mm, sl[aou]b: Move kmem_cache_create mutex handling to common code
Move the mutex handling into the common kmem_cache_create()
function.
Then we can also move more checks out of SLAB's kmem_cache_create()
into the common code.
Reviewed-by: Glauber Costa <glommer@parallels.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
diff --git a/mm/slab_common.c b/mm/slab_common.c
index 50e1ff1..12637ce 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -11,7 +11,8 @@
#include <linux/memory.h>
#include <linux/compiler.h>
#include <linux/module.h>
-
+#include <linux/cpu.h>
+#include <linux/uaccess.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
#include <asm/page.h>
@@ -61,8 +62,46 @@
}
#endif
+ get_online_cpus();
+ mutex_lock(&slab_mutex);
+
+#ifdef CONFIG_DEBUG_VM
+ list_for_each_entry(s, &slab_caches, list) {
+ char tmp;
+ int res;
+
+ /*
+ * This happens when the module gets unloaded and doesn't
+ * destroy its slab cache and no-one else reuses the vmalloc
+ * area of the module. Print a warning.
+ */
+ res = probe_kernel_address(s->name, tmp);
+ if (res) {
+ printk(KERN_ERR
+ "Slab cache with size %d has lost its name\n",
+ s->object_size);
+ continue;
+ }
+
+ if (!strcmp(s->name, name)) {
+ printk(KERN_ERR "kmem_cache_create(%s): Cache name"
+ " already exists.\n",
+ name);
+ dump_stack();
+ s = NULL;
+ goto oops;
+ }
+ }
+
+ WARN_ON(strchr(name, ' ')); /* It confuses parsers */
+#endif
+
s = __kmem_cache_create(name, size, align, flags, ctor);
+oops:
+ mutex_unlock(&slab_mutex);
+ put_online_cpus();
+
#ifdef CONFIG_DEBUG_VM
out:
#endif