Merge branch 'for-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq

Pull workqueue updates from Tejun Heo:
 "rcu_work addition and a couple trivial changes"

* 'for-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: remove the comment about the old manager_arb mutex
  workqueue: fix the comments of nr_idle
  fs/aio: Use rcu_work instead of explicit rcu and work item
  cgroup: Use rcu_work instead of explicit rcu and work item
  RCU, workqueue: Implement rcu_work

1 files changed, 23 insertions, 0 deletions

diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
index 0c3301421c57..39a0e215022a 100644
--- a/include/linux/workqueue.h
+++ b/include/linux/workqueue.h
@@ -13,6 +13,7 @@
 #include <linux/threads.h>
 #include <linux/atomic.h>
 #include <linux/cpumask.h>
+#include <linux/rcupdate.h>
 
 struct workqueue_struct;
 
@@ -120,6 +121,14 @@ struct delayed_work {
         int cpu;
 };
 
+struct rcu_work {
+        struct work_struct work;
+        struct rcu_head rcu;
+
+        /* target workqueue ->rcu uses to queue ->work */
+        struct workqueue_struct *wq;
+};
+
 /**
  * struct workqueue_attrs - A struct for workqueue attributes.
  *
@@ -151,6 +160,11 @@ static inline struct delayed_work *to_delayed_work(struct work_struct *work)
         return container_of(work, struct delayed_work, work);
 }
 
+static inline struct rcu_work *to_rcu_work(struct work_struct *work)
+{
+        return container_of(work, struct rcu_work, work);
+}
+
 struct execute_work {
         struct work_struct work;
 };
@@ -266,6 +280,12 @@ static inline unsigned int work_static(struct work_struct *work) { return 0; }
 #define INIT_DEFERRABLE_WORK_ONSTACK(_work, _func)                      \
         __INIT_DELAYED_WORK_ONSTACK(_work, _func, TIMER_DEFERRABLE)
 
+#define INIT_RCU_WORK(_work, _func)                                     \
+        INIT_WORK(&(_work)->work, (_func))
+
+#define INIT_RCU_WORK_ONSTACK(_work, _func)                             \
+        INIT_WORK_ONSTACK(&(_work)->work, (_func))
+
 /**
  * work_pending - Find out whether a work item is currently pending
  * @work: The work item in question
@@ -447,6 +467,7 @@ extern bool queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
                         struct delayed_work *work, unsigned long delay);
 extern bool mod_delayed_work_on(int cpu, struct workqueue_struct *wq,
                         struct delayed_work *dwork, unsigned long delay);
+extern bool queue_rcu_work(struct workqueue_struct *wq, struct rcu_work *rwork);
 
 extern void flush_workqueue(struct workqueue_struct *wq);
 extern void drain_workqueue(struct workqueue_struct *wq);
@@ -462,6 +483,8 @@ extern bool flush_delayed_work(struct delayed_work *dwork);
 extern bool cancel_delayed_work(struct delayed_work *dwork);
 extern bool cancel_delayed_work_sync(struct delayed_work *dwork);
 
+extern bool flush_rcu_work(struct rcu_work *rwork);
+
 extern void workqueue_set_max_active(struct workqueue_struct *wq,
                                      int max_active);
 extern struct work_struct *current_work(void);