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=-0.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by aws-us-west-2-korg-lkml-1.web.codeaurora.org (Postfix) with ESMTP id 34446C433EF for ; Thu, 14 Jun 2018 01:30:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D80CE208D8 for ; Thu, 14 Jun 2018 01:30:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D80CE208D8 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935789AbeFNBaL (ORCPT ); Wed, 13 Jun 2018 21:30:11 -0400 Received: from mga04.intel.com ([192.55.52.120]:35008 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935530AbeFNBaK (ORCPT ); Wed, 13 Jun 2018 21:30:10 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 13 Jun 2018 18:30:09 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,220,1526367600"; d="scan'208";a="66830739" Received: from voyager.sc.intel.com (HELO voyager) ([10.3.52.149]) by orsmga002.jf.intel.com with ESMTP; 13 Jun 2018 18:30:08 -0700 Date: Wed, 13 Jun 2018 18:26:32 -0700 From: Ricardo Neri To: Peter Zijlstra Cc: Nicholas Piggin , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Andi Kleen , Ashok Raj , Borislav Petkov , Tony Luck , "Ravi V. Shankar" , x86@kernel.org, sparclinux@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Jacob Pan , Don Zickus , Michael Ellerman , Frederic Weisbecker , Babu Moger , "David S. Miller" , Benjamin Herrenschmidt , Paul Mackerras , Mathieu Desnoyers , Masami Hiramatsu , Andrew Morton , Philippe Ombredanne , Colin Ian King , "Luis R. Rodriguez" , iommu@lists.linux-foundation.org Subject: Re: [RFC PATCH 12/23] kernel/watchdog: Introduce a struct for NMI watchdog operations Message-ID: <20180614012632.GB22652@voyager> References: <1528851463-21140-1-git-send-email-ricardo.neri-calderon@linux.intel.com> <1528851463-21140-13-git-send-email-ricardo.neri-calderon@linux.intel.com> <20180613174141.539fc6c1@roar.ozlabs.ibm.com> <20180613084219.GT12258@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180613084219.GT12258@hirez.programming.kicks-ass.net> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 13, 2018 at 10:42:19AM +0200, Peter Zijlstra wrote: > On Wed, Jun 13, 2018 at 05:41:41PM +1000, Nicholas Piggin wrote: > > On Tue, 12 Jun 2018 17:57:32 -0700 > > Ricardo Neri wrote: > > > > > Instead of exposing individual functions for the operations of the NMI > > > watchdog, define a common interface that can be used across multiple > > > implementations. > > > > > > The struct nmi_watchdog_ops is defined for such operations. These initial > > > definitions include the enable, disable, start, stop, and cleanup > > > operations. > > > > > > Only a single NMI watchdog can be used in the system. The operations of > > > this NMI watchdog are accessed via the new variable nmi_wd_ops. This > > > variable is set to point the operations of the first NMI watchdog that > > > initializes successfully. Even though at this moment, the only available > > > NMI watchdog is the perf-based hardlockup detector. More implementations > > > can be added in the future. > > > > Cool, this looks pretty nice at a quick glance. sparc and powerpc at > > least have their own NMI watchdogs, it would be good to have those > > converted as well. > > Yeah, agreed, this looks like half a patch. I planned to look into the conversion of sparc and powerpc. I just wanted to see the reception to these patches before jumping and do potentially useless work. Comments in this thread lean towards keep using the weak stubs. Thanks and BR, Ricardo