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 093B1FA3728 for ; Wed, 16 Oct 2019 22:08:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C75E72168B for ; Wed, 16 Oct 2019 22:08:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1571263685; bh=r4G5M8LqISPfavKPeJV3kNgvzavMX8YwB3Ihhw+YbsE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=gqHPYhD/Y0TfnPHzz4vE8YGI1vI1vhIt16i0gXQFcGV2XwsPR++k+2BCkUa1gFt2S OL5BrsH0ez9ub78y8snmUsFOJFOP6jNmhgZhrinmOBvuiRCCQfujCco7n/07GWcYDX 5NUC8QhNU85TaluZdVClVbgNGBCZrFNWKdX53Z3g= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2392541AbfJPWIF (ORCPT ); Wed, 16 Oct 2019 18:08:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:50988 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2438070AbfJPV5z (ORCPT ); Wed, 16 Oct 2019 17:57:55 -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 7FF2C21928; Wed, 16 Oct 2019 21:57:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1571263074; bh=r4G5M8LqISPfavKPeJV3kNgvzavMX8YwB3Ihhw+YbsE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fV7dQLTJCem+NWRW+HVCdMkbK5ne4OIw3MgN1l39CwhnhfCdypYMRMZN9gGVZ/3Mz GI3NpMhQQuOWFbFi1siJjsda23cOGyJDIlLnV6FuPhWFxz2IDOdIHvftiHqzVDc5fE Em5CMuPxAMa48QFM3Bh+7810wHt1tcoDPGota9Oo= 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 4.19 74/81] tracing/hwlat: Report total time spent in all NMIs during the sample Date: Wed, 16 Oct 2019 14:51:25 -0700 Message-Id: <20191016214847.440030578@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191016214805.727399379@linuxfoundation.org> References: <20191016214805.727399379@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 @@ -150,7 +150,7 @@ 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)