Messages in this thread Patch in this message | | | Date | Mon, 16 Jan 2023 13:33:49 -0400 | From | Jason Gunthorpe <> | Subject | Re: [PATCH v6 1/5] vfio/migration: Add debugfs to live migration driver |
| |
On Sat, Jan 14, 2023 at 05:26:11PM +0800, Longfang Liu wrote: > 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 VF | | dst VF | > +-+------+ +-+------+ > | ^ | ^ > v | v | > +-------+-+------+ +-------+-+------+ > |Debugfs|state | |Debugfs|state | > +-------+--------+ +-------+--------+ > | debug_root | | debug_root | > +-------+--------+ +-------+--------+ > > 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_pci_debugfs.h will be empty definitions, > and the creation and initialization of the debugfs directory > will not be executed. > > debugfs will create a public root directory "vfio_mig" file. > then create a "debug_root" file for each live migration VF device. > state file: used to get the status of the live migration device. > debug_root: used to create your own custom debug files for live > migration device drivers. > > 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 <liulongfang@huawei.com> > --- > drivers/vfio/pci/Makefile | 1 + > drivers/vfio/pci/vfio_pci_core.c | 3 ++ > drivers/vfio/pci/vfio_pci_debugfs.c | 82 +++++++++++++++++++++++++++++ > drivers/vfio/pci/vfio_pci_debugfs.h | 30 +++++++++++ > include/linux/vfio.h | 6 +++ > 5 files changed, 122 insertions(+) > create mode 100644 drivers/vfio/pci/vfio_pci_debugfs.c > create mode 100644 drivers/vfio/pci/vfio_pci_debugfs.h > > diff --git a/drivers/vfio/pci/Makefile b/drivers/vfio/pci/Makefile > index 24c524224da5..75fe37e72e8d 100644 > --- a/drivers/vfio/pci/Makefile > +++ b/drivers/vfio/pci/Makefile > @@ -2,6 +2,7 @@ > > vfio-pci-core-y := vfio_pci_core.o vfio_pci_intrs.o vfio_pci_rdwr.o vfio_pci_config.o > vfio-pci-core-$(CONFIG_VFIO_PCI_ZDEV_KVM) += vfio_pci_zdev.o > +vfio-pci-core-$(CONFIG_DEBUG_FS) += vfio_pci_debugfs.o > obj-$(CONFIG_VFIO_PCI_CORE) += vfio-pci-core.o > > vfio-pci-y := vfio_pci.o > diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c > index f9365a5bc961..e85df2deb8e6 100644 > --- a/drivers/vfio/pci/vfio_pci_core.c > +++ b/drivers/vfio/pci/vfio_pci_core.c > @@ -31,6 +31,7 @@ > #include <asm/eeh.h> > #endif > > +#include "vfio_pci_debugfs.h" > #include "vfio_pci_priv.h" > > #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>" > @@ -2555,11 +2556,13 @@ EXPORT_SYMBOL_GPL(vfio_pci_core_set_params); > > static void vfio_pci_core_cleanup(void) > { > + vfio_pci_debugfs_remove_root(); > vfio_pci_uninit_perm_bits(); > } > > static int __init vfio_pci_core_init(void) > { > + vfio_pci_debugfs_create_root(); > /* Allocate shared config space permission data used by all devices */ > return vfio_pci_init_perm_bits(); > } > diff --git a/drivers/vfio/pci/vfio_pci_debugfs.c b/drivers/vfio/pci/vfio_pci_debugfs.c > new file mode 100644 > index 000000000000..169570de7ccb > --- /dev/null > +++ b/drivers/vfio/pci/vfio_pci_debugfs.c > @@ -0,0 +1,82 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (c) 2022, HiSilicon Ltd. > + */ > + > +#include <linux/pci.h> > +#include <linux/vfio_pci_core.h> > + > +#include "vfio_pci_debugfs.h" > + > +static struct dentry *vfio_pci_debugfs_root; > + > +static int vfio_pci_vf_state_read(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; > + enum vfio_device_mig_state state; > + int ret; > + > + ret = vdev->mig_ops->migration_get_state(vdev, &state); > + if (ret) { > + dev_err("failed to get device migration state");
Don't print
> + 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_pci_vf_debugfs_init(struct vfio_device *vdev) > +{ > + struct device *dev = vdev->dev; > + > + vdev->debug_root = debugfs_create_dir(dev_name(dev), vfio_pci_debugfs_root); > + > + debugfs_create_devm_seqfile(dev, "state", vdev->debug_root, > + vfio_pci_vf_state_read); > +} > +EXPORT_SYMBOL_GPL(vfio_pci_vf_debugfs_init); > + > +void vfio_pci_vf_debugfs_exit(struct vfio_device *vdev) > +{ > + debugfs_remove_recursive(vdev->debug_root); > +} > +EXPORT_SYMBOL_GPL(vfio_pci_vf_debugfs_exit); > + > +void vfio_pci_debugfs_create_root(void) > +{ > + vfio_pci_debugfs_root = debugfs_create_dir("vfio_mig", NULL); > +} > +EXPORT_SYMBOL_GPL(vfio_pci_debugfs_create_root); > + > +void vfio_pci_debugfs_remove_root(void) > +{ > + debugfs_remove_recursive(vfio_pci_debugfs_root); > + vfio_pci_debugfs_root = NULL; > +} > +EXPORT_SYMBOL_GPL(vfio_pci_debugfs_remove_root); > + > diff --git a/drivers/vfio/pci/vfio_pci_debugfs.h b/drivers/vfio/pci/vfio_pci_debugfs.h > new file mode 100644 > index 000000000000..8d1a4aef05db > --- /dev/null > +++ b/drivers/vfio/pci/vfio_pci_debugfs.h > @@ -0,0 +1,30 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* > + * vfio_pci_debugfs.h - VFIO migration debugfs interface > + * > + * Copyright (c) 2022, HiSilicon Ltd. > + * > + * Author: Longfang Liu <liulongfang@huawei.com> > + */ > + > +#ifndef __VFIO_PCI_DEBUGFS_H > +#define __VFIO_PCI_DEBUGFS_H > + > +#include <linux/debugfs.h> > +#include <linux/vfio.h> > + > +#ifdef CONFIG_DEBUG_FS > +void vfio_pci_debugfs_create_root(void); > +void vfio_pci_debugfs_remove_root(void);
extra whitespace
> +void vfio_pci_vf_debugfs_init(struct vfio_device *vdev); > +void vfio_pci_vf_debugfs_exit(struct vfio_device *vdev); > +#else > +static inline void vfio_pci_debugfs_create_root(void) { } > +static inline void vfio_pci_debugfs_remove_root(void) { } > + > +static inline void vfio_pci_vf_debugfs_init(struct vfio_device *vdev) { } > +static inline void vfio_pci_vf_debugfs_exit(struct vfio_device *vdev) { } > +#endif /* CONFIG_DEBUG_FS */
Just {}
> + > +#endif /* __VFIO_PCI_DEBUGFS_H */ > diff --git a/include/linux/vfio.h b/include/linux/vfio.h > index b4d5d4ca3d7d..7d6d02f165cf 100644 > --- a/include/linux/vfio.h > +++ b/include/linux/vfio.h > @@ -54,6 +54,12 @@ struct vfio_device { > struct completion comp; > struct list_head group_next; > struct list_head iommu_entry; > + > + /* > + * debug_root is a static property of the vfio_device > + * which must be set prior to registering the vfio_device. > + */ > + struct dentry *debug_root;
This should be ifdefd too if you are doing it like this
Jason
| |