From: Tejun Heo <tj@kernel.org>
To: axboe@kernel.dk, laijs@cn.fujitsu.com, fengguang.wu@intel.com
Cc: linux-kernel@vger.kernel.org, jmoyer@redhat.com,
Tejun Heo <tj@kernel.org>
Subject: [PATCH 1/4] implement current_is_workqueue_rescuer()
Date: Thu, 7 Mar 2013 13:44:06 -0800 [thread overview]
Message-ID: <1362692649-25570-2-git-send-email-tj@kernel.org> (raw)
In-Reply-To: <1362692649-25570-1-git-send-email-tj@kernel.org>
Implement a function which queries whether it currently is running off
a workqueue rescuer. This will be used to convert writeback to
workqueue.
Signed-off-by: Tejun Heo <tj@kernel.org>
---
include/linux/workqueue.h | 1 +
kernel/workqueue.c | 13 +++++++++++++
2 files changed, 14 insertions(+)
diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
index 7f6d29a..df30763 100644
--- a/include/linux/workqueue.h
+++ b/include/linux/workqueue.h
@@ -451,6 +451,7 @@ extern bool cancel_delayed_work_sync(struct delayed_work *dwork);
extern void workqueue_set_max_active(struct workqueue_struct *wq,
int max_active);
+extern bool current_is_workqueue_rescuer(void);
extern bool workqueue_congested(int cpu, struct workqueue_struct *wq);
extern unsigned int work_busy(struct work_struct *work);
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 904a901..af79dd8 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -4062,6 +4062,19 @@ void workqueue_set_max_active(struct workqueue_struct *wq, int max_active)
EXPORT_SYMBOL_GPL(workqueue_set_max_active);
/**
+ * current_is_workqueue_rescuer - is %current workqueue rescuer?
+ *
+ * Determine whether %current is a workqueue rescuer. Can be used from
+ * work functions to determine whether it's being run off the rescuer task.
+ */
+bool current_is_workqueue_rescuer(void)
+{
+ struct worker *worker = current_wq_worker();
+
+ return worker && worker == worker->current_pwq->wq->rescuer;
+}
+
+/**
* workqueue_congested - test whether a workqueue is congested
* @cpu: CPU in question
* @wq: target workqueue
--
1.8.1.4
next prev parent reply other threads:[~2013-03-07 21:44 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-03-07 21:44 [PATCHSET] writeback: convert writeback to unbound workqueue Tejun Heo
2013-03-07 21:44 ` Tejun Heo [this message]
2013-03-13 0:42 ` [PATCH 1/4] implement current_is_workqueue_rescuer() Tejun Heo
2013-03-07 21:44 ` [PATCH 2/4] writeback: remove unused bdi_pending_list Tejun Heo
2013-03-12 12:02 ` Jan Kara
2013-03-07 21:44 ` [PATCH 3/4] writeback: replace custom worker pool implementation with unbound workqueue Tejun Heo
2013-03-12 15:05 ` Jan Kara
2013-03-18 22:32 ` Jan Kara
2013-03-18 22:35 ` Tejun Heo
2013-03-19 15:46 ` Jan Kara
2013-03-19 17:28 ` Tejun Heo
2013-03-21 1:57 ` Dave Chinner
2013-03-21 5:07 ` Tejun Heo
2013-03-21 11:32 ` Jan Kara
2013-03-21 13:08 ` Christoph Hellwig
2013-03-21 18:37 ` Tejun Heo
2013-03-07 21:44 ` [PATCH 4/4] writeback: expose the bdi_wq workqueue Tejun Heo
2013-03-12 15:06 ` [PATCHSET] writeback: convert writeback to unbound workqueue Jens Axboe
2013-03-12 17:10 ` Tejun Heo
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