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From:   Thomas Gleixner <tglx@linutronix.de>
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To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     "Paul E. McKenney" <paulmck@kernel.org>,
        linux-kernel@vger.kernel.org,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Karol Herbst <karolherbst@gmail.com>,
        Pekka Paalanen <ppaalanen@gmail.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@kernel.org>, Borislav Petkov <bp@alien8.de>
Subject: Re: [for-next][PATCH 13/25] x86/mm/kmmio: Use
 rcu_read_lock_sched_notrace()
In-Reply-To: <20221210185555.7abc4de4@gandalf.local.home>
References: <20221210135750.425719934@goodmis.org>
 <20221210135825.241167123@goodmis.org>
 <20221210174753.GD4001@paulmck-ThinkPad-P17-Gen-1>
 <20221210133425.4657985e@gandalf.local.home> <87359mdeg3.ffs@tglx>
 <20221210185555.7abc4de4@gandalf.local.home>
Date:   Mon, 12 Dec 2022 11:51:51 +0100
Message-ID: <87wn6wc2t4.ffs@tglx>
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On Sat, Dec 10 2022 at 18:55, Steven Rostedt wrote:
> On Sun, 11 Dec 2022 00:30:36 +0100
> Thomas Gleixner <tglx@linutronix.de> wrote:
>> I concede that there are hot paths which actually can benefit, but this
>> code has exactly _ZERO_ benefit from that. Taking that tracing exception
>> and handling it is orders of magnitudes more expensive than a regular
>> preempt_enable().
>> 
>> So just get rid of it and don't proliferate cargo cult programming.
>> 
> The point of the patch is to just fix the lockdep issue. I'm happy to
> remove that "no_resched" (I was planning to), but that would be a separate
> change, with a different purpose, and thus a separate patch.

Right, but please make that part of the series.

Thanks,

        tglx