public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Petr Mladek <pmladek@suse.com>
To: Tejun Heo <tj@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>,
	Michal Koutny <mkoutny@suse.com>,
	linux-kernel@vger.kernel.org, Petr Mladek <pmladek@suse.com>
Subject: [PATCH v2 3/5] workqueue: Interrupted create_worker() is not a repeated event
Date: Tue,  7 Mar 2023 13:53:33 +0100	[thread overview]
Message-ID: <20230307125335.28805-4-pmladek@suse.com> (raw)
In-Reply-To: <20230307125335.28805-1-pmladek@suse.com>

kthread_create_on_node() might get interrupted(). It is rare but realistic.
For example, when an unbound workqueue is allocated in module_init()
callback. It is done in the context of the "modprobe" process. And,
for example, systemd might kill pending processes when switching root
from initrd to the booted system.

The interrupt is a one-off event and the race might be hard to reproduce.
It is always worth printing.

Signed-off-by: Petr Mladek <pmladek@suse.com>
---
 kernel/workqueue.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 36ad9a4d65e4..16439d79d164 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -1961,8 +1961,13 @@ static struct worker *create_worker(struct worker_pool *pool)
 	worker->task = kthread_create_on_node(worker_thread, worker, pool->node,
 					      "kworker/%s", id_buf);
 	if (IS_ERR(worker->task)) {
-		pr_err_once("workqueue: Failed to create a worker thread: %pe",
-			    worker->task);
+		if (PTR_ERR(worker->task) == -EINTR) {
+			pr_err("workqueue: Interrupted when creating a worker thread \"kworker/%s\"\n",
+			       id_buf);
+		} else {
+			pr_err_once("workqueue: Failed to create a worker thread: %pe",
+				    worker->task);
+		}
 		goto fail;
 	}
 
-- 
2.35.3


  parent reply	other threads:[~2023-03-07 12:54 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-07 12:53 [PATCH v2 0/5] workqueue: Debugging improvements Petr Mladek
2023-03-07 12:53 ` [PATCH v2 1/5] workqueue: Fix hung time report of worker pools Petr Mladek
2023-03-07 12:53 ` [PATCH v2 2/5] workqueue: Warn when a new worker could not be created Petr Mladek
2023-03-07 12:53 ` Petr Mladek [this message]
2023-03-07 12:53 ` [PATCH v2 4/5] workqueue: Warn when a rescuer " Petr Mladek
2023-03-07 12:53 ` [PATCH v2 5/5] workqueue: Print backtraces from CPUs with hung CPU bound workqueues Petr Mladek
2023-03-17 22:04 ` [PATCH v2 0/5] workqueue: Debugging improvements Tejun Heo

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20230307125335.28805-4-pmladek@suse.com \
    --to=pmladek@suse.com \
    --cc=jiangshanlai@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mkoutny@suse.com \
    --cc=tj@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox