console: Fix console name size mismatch

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / kernel / cgroup.c

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index b6b26faf1740d6d9d53ebd2942340b6709ef59c1..d0def7fc2848dd899281b2bb2527f05fa79ec7a9 100644 (file)
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -91,6 +91,14 @@ static DEFINE_MUTEX(cgroup_mutex);
 
 static DEFINE_MUTEX(cgroup_root_mutex);
 
+/*
+ * cgroup destruction makes heavy use of work items and there can be a lot
+ * of concurrent destructions.  Use a separate workqueue so that cgroup
+ * destruction work items don't end up filling up max_active of system_wq
+ * which may lead to deadlock.
+ */
+static struct workqueue_struct *cgroup_destroy_wq;
+
 /*
  * Generate an array of cgroup subsystem pointers. At boot time, this is
  * populated with the built in subsystems, and modular subsystems are
@@ -873,7 +881,7 @@ static void cgroup_free_rcu(struct rcu_head *head)
 {
        struct cgroup *cgrp = container_of(head, struct cgroup, rcu_head);
 
-       schedule_work(&cgrp->free_work);
+       queue_work(cgroup_destroy_wq, &cgrp->free_work);
 }
 
 static void cgroup_diput(struct dentry *dentry, struct inode *inode)
@@ -4686,6 +4694,22 @@ out:
        return err;
 }
 
+static int __init cgroup_wq_init(void)
+{
+       /*
+        * There isn't much point in executing destruction path in
+        * parallel.  Good chunk is serialized with cgroup_mutex anyway.
+        * Use 1 for @max_active.
+        *
+        * We would prefer to do this in cgroup_init() above, but that
+        * is called before init_workqueues(): so leave this until after.
+        */
+       cgroup_destroy_wq = alloc_workqueue("cgroup_destroy", 0, 1);
+       BUG_ON(!cgroup_destroy_wq);
+       return 0;
+}
+core_initcall(cgroup_wq_init);
+
 /*
  * proc_cgroup_show()
  *  - Print task's cgroup paths into seq_file, one line for each hierarchy
@@ -4996,7 +5020,7 @@ void __css_put(struct cgroup_subsys_state *css)
 
        v = css_unbias_refcnt(atomic_dec_return(&css->refcnt));
        if (v == 0)
-               schedule_work(&css->dput_work);
+               queue_work(cgroup_destroy_wq, &css->dput_work);
 }
 EXPORT_SYMBOL_GPL(__css_put);