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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 06A0EECE599 for ; Wed, 16 Oct 2019 22:15:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C707D2168B for ; Wed, 16 Oct 2019 22:15:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1571264115; bh=R7muj0ZQtz28cz8Rdo20VjZVXN0cWVxoYOowSW3clsY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=jY1uEn9Z5e3Jkr2MzAGixfxbsPDuRKtFxXJh3ulJy3k7NmIoGq+akRKjCo7tn64Uq zDVSNB/Zo/5C2pQunPEGVqvOhcMRvhtn9zupyPbk3LTQLBmNt3d5fDe+NRC3WNibjs eMsyh+tgSR9M1DYYAmUqpZkztu9H4/GZWmLwAkx0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2393337AbfJPWPO (ORCPT ); Wed, 16 Oct 2019 18:15:14 -0400 Received: from mail.kernel.org ([198.145.29.99]:46160 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2395220AbfJPVz2 (ORCPT ); Wed, 16 Oct 2019 17:55:28 -0400 Received: from localhost (unknown [192.55.54.58]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3674720872; Wed, 16 Oct 2019 21:55:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1571262928; bh=R7muj0ZQtz28cz8Rdo20VjZVXN0cWVxoYOowSW3clsY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qoAHQRIKBAorgKbjy/GiIXiFR6JpQeBI3RgzCHSa5bcLJJDX1A6krKiCVTMCO/8sE dWYLA4scygYS3GFi0M6TX3D1tPhqdzl2Fd32T9+iONdA0TL+35kD6EjapnyWq0tAET PyKvrB4gfHSeasV1uy5mhhL7/3GF8U1txOQKk/zs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Srivatsa S. Bhat (VMware)" , "Steven Rostedt (VMware)" Subject: [PATCH 4.9 88/92] tracing/hwlat: Report total time spent in all NMIs during the sample Date: Wed, 16 Oct 2019 14:51:01 -0700 Message-Id: <20191016214848.472113499@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191016214759.600329427@linuxfoundation.org> References: <20191016214759.600329427@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Srivatsa S. Bhat (VMware) commit 98dc19c11470ee6048aba723d77079ad2cda8a52 upstream. nmi_total_ts is supposed to record the total time spent in *all* NMIs that occur on the given CPU during the (active portion of the) sampling window. However, the code seems to be overwriting this variable for each NMI, thereby only recording the time spent in the most recent NMI. Fix it by accumulating the duration instead. Link: http://lkml.kernel.org/r/157073343544.17189.13911783866738671133.stgit@srivatsa-ubuntu Fixes: 7b2c86250122 ("tracing: Add NMI tracing in hwlat detector") Cc: stable@vger.kernel.org Signed-off-by: Srivatsa S. Bhat (VMware) Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman --- kernel/trace/trace_hwlat.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/trace/trace_hwlat.c +++ b/kernel/trace/trace_hwlat.c @@ -151,7 +151,7 @@ void trace_hwlat_callback(bool enter) if (enter) nmi_ts_start = time_get(); else - nmi_total_ts = time_get() - nmi_ts_start; + nmi_total_ts += time_get() - nmi_ts_start; } if (enter)