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 7F0C2C7618A for ; Mon, 20 Mar 2023 09:25:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231379AbjCTJZp (ORCPT ); Mon, 20 Mar 2023 05:25:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35784 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231222AbjCTJZO (ORCPT ); Mon, 20 Mar 2023 05:25:14 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A79281A646 for ; Mon, 20 Mar 2023 02:24:44 -0700 (PDT) Received: from kwepemm600005.china.huawei.com (unknown [172.30.72.55]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4Pg8Rz2PMTzrVNl; Mon, 20 Mar 2023 17:23:43 +0800 (CST) Received: from huawei.com (10.50.163.32) 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 15.1.2507.21; Mon, 20 Mar 2023 17:24:41 +0800 From: Longfang Liu To: , , , CC: , , , Subject: [PATCH v9 1/5] vfio/migration: Add debugfs to live migration driver Date: Mon, 20 Mar 2023 17:23:34 +0800 Message-ID: <20230320092338.2889-2-liulongfang@huawei.com> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20230320092338.2889-1-liulongfang@huawei.com> References: <20230320092338.2889-1-liulongfang@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.50.163.32] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) 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 There are multiple devices, software and operational steps involved in the process of live migration. An error occurred on any node may cause the live migration operation to fail. This complex process makes it very difficult to locate and analyze the cause when the function fails. In order to quickly locate the cause of the problem when the live migration fails, I added a set of debugfs to the vfio live migration driver. +-------------------------------------------+ | | | | | QEMU | | | | | +---+----------------------------+----------+ | ^ | ^ | | | | | | | | v | v | +---------+--+ +---------+--+ |src vfio_dev| |dst vfio_dev| +--+---------+ +--+---------+ | ^ | ^ | | | | v | | | +-----------+----+ +-----------+----+ |src dev debugfs | |dst dev debugfs | +----------------+ +----------------+ The entire debugfs directory will be based on the definition of the CONFIG_DEBUG_FS macro. If this macro is not enabled, the interfaces in vfio.h will be empty definitions, and the creation and initialization of the debugfs directory will not be executed. vfio | +--- | +---migration | +--state | +--hisi_acc | +--attr | +--data | +--debug | +--- +---migration +--state +--hisi_acc +--attr +--data +--debug debugfs will create a public root directory "vfio" file. then create a dev_name() file for each live migration device. First, create a unified state acquisition file of "migration" in this device directory. Then, create a public live migration state lookup file "state" Finally, create a directory file based on the device type, and then create the device's own debugging files under this directory file. Here, HiSilicon accelerator creates three debug files: attr: used to obtain the attribute parameters of the current live migration device. data: used to get the live migration data of the current live migration device. debug: Used to debug the current live migration device through commands. The live migration function of the current device can be tested by operating the debug files, and the functional status of the equipment and software at each stage can be tested step by step without performing the complete live migration function. And after the live migration is performed, the migration device data of the live migration can be obtained through the debug files. Signed-off-by: Longfang Liu --- drivers/vfio/Makefile | 2 +- drivers/vfio/vfio.h | 14 +++++++ drivers/vfio/vfio_debugfs.c | 80 +++++++++++++++++++++++++++++++++++++ drivers/vfio/vfio_main.c | 5 +++ include/linux/vfio.h | 8 ++++ 5 files changed, 108 insertions(+), 1 deletion(-) create mode 100644 drivers/vfio/vfio_debugfs.c diff --git a/drivers/vfio/Makefile b/drivers/vfio/Makefile index 70e7dcb302ef..1debcff31d30 100644 --- a/drivers/vfio/Makefile +++ b/drivers/vfio/Makefile @@ -7,7 +7,7 @@ vfio-y += vfio_main.o \ vfio-$(CONFIG_IOMMUFD) += iommufd.o vfio-$(CONFIG_VFIO_CONTAINER) += container.o vfio-$(CONFIG_VFIO_VIRQFD) += virqfd.o - +vfio-$(CONFIG_DEBUG_FS) += vfio_debugfs.o obj-$(CONFIG_VFIO_IOMMU_TYPE1) += vfio_iommu_type1.o obj-$(CONFIG_VFIO_IOMMU_SPAPR_TCE) += vfio_iommu_spapr_tce.o obj-$(CONFIG_VFIO_PCI) += pci/ diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h index e9721d8424bc..8e5cafa6aa3a 100644 --- a/drivers/vfio/vfio.h +++ b/drivers/vfio/vfio.h @@ -258,4 +258,18 @@ static inline void vfio_device_put_kvm(struct vfio_device *device) } #endif +#ifdef CONFIG_DEBUG_FS +void vfio_debugfs_create_root(void); +void vfio_debugfs_remove_root(void); + +void vfio_device_debugfs_init(struct vfio_device *vdev); +void vfio_device_debugfs_exit(struct vfio_device *vdev); +#else +static inline void vfio_debugfs_create_root(void) { } +static inline void vfio_debugfs_remove_root(void) { } + +static inline void vfio_device_debugfs_init(struct vfio_device *vdev) { } +static inline void vfio_device_debugfs_exit(struct vfio_device *vdev) { } +#endif /* CONFIG_DEBUG_FS */ + #endif diff --git a/drivers/vfio/vfio_debugfs.c b/drivers/vfio/vfio_debugfs.c new file mode 100644 index 000000000000..f5b6bf2a1d48 --- /dev/null +++ b/drivers/vfio/vfio_debugfs.c @@ -0,0 +1,80 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2023, HiSilicon Ltd. + */ + +#include +#include +#include +#include +#include "vfio.h" + +static struct dentry *vfio_debugfs_root; + +static int vfio_device_state_read(struct seq_file *seq, void *data) +{ + struct device *vf_dev = seq->private; + struct vfio_device *vdev = container_of(vf_dev, struct vfio_device, device); + enum vfio_device_mig_state state; + int ret; + + ret = vdev->mig_ops->migration_get_state(vdev, &state); + if (ret) + return -EINVAL; + + switch (state) { + case VFIO_DEVICE_STATE_RUNNING: + seq_printf(seq, "%s\n", "RUNNING"); + break; + case VFIO_DEVICE_STATE_STOP_COPY: + seq_printf(seq, "%s\n", "STOP_COPY"); + break; + case VFIO_DEVICE_STATE_STOP: + seq_printf(seq, "%s\n", "STOP"); + break; + case VFIO_DEVICE_STATE_RESUMING: + seq_printf(seq, "%s\n", "RESUMING"); + break; + case VFIO_DEVICE_STATE_RUNNING_P2P: + seq_printf(seq, "%s\n", "RESUMING_P2P"); + break; + case VFIO_DEVICE_STATE_ERROR: + seq_printf(seq, "%s\n", "ERROR"); + break; + default: + seq_printf(seq, "%s\n", "Invalid"); + } + + return 0; +} + +void vfio_device_debugfs_init(struct vfio_device *vdev) +{ + struct dentry *vfio_dev_migration = NULL; + struct device *dev = &vdev->device; + + vdev->debug_root = debugfs_create_dir(dev_name(vdev->dev), vfio_debugfs_root); + vfio_dev_migration = debugfs_create_dir("migration", vdev->debug_root); + + debugfs_create_devm_seqfile(dev, "state", vfio_dev_migration, + vfio_device_state_read); +} +EXPORT_SYMBOL_GPL(vfio_device_debugfs_init); + +void vfio_device_debugfs_exit(struct vfio_device *vdev) +{ + debugfs_remove_recursive(vdev->debug_root); +} +EXPORT_SYMBOL_GPL(vfio_device_debugfs_exit); + +void vfio_debugfs_create_root(void) +{ + vfio_debugfs_root = debugfs_create_dir("vfio", NULL); +} + +void vfio_debugfs_remove_root(void) +{ + debugfs_remove_recursive(vfio_debugfs_root); + vfio_debugfs_root = NULL; +} + diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c index 3a597e799918..09772fd3a396 100644 --- a/drivers/vfio/vfio_main.c +++ b/drivers/vfio/vfio_main.c @@ -1408,6 +1408,9 @@ static int __init vfio_init(void) } pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n"); + + vfio_debugfs_create_root(); + return 0; err_dev_class: @@ -1425,6 +1428,8 @@ static void __exit vfio_cleanup(void) vfio_virqfd_exit(); vfio_group_cleanup(); xa_destroy(&vfio_device_set_xa); + + vfio_debugfs_remove_root(); } module_init(vfio_init); diff --git a/include/linux/vfio.h b/include/linux/vfio.h index 93134b023968..fa6b898ebb58 100644 --- a/include/linux/vfio.h +++ b/include/linux/vfio.h @@ -63,6 +63,14 @@ struct vfio_device { struct iommufd_ctx *iommufd_ictx; bool iommufd_attached; #endif + +#ifdef CONFIG_DEBUG_FS + /* + * debug_root is a static property of the vfio_device + * which must be set prior to registering the vfio_device. + */ + struct dentry *debug_root; +#endif }; /** -- 2.24.0