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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,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 1FB24C43381 for ; Wed, 27 Feb 2019 16:06:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id ED70621850 for ; Wed, 27 Feb 2019 16:06:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730144AbfB0QGD (ORCPT ); Wed, 27 Feb 2019 11:06:03 -0500 Received: from mga02.intel.com ([134.134.136.20]:24160 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730062AbfB0QF7 (ORCPT ); Wed, 27 Feb 2019 11:05:59 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 27 Feb 2019 08:05:58 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.58,420,1544515200"; d="scan'208";a="303011741" Received: from unknown (HELO luv-build.sc.intel.com) ([172.25.110.25]) by orsmga005.jf.intel.com with ESMTP; 27 Feb 2019 08:05:56 -0800 From: Ricardo Neri To: Thomas Gleixner , Ingo Molnar , Borislav Petkov Cc: Ashok Raj , Andi Kleen , Peter Zijlstra , "Ravi V. Shankar" , x86@kernel.org, linux-kernel@vger.kernel.org, Ricardo Neri , Ricardo Neri , "H. Peter Anvin" , Tony Luck , Clemens Ladisch , Arnd Bergmann , Philippe Ombredanne , Kate Stewart , "Rafael J. Wysocki" , Mimi Zohar , Jan Kiszka , Nick Desaulniers , Masahiro Yamada , Nayna Jain Subject: [RFC PATCH v2 14/14] x86/watchdog: Add a shim hardlockup detector Date: Wed, 27 Feb 2019 08:05:18 -0800 Message-Id: <1551283518-18922-15-git-send-email-ricardo.neri-calderon@linux.intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1551283518-18922-1-git-send-email-ricardo.neri-calderon@linux.intel.com> References: <1551283518-18922-1-git-send-email-ricardo.neri-calderon@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The generic hardlockup detector is based on perf. It also provides a set of weak stubs that CPU architectures can override. Add a shim hardlockup detector for x86 that selects between perf and hpet implementations. Specifically, this shim implementation is needed for the HPET-based hardlockup detector; it can also be used for future implementations. Cc: "H. Peter Anvin" Cc: Ashok Raj Cc: Andi Kleen Cc: Tony Luck Cc: Peter Zijlstra Cc: Clemens Ladisch Cc: Arnd Bergmann Cc: Philippe Ombredanne Cc: Kate Stewart Cc: "Rafael J. Wysocki" Cc: Mimi Zohar Cc: Jan Kiszka Cc: Nick Desaulniers Cc: Masahiro Yamada Cc: Nayna Jain Cc: "Ravi V. Shankar" Cc: x86@kernel.org Suggested-by: Nicholas Piggin Signed-off-by: Ricardo Neri --- arch/x86/Kconfig.debug | 4 ++ arch/x86/kernel/Makefile | 1 + arch/x86/kernel/watchdog_hld.c | 78 ++++++++++++++++++++++++++++++++++ 3 files changed, 83 insertions(+) create mode 100644 arch/x86/kernel/watchdog_hld.c diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug index 3a2845a29e8a..5e5f4d2330af 100644 --- a/arch/x86/Kconfig.debug +++ b/arch/x86/Kconfig.debug @@ -169,10 +169,14 @@ config IOMMU_LEAK config HAVE_MMIOTRACE_SUPPORT def_bool y +config X86_HARDLOCKUP_DETECTOR + bool + config X86_HARDLOCKUP_DETECTOR_HPET bool "Use HPET Timer for Hard Lockup Detection" select SOFTLOCKUP_DETECTOR select HARDLOCKUP_DETECTOR + select X86_HARDLOCKUP_DETECTOR depends on HPET_TIMER && HPET && X86_64 help Say y to enable a hardlockup detector that is driven by an High- diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 9d610e8a9224..5372453fe2a7 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -106,6 +106,7 @@ obj-$(CONFIG_VM86) += vm86_32.o obj-$(CONFIG_EARLY_PRINTK) += early_printk.o obj-$(CONFIG_HPET_TIMER) += hpet.o +obj-$(CONFIG_X86_HARDLOCKUP_DETECTOR) += watchdog_hld.o obj-$(CONFIG_X86_HARDLOCKUP_DETECTOR_HPET) += watchdog_hld_hpet.o obj-$(CONFIG_APB_TIMER) += apb_timer.o diff --git a/arch/x86/kernel/watchdog_hld.c b/arch/x86/kernel/watchdog_hld.c new file mode 100644 index 000000000000..a2f6190dbce0 --- /dev/null +++ b/arch/x86/kernel/watchdog_hld.c @@ -0,0 +1,78 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * A shim hardlockup detector. It simply overrides the weak stubs of the + * generic implementation. + * + * Copyright (C) Intel Corporation 2019 + */ + +#include +#include + +enum x86_hardlockup_detector { + X86_HARDLOCKUP_DETECTOR_PERF, + X86_HARDLOCKUP_DETECTOR_HPET, +}; + +static enum __read_mostly x86_hardlockup_detector detector_type; + +int watchdog_nmi_enable(unsigned int cpu) +{ + if (detector_type == X86_HARDLOCKUP_DETECTOR_PERF) { + hardlockup_detector_perf_enable(); + return 0; + } + + if (detector_type == X86_HARDLOCKUP_DETECTOR_HPET) { + hardlockup_detector_hpet_enable(); + return 0; + } + + return -ENODEV; +} + +void watchdog_nmi_disable(unsigned int cpu) +{ + if (detector_type == X86_HARDLOCKUP_DETECTOR_PERF) { + hardlockup_detector_perf_disable(); + return; + } + + if (detector_type == X86_HARDLOCKUP_DETECTOR_HPET) { + hardlockup_detector_hpet_disable(); + return; + } +} + +int __init watchdog_nmi_probe(void) +{ + int ret; + + /* + * Try first with the HPET hardlockup detector. It will only + * succeed if selected at build time and the nmi_watchdog + * command-line parameter is configured. This ensure that the + * perf-based detector is used by default, if selected at + * build time. + */ + ret = hardlockup_detector_hpet_init(); + if (!ret) { + detector_type = X86_HARDLOCKUP_DETECTOR_HPET; + return ret; + } + + ret = hardlockup_detector_perf_init(); + if (!ret) { + detector_type = X86_HARDLOCKUP_DETECTOR_PERF; + return ret; + } + + return ret; +} + +void watchdog_nmi_stop(void) +{ + /* Only the HPET lockup detector defines a stop function. */ + if (detector_type == X86_HARDLOCKUP_DETECTOR_HPET) + hardlockup_detector_hpet_enable(); +} -- 2.17.1