mm, slab: add kerneldocs for common SLAB_ flags

We have many SLAB_ flags but many are used only internally, by kunit
tests or debugging subsystems cooperating with slab, or are set
according to slab_debug boot parameter.

Create kerneldocs for the commonly used flags that may be passed to
kmem_cache_create(). SLAB_TYPESAFE_BY_RCU already had a detailed
description, so turn it to a kerneldoc. Add some details for
SLAB_ACCOUNT, SLAB_RECLAIM_ACCOUNT and SLAB_HWCACHE_ALIGN. Reference
them from the __kmem_cache_create_args() kerneldoc.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>

1 files changed, 13 insertions, 1 deletions

diff --git a/mm/slab_common.c b/mm/slab_common.c
index 9e22d1266f6a..62878edb0a81 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -254,11 +254,23 @@ out:
  * @object_size: The size of objects to be created in this cache.
  * @args: Additional arguments for the cache creation (see
  *        &struct kmem_cache_args).
- * @flags: See %SLAB_* flags for an explanation of individual @flags.
+ * @flags: See the desriptions of individual flags. The common ones are listed
+ *         in the description below.
  *
  * Not to be called directly, use the kmem_cache_create() wrapper with the same
  * parameters.
  *
+ * Commonly used @flags:
+ *
+ * &SLAB_ACCOUNT - Account allocations to memcg.
+ *
+ * &SLAB_HWCACHE_ALIGN - Align objects on cache line boundaries.
+ *
+ * &SLAB_RECLAIM_ACCOUNT - Objects are reclaimable.
+ *
+ * &SLAB_TYPESAFE_BY_RCU - Slab page (not individual objects) freeing delayed
+ * by a grace period - see the full description before using.
+ *
  * Context: Cannot be called within a interrupt, but can be interrupted.
  *
  * Return: a pointer to the cache on success, NULL on failure.