drm/i915/gem: Protect used framebuffers from casual eviction

In the shrinker, we protect framebuffers from light reclaim as we
typically expect framebuffers to be reused in the near future (and with
low latency requirements). We can apply the same logic to the GGTT
eviction and defer framebuffers to the second pass only used if the
caller is desperate enough to wait for space to become available.
In most cases, the caller will use a smaller partial vma instead of
trying to force the object into the GGTT if doing so will cause other
users to be evicted.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210119214336.1463-5-chris@chris-wilson.co.uk

1 files changed, 15 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/i915_vma.h b/drivers/gpu/drm/i915/i915_vma.h
index 5b3a3c653454..a64adc8c883b 100644
--- a/drivers/gpu/drm/i915/i915_vma.h
+++ b/drivers/gpu/drm/i915/i915_vma.h
@@ -363,6 +363,21 @@ i915_vma_unpin_fence(struct i915_vma *vma)
 
 void i915_vma_parked(struct intel_gt *gt);
 
+static inline bool i915_vma_is_scanout(const struct i915_vma *vma)
+{
+	return test_bit(I915_VMA_SCANOUT_BIT, __i915_vma_flags(vma));
+}
+
+static inline void i915_vma_mark_scanout(struct i915_vma *vma)
+{
+	set_bit(I915_VMA_SCANOUT_BIT, __i915_vma_flags(vma));
+}
+
+static inline void i915_vma_clear_scanout(struct i915_vma *vma)
+{
+	clear_bit(I915_VMA_SCANOUT_BIT, __i915_vma_flags(vma));
+}
+
 #define for_each_until(cond) if (cond) break; else
 
 /**