From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 16025C2BB1D for ; Tue, 14 Apr 2020 21:42:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DAAA720768 for ; Tue, 14 Apr 2020 21:42:49 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="GLXZ6cso" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2634038AbgDNVmo (ORCPT ); Tue, 14 Apr 2020 17:42:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51790 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S2633992AbgDNVlC (ORCPT ); Tue, 14 Apr 2020 17:41:02 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7A98DC061A0F; Tue, 14 Apr 2020 14:41:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=6fW3z+0t6iwTFLSm5U6E4jEaZgRMxQt5XSHRbl0FIRU=; b=GLXZ6cso7/Kc9otHNvl8xNFk/k 3UnSjYeKFsTUOkbVxZK/gCzgj1My1hl1o3jN3fQjv1wk+Wcz3SnclnAqLfm/yckHoXM7vds9UZWPk HiZCwOWAXCGu8TV0dcePkHD5azQHaMnHr6dltqVKK1OESvty+X5Zwsy+1hg+KF9s7e5rRTJNd4stR xTkUdigirsUtpJxm86+4YWDYH6VbuvVVqnjwGKKd3UI3rC3yG4o+c77Yq0+n46YXKePWcmCaf5IzP fVUyWu0XWZWK4NiaUttgeKRC2lNfWOK5+c1qSqDnVzPX1/Na7uCSAF0p8QPY6a5B1GiPXQCNwLED9 2svhZsBQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=worktop.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jOTIY-00026w-Rw; Tue, 14 Apr 2020 21:40:51 +0000 Received: by worktop.programming.kicks-ass.net (Postfix, from userid 1000) id 8BF8F981086; Tue, 14 Apr 2020 23:40:48 +0200 (CEST) Date: Tue, 14 Apr 2020 23:40:48 +0200 From: Peter Zijlstra To: "Jason A. Donenfeld" Cc: linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, x86@kernel.org, arnd@arndb.de, srinivas.pandruvada@linux.intel.com, bberg@redhat.com, bp@suse.de, "Rafael J. Wysocki" Subject: Re: [PATCH 3/3] x86/mce/therm_throt: allow disabling the thermal vector altogether Message-ID: <20200414214048.GL2483@worktop.programming.kicks-ass.net> References: <20200407063345.4484-1-Jason@zx2c4.com> <20200407063345.4484-3-Jason@zx2c4.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200407063345.4484-3-Jason@zx2c4.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-edac-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-edac@vger.kernel.org On Tue, Apr 07, 2020 at 12:33:45AM -0600, Jason A. Donenfeld wrote: > The thermal IRQ handler uses 1.21% CPU on my system when it's hot from > compiling things. Indeed looking at /proc/interrupts reveals quite a lot > of events coming in. Beyond logging them, the existing drivers on the > system don't appear to do very much that I'm interested in. So, add a > way to disable this entirely so that I can regain precious CPU cycles. Why is this MCE code?!? hysterical raisins? Anyway, I wonder if this is something we should hook up to SCHED_THERMAL_PRESSURE, Rafael? > diff --git a/arch/x86/kernel/cpu/mce/intel.c b/arch/x86/kernel/cpu/mce/intel.c > index f996ffb887bc..d14f1922fb49 100644 > --- a/arch/x86/kernel/cpu/mce/intel.c > +++ b/arch/x86/kernel/cpu/mce/intel.c > @@ -511,7 +511,8 @@ static void intel_ppin_init(struct cpuinfo_x86 *c) > > void mce_intel_feature_init(struct cpuinfo_x86 *c) > { > - intel_init_thermal(c); > + if (IS_ENABLED(CONFIG_X86_THERMAL_VECTOR)) > + intel_init_thermal(c); > intel_init_cmci(); > intel_init_lmce(); > intel_ppin_init(c); > -- > 2.26.0 >