Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751745AbbFBXi1 (ORCPT ); Tue, 2 Jun 2015 19:38:27 -0400 Received: from mga11.intel.com ([192.55.52.93]:33077 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751360AbbFBXiW (ORCPT ); Tue, 2 Jun 2015 19:38:22 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.13,543,1427785200"; d="scan'208";a="719655796" Date: Tue, 2 Jun 2015 16:38:20 -0700 From: Andi Kleen To: Thomas Gleixner Cc: Andy Lutomirski , Adrian Hunter , LKML , Linus Torvalds , X86 ML , "H. Peter Anvin" , Len Brown Subject: Re: [PATCH RFC] x86, tsc: Allow for high latency in quick_pit_calibrate() Message-ID: <20150602233820.GP1187@tassilo.jf.intel.com> References: <1432194944-29087-1-git-send-email-adrian.hunter@intel.com> <20150602194350.GN1187@tassilo.jf.intel.com> <20150602202037.GO1187@tassilo.jf.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 879 Lines: 24 On Tue, Jun 02, 2015 at 11:03:26PM +0200, Thomas Gleixner wrote: > > > On Tue, 2 Jun 2015, Andi Kleen wrote: > > > > There's the code in tsc_msr.c. It should be relatively > > > straightforward to extend it to cover everything that intel_pstate > > > supports. > > > > That's a good idea, but we still need an always working fallback when the > > model number is not available. So Adrian's patch is needed in any > > case. > > Nonsense. The slow calibration is already a working fallback. Please read Adrian's description again. It's not working when the PIT read is too slow. That is when the new algorithm is needed. -Andi -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/