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=-11.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED,USER_AGENT_GIT 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 444C6C433E2 for ; Tue, 30 Mar 2021 08:33:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F3AD261999 for ; Tue, 30 Mar 2021 08:33:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231460AbhC3Icg (ORCPT ); Tue, 30 Mar 2021 04:32:36 -0400 Received: from mailgw01.mediatek.com ([210.61.82.183]:54633 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S231330AbhC3IcY (ORCPT ); Tue, 30 Mar 2021 04:32:24 -0400 X-UUID: 159807769e2143cc819d2f8001608f85-20210330 X-UUID: 159807769e2143cc819d2f8001608f85-20210330 Received: from mtkmbs10n1.mediatek.inc [(172.21.101.34)] by mailgw01.mediatek.com (envelope-from ) (Cellopoint E-mail Firewall v4.1.14 Build 0819 with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 615337140; Tue, 30 Mar 2021 16:32:19 +0800 Received: from mtkcas07.mediatek.inc (172.21.101.84) by mtkmbs05n2.mediatek.inc (172.21.101.140) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Tue, 30 Mar 2021 16:32:18 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkcas07.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Tue, 30 Mar 2021 16:32:17 +0800 From: Lecopzer Chen To: CC: , , , , , , , , , , , Subject: Re: [PATCH v5] arm64: Enable perf events based hard lockup detector Date: Tue, 30 Mar 2021 16:32:18 +0800 Message-ID: <20210330083218.22285-1-lecopzer.chen@mediatek.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20210330080615.21938-1-lecopzer.chen@mediatek.com> References: <20210330080615.21938-1-lecopzer.chen@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > Hi Will, Mark, > > > > On Fri, 15 Jan 2021 at 17:32, Sumit Garg wrote: > > > > > > With the recent feature added to enable perf events to use pseudo NMIs > > > as interrupts on platforms which support GICv3 or later, its now been > > > possible to enable hard lockup detector (or NMI watchdog) on arm64 > > > platforms. So enable corresponding support. > > > > > > One thing to note here is that normally lockup detector is initialized > > > just after the early initcalls but PMU on arm64 comes up much later as > > > device_initcall(). So we need to re-initialize lockup detection once > > > PMU has been initialized. > > > > > > Signed-off-by: Sumit Garg > > > --- > > > > > > Changes in v5: > > > - Fix lockup_detector_init() invocation to be rather invoked from CPU > > > binded context as it makes heavy use of per-cpu variables and shouldn't > > > be invoked from preemptible context. > > > > > > > Do you have any further comments on this? > > > > Lecopzer, > > > > Does this feature work fine for you now? > > This really fixes the warning, I have a real hardware for testing this now. > but do we need to call lockup_detector_init() for each cpu? > > In init/main.c, it's only called by cpu 0 for once. Oh sorry, I just misread the code, please ignore previous mail. BRs, Lecopzer