[PATCH] workqueue: Rename rescuer kworker

[Aaron Tomlin]

Each CPU-specific and unbound kworker kthread conforms to a particular
naming scheme. However, this does not extend to the rescuer kworker.
At present, a rescuer kworker is simply named according to its
workqueue's name. This can be cryptic.

>From the context of user-mode, it can be useful to identify a rescuer
kworker since their CPU affinity cannot be modified and their initial
CPU assignment can be safely ignored. By design a rescuer kworker can
run anywhere and only processes work items in an emergency situation.

This patch modifies a rescuer to follow the kworker naming scheme.
The "r" and "-" is indicative of a rescuer and its workqueue's
name respectively e.g. "kworker/r-ext4-rsv-conver".

Signed-off-by: Aaron Tomlin <atomlin@xxxxxxxxxxx>
---
 kernel/workqueue.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 02a8f402eeb5..d9bb375b8d02 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -4599,7 +4599,7 @@ static int init_rescuer(struct workqueue_struct *wq)
 	}
 
 	rescuer->rescue_wq = wq;
-	rescuer->task = kthread_create(rescuer_thread, rescuer, "%s", wq->name);
+	rescuer->task = kthread_create(rescuer_thread, rescuer, "kworker/r-%s", wq->name);
 	if (IS_ERR(rescuer->task)) {
 		ret = PTR_ERR(rescuer->task);
 		pr_err("workqueue: Failed to create a rescuer kthread for wq \"%s\": %pe",
-- 
2.39.1