Commit c64b95d3 authored by Vlastimil Babka's avatar Vlastimil Babka
Browse files

Merge branch 'slab/for-6.2/slub-sysfs' into slab/for-next 

- Two patches for SLUB's sysfs by Rasmus Villemoes to remove dead code
  and optimize boot time with late initialization.
- Allow SLUB's sysfs 'failslab' parameter to be runtime-controllable
  again as it can be both useful and safe, by Alexander Atanasov.
parents 14d3eb66 7c82b3b3

Documentation/mm/slub.rst

+2 −0
Original line number Diff line number Diff line
@@ -116,6 +116,8 @@ options from the ``slub_debug`` parameter translate to the following files:: 
	T	trace

	A	failslab



failslab file is writable, so writing 1 or 0 will enable or disable

the option at runtime. Write returns -EINVAL if cache is an alias.

Careful with tracing: It may spew out lots of information and never stop if

used on the wrong slab.

mm/slub.c

+16 −8
Original line number Diff line number Diff line
@@ -5575,7 +5575,21 @@ static ssize_t failslab_show(struct kmem_cache *s, char *buf) 
{

	return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_FAILSLAB));

}

SLAB_ATTR_RO(failslab);



static ssize_t failslab_store(struct kmem_cache *s, const char *buf,

				size_t length)

{

	if (s->refcount > 1)

		return -EINVAL;



	if (buf[0] == '1')

		WRITE_ONCE(s->flags, s->flags | SLAB_FAILSLAB);

	else

		WRITE_ONCE(s->flags, s->flags & ~SLAB_FAILSLAB);



	return length;

}

SLAB_ATTR(failslab);

#endif



static ssize_t shrink_show(struct kmem_cache *s, char *buf)
@@ -5909,11 +5923,6 @@ static int sysfs_slab_add(struct kmem_cache *s) 
	struct kset *kset = cache_kset(s);

	int unmergeable = slab_unmergeable(s);



	if (!kset) {

		kobject_init(&s->kobj, &slab_ktype);

		return 0;

	}



	if (!unmergeable && disable_higher_order_debug &&

			(slub_debug & DEBUG_METADATA_FLAGS))

		unmergeable = 1;
@@ -6043,8 +6052,7 @@ static int __init slab_sysfs_init(void) 
	mutex_unlock(&slab_mutex);

	return 0;

}



__initcall(slab_sysfs_init);

late_initcall(slab_sysfs_init);

#endif /* CONFIG_SYSFS */



#if defined(CONFIG_SLUB_DEBUG) && defined(CONFIG_DEBUG_FS)