From 154036a3b3f39cb17fc65511011f4c4024846e91 Mon Sep 17 00:00:00 2001 From: Andrey Konovalov Date: Thu, 28 Apr 2022 17:59:40 +0200 Subject: [PATCH] mm: slab: fix comment for __assume_kmalloc_alignment The comment next to the __assume_kmalloc_alignment definition is not precise: kmalloc relies on kmem_cache_alloc, so kmalloc technically returns pointers aligned to both ARCH_KMALLOC_MINALIGN and ARCH_SLAB_MINALIGN, not only to ARCH_KMALLOC_MINALIGN. (See create_kmalloc_cache()->create_boot_cache()->calculate_alignment() for SLAB and SLUB and __do_kmalloc_node() for SLOB.) Clarify the comment. The assumption specified by __assume_kmalloc_alignment is still correct, although it can be made stronger. I'll leave this to a separate patch. Signed-off-by: Andrey Konovalov Acked-by: David Rientjes Signed-off-by: Vlastimil Babka Link: https://lore.kernel.org/r/84d8142747230f2015eaf9705ee7c2e1a9f56596.1651161548.git.andreyknvl@google.com --- include/linux/slab.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/include/linux/slab.h b/include/linux/slab.h index 8c090599fc21..58bb9392775d 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -217,9 +217,9 @@ void kmem_dump_obj(void *object); #endif /* - * kmalloc and friends return ARCH_KMALLOC_MINALIGN aligned - * pointers. kmem_cache_alloc and friends return ARCH_SLAB_MINALIGN - * aligned pointers. + * kmem_cache_alloc and friends return pointers aligned to ARCH_SLAB_MINALIGN. + * kmalloc and friends return pointers aligned to both ARCH_KMALLOC_MINALIGN + * and ARCH_SLAB_MINALIGN, but here we only assume the former alignment. */ #define __assume_kmalloc_alignment __assume_aligned(ARCH_KMALLOC_MINALIGN) #define __assume_slab_alignment __assume_aligned(ARCH_SLAB_MINALIGN) -- 2.34.1