[PATCH v3 07/35] mm/slab: introduce SLAB_NO_OBJ_EXT to avoid obj_ext creation
From: Suren Baghdasaryan <surenb@google.com>
Date: 2024-02-12 21:39:48
Also in:
cgroups, linux-doc, linux-fsdevel, linux-iommu, linux-mm, linux-modules, lkml
Subsystem:
memory management, slab allocator, the rest · Maintainers:
Andrew Morton, Vlastimil Babka, Harry Yoo, Linus Torvalds
Slab extension objects can't be allocated before slab infrastructure is initialized. Some caches, like kmem_cache and kmem_cache_node, are created before slab infrastructure is initialized. Objects from these caches can't have extension objects. Introduce SLAB_NO_OBJ_EXT slab flag to mark these caches and avoid creating extensions for objects allocated from these slabs. Signed-off-by: Suren Baghdasaryan <surenb@google.com> --- include/linux/slab.h | 7 +++++++ mm/slub.c | 5 +++-- 2 files changed, 10 insertions(+), 2 deletions(-)
diff --git a/include/linux/slab.h b/include/linux/slab.h
index b5f5ee8308d0..3ac2fc830f0f 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h@@ -164,6 +164,13 @@ #endif #define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */ +#ifdef CONFIG_SLAB_OBJ_EXT +/* Slab created using create_boot_cache */ +#define SLAB_NO_OBJ_EXT ((slab_flags_t __force)0x20000000U) +#else +#define SLAB_NO_OBJ_EXT 0 +#endif + /* * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests. *
diff --git a/mm/slub.c b/mm/slub.c
index 1eb1050814aa..9fd96238ed39 100644
--- a/mm/slub.c
+++ b/mm/slub.c@@ -5650,7 +5650,8 @@ void __init kmem_cache_init(void) node_set(node, slab_nodes); create_boot_cache(kmem_cache_node, "kmem_cache_node", - sizeof(struct kmem_cache_node), SLAB_HWCACHE_ALIGN, 0, 0); + sizeof(struct kmem_cache_node), + SLAB_HWCACHE_ALIGN | SLAB_NO_OBJ_EXT, 0, 0); hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI);
@@ -5660,7 +5661,7 @@ void __init kmem_cache_init(void) create_boot_cache(kmem_cache, "kmem_cache", offsetof(struct kmem_cache, node) + nr_node_ids * sizeof(struct kmem_cache_node *), - SLAB_HWCACHE_ALIGN, 0, 0); + SLAB_HWCACHE_ALIGN | SLAB_NO_OBJ_EXT, 0, 0); kmem_cache = bootstrap(&boot_kmem_cache); kmem_cache_node = bootstrap(&boot_kmem_cache_node);
--
2.43.0.687.g38aa6559b0-goog