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=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 6A471C43603 for ; Wed, 4 Dec 2019 17:18:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 471B3207DD for ; Wed, 4 Dec 2019 17:18:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728137AbfLDRSa (ORCPT ); Wed, 4 Dec 2019 12:18:30 -0500 Received: from mga03.intel.com ([134.134.136.65]:36334 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727828AbfLDRS3 (ORCPT ); Wed, 4 Dec 2019 12:18:29 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orsmga103.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 04 Dec 2019 09:18:28 -0800 X-IronPort-AV: E=Sophos;i="5.69,278,1571727600"; d="scan'208";a="361634696" Received: from ahduyck-desk1.jf.intel.com ([10.7.198.76]) by orsmga004-auth.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 04 Dec 2019 09:18:28 -0800 Message-ID: Subject: Re: [PATCH] driver core: Fix test_async_driver_probe if NUMA is disabled From: Alexander Duyck To: Guenter Roeck , Greg Kroah-Hartman Cc: "Rafael J . Wysocki" , linux-kernel@vger.kernel.org Date: Wed, 04 Dec 2019 09:18:28 -0800 In-Reply-To: References: <20191127202453.28087-1-linux@roeck-us.net> <4a2aa8554933c2d004761d5f3e8132018be5ea27.camel@linux.intel.com> <377feb00-9288-e03c-b8a7-26ba87e24927@roeck-us.net> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.32.5 (3.32.5-1.fc30) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2019-11-27 at 16:33 -0800, Guenter Roeck wrote: > On 11/27/19 3:13 PM, Alexander Duyck wrote: > > On Wed, 2019-11-27 at 14:42 -0800, Guenter Roeck wrote: > > > On 11/27/19 1:24 PM, Alexander Duyck wrote: > > > > On Wed, 2019-11-27 at 12:24 -0800, Guenter Roeck wrote: > > > > > Since commit 57ea974fb871 ("driver core: Rewrite test_async_driver_probe > > > > > to cover serialization and NUMA affinity"), running the test with NUMA > > > > > disabled results in warning messages similar to the following. > > > > > > > > > > test_async_driver test_async_driver.12: NUMA node mismatch -1 != 0 > > > > > > > > > > If CONFIG_NUMA=n, dev_to_node(dev) returns -1, and numa_node_id() > > > > > returns 0. Both are widely used, so it appears risky to change return > > > > > values. Augment the check with IS_ENABLED(CONFIG_NUMA) instead > > > > > to fix the problem. > > > > > > > > > > Cc: Alexander Duyck > > > > > Fixes: 57ea974fb871 ("driver core: Rewrite test_async_driver_probe to cover serialization and NUMA affinity") > > > > > Signed-off-by: Guenter Roeck > > > > > --- > > > > > drivers/base/test/test_async_driver_probe.c | 3 ++- > > > > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > > > > > > > diff --git a/drivers/base/test/test_async_driver_probe.c b/drivers/base/test/test_async_driver_probe.c > > > > > index f4b1d8e54daf..3bb7beb127a9 100644 > > > > > --- a/drivers/base/test/test_async_driver_probe.c > > > > > +++ b/drivers/base/test/test_async_driver_probe.c > > > > > @@ -44,7 +44,8 @@ static int test_probe(struct platform_device *pdev) > > > > > * performing an async init on that node. > > > > > */ > > > > > if (dev->driver->probe_type == PROBE_PREFER_ASYNCHRONOUS) { > > > > > - if (dev_to_node(dev) != numa_node_id()) { > > > > > + if (IS_ENABLED(CONFIG_NUMA) && > > > > > + dev_to_node(dev) != numa_node_id()) { > > > > > dev_warn(dev, "NUMA node mismatch %d != %d\n", > > > > > dev_to_node(dev), numa_node_id()); > > > > > atomic_inc(&warnings); > > > > > > > > I'm not sure that is really the correct fix. It might be better to test it > > > > against NUMA_NO_NODE and then if it is not that make sure that it matches > > > > the node ID. Adding the check against NUMA_NO_NODE would resolve the issue > > > > for cases where the device might be assigned to multiple NUMA nodes. > > > > > > > I think you are suggesting that dev_to_node(dev) might return NUMA_NO_NODE > > > even on systems with CONFIG_NUMA enabled. I have no idea if that can happen. > > > The code in test_async_probe_init() seems to suggest that the node is set > > > to a valid node id for all asynchronous nodes, so I don't immediately see > > > how that could be the case. I may be missing something, of course. > > > > Well thinking back to the Nehalem architecture I seem to recall that there > > were devices that were connected to a shared IOH that was accessible > > across both nodes. I thought that they might have a node ID of > > NUMA_NO_NODE since they didn't really belong to either of the two nodes in > > the sytem. > > > > It would effectively work out the same as your patch compiler wise since > > dev_to_node would be NUMA_NO_NODE in the non-NUMA case so it would compile > > out the warning since it would fail the first check, and in the NUMA case > > it would add an extra check to make sure that dev_to_node is actually > > indicating the device needs a specific node in the NUMA enabled case. > > > > I thought the code is specifically checking devices which it previously > created, which are well defined and understood test devices. After all, > the check is in the test driver's probe function. Guess I really don't > understand the code. Please take my patch as bug report, and submit > whatever fix you think is correct. Sorry I had overlooked that this is the test code. I suppose it should be fine since we specify the node ID for all instances where we register an asychronous test device. Thanks. - Alex