Merge branch 'akpm' (patches from Andrew)

Merge updates from Andrew Morton:

 - various misc bits

 - most of MM (quite a lot of MM material is awaiting the merge of
   linux-next dependencies)

 - kasan

 - printk updates

 - procfs updates

 - MAINTAINERS

 - /lib updates

 - checkpatch updates

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (123 commits)
  init: reduce rootwait polling interval time to 5ms
  binfmt_elf: use vmalloc() for allocation of vma_filesz
  checkpatch: don't emit unified-diff error for rename-only patches
  checkpatch: don't check c99 types like uint8_t under tools
  checkpatch: avoid multiple line dereferences
  checkpatch: don't check .pl files, improve absolute path commit log test
  scripts/checkpatch.pl: fix spelling
  checkpatch: don't try to get maintained status when --no-tree is given
  lib/ida: document locking requirements a bit better
  lib/rbtree.c: fix typo in comment of ____rb_erase_color
  lib/Kconfig.debug: make CONFIG_STRICT_DEVMEM depend on CONFIG_DEVMEM
  MAINTAINERS: add drm and drm/i915 irc channels
  MAINTAINERS: add "C:" for URI for chat where developers hang out
  MAINTAINERS: add drm and drm/i915 bug filing info
  MAINTAINERS: add "B:" for URI where to file bugs
  get_maintainer: look for arbitrary letter prefixes in sections
  printk: add Kconfig option to set default console loglevel
  printk/sound: handle more message headers
  printk/btrfs: handle more message headers
  printk/kdb: handle more message headers
  ...

1 files changed, 14 insertions, 1 deletions

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 6c2043509fb5..175ec51c346d 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2145,6 +2145,8 @@ struct memcg_kmem_cache_create_work {
 	struct work_struct work;
 };
 
+static struct workqueue_struct *memcg_kmem_cache_create_wq;
+
 static void memcg_kmem_cache_create_func(struct work_struct *w)
 {
 	struct memcg_kmem_cache_create_work *cw =
@@ -2176,7 +2178,7 @@ static void __memcg_schedule_kmem_cache_create(struct mem_cgroup *memcg,
 	cw->cachep = cachep;
 	INIT_WORK(&cw->work, memcg_kmem_cache_create_func);
 
-	schedule_work(&cw->work);
+	queue_work(memcg_kmem_cache_create_wq, &cw->work);
 }
 
 static void memcg_schedule_kmem_cache_create(struct mem_cgroup *memcg,
@@ -5774,6 +5776,17 @@ static int __init mem_cgroup_init(void)
 {
 	int cpu, node;
 
+#ifndef CONFIG_SLOB
+	/*
+	 * Kmem cache creation is mostly done with the slab_mutex held,
+	 * so use a special workqueue to avoid stalling all worker
+	 * threads in case lots of cgroups are created simultaneously.
+	 */
+	memcg_kmem_cache_create_wq =
+		alloc_ordered_workqueue("memcg_kmem_cache_create", 0);
+	BUG_ON(!memcg_kmem_cache_create_wq);
+#endif
+
 	cpuhp_setup_state_nocalls(CPUHP_MM_MEMCQ_DEAD, "mm/memctrl:dead", NULL,
 				  memcg_hotplug_cpu_dead);