mirrors/linux
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2025-12-27 13:30:45 -05:00
Code Issues Packages Projects Releases Wiki Activity

mm/slab: simplify SLAB_* flag handling

Browse Source 
SLUB is the only remaining allocator. We can therefore get rid of
the logic for allocator-specific flags:

* Merge SLAB_CACHE_FLAGS into SLAB_CORE_FLAGS.

* Remove CACHE_CREATE_MASK and instead mask out SLAB_DEBUG_FLAGS if
  !CONFIG_SLUB_DEBUG. SLAB_DEBUG_FLAGS is now defined
  unconditionally (no impact on existing code, which ignores it if
  !CONFIG_SLUB_DEBUG).

* Define SLAB_FLAGS_PERMITTED in terms of SLAB_CORE_FLAGS and
  SLAB_DEBUG_FLAGS (no functional change).

While at it also remove misleading comments that suggest that
multiple allocators are available.

Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
This commit is contained in:
Kevin Brodsky
2025-01-24 16:48:58 +00:00
committed by Vlastimil Babka
parent dfd3df31c9
commit 12f4888c9d
2 changed files with 7 additions and 36 deletions
Download Patch File Download Diff File Expand all files Collapse all files

32
mm/slab.h
View File

@@ -457,39 +457,17 @@ static inline bool is_kmalloc_normal(struct kmem_cache *s)
return !(s->flags & (SLAB_CACHE_DMA|SLAB_ACCOUNT|SLAB_RECLAIM_ACCOUNT));
}
/* Legal flag mask for kmem_cache_create(), for various configurations */
#define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | \
SLAB_CACHE_DMA32 | SLAB_PANIC | \
SLAB_TYPESAFE_BY_RCU | SLAB_DEBUG_OBJECTS )
SLAB_TYPESAFE_BY_RCU | SLAB_DEBUG_OBJECTS | \
SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \
SLAB_TEMPORARY | SLAB_ACCOUNT | \
SLAB_NO_USER_FLAGS | SLAB_KMALLOC | SLAB_NO_MERGE)
#ifdef CONFIG_SLUB_DEBUG
#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
SLAB_TRACE | SLAB_CONSISTENCY_CHECKS)
#else
#define SLAB_DEBUG_FLAGS (0)
#endif
#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \
SLAB_TEMPORARY | SLAB_ACCOUNT | \
SLAB_NO_USER_FLAGS | SLAB_KMALLOC | SLAB_NO_MERGE)
/* Common flags available with current configuration */
#define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS)
/* Common flags permitted for kmem_cache_create */
#define SLAB_FLAGS_PERMITTED (SLAB_CORE_FLAGS | \
SLAB_RED_ZONE | \
SLAB_POISON | \
SLAB_STORE_USER | \
SLAB_TRACE | \
SLAB_CONSISTENCY_CHECKS | \
SLAB_NOLEAKTRACE | \
SLAB_RECLAIM_ACCOUNT | \
SLAB_TEMPORARY | \
SLAB_ACCOUNT | \
SLAB_KMALLOC | \
SLAB_NO_MERGE | \
SLAB_NO_USER_FLAGS)
#define SLAB_FLAGS_PERMITTED (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS)
bool __kmem_cache_empty(struct kmem_cache *);
int __kmem_cache_shutdown(struct kmem_cache *);

11
mm/slab_common.c
View File

@@ -298,6 +298,8 @@ struct kmem_cache *__kmem_cache_create_args(const char *name,
static_branch_enable(&slub_debug_enabled);
if (flags & SLAB_STORE_USER)
stack_depot_init();
#else
flags &= ~SLAB_DEBUG_FLAGS;
#endif
mutex_lock(&slab_mutex);
@@ -307,20 +309,11 @@ struct kmem_cache *__kmem_cache_create_args(const char *name,
goto out_unlock;
}
/* Refuse requests with allocator specific flags */
if (flags & ~SLAB_FLAGS_PERMITTED) {
err = -EINVAL;
goto out_unlock;
}
/*
* Some allocators will constraint the set of valid flags to a subset
* of all flags. We expect them to define CACHE_CREATE_MASK in this
* case, and we'll just provide them with a sanitized version of the
* passed flags.
*/
flags &= CACHE_CREATE_MASK;
/* Fail closed on bad usersize of useroffset values. */
if (!IS_ENABLED(CONFIG_HARDENED_USERCOPY) ||
WARN_ON(!args->usersize && args->useroffset) ||