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=-16.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 B56F4C433B4 for ; Wed, 19 May 2021 11:39:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 94FA56135C for ; Wed, 19 May 2021 11:39:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344153AbhESLkk (ORCPT ); Wed, 19 May 2021 07:40:40 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:60033 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238729AbhESLki (ORCPT ); Wed, 19 May 2021 07:40:38 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1621424358; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=lBcHZyfBnsktjuk8rKzUdYoE7fU2ywPjqDB2W+/BGHE=; b=DUuNEHnsIj+jOxASGXXgsg1c6ZxdE1fIrly/yw97/wgN37v9BurfeH2Rqyj7f+H6lJoazB O9jikwcXrg2G9E0x1AMr9wDFVP7gvbsytzquPDqoRA7YiAQ6o3uLV7kVcKUAm2dR8I1QzN M2KQ00bpzAKk9qxBLmDTGLDWFCid7UI= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-361-RsTqsp7-PzCrIKpex4FnmQ-1; Wed, 19 May 2021 07:39:16 -0400 X-MC-Unique: RsTqsp7-PzCrIKpex4FnmQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7193E6D582; Wed, 19 May 2021 11:39:14 +0000 (UTC) Received: from x1.com (ovpn-112-250.rdu2.redhat.com [10.10.112.250]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8822C687CC; Wed, 19 May 2021 11:38:53 +0000 (UTC) From: Daniel Bristot de Oliveira To: linux-kernel@vger.kernel.org, Steven Rostedt Cc: Tommaso Cucinotta , Kate Carcia , Daniel Bristot de Oliveira , Jonathan Corbet , Ingo Molnar , Mauro Carvalho Chehab , Thomas Gleixner , Peter Zijlstra , Will Deacon , Catalin Marinas , "Paul E. McKenney" , Joel Fernandes , Mathieu Desnoyers , Gabriele Paoloni , Juri Lelli , Clark Williams , linux-doc@vger.kernel.org Subject: [RFC PATCH 12/16] rv/reactors: Add the printk reactor Date: Wed, 19 May 2021 13:36:33 +0200 Message-Id: In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org Sample reactor that printks the reaction message. Note: do not use this reactor with rq_lock taken, it will lock the system until printk can handle that. Cc: Jonathan Corbet Cc: Steven Rostedt Cc: Ingo Molnar Cc: Mauro Carvalho Chehab Cc: Thomas Gleixner Cc: Peter Zijlstra Cc: Will Deacon Cc: Catalin Marinas Cc: "Paul E. McKenney" Cc: Joel Fernandes Cc: Mathieu Desnoyers Cc: Gabriele Paoloni Cc: Juri Lelli Cc: Clark Williams Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira --- kernel/trace/rv/Kconfig | 8 ++++++ kernel/trace/rv/Makefile | 3 ++- kernel/trace/rv/reactors/printk.c | 43 +++++++++++++++++++++++++++++++ 3 files changed, 53 insertions(+), 1 deletion(-) create mode 100644 kernel/trace/rv/reactors/printk.c diff --git a/kernel/trace/rv/Kconfig b/kernel/trace/rv/Kconfig index 612b36b97663..6cbfb0f9cf76 100644 --- a/kernel/trace/rv/Kconfig +++ b/kernel/trace/rv/Kconfig @@ -38,4 +38,12 @@ config RV_REACTORS tracing reactions, printing the monitor output via tracepoints, but other reactions can be added (on-demand) via this interface. +config RV_REACT_PRINTK + tristate "Printk reactor" + depends on RV_REACTORS + default y if RV_REACTORS + help + Enables the printk reactor. The printk reactor emmits a printk() + message if an exception is found. + endif # RV diff --git a/kernel/trace/rv/Makefile b/kernel/trace/rv/Makefile index af0ff9a46418..a57cb3c3d410 100644 --- a/kernel/trace/rv/Makefile +++ b/kernel/trace/rv/Makefile @@ -1,6 +1,7 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_RV) += rv.o -obj-$(CONFIG_RV_REACTORS) += rv_reactors.o obj-$(CONFIG_RV_MON_WIP) += monitors/wip/wip.o obj-$(CONFIG_RV_MON_WWNR) += monitors/wwnr/wwnr.o +obj-$(CONFIG_RV_REACTORS) += rv_reactors.o +obj-$(CONFIG_RV_REACT_PRINTK) += reactors/printk.o diff --git a/kernel/trace/rv/reactors/printk.c b/kernel/trace/rv/reactors/printk.c new file mode 100644 index 000000000000..f929eead6000 --- /dev/null +++ b/kernel/trace/rv/reactors/printk.c @@ -0,0 +1,43 @@ +/* + * Printk RV reactor: + * Prints the exception msg to the kernel message log. + * + * Copyright (C) 2019-2021 Daniel Bristot de Oliveira + * + * SPDX-License-Identifier: GPL-2.0 + */ +#include +#include +#include +#include +#include +#include + +static void rv_printk_reaction(char *msg) +{ + printk(msg); +} + +struct rv_reactor rv_printk = { + .name = "printk", + .description = "prints the exception msg to the kernel message log", + .react = rv_printk_reaction +}; + +int register_react_printk(void) +{ + rv_register_reactor(&rv_printk); + return 0; +} + +void unregister_react_printk(void) +{ + rv_unregister_reactor(&rv_printk); +} + +module_init(register_react_printk); +module_exit(unregister_react_printk); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Daniel Bristot de Oliveira"); +MODULE_DESCRIPTION("printk rv reactor: printk if an exception is hit"); -- 2.26.2