From: Vlastimil Babka <vbabka@xxxxxxx>
Subject: mm, slub: remove slub_memcg_sysfs boot param and CONFIG_SLUB_MEMCG_SYSFS_ON
The boot param and config determine the value of memcg_sysfs_enabled,
which is unused since commit 10befea91b61 ("mm: memcg/slab: use a single
set of kmem_caches for all allocations") as there are no per-memcg kmem
caches anymore.
Link: https://lkml.kernel.org/r/20210127124745.7928-1-vbabka@xxxxxxx
Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx>
Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
Acked-by: Roman Gushchin <guro@xxxxxx>
Acked-by: David Rientjes <rientjes@xxxxxxxxxx>
Reviewed-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: Pekka Enberg <penberg@xxxxxxxxxx>
Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
Documentation/admin-guide/kernel-parameters.txt | 8 -------
init/Kconfig | 14 ------------
mm/slub.c | 16 --------------
3 files changed, 38 deletions(-)
--- a/Documentation/admin-guide/kernel-parameters.txt~mm-slub-remove-slub_memcg_sysfs-boot-param-and-config_slub_memcg_sysfs_on
+++ a/Documentation/admin-guide/kernel-parameters.txt
@@ -4899,14 +4899,6 @@
last alloc / free. For more information see
Documentation/vm/slub.rst.
- slub_memcg_sysfs= [MM, SLUB]
- Determines whether to enable sysfs directories for
- memory cgroup sub-caches. 1 to enable, 0 to disable.
- The default is determined by CONFIG_SLUB_MEMCG_SYSFS_ON.
- Enabling this can lead to a very high number of debug
- directories and files being created under
- /sys/kernel/slub.
-
slub_max_order= [MM, SLUB]
Determines the maximum allowed order for slabs.
A high setting may cause OOMs due to memory
--- a/init/Kconfig~mm-slub-remove-slub_memcg_sysfs-boot-param-and-config_slub_memcg_sysfs_on
+++ a/init/Kconfig
@@ -1861,20 +1861,6 @@ config SLUB_DEBUG
SLUB sysfs support. /sys/slab will not exist and there will be
no support for cache validation etc.
-config SLUB_MEMCG_SYSFS_ON
- default n
- bool "Enable memcg SLUB sysfs support by default" if EXPERT
- depends on SLUB && SYSFS && MEMCG
- help
- SLUB creates a directory under /sys/kernel/slab for each
- allocation cache to host info and debug files. If memory
- cgroup is enabled, each cache can have per memory cgroup
- caches. SLUB can create the same sysfs directories for these
- caches under /sys/kernel/slab/CACHE/cgroup but it can lead
- to a very high number of debug files being created. This is
- controlled by slub_memcg_sysfs boot parameter and this
- config option determines the parameter's default value.
-
config COMPAT_BRK
bool "Disable heap randomization"
default y
--- a/mm/slub.c~mm-slub-remove-slub_memcg_sysfs-boot-param-and-config_slub_memcg_sysfs_on
+++ a/mm/slub.c
@@ -4943,22 +4943,6 @@ enum slab_stat_type {
#define SO_OBJECTS (1 << SL_OBJECTS)
#define SO_TOTAL (1 << SL_TOTAL)
-#ifdef CONFIG_MEMCG
-static bool memcg_sysfs_enabled = IS_ENABLED(CONFIG_SLUB_MEMCG_SYSFS_ON);
-
-static int __init setup_slub_memcg_sysfs(char *str)
-{
- int v;
-
- if (get_option(&str, &v) > 0)
- memcg_sysfs_enabled = v;
-
- return 1;
-}
-
-__setup("slub_memcg_sysfs=", setup_slub_memcg_sysfs);
-#endif
-
static ssize_t show_slab_objects(struct kmem_cache *s,
char *buf, unsigned long flags)
{
_
