Re: [PATCH v8 4/5] Documentation: add debugfs description for vfio

[Alex Williamson]

On Fri, 17 Feb 2023 16:48:30 +0800
Longfang Liu <liulongfang@xxxxxxxxxx> wrote:

> Add two debugfs document description file to help users understand
> how to use the accelerator live migration driver's debugfs.
> 
> Signed-off-by: Longfang Liu <liulongfang@xxxxxxxxxx>
> ---
>  .../ABI/testing/debugfs-hisi-migration        | 28 +++++++++++++++++++
>  Documentation/ABI/testing/debugfs-vfio        | 17 +++++++++++
>  2 files changed, 45 insertions(+)
>  create mode 100644 Documentation/ABI/testing/debugfs-hisi-migration
>  create mode 100644 Documentation/ABI/testing/debugfs-vfio
> 
> diff --git a/Documentation/ABI/testing/debugfs-hisi-migration b/Documentation/ABI/testing/debugfs-hisi-migration
> new file mode 100644
> index 000000000000..0f45f30ff6d4
> --- /dev/null
> +++ b/Documentation/ABI/testing/debugfs-hisi-migration
> @@ -0,0 +1,28 @@
> +What:		/sys/kernel/debug/vfio/<bdf>/migration_data

s/bdf/name/ throughout.

> +Date:		Feb 2023
> +KernelVersion:  6.2
> +Contact:	linux-kernel@xxxxxxxxxxxxxxx

Is there not someone at Huawei willing to be the contact point for the
hisi_acc specific attributes?

> +Description:	Read the live migration data of the vfio device.
> +		The output format of the data is defined by the live
> +		migration driver.
> +
> +What:		/sys/kernel/debug/vfio/<bdf>/migration_attr
> +Date:		Feb 2023
> +KernelVersion:  6.2
> +Contact:	linux-kernel@xxxxxxxxxxxxxxx
> +Description:	Read the live migration attributes of the vfio device.
> +		The output format of the attributes is defined by the live
> +		migration driver.
> +
> +What:		/sys/kernel/debug/vfio/<bdf>/migration_debug
> +Date:		Feb 2023
> +KernelVersion:  6.2
> +Contact:	linux-kernel@xxxxxxxxxxxxxxx
> +Description:	This debug file supports "echo" command	write operations.
> +		The command is actually represented by an integer number, and the
> +		specific meaning is defined by the corresponding device driver.
> +		For example, three commands are defined in the HiSilicon accelerator
> +		live migration driver:
> +		0: State save
> +		1: State resume
> +		2: IO test
> diff --git a/Documentation/ABI/testing/debugfs-vfio b/Documentation/ABI/testing/debugfs-vfio
> new file mode 100644
> index 000000000000..e22531d16674
> --- /dev/null
> +++ b/Documentation/ABI/testing/debugfs-vfio
> @@ -0,0 +1,17 @@
> +What:		/sys/kernel/debug/vfio
> +Date:		Feb 2023
> +KernelVersion:  6.2
> +Contact:	linux-kernel@xxxxxxxxxxxxxxx

These should likely at least be the kvm list as the official list of
vfio if you're not interested in being the contact point.

Thanks,
Alex

> +Description:	This debugfs file directory is used for debugging
> +		of vfio devices that support live migration.
> +		Each device that supports live migration can create a device
> +		subdirectory under this directory by referencing the public
> +		registration interface.
> +
> +What:		/sys/kernel/debug/vfio/<bdf>/migration_state
> +Date:		Feb 2023
> +KernelVersion:  6.2
> +Contact:	linux-kernel@xxxxxxxxxxxxxxx
> +Description:	Read the live migration status of the vfio device.
> +		The status of these live migrations includes:
> +		ERROR, RUNNING, STOP, STOP_COPY, RESUMING.