On Fri, Jul 23, 2021 at 10:12:08AM +0200, Christoph Hellwig wrote: > On Tue, Jul 20, 2021 at 02:42:56PM -0300, Jason Gunthorpe wrote: > > Like vfio_pci_try_bus_reset() this code wants to reset all of the devices > > in the "reset group" which is the same membership as the device set. > > > > Instead of trying to reconstruct the device set from the PCI list go > > directly from the device set's device list to execute the reset. > > > > The same basic structure as vfio_pci_try_bus_reset() is used. The > > 'vfio_devices' struct is replaced with the device set linked list and we > > simply sweep it multiple times under the lock. > > > > This eliminates a memory allocation and get/put traffic and another > > improperly locked test of pci_dev_driver(). > > Looks fine. But oh gad is that locking scheme awful.. I hope that the address space patches Alex has been working on will help this. And as I wrote it I was wondering if we can swap the dev_set lock for all these other locks and just delete the whole thing.. Thanks, Jason
