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 1E57BC7618E for ; Fri, 21 Apr 2023 03:33:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232327AbjDUDdE (ORCPT ); Thu, 20 Apr 2023 23:33:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41298 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233498AbjDUDcz (ORCPT ); Thu, 20 Apr 2023 23:32:55 -0400 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E005F2712 for ; Thu, 20 Apr 2023 20:32:49 -0700 (PDT) Received: from kwepemm600005.china.huawei.com (unknown [172.30.72.53]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4Q2g3y4GmVz17WMn; Fri, 21 Apr 2023 11:29:02 +0800 (CST) Received: from [10.67.103.158] (10.67.103.158) by kwepemm600005.china.huawei.com (7.193.23.191) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.23; Fri, 21 Apr 2023 11:32:47 +0800 Subject: Re: [PATCH v10 3/5] hisi_acc_vfio_pci: register debugfs for hisilicon migration driver From: liulongfang To: Jason Gunthorpe CC: , , , , , References: <20230408074224.62608-1-liulongfang@huawei.com> <20230408074224.62608-4-liulongfang@huawei.com> Message-ID: <81e11acf-0ede-d515-bb5a-3964c302f384@huawei.com> Date: Fri, 21 Apr 2023 11:32:47 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="gbk" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.67.103.158] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To kwepemm600005.china.huawei.com (7.193.23.191) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2023/4/21 11:27, liulongfang wrote: > On 2023/4/14 20:24, Jason Gunthorpe wrote: >> On Sat, Apr 08, 2023 at 03:42:22PM +0800, Longfang Liu wrote: >>> +static int hisi_acc_vf_debug_restore(struct seq_file *seq, void *data) >>> +{ >>> + struct device *vf_dev = seq->private; >>> + struct vfio_pci_core_device *core_device = dev_get_drvdata(vf_dev); >>> + struct vfio_device *vdev = &core_device->vdev; >>> + struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev); >>> + struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf; >>> + int ret; >>> + >>> + ret = hisi_acc_vf_debug_check(seq, vdev); >>> + if (ret) >>> + goto restore_err; >>> + >>> + ret = vf_qm_state_save(hisi_acc_vdev, migf); >>> + if (ret) { >>> + seq_printf(seq, "%s\n", "failed to save device data!"); >>> + goto restore_err; >>> + } >>> + >>> + ret = vf_qm_check_match(hisi_acc_vdev, migf); >>> + if (ret) { >>> + seq_printf(seq, "%s\n", "failed to match the VF!"); >>> + goto restore_err; >>> + } >>> + >>> + ret = vf_qm_load_data(hisi_acc_vdev, migf); >>> + if (ret) { >>> + seq_printf(seq, "%s\n", "failed to recover the VF!"); >>> + goto restore_err; >>> + } >>> + >>> + vf_qm_fun_reset(&hisi_acc_vdev->vf_qm); >>> + seq_printf(seq, "%s\n", "successful to resume device data!"); >>> + >>> +restore_err: >>> + return 0; >>> +} >> >> This is basically an in-kernel self test, it should be protected with >> some kind of VFIO selftest kconfig. >> > As a debugfs function, its usage will be more flexible for users. > >> Though, I wonder why we need it??? > After a live migration error occurs. Through this debugfs function, > you can perform separate functional tests on the source and destination > to locate the cause of the error. > > Can't you write a trivial userspace >> program under tools/testing to do this sequence with the ioctls? >> > Sorry, I still wish this feature was a simple debugfs feature. > If you want the userspace testing tool you mentioned, > you can try it on mlx5. > > Thanks, > Longfang. >>> +static int hisi_acc_vf_debug_save(struct seq_file *seq, void *data) >>> +{ >>> + struct device *vf_dev = seq->private; >>> + struct vfio_pci_core_device *core_device = dev_get_drvdata(vf_dev); >>> + struct vfio_device *vdev = &core_device->vdev; >>> + struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev); >>> + struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf; >>> + int ret; >>> + >>> + ret = hisi_acc_vf_debug_check(seq, vdev); >>> + if (ret) >>> + goto save_err; >>> + >>> + ret = vf_qm_state_save(hisi_acc_vdev, migf); >>> + if (ret) { >>> + seq_printf(seq, "%s\n", "failed to save device data!"); >>> + goto save_err; >>> + } >>> + seq_printf(seq, "%s\n", "successful to save device data!"); >>> + >>> +save_err: >>> + return 0; >>> +} >> >> Same kind of commen there, this is a selftest, why does it need a >> special kernel interface? >> >> .. and so on.. >> >> I thought the non-selftesty bits were OK, maybe split the patch to >> match progress >> Thank you for your suggestion, but the current debugfs method can already meet the functional requirements of verification testing and problem location. Thanks, Longfang. >> Jason >> . >>