On Fri, Nov 04, 2022 at 11:22:51AM +0800, liulongfang wrote: > On 2022/11/4 4:21, Alex Williamson wrote: > > [Cc +kvm list] > > > > On Wed, 19 Oct 2022 16:10:32 +0800 > > Longfang Liu <liulongfang@xxxxxxxxxx> 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 accelerator > >> live migration driver. > >> > >> +-----------------------------------+ > >> | | > >> | QEMU | > >> | | > >> +---+--^--------------------+--^----+ > >> | | | | > >> | | | | > >> +---v--+----+ +---v--+----+ > >> | | | | > >> | src VF | | dest VF | > >> | | | | > >> +---+--^----+ +---+--^----+ > >> | | | | > >> | | | | > >> +---v--+----+ +---v--+----+ > >> | Debugfs | | Debugfs | > >> +-----+-----+ +-----+-----+ > >> |state|debug| |state|debug| > >> +-----+-----+ +-----+-----+ > >> > >> This set of debugfs will create two files for each VF device: > >> a state file and a debug file. > >> > >> The migration status of the current VF device can be obtained by > >> reading the status file. > >> > >> The live migration function of the current device can be tested by > >> operating the debug file, 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 file. > > > > This is proposed as an hisi_vfio_acc specific debugfs interface, but > > common code could certainly implement much of this as well. Should we > > have generic support for debugfs? > > > > OK, I'd love to extend this part of the debugfs functionality into the > vfio framework and make it a common debugfs functionality for all > device drivers that use live migration. Yeah, it is an interesting idea for sure Jason
