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Date:   Tue, 22 Nov 2022 10:16:41 -0300
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Subject: Re: [PATCH] ftrace: Prevent RCU stall on PREEMPT_VOLUNTARY kernels
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To:     rostedt@goodmis.org
Cc:     "Masami Hiramatsu (Google)" <mhiramat@kernel.org>,
        linux-kernel@vger.kernel.org, rcu@vger.kernel.org,
        kernel-dev@igalia.com, kernel@gpiccoli.net,
        "Paul E . McKenney" <paulmck@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>
References: <20221115204847.593616-1-gpiccoli@igalia.com>
 <20221116153620.353819e9c6acb1bf39adeca2@kernel.org>
From:   "Guilherme G. Piccoli" <gpiccoli@igalia.com>
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On 16/11/2022 03:36, Masami Hiramatsu (Google) wrote:
> On Tue, 15 Nov 2022 17:48:47 -0300
> "Guilherme G. Piccoli" <gpiccoli@igalia.com> wrote:
> 
>> The function match_records() may take a while due to a large
>> number of string comparisons, so when in PREEMPT_VOLUNTARY
>> kernels we could face RCU stalls due to that.
>>
>> Add a cond_resched() to prevent that.
>>
>> Suggested-by: Steven Rostedt <rostedt@goodmis.org>
>> Acked-by: Paul E. McKenney <paulmck@kernel.org> # from RCU CPU stall warning perspective
>> Cc: Masami Hiramatsu <mhiramat@kernel.org>
>> Cc: Mark Rutland <mark.rutland@arm.com>
>> Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
> 
> This looks good to me.
> 
> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> 
> Thanks!
> 

Hi Steve, apologies for the ping, just want to ask you if you plan to
take this one or should I change something? Thanks in advance,


Guilherme