mm, sl[aou]b: Common definition for boot state of the slab allocators

All allocators have some sort of support for the bootstrap status.

Setup a common definition for the boot states and make all slab
allocators use that definition.

Reviewed-by: Glauber Costa <glommer@parallels.com>
Reviewed-by: Joonsoo Kim <js1304@gmail.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

1 files changed, 9 insertions, 0 deletions

diff --git a/mm/slab_common.c b/mm/slab_common.c
index 80412beb67cc..ca1aaf69a1f5 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -16,6 +16,10 @@
 #include <asm/tlbflush.h>
 #include <asm/page.h>
 
+#include "slab.h"
+
+enum slab_state slab_state;
+
 /*
  * kmem_cache_create - Create a cache.
  * @name: A string which is used in /proc/slabinfo to identify this cache.
@@ -66,3 +70,8 @@ out:
 	return s;
 }
 EXPORT_SYMBOL(kmem_cache_create);
+
+int slab_is_available(void)
+{
+	return slab_state >= UP;
+}