[PATCH 39/50] drm/i915: Dynamically allocate the array of drm_i915_gem_fence_reg

Chris Wilson chris at chris-wilson.co.uk
Wed Jul 4 18:31:20 UTC 2018


If we dynamically allocate the correct sized array for the fence
registers, we can avoid the 4x overallocation on older, typically
smaller devices and avoid having to know the static layout in advance.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_gem.c           | 33 ------------
 drivers/gpu/drm/i915/i915_gem_fence_reg.h |  2 -
 drivers/gpu/drm/i915/i915_gem_gtt.c       | 64 +++++++++++++++++++++--
 drivers/gpu/drm/i915/i915_gem_gtt.h       |  3 +-
 drivers/gpu/drm/i915/i915_vma.h           |  1 +
 5 files changed, 62 insertions(+), 41 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 171445917c5e..af2095f72bbb 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -5653,39 +5653,6 @@ i915_gem_cleanup_engines(struct drm_i915_private *dev_priv)
 		dev_priv->gt.cleanup_engine(engine);
 }
 
-void i915_ggtt_init_fences(struct i915_ggtt *ggtt)
-{
-	struct drm_i915_private *dev_priv = ggtt->vm.i915;
-	int i;
-
-	if (INTEL_GEN(dev_priv) >= 7 && !IS_VALLEYVIEW(dev_priv) &&
-	    !IS_CHERRYVIEW(dev_priv))
-		ggtt->num_fence_regs = 32;
-	else if (INTEL_GEN(dev_priv) >= 4 ||
-		 IS_I945G(dev_priv) || IS_I945GM(dev_priv) ||
-		 IS_G33(dev_priv) || IS_PINEVIEW(dev_priv))
-		ggtt->num_fence_regs = 16;
-	else
-		ggtt->num_fence_regs = 8;
-
-	if (intel_vgpu_active(dev_priv))
-		ggtt->num_fence_regs = I915_READ(vgtif_reg(avail_rs.fence_num));
-
-	INIT_LIST_HEAD(&ggtt->fence_list);
-
-	/* Initialize fence registers to zero */
-	for (i = 0; i < ggtt->num_fence_regs; i++) {
-		struct drm_i915_fence_reg *fence = &ggtt->fence_regs[i];
-
-		fence->ggtt = ggtt;
-		fence->id = i;
-		list_add_tail(&fence->link, &ggtt->fence_list);
-	}
-	i915_gem_restore_fences(dev_priv);
-
-	i915_gem_detect_bit_6_swizzle(dev_priv);
-}
-
 static void i915_gem_init__mm(struct drm_i915_private *i915)
 {
 	spin_lock_init(&i915->mm.object_stat_lock);
diff --git a/drivers/gpu/drm/i915/i915_gem_fence_reg.h b/drivers/gpu/drm/i915/i915_gem_fence_reg.h
index c510f8efc1bb..6e66f6b3f851 100644
--- a/drivers/gpu/drm/i915/i915_gem_fence_reg.h
+++ b/drivers/gpu/drm/i915/i915_gem_fence_reg.h
@@ -56,8 +56,6 @@ struct drm_i915_fence_reg {
 	bool dirty;
 };
 
-void i915_ggtt_init_fences(struct i915_ggtt *ggtt);
-
 struct drm_i915_fence_reg *
 i915_reserve_fence(struct drm_i915_private *i915);
 void i915_unreserve_fence(struct drm_i915_fence_reg *fence);
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 1cc38465bc0e..abd9e7057ada 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -37,6 +37,7 @@
 #include <drm/i915_drm.h>
 
 #include "i915_drv.h"
+#include "i915_gem_fence_reg.h"
 #include "i915_vgpu.h"
 #include "i915_trace.h"
 #include "intel_drv.h"
@@ -2924,6 +2925,51 @@ void i915_gem_fini_aliasing_ppgtt(struct drm_i915_private *i915)
 	ggtt->vm.vma_ops.unbind_vma = ggtt_unbind_vma;
 }
 
+static int i915_ggtt_init_fences(struct i915_ggtt *ggtt)
+{
+	struct drm_i915_private *dev_priv = ggtt->vm.i915;
+	int i;
+
+	if (INTEL_GEN(dev_priv) >= 7 &&
+	    !(IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)))
+		ggtt->num_fence_regs = 32;
+	else if (INTEL_GEN(dev_priv) >= 4 ||
+		 IS_I945G(dev_priv) || IS_I945GM(dev_priv) ||
+		 IS_G33(dev_priv) || IS_PINEVIEW(dev_priv))
+		ggtt->num_fence_regs = 16;
+	else
+		ggtt->num_fence_regs = 8;
+
+	if (intel_vgpu_active(dev_priv))
+		ggtt->num_fence_regs = I915_READ(vgtif_reg(avail_rs.fence_num));
+
+	ggtt->fence_regs = kcalloc(ggtt->num_fence_regs,
+				   sizeof(*ggtt->fence_regs),
+				   GFP_KERNEL);
+	if (!ggtt->fence_regs)
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&ggtt->fence_list);
+
+	/* Initialize fence registers to zero */
+	for (i = 0; i < ggtt->num_fence_regs; i++) {
+		struct drm_i915_fence_reg *fence = &ggtt->fence_regs[i];
+
+		fence->ggtt = ggtt;
+		fence->id = i;
+		list_add_tail(&fence->link, &ggtt->fence_list);
+	}
+	i915_gem_restore_fences(dev_priv);
+
+	i915_gem_detect_bit_6_swizzle(dev_priv);
+	return 0;
+}
+
+static void i915_ggtt_cleanup_fences(struct i915_ggtt *ggtt)
+{
+	kfree(ggtt->fence_regs);
+}
+
 int i915_gem_init_ggtt(struct drm_i915_private *dev_priv)
 {
 	/* Let GEM Manage all of the aperture.
@@ -3012,6 +3058,8 @@ void i915_ggtt_cleanup_hw(struct drm_i915_private *dev_priv)
 
 	mutex_unlock(&dev_priv->drm.struct_mutex);
 
+	i915_ggtt_cleanup_fences(ggtt);
+
 	arch_phys_wc_del(ggtt->mtrr);
 	io_mapping_fini(&ggtt->iomap);
 
@@ -3623,13 +3671,15 @@ int i915_ggtt_init_hw(struct drm_i915_private *dev_priv)
 		ggtt->vm.mm.color_adjust = i915_gtt_color_adjust;
 	mutex_unlock(&dev_priv->drm.struct_mutex);
 
-	i915_ggtt_init_fences(ggtt);
+	ret = i915_ggtt_init_fences(ggtt);
+	if (ret)
+		goto err_fini;
 
 	if (!io_mapping_init_wc(&ggtt->iomap,
 				ggtt->gmadr.start,
 				ggtt->mappable_end)) {
 		ret = -EIO;
-		goto out_gtt_cleanup;
+		goto err_fences;
 	}
 
 	ggtt->mtrr = arch_phys_wc_add(ggtt->gmadr.start, ggtt->mappable_end);
@@ -3640,12 +3690,18 @@ int i915_ggtt_init_hw(struct drm_i915_private *dev_priv)
 	 */
 	ret = i915_gem_init_stolen(dev_priv);
 	if (ret)
-		goto out_gtt_cleanup;
+		goto err_io;
 
 	return 0;
 
-out_gtt_cleanup:
+err_io:
+	arch_phys_wc_del(ggtt->mtrr);
+	io_mapping_fini(&ggtt->iomap);
+err_fences:
+	i915_ggtt_cleanup_fences(ggtt);
+err_fini:
 	ggtt->vm.cleanup(&ggtt->vm);
+	i915_address_space_fini(&ggtt->vm);
 	return ret;
 }
 
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h
index 6bb0b5ec0391..d513a6c5b460 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.h
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.h
@@ -38,7 +38,6 @@
 #include <linux/mm.h>
 #include <linux/pagevec.h>
 
-#include "i915_gem_fence_reg.h"
 #include "i915_request.h"
 #include "i915_selftest.h"
 #include "i915_timeline.h"
@@ -384,7 +383,7 @@ struct i915_ggtt {
 
 	/** LRU list of objects with fence regs on them. */
 	struct list_head fence_list;
-	struct drm_i915_fence_reg fence_regs[I915_MAX_NUM_FENCES];
+	struct drm_i915_fence_reg *fence_regs;
 	int num_fence_regs;
 
 	struct drm_mm_node error_capture;
diff --git a/drivers/gpu/drm/i915/i915_vma.h b/drivers/gpu/drm/i915/i915_vma.h
index 925af79cc6d6..7df156e1ca06 100644
--- a/drivers/gpu/drm/i915/i915_vma.h
+++ b/drivers/gpu/drm/i915/i915_vma.h
@@ -30,6 +30,7 @@
 
 #include <drm/drm_mm.h>
 
+#include "i915_gem_fence_reg.h"
 #include "i915_gem_gtt.h"
 #include "i915_gem_object.h"
 
-- 
2.18.0



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