Am 01.03.2016 um 09:36 schrieb Maarten Lankhorst:
Op 29-02-16 om 23:13 schreef Gustavo Padovan:
2016-02-29 Alex Deucher alexdeucher@gmail.com:
From: Christian König christian.koenig@amd.com
A fence is never later than itself. This caused a bunch of overhead for AMDGPU.
v2: simplify check as suggested by Michel.
Signed-off-by: Christian König christian.koenig@amd.com Reviewed-by: Michel Dänzer michel.daenzer@amd.com Reviewed-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com
include/linux/fence.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
Reviewed-by: Gustavo Padovan gustavo.padovan@collabora.co.uk
Gustavo
Why is it causing overhead? Not really opposed to the patch though.
We tested if flushing the VM is necessary by remembering the last flushed VM update operation and comparing that to what operation we need to have flushed for the current command submission to work.
So when we where already at the last operation in the timeline we would flush anyway which was superfluous.
Regards, Christian.