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Subject: Re: [PATCH v2 1/2] x86, msr: add rdmsr_safe_on_cpu_resched() and use
 it in msr_read()
To:     Thomas Gleixner <tglx@linutronix.de>,
        Eric Dumazet <edumazet@google.com>
Cc:     x86 <x86@kernel.org>, lkml <linux-kernel@vger.kernel.org>,
        "H. Peter Anvin" <hpa@zytor.com>, Ingo Molnar <mingo@redhat.com>,
        Hugh Dickins <hughd@google.com>, Borislav Petkov <bp@alien8.de>
References: <20180319152503.123372-1-edumazet@google.com>
 <alpine.DEB.2.21.1803232221550.1481@nanos.tec.linutronix.de>
From:   Eric Dumazet <eric.dumazet@gmail.com>
Message-ID: <f4e89d95-1cd8-a9c9-cc93-77c35d82e76b@gmail.com>
Date:   Fri, 23 Mar 2018 14:30:58 -0700
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On 03/23/2018 02:27 PM, Thomas Gleixner wrote:
>
> Looking at all call sites. None of them is performance critical and all of
> them are in preemptible context.
> 
> So we simply can switch the rdmsr_safe_on_cpu() implementation over to wait
> mode completely.

SGTM, thanks for looking, I will send a v3 then.

> 
>> +/* Note: This version spins in smp_call_function_single().
>> + * Consider using rdmsr_safe_on_cpu_resched() variant instead.
> 
> Bah. This is not networking code. x86 uses sensible comment style :)

Right ;)