b/mm/mempool.c > @@ -58,11 +58,10 @@ static void __check_element(mempool_t *pool, void *element, size_t size) > 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) { > int order = (int)(long)pool->pool_data; > void *addr = kmap_atomic((struct page *)element); > > @@ -82,11 +81,10 @@ static void __poison_element(void *element, size_t size) > 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) { > int order = (int)(long)pool->pool_data; > void *addr = kmap_atomic((struct page *)element); > OK, I guess. But the comments are now in the wrong place. --- a/mm/mempool.c~mm-mempool-add-else-to-split-mutually-exclusive-case-fix +++ a/mm/mempool.c @@ -60,8 +60,8 @@ static void check_element(mempool_t *poo /* Mempools backed by slab allocator */ if (pool->free == mempool_free_slab || pool->free == mempool_kfree) { __check_element(pool, element, ksize(element)); - /* Mempools backed by page allocator */ } 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); @@ -83,8 +83,8 @@ static void poison_element(mempool_t *po /* Mempools backed by slab allocator */ if (pool->alloc == mempool_alloc_slab || pool->alloc == mempool_kmalloc) { __poison_element(element, ksize(element)); - /* Mempools backed by page allocator */ } 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);
diff --git a/mm/mempool.c b/mm/mempool.c index 79bff63ecf27..95fa8e601730 100644 --- a/mm/mempool.c +++ b/mm/mempool.c @@ -58,11 +58,10 @@ static void __check_element(mempool_t *pool, void *element, size_t size) 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) { int order = (int)(long)pool->pool_data; void *addr = kmap_atomic((struct page *)element); @@ -82,11 +81,10 @@ static void __poison_element(void *element, size_t size) 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) { int order = (int)(long)pool->pool_data; void *addr = kmap_atomic((struct page *)element); @@ -107,7 +105,7 @@ static __always_inline void kasan_poison_element(mempool_t *pool, void *element) { 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(mempool_t *pool, void *element) { 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); }
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. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> --- mm/mempool.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-)