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Date:   Mon, 10 Jul 2023 13:32:59 -0700
From:   "Paul E. McKenney" <paulmck@kernel.org>
To:     Joel Fernandes <joel@joelfernandes.org>
Cc:     Zhen Lei <thunder.leizhen@huawei.com>,
        Frederic Weisbecker <frederic@kernel.org>,
        Neeraj Upadhyay <quic_neeraju@quicinc.com>,
        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
Subject: Re: [PATCH 2/2] rcu: Don't dump the stalled CPU on where RCU GP
 kthread last ran twice
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 <CAEXW_YR_t-x-eYKLFmruOLqZv91oi=AJKEEeuqYosejjdscn1g@mail.gmail.com>
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On Mon, Jul 10, 2023 at 03:55:16PM -0400, Joel Fernandes wrote:
> On Mon, Jul 10, 2023 at 3:06 PM Paul E. McKenney <paulmck@kernel.org> wrote:
> >
> > On Wed, Jul 05, 2023 at 03:30:20PM +0800, Zhen Lei wrote:
> > > The stacks of all stalled CPUs will be dumped. If the CPU on where RCU GP
> > > kthread last ran is stalled, its stack does not need to be dumped again.
> > >
> > > Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
> >
> > This one looks good.  Please feel free to rebase it before 1/2 and repost.
> 
> Just a small comment:
> I wondered if this would make it harder to identify which stack among
> the various CPU stacks corresponds to the one the GP kthread is
> running on. However, this line does print the CPU number of the
> thread, so it is perhaps not an issue:
> 
>                 pr_err("%s kthread starved for %ld jiffies! g%ld f%#x
> %s(%d) ->state=%#x ->cpu=%d\n",
> 
> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>

Thank you!  Zhen Lei, please feel free to add Joel's Reviewed-by on your
next posting.

							Thanx, Paul