This will be used in kfree_rcu() later to make it do call_rcu() lazily.
Signed-off-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>
---
include/linux/workqueue.h | 1 +
kernel/workqueue.c | 25 +++++++++++++++++++++++++
2 files changed, 26 insertions(+)
diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
index 7fee9b6cfede..2678a6b5b3f3 100644
--- a/include/linux/workqueue.h
+++ b/include/linux/workqueue.h
@@ -444,6 +444,7 @@ extern bool queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
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 bool queue_rcu_work_lazy(struct workqueue_struct *wq, struct rcu_work *rwork);
extern void flush_workqueue(struct workqueue_struct *wq);
extern void drain_workqueue(struct workqueue_struct *wq);
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 33f1106b4f99..9444949cc148 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -1796,6 +1796,31 @@ bool queue_rcu_work(struct workqueue_struct *wq, struct rcu_work *rwork)
}
EXPORT_SYMBOL(queue_rcu_work);
+/**
+ * queue_rcu_work_lazy - queue work after a RCU grace period
+ * @wq: workqueue to use
+ * @rwork: work to queue
+ *
+ * Return: %false if @rwork was already pending, %true otherwise. Note
+ * that a full RCU grace period is guaranteed only after a %true return.
+ * While @rwork is guaranteed to be executed after a %false return, the
+ * execution may happen before a full RCU grace period has passed.
+ */
+bool queue_rcu_work_lazy(struct workqueue_struct *wq, struct rcu_work *rwork)
+{
+ struct work_struct *work = &rwork->work;
+
+ if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) {
+ rwork->wq = wq;
+ call_rcu_lazy(&rwork->rcu, rcu_work_rcufn);
+ return true;
+ }
+
+ return false;
+}
+EXPORT_SYMBOL(queue_rcu_work_lazy);
+
+
/**
* worker_enter_idle - enter idle state
* @worker: worker which is entering idle state
--
2.36.0.550.gb090851708-goog
