From: Chris Wilson chris.p.wilson@intel.com

Don't flush TLBs when the buffer is only used in the GGTT under full control of the kernel, as there's no risk of concurrent access and stale access from prefetch.

We only need to invalidate the TLB if they are accessible by the user. That helps to reduce the performance regression introduced by TLB invalidate logic.

Cc: stable@vger.kernel.org Fixes: 7938d61591d3 ("drm/i915: Flush TLBs before releasing backing store") Signed-off-by: Chris Wilson chris.p.wilson@intel.com Cc: Fei Yang fei.yang@intel.com Cc: Andi Shyti andi.shyti@linux.intel.com Acked-by: Thomas Hellström thomas.hellstrom@linux.intel.com Signed-off-by: Mauro Carvalho Chehab mchehab@kernel.org ---

See [PATCH 00/21] at: https://lore.kernel.org/all/cover.1657703926.git.mchehab@kernel.org/

drivers/gpu/drm/i915/i915_vma.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c index ef3b04c7e153..646f419b2035 100644 --- a/drivers/gpu/drm/i915/i915_vma.c +++ b/drivers/gpu/drm/i915/i915_vma.c @@ -538,7 +538,8 @@ int i915_vma_bind(struct i915_vma *vma, bind_flags); }

- set_bit(I915_BO_WAS_BOUND_BIT, &vma->obj->flags); + if (bind_flags & I915_VMA_LOCAL_BIND) + set_bit(I915_BO_WAS_BOUND_BIT, &vma->obj->flags);

atomic_or(bind_flags, &vma->flags); return 0;