Re: [PATCH 3/7] vfio/pci: Use vfio_device_unmap_mapping_range()

Christoph Hellwig
2021-08-10T12:56:50Z

On Tue, Aug 10, 2021 at 08:57:22AM -0300, Jason Gunthorpe wrote:
> I'm not sure there is a real performance win to chase here? Doesn't
> this only protect mmap against reset? The mmap isn't performance
> sensitive, right?
>
> If this really needs extra optimization adding a rwsem to the devset
> and using that across the whole set would surely be sufficient.

Every mmio read or write takes memory_lock.