mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Zhen Lei <thunder.leizhen@huawei.com>
To: "Paul E . McKenney" <paulmck@kernel.org>,
	Frederic Weisbecker <frederic@kernel.org>,
	Neeraj Upadhyay <quic_neeraju@quicinc.com>,
	Joel Fernandes <joel@joelfernandes.org>,
	Josh Triplett <josh@joshtriplett.org>,
	Boqun Feng <boqun.feng@gmail.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
	Lai Jiangshan <jiangshanlai@gmail.com>,
	Zqiang <qiang.zhang1211@gmail.com>, <rcu@vger.kernel.org>,
	<linux-kernel@vger.kernel.org>
Cc: Zhen Lei <thunder.leizhen@huawei.com>
Subject: [PATCH 1/2] rcu: Delete a redundant check in rcu_check_gp_kthread_starvation()
Date: Wed, 5 Jul 2023 15:30:19 +0800	[thread overview]
Message-ID: <20230705073020.2030-2-thunder.leizhen@huawei.com> (raw)
In-Reply-To: <20230705073020.2030-1-thunder.leizhen@huawei.com>

The above condition "if (gpk)" already ensures that gp_kthread is created,
so the local variable 'cpu' cannot be negative here.

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
---
 kernel/rcu/tree_stall.h | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/kernel/rcu/tree_stall.h b/kernel/rcu/tree_stall.h
index b10b8349bb2a48b..dcfaa3d5db2cbc7 100644
--- a/kernel/rcu/tree_stall.h
+++ b/kernel/rcu/tree_stall.h
@@ -537,13 +537,11 @@ static void rcu_check_gp_kthread_starvation(void)
 			pr_err("\tUnless %s kthread gets sufficient CPU time, OOM is now expected behavior.\n", rcu_state.name);
 			pr_err("RCU grace-period kthread stack dump:\n");
 			sched_show_task(gpk);
-			if (cpu >= 0) {
-				if (cpu_is_offline(cpu)) {
-					pr_err("RCU GP kthread last ran on offline CPU %d.\n", cpu);
-				} else  {
-					pr_err("Stack dump where RCU GP kthread last ran:\n");
-					dump_cpu_task(cpu);
-				}
+			if (cpu_is_offline(cpu)) {
+				pr_err("RCU GP kthread last ran on offline CPU %d.\n", cpu);
+			} else  {
+				pr_err("Stack dump where RCU GP kthread last ran:\n");
+				dump_cpu_task(cpu);
 			}
 			wake_up_process(gpk);
 		}
-- 
2.25.1


  reply	other threads:[~2023-07-05  7:31 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-07-05  7:30 [PATCH 0/2] rcu: Don't dump the stalled CPU on where RCU GP kthread last ran twice Zhen Lei
2023-07-05  7:30 ` Zhen Lei [this message]
2023-07-10 19:03   ` [PATCH 1/2] rcu: Delete a redundant check in rcu_check_gp_kthread_starvation() Paul E. McKenney
2023-07-11  3:20     ` Leizhen (ThunderTown)
2023-07-11 16:48       ` Paul E. McKenney
2023-07-13  2:03         ` Leizhen (ThunderTown)
2023-07-05  7:30 ` [PATCH 2/2] rcu: Don't dump the stalled CPU on where RCU GP kthread last ran twice Zhen Lei
2023-07-05  8:17   ` Leizhen (ThunderTown)
2023-07-10 19:05   ` Paul E. McKenney
2023-07-10 19:55     ` Joel Fernandes
2023-07-10 20:32       ` Paul E. McKenney
2023-07-11  3:26         ` Leizhen (ThunderTown)

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=20230705073020.2030-2-thunder.leizhen@huawei.com \
    --to=thunder.leizhen@huawei.com \
    --cc=boqun.feng@gmail.com \
    --cc=frederic@kernel.org \
    --cc=jiangshanlai@gmail.com \
    --cc=joel@joelfernandes.org \
    --cc=josh@joshtriplett.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mathieu.desnoyers@efficios.com \
    --cc=paulmck@kernel.org \
    --cc=qiang.zhang1211@gmail.com \
    --cc=quic_neeraju@quicinc.com \
    --cc=rcu@vger.kernel.org \
    --cc=rostedt@goodmis.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

all inboxes | Powered by JetHome®