[Intel-gfx] [PATCH] drm/i915/gtt: Allocate va range only if vma is not bound

[Mika Kuoppala]

When we have bound vma into an address space, the layout
of page table structures is immutable. So we can be absolutely
certain that if vma is already bound, there is no need to
(re)allocate a virtual address range for it.

v2: - add sanity checks and remove superfluous GLOBAL_BIND set
    - we might do update for an unbound vma (Chris)

v3: s/u32/unsigned (Chris)

Testcase: igt/gem_exec_big #bdw
Reported-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Michel Thierry <michel.thierry at intel.com>
Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
Signed-off-by: Mika Kuoppala <mika.kuoppala at intel.com>
Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_gem_gtt.c | 39 +++++++++++++++++++++----------------
 1 file changed, 22 insertions(+), 17 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 6fae6bd..85f27d6 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -1928,8 +1928,6 @@ static int ggtt_bind_vma(struct i915_vma *vma,
 		vma->vm->insert_entries(vma->vm, pages,
 					vma->node.start,
 					cache_level, pte_flags);
-
-		vma->bound |= GLOBAL_BIND;
 	}
 
 	if (dev_priv->mm.aliasing_ppgtt && flags & LOCAL_BIND) {
@@ -2804,21 +2802,13 @@ i915_get_ggtt_vma_pages(struct i915_vma *vma)
 int i915_vma_bind(struct i915_vma *vma, enum i915_cache_level cache_level,
 		  u32 flags)
 {
-	int ret = 0;
-	u32 bind_flags = 0;
-
-	if (vma->vm->allocate_va_range) {
-		trace_i915_va_alloc(vma->vm, vma->node.start,
-				    vma->node.size,
-				    VM_TO_TRACE_NAME(vma->vm));
+	int ret;
+	unsigned bind_flags;
 
-		ret = vma->vm->allocate_va_range(vma->vm,
-						 vma->node.start,
-						 vma->node.size);
-		if (ret)
-			return ret;
-	}
+	if (WARN_ON(flags == 0))
+		return -EINVAL;
 
+	bind_flags = 0;
 	if (flags & PIN_GLOBAL)
 		bind_flags |= GLOBAL_BIND;
 	if (flags & PIN_USER)
@@ -2829,8 +2819,23 @@ int i915_vma_bind(struct i915_vma *vma, enum i915_cache_level cache_level,
 	else
 		bind_flags &= ~vma->bound;
 
-	if (bind_flags)
-		ret = vma->vm->bind_vma(vma, cache_level, bind_flags);
+	if (bind_flags == 0)
+		return 0;
+
+	if (vma->bound == 0 && vma->vm->allocate_va_range) {
+		trace_i915_va_alloc(vma->vm,
+				    vma->node.start,
+				    vma->node.size,
+				    VM_TO_TRACE_NAME(vma->vm));
+
+		ret = vma->vm->allocate_va_range(vma->vm,
+						 vma->node.start,
+						 vma->node.size);
+		if (ret)
+			return ret;
+	}
+
+	ret = vma->vm->bind_vma(vma, cache_level, bind_flags);
 	if (ret)
 		return ret;
 
-- 
1.9.1