Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754840AbcCNFZK (ORCPT ); Mon, 14 Mar 2016 01:25:10 -0400 Received: from mail-ob0-f173.google.com ([209.85.214.173]:35393 "EHLO mail-ob0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754813AbcCNFZI (ORCPT ); Mon, 14 Mar 2016 01:25:08 -0400 MIME-Version: 1.0 In-Reply-To: <1A7043D5F58CCB44A599DFD55ED4C94846A12FBC@fmsmsx115.amr.corp.intel.com> References: <1A7043D5F58CCB44A599DFD55ED4C94846A12FBC@fmsmsx115.amr.corp.intel.com> From: Andy Lutomirski Date: Sun, 13 Mar 2016 22:24:47 -0700 Message-ID: Subject: Re: C1E auto-promotion suspend/resume To: "Brown, Len" Cc: "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2251 Lines: 50 On Sun, Mar 13, 2016 at 9:31 PM, Brown, Len wrote: >> By BIOS (1.2.3 on a Dell XPS 13 9350) seems to want to enable C1E >> auto-promotion (ugh!), which results in this difference across >> suspend/resume according to turbostat: >> >> -cpu3: MSR_IA32_POWER_CTL: 0x0024005d (C1E auto-promotion: DISabled) >> +cpu3: MSR_IA32_POWER_CTL: 0x0024005f (C1E auto-promotion: ENabled) >> >> Should intel_idle learn to re-disable idle promotion on resume? > > Yes, it seems that way. > > Go ahead and send a patch, or file a bug at bugzilla.kernel.org > and we'll get to it. Sent. The only other differences I see across suspend/resume in turbostat --debug (with taskset -c 0 to suppress spurious junk) are: --- pre-susp.txt 2016-03-13 22:21:39.889337697 -0700 +++ post-susp.txt 2016-03-13 21:38:20.782503438 -0700 @@ -24,8 +24,8 @@ cpu0: MSR_NHM_SNB_PKG_CST_CFG_CTL: 0x1e008006 (UNdemote-C3, UNdemote-C1, demote-C3, demote-C1, locked: pkg-cstate-limit=6: pc8) cpu0: MSR_PM_ENABLE: 0x00000001 (HWP) cpu0: MSR_HWP_CAPABILITIES: 0x0108171c (high 0x1c guar 0x17 eff 0x8 low 0x1) -cpu0: MSR_HWP_REQUEST: 0x80001c04 (min 0x4 max 0x1c des 0x0 epp 0x80 window 0x0 pkg 0x0) -cpu0: MSR_HWP_INTERRUPT: 0x00000001 (EN_Guaranteed_Perf_Change, Dis_Excursion_Min) +cpu0: MSR_HWP_REQUEST: 0x8000ff01 (min 0x1 max 0xff des 0x0 epp 0x80 window 0x0 pkg 0x0) +cpu0: MSR_HWP_INTERRUPT: 0x00000000 (Dis_Guaranteed_Perf_Change, Dis_Excursion_Min) cpu0: MSR_HWP_STATUS: 0x00000000 (No-Guaranteed_Perf_Change, No-Excursion_Min) cpu0: MSR_IA32_ENERGY_PERF_BIAS: 0x00000006 (balanced) cpu0: MSR_RAPL_POWER_UNIT: 0x000a0e03 (0.125000 Watts, 0.000061 Joules, 0.000977 sec.) @@ -36,6 +36,6 @@ cpu0: MSR_DRAM_POWER_LIMIT: 0x5400de00000000 (UNlocked) cpu0: DRAM Limit: DISabled (0.000000 Watts, 0.000977 sec, clamp DISabled) cpu0: MSR_IA32_TEMPERATURE_TARGET: 0x00640000 (100 C) -cpu0: MSR_IA32_PACKAGE_THERM_STATUS: 0x88360000 (46 C) -cpu0: MSR_IA32_THERM_STATUS: 0x88360000 (46 C +/- 1) -cpu1: MSR_IA32_THERM_STATUS: 0x88360000 (46 C +/- 1) +cpu0: MSR_IA32_PACKAGE_THERM_STATUS: 0x883c0000 (40 C) +cpu0: MSR_IA32_THERM_STATUS: 0x883c0000 (40 C +/- 1) +cpu1: MSR_IA32_THERM_STATUS: 0x88400000 (36 C +/- 1) Are either of those potentially interesting?