From mboxrd@z Thu Jan 1 00:00:00 1970 From: Len Brown Subject: [RESEND 2] [PATCH 0/2] Rewrite power limit notification interrupt handling Date: Tue, 21 May 2013 12:53:12 -0400 Message-ID: <1369155194-9535-1-git-send-email-lenb@kernel.org> References: <1368741246-3998-1-git-send-email-lenb@kernel.org> Return-path: Received: from mail-qe0-f43.google.com ([209.85.128.43]:47943 "EHLO mail-qe0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751282Ab3EUQxk (ORCPT ); Tue, 21 May 2013 12:53:40 -0400 Received: by mail-qe0-f43.google.com with SMTP id k5so528089qej.30 for ; Tue, 21 May 2013 09:53:39 -0700 (PDT) In-Reply-To: <1368741246-3998-1-git-send-email-lenb@kernel.org> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: rui.zhang@intel.com Cc: linux-pm@vger.kernel.org [Excluse duplicates -- for some reason these didn't hit list archives or patchwork] The "Power Limit Notification" (X86_FEATURE_PLN) was added in Sandy Bridge to give the OS the option of knowing when the package has reached a configured power threshold. Linux-2.6.36 enabled this feature: 0199114c31798af5b83841b21759b64171060d9b (x86, hwmon: Package Level Thermal/Power: power limit) It enabld the interrupt, and the interrupt hander added to the MCE log and printed to the console: printk(KERN_CRIT "CPU%d: %s power limit notification (total events = %lu) printk(KERN_INFO "CPU%d: %s power limit normal\n" However, these events are quite routine on some systems under some conditions, alarming customers and provoking un-necessary customer support calls. So the MCE log entry was deleted in Linux-3.3: 29e9bf1841e4f9df13b4992a716fece7087dd237 (x86, mce, therm_throt: Don't report power limit and package level thermal throttle events in mcelog) Here we delete the corresponding kernel console messages, and then we disable the interrupt by default -- allowing it to be enabled by cmdline for diagnosis purposes. https://bugzilla.kernel.org/show_bug.cgi?id=36182 This pair of patches applies cleanly back to Linux-3.3. Documentation/kernel-parameters.txt | 2 ++ arch/x86/kernel/cpu/mcheck/therm_throt.c | 43 ++++++++++++++++++++++++++----------------- 2 files changed, 28 insertions(+), 17 deletions(-) This pair of patches applies cleanly back to Linux-3.3. Fenghua Yu (2): [1/2] x86 thermal: Delete power-limit-notification console messages [2/2] x86 thermal: Disable power limit notification interrupt by default