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Message-ID: <e531081f-4871-5292-6a31-782fa7228788@quicinc.com>
Date:   Wed, 25 May 2022 10:29:23 +0530
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Subject: Re: [PATCH] rcu: Add rnp->expmask output to show_rcu_gp_kthreads()
Content-Language: en-US
To:     Zqiang <qiang1.zhang@intel.com>, <paulmck@kernel.org>,
        <frederic@kernel.org>
CC:     <rcu@vger.kernel.org>, <linux-kernel@vger.kernel.org>
References: <20220525044503.2083630-1-qiang1.zhang@intel.com>
From:   Mukesh Ojha <quic_mojha@quicinc.com>
In-Reply-To: <20220525044503.2083630-1-qiang1.zhang@intel.com>
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On 5/25/2022 10:15 AM, Zqiang wrote:
> Currently, for expedited rcu we only check 'rnp->exp_tasks', however
> the 'rnp->exp_tasks' are not always exist for expedited grace period
> that not end. this commit add 'rnp->expmask' condition.
> 
> Signed-off-by: Zqiang <qiang1.zhang@intel.com>

Thanks !! for the patch.
Commit log could require wordsmith from Paul :-)

Reviewed-by: quic_mojha@quicinc.com

-Mukesh

> ---
>   kernel/rcu/tree_stall.h | 6 ++++--
>   1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/kernel/rcu/tree_stall.h b/kernel/rcu/tree_stall.h
> index 2464b0eccfd0..5c4df855f2ac 100644
> --- a/kernel/rcu/tree_stall.h
> +++ b/kernel/rcu/tree_stall.h
> @@ -865,13 +865,15 @@ void show_rcu_gp_kthreads(void)
>   	rcu_for_each_node_breadth_first(rnp) {
>   		if (ULONG_CMP_GE(READ_ONCE(rcu_state.gp_seq), READ_ONCE(rnp->gp_seq_needed)) &&
>   		    !data_race(READ_ONCE(rnp->qsmask)) && !data_race(READ_ONCE(rnp->boost_tasks)) &&
> -		    !data_race(READ_ONCE(rnp->exp_tasks)) && !data_race(READ_ONCE(rnp->gp_tasks)))
> +		    !data_race(READ_ONCE(rnp->expmask)) && !data_race(READ_ONCE(rnp->exp_tasks)) &&
> +			!data_race(READ_ONCE(rnp->gp_tasks)))
>   			continue;
> -		pr_info("\trcu_node %d:%d ->gp_seq %ld ->gp_seq_needed %ld ->qsmask %#lx %c%c%c%c ->n_boosts %ld\n",
> +		pr_info("\trcu_node %d:%d ->gp_seq %ld ->gp_seq_needed %ld ->qsmask %#lx ->expmask %#lx %c%c%c%c ->n_boosts %ld\n",
>   			rnp->grplo, rnp->grphi,
>   			(long)data_race(READ_ONCE(rnp->gp_seq)),
>   			(long)data_race(READ_ONCE(rnp->gp_seq_needed)),
>   			data_race(READ_ONCE(rnp->qsmask)),
> +			data_race(READ_ONCE(rnp->expmask)),
>   			".b"[!!data_race(READ_ONCE(rnp->boost_kthread_task))],
>   			".B"[!!data_race(READ_ONCE(rnp->boost_tasks))],
>   			".E"[!!data_race(READ_ONCE(rnp->exp_tasks))],