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Date:   Thu, 3 Jan 2019 15:40:29 -0800
From:   Andi Kleen <ak@linux.intel.com>
To:     Nadav Amit <nadav.amit@gmail.com>
Cc:     Ingo Molnar <mingo@redhat.com>, Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        Edward Cree <ecree@solarflare.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        LKML <linux-kernel@vger.kernel.org>, X86 ML <x86@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Borislav Petkov <bp@alien8.de>,
        David Woodhouse <dwmw@amazon.co.uk>
Subject: Re: [RFC v2 1/6] x86: introduce kernel restartable sequence
Message-ID: <20190103234029.GH6118@tassilo.jf.intel.com>
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> Thanks for the explanations. I don’t think it would work (e.g., IRQs). I can
> avoid generalizing and just detect the "magic sequence” of the code, but let
> me give it some more thought.

If you ask me I would just use compiler profile feedback or autofdo (if your
compiler has a working version)

The compiler can do a much better job at optimizing this than you ever could.

Manual FDO needs some kernel patching though.

-Andi