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Date:   Mon, 6 Jan 2020 05:11:25 +0100
From:   Frederic Weisbecker <frederic@kernel.org>
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     LKML <linux-kernel@vger.kernel.org>, x86@kernel.org,
        Peter Zijlstra <peterz@infradead.org>,
        Andy Lutomirski <luto@kernel.org>,
        Will Deacon <will@kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>, kvm@vger.kernel.org,
        linux-arch@vger.kernel.org, Mike Rapoport <rppt@linux.ibm.com>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        Miroslav Benes <mbenes@suse.cz>
Subject: Re: [patch V2 09/17] x86/entry: Remove _TIF_NOHZ from
 _TIF_WORK_SYSCALL_ENTRY
Message-ID: <20200106041124.GA26097@lenoir>
References: <20191023122705.198339581@linutronix.de>
 <20191023123118.491328859@linutronix.de>
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On Wed, Oct 23, 2019 at 02:27:14PM +0200, Thomas Gleixner wrote:
> From: Thomas Gleixner <tglx@linutronix.de>
> 
> Evaluating _TIF_NOHZ to decide whether to use the slow syscall entry path
> is not only pointless, it's actually counterproductive:
> 
>  1) Context tracking code is invoked unconditionally before that flag is
>     evaluated.
> 
>  2) If the flag is set the slow path is invoked for nothing due to #1
> 
> Remove it.
> 
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

I'm borrowing this patch for a series of mine. But if you apply
it in the meantime, that would be even better :-)

Thanks!