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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B514CE674A7 for ; Fri, 1 Nov 2024 05:48:01 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 4E1EF10E0D1; Fri, 1 Nov 2024 05:48:01 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="Ggrr6arG"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.19]) by gabe.freedesktop.org (Postfix) with ESMTPS id 7C88D10E0D1 for ; Fri, 1 Nov 2024 05:47:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1730440080; x=1761976080; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=leqz/2BPRu2JPcJMFHPwDhrsvb3qLo+LuENHV00WYdE=; b=Ggrr6arGYo5GJeuuSm78R6zcd9k6RLajSFAq0kunrvEYy3Xtu5RxNAGf VFlat0BgdbTC6MzjUKjyqZL6xUAoDLKfunsy4W0wmBZSZl2IhsvjhYE6l bLKW94lmFrEOOkRg8y4C4ZSieU0vqj29iLtXSyMZ+PXKlLklcN7T2gYUP yURfuBqciA5bNh//aiM4uotZp9EKBka9djJ3CttJawuZRGiBaCpksp9t1 NVjkMEyREI1Z6aDolGL1jWyGgaR9q/Cqb6WiixSfnoQWOi3zw5cfkAyQH 3lDLZHpZeSZH29FZvZI45tEufTVxNEq5m+v1zY4hWq2Poq/QR4H+YkJSC A==; X-CSE-ConnectionGUID: NT2GcNhfT+S6O/xnIeNttA== X-CSE-MsgGUID: YI6efiiKR5KoBjHZSH5EmA== X-IronPort-AV: E=McAfee;i="6700,10204,11222"; a="30063457" X-IronPort-AV: E=Sophos;i="6.11,199,1725346800"; d="scan'208";a="30063457" Received: from orviesa004.jf.intel.com ([10.64.159.144]) by orvoesa111.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Oct 2024 22:47:59 -0700 X-CSE-ConnectionGUID: hboW6i6qQb2id+hVEKhPRA== X-CSE-MsgGUID: M8KnILKZSEqkoiOVZURBnQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.11,248,1725346800"; d="scan'208";a="87993291" Received: from black.fi.intel.com ([10.237.72.28]) by orviesa004.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Oct 2024 22:47:57 -0700 Date: Fri, 1 Nov 2024 07:47:54 +0200 From: Raag Jadav To: Lucas De Marchi Cc: intel-xe@lists.freedesktop.org, John Harrison , Rodrigo Vivi , =?iso-8859-1?Q?Jos=E9?= Roberto de Souza Subject: Re: [PATCH 1/2] drm/xe: Improve devcoredump documentation Message-ID: References: <20241031182916.1441987-1-lucas.demarchi@intel.com> <20241031182916.1441987-2-lucas.demarchi@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241031182916.1441987-2-lucas.demarchi@intel.com> X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" On Thu, Oct 31, 2024 at 11:29:15AM -0700, Lucas De Marchi wrote: ... > - * Snapshot at hang: > - * The 'data' file is printed with a drm_printer pointer at devcoredump read > - * time. For this reason, we need to take snapshots from when the hang has > - * happened, and not only when the user is reading the file. Otherwise the > - * information is outdated since the resets might have happened in between. > + * The following characteristics are observed by xe when creating a device > + * coredump: > * > - * 'First' failure snapshot: > - * In general, the first hang is the most critical one since the following hangs > - * can be a consequence of the initial hang. For this reason we only take the > - * snapshot of the 'first' failure and ignore subsequent calls of this function, > - * at least while the coredump device is alive. Dev_coredump has a delayed work > - * queue that will eventually delete the device and free all the dump > - * information. > + * **Snapshot at hang**: > + * The 'data' file contains a snapshot of the HW state at the time the hang > + * happened. Due to the driver recovering from resets/crashes, it may not > + * correspond to the state of when the file is read by userspace. Does that mean the devcoredump will be present even after a successful recovery? Perhaps moving the 'release' part to above paragraph will add required context. > + * **First failure only**: > + * In general, the first hang is the most critical one since the following > + * hangs can be a consequence of the initial hang. For this reason a snapshot > + * is taken only for the first failure. Until the devcoredump is released by > + * userspace or kernel, all subsequent hangs do not override the snapshot nor > + * create new ones. Devcoredump has a delayed work queue that will eventually > + * delete the file node and free all the dump information. Raag