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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 128F5C433F5 for ; Sat, 12 Feb 2022 07:04:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232303AbiBLHE2 (ORCPT ); Sat, 12 Feb 2022 02:04:28 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:59458 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229720AbiBLHEY (ORCPT ); Sat, 12 Feb 2022 02:04:24 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EA0AE2716D; Fri, 11 Feb 2022 23:04:21 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id A9178B816F9; Sat, 12 Feb 2022 07:04:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0E6ABC340E7; Sat, 12 Feb 2022 07:04:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1644649459; bh=5JR5bOcysOJSDhFqg8hYnCFWbBwyk5yff/mZFGN/g14=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=rfy74ZkfFcQ+kcqFIyQLj/N5y9ufjm8AT5DYj4lCEUJOyzf7tTiYvBvOu6TPWVRbz /zy7BHaB9LQtbocZDeokNetYzUVKmZ1QIWSAojXQSG3zaWWbCB3vQrTJig+qhXhh8c QbPntvOB+fNg8ctNwIM4ahKsim82DJ0htqVSL+6U= Date: Sat, 12 Feb 2022 08:04:11 +0100 From: Greg KH To: Abhinav Kumar Cc: johannes@sipsolutions.net, linux-kernel@vger.kernel.org, rafael@kernel.org, robdclark@gmail.com, dri-devel@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, freedreno@lists.freedesktop.org, seanpaul@chromium.org, swboyd@chromium.org, nganji@codeaurora.org, aravindh@codeaurora.org, khsieh@codeaurora.org, daniel@ffwll.ch, dmitry.baryshkov@linaro.org Subject: Re: [PATCH] devcoredump: increase the device delete timeout to 10 mins Message-ID: References: <1644349472-31077-1-git-send-email-quic_abhinavk@quicinc.com> <654d620b-9e14-c47f-b48c-762dc0bd32a1@quicinc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <654d620b-9e14-c47f-b48c-762dc0bd32a1@quicinc.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 11, 2022 at 10:59:39AM -0800, Abhinav Kumar wrote: > Hi Greg > > Thanks for the response. > > On 2/11/2022 3:09 AM, Greg KH wrote: > > On Tue, Feb 08, 2022 at 11:44:32AM -0800, Abhinav Kumar wrote: > > > There are cases where depending on the size of the devcoredump and the speed > > > at which the usermode reads the dump, it can take longer than the current 5 mins > > > timeout. > > > > > > This can lead to incomplete dumps as the device is deleted once the timeout expires. > > > > > > One example is below where it took 6 mins for the devcoredump to be completely read. > > > > > > 04:22:24.668 23916 23994 I HWDeviceDRM::DumpDebugData: Opening /sys/class/devcoredump/devcd6/data > > > 04:28:35.377 23916 23994 W HWDeviceDRM::DumpDebugData: Freeing devcoredump node > > > > What makes this so slow? Reading from the kernel shouldn't be the > > limit, is it where the data is being sent to? > > We are still checking this. We are seeing better read times when we bump up > the thread priority of the thread which was reading this. Where is the thread sending the data to? > We are also trying to check if bumping up CPU speed is helping. > But, results have not been consistently good enough. So we thought we should > also increase the timeout to be safe. Why would 10 minutes be better than 30? What should the limit be? :) thanks, greg k-h