Re: [PATCH v2 1/2] x86/msr: Carry on after a non-"safe" MSR access fails without !panic_on_oops

From: Linus Torvalds
Date: Mon Sep 21 2015 - 12:36:21 EST


On Mon, Sep 21, 2015 at 1:46 AM, Ingo Molnar <mingo@xxxxxxxxxx> wrote:
>
> Linus, what's your preference?

So quite frankly, is there any reason we don't just implement
native_read_msr() as just

unsigned long long native_read_msr(unsigned int msr)
{
int err;
unsigned long long val;

val = native_read_msr_safe(msr, &err);
WARN_ON_ONCE(err);
return val;
}

Note: no inline, no nothing. Just put it in arch/x86/lib/msr.c, and be
done with it. I don't see the downside.

How many msr reads are <i>so</i> critical that the function call
overhead would matter? Get rid of the inline version of the _safe()
thing too, and put that thing there too.

Linus
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