[PATCH 13/17] drm/i915: Dynamically allocate the array of drm_i915_gem_fence_reg

Chris Wilson chris at chris-wilson.co.uk
Mon Jul 23 20:09:51 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 a0381f81318e..29ad4c826a8b 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -5553,39 +5553,6 @@ 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 6e730c9393a5..9ab66a483b01 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"
@@ -2913,6 +2914,51 @@ 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.
@@ -3002,6 +3048,8 @@ 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);
 
@@ -3611,13 +3659,15 @@ 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);
@@ -3628,12 +3678,18 @@ 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 22f08c4c017d..396b8d6205d4 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"
@@ -405,7 +404,7 @@ 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 d6137670f204..58467b034a2f 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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