From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH v2 1/2] x86/msr: Carry on after a non-"safe" MSR access
 fails without !panic_on_oops
Date: Wed, 30 Sep 2015 11:32:00 -0700
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Cc: Andy Lutomirski <luto@amacapital.net>,
	Thomas Gleixner <tglx@linutronix.de>,
	Paolo Bonzini <pbonzini@redhat.com>,
	xen-devel <Xen-devel@lists.xen.org>,
	Arjan van de Ven <arjan@linux.intel.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	KVM list <kvm@vger.kernel.org>,
	the arch/x86 maintainers <x86@kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Peter Zijlstra <peterz@infradead.org>
To: Linus Torvalds <torvalds@linux-foundation.org>,
	Ingo Molnar <mingo@kernel.org>
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On 09/21/2015 09:36 AM, Linus Torvalds wrote:
> 
> 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.
> 

Probably only the ones that may go in the context switch path.

	-hpa