On 17/12/2021 14:52, Thomas Hellström wrote:
Protect updates of struct i915_vma flags and async binding / unbinding with the vm::mutex. This means that i915_vma_bind() needs to assert vm::mutex held. In order to make that possible drop the caching of kmap_atomic() maps around i915_vma_bind(). An alternative would be to use kmap_local() but since we block cpu unplugging during sleeps inside kmap_local() sections this may have unwanted side-effects. Particularly since we might wait for gpu while holding the vm mutex. This change may theoretically increase execbuf cpu-usage on snb, but at least on non-highmem systems that increase should be very small. Signed-off-by: Thomas Hellström <thomas.hellstrom@xxxxxxxxxxxxxxx>
Reviewed-by: Matthew Auld <matthew.auld@xxxxxxxxx>