slab, slub, slob: convert slab_flags_t to 32-bit

struct kmem_cache::flags is "unsigned long" which is unnecessary on
64-bit as no flags are defined in the higher bits.

Switch the field to 32-bit and save some space on x86_64 until such
flags appear:

	add/remove: 0/0 grow/shrink: 0/107 up/down: 0/-657 (-657)
	function                                     old     new   delta
	sysfs_slab_add                               720     719      -1
				...
	check_object                                 699     676     -23

[[email protected]: fix printk warning]
Link: http://lkml.kernel.org/r/20171021100635.GA8287@avx2
Signed-off-by: Alexey Dobriyan <[email protected]>
Acked-by: Pekka Enberg <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Joonsoo Kim <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This commit is contained in:
Alexey Dobriyan 2017-11-15 17:32:21 -08:00 • committed by Linus Torvalds
commit 4fd0b46e89
4 changed files with 28 additions and 28 deletions

View file

@ -252,8 +252,8 @@ static void kmem_cache_node_init(struct kmem_cache_node *parent)
MAKE_LIST((cachep), (&(ptr)->slabs_free), slabs_free, nodeid); \
} while (0)
#define CFLGS_OBJFREELIST_SLAB ((slab_flags_t __force)0x40000000UL)
#define CFLGS_OFF_SLAB ((slab_flags_t __force)0x80000000UL)
#define CFLGS_OBJFREELIST_SLAB ((slab_flags_t __force)0x40000000U)
#define CFLGS_OFF_SLAB ((slab_flags_t __force)0x80000000U)
#define OBJFREELIST_SLAB(x) ((x)->flags & CFLGS_OBJFREELIST_SLAB)
#define OFF_SLAB(x) ((x)->flags & CFLGS_OFF_SLAB)