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Date:   Thu, 8 Nov 2018 12:18:23 +0100 (CET)
From:   Thomas Gleixner <tglx@linutronix.de>
To:     Tim Chen <tim.c.chen@linux.intel.com>
cc:     Jiri Kosina <jikos@kernel.org>,
        Tom Lendacky <thomas.lendacky@amd.com>,
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Subject: Re: [Patch v4 07/18] x86/smt: Convert cpu_smt_control check to
 cpu_smt_enabled static key
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Tim,

On Wed, 7 Nov 2018, Tim Chen wrote:
> On 11/03/2018 11:29 AM, Thomas Gleixner wrote:
> > Tim,
> > 
> > On Tue, 30 Oct 2018, Tim Chen wrote:
> > 
> >> Change the SMT code paths check from using cpu_smt_control to
> >> cpu_smt_enabled static key.  This saves a branching check.
> > 
> > and adds extra size to the kernel for the patching. The only reason why it
> > would make sense for kvm is that then the EXPORT of cpu_smt_control can go
> > away, which takes more space than the patch data.
> > 
> 
> Should I just drop this patch then and only replace
> sched_smt_present with cpu_smt_enabled?

You have to decide which of the exports to drop. No strong opinion.

Thanks,

	tglx