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drm/i915: Add interface to reserve fence registers for vGPU

PATCH Superseded [email protected] 3 participants 10 messages Aug 30, 2017 – Sep 4, 2017

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PATCH 1/1 drm/i915: Add interface to reserve fence registers for vGPU

From: Changbin Du <[email protected]>

In the past, vGPU alloc fence registers by walking through mm.fence_list to find fence which pin_count = 0 and vma is empty. vGPU may not find enough fence registers this way. Because a fence can be bind to vma even though it is not in using. We have found such failure many times these days.

An option to resolve this issue is that we can force-remove fence from vma in this case.

This patch added two new api to the fence management code:
- i915_reserve_one_fence() will try to find a free fence from fence_list and force-remove vma if need.
- i915_giveback_reserved_fence() reclaim a reserved fence after vGPU has finished.

With this change, the fence management is more clear to work with vGPU. GVTg do not need remove fence from fence_list in private.

---
 drivers/gpu/drm/i915/gvt/aperture_gm.c    | 26 +++++++++------------
 drivers/gpu/drm/i915/i915_drv.h           |  3 +++
 drivers/gpu/drm/i915/i915_gem_fence_reg.c | 39 +++++++++++++++++++++++++++++++
 3 files changed, 53 insertions(+), 15 deletions(-)
drivers/gpu/drm/i915/gvt/aperture_gm.c +11 -15
index ca3d192..29f1bf7 100644
@@ -173,8 +173,8 @@ static void free_vgpu_fence(struct intel_vgpu *vgpu)
 	_clear_vgpu_fence(vgpu);
 	for (i = 0; i < vgpu_fence_sz(vgpu); i++) {
 		reg = vgpu->fence.regs[i];
-		list_add_tail(&reg->link,
-			      &dev_priv->mm.fence_list);
+		i915_giveback_reserved_fence(reg);
+		vgpu->fence.regs[i] = NULL;
 	}
 	mutex_unlock(&dev_priv->drm.struct_mutex);
 
@@ -187,24 +187,19 @@ static int alloc_vgpu_fence(struct intel_vgpu *vgpu)
 	struct drm_i915_private *dev_priv = gvt->dev_priv;
 	struct drm_i915_fence_reg *reg;
 	int i;
-	struct list_head *pos, *q;
 
 	intel_runtime_pm_get(dev_priv);
 
 	/* Request fences from host */
 	mutex_lock(&dev_priv->drm.struct_mutex);
-	i = 0;
-	list_for_each_safe(pos, q, &dev_priv->mm.fence_list) {
-		reg = list_entry(pos, struct drm_i915_fence_reg, link);
-		if (reg->pin_count || reg->vma)
-			continue;
-		list_del(pos);
+
+	for (i = 0; i < vgpu_fence_sz(vgpu); i++) {
+		reg = i915_reserve_one_fence(dev_priv);
+		if (IS_ERR(reg))
+			goto out_free_fence;
+
 		vgpu->fence.regs[i] = reg;
-		if (++i == vgpu_fence_sz(vgpu))
-			break;
 	}
-	if (i != vgpu_fence_sz(vgpu))
-		goto out_free_fence;
 
 	_clear_vgpu_fence(vgpu);
 
@@ -212,13 +207,14 @@ static int alloc_vgpu_fence(struct intel_vgpu *vgpu)
 	intel_runtime_pm_put(dev_priv);
 	return 0;
 out_free_fence:
+	gvt_vgpu_err("Failed to alloc fences\n");
 	/* Return fences to host, if fail */
 	for (i = 0; i < vgpu_fence_sz(vgpu); i++) {
 		reg = vgpu->fence.regs[i];
 		if (!reg)
 			continue;
-		list_add_tail(&reg->link,
-			      &dev_priv->mm.fence_list);
+		i915_giveback_reserved_fence(reg);
+		vgpu->fence.regs[i] = NULL;
 	}
 	mutex_unlock(&dev_priv->drm.struct_mutex);
 	intel_runtime_pm_put(dev_priv);
drivers/gpu/drm/i915/i915_drv.h +3 -0
index 7587ef5..c505b44 100644
@@ -3650,6 +3650,9 @@ i915_vm_to_ppgtt(struct i915_address_space *vm)
 /* i915_gem_fence_reg.c */
 int __must_check i915_vma_get_fence(struct i915_vma *vma);
 int __must_check i915_vma_put_fence(struct i915_vma *vma);
+struct drm_i915_fence_reg *
+i915_reserve_one_fence(struct drm_i915_private *dev_priv);
+void i915_giveback_reserved_fence(struct drm_i915_fence_reg *fence);
 
 void i915_gem_revoke_fences(struct drm_i915_private *dev_priv);
 void i915_gem_restore_fences(struct drm_i915_private *dev_priv);
drivers/gpu/drm/i915/i915_gem_fence_reg.c +39 -0
index 5fe2cd8..63e4e94 100644
@@ -360,6 +360,45 @@ i915_vma_get_fence(struct i915_vma *vma)
 }
 
 /**
+ * i915_reserve_one_fence - Reserve a fence for vGPU
+ * @dev_priv: i915 device private
+ *
+ * This function walks the fence regs looking for a free one and remove
+ * it from the fence_list. It is used to reserve fence for vGPU to use.
+ */
+struct drm_i915_fence_reg *
+i915_reserve_one_fence(struct drm_i915_private *dev_priv)
+{
+	struct drm_i915_fence_reg *fence;
+	int ret;
+
+	fence = fence_find(dev_priv);
+	if (IS_ERR(fence))
+		return fence;
+
+	if (fence->vma) {
+		/* Force-remove fence from VMA */
+		ret = fence_update(fence, NULL);
+		if (ret)
+			return ERR_PTR(ret);
+	}
+
+	list_del(&fence->link);
+	return fence;
+}
+
+/**
+ * i915_giveback_reserved_fence - Reclaim a reserved fence
+ * @fence: the fence reg
+ *
+ * This function add a reserved fence register from vGPU to the fence_list.
+ */
+void i915_giveback_reserved_fence(struct drm_i915_fence_reg *fence)
+{
+	list_add_tail(&fence->link, &fence->i915->mm.fence_list);
+}
+
+/**
  * i915_gem_revoke_fences - revoke fence state
  * @dev_priv: i915 device private
  *
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#1 lore raw

✓ Fi.CI.BAT: success for drm/i915: Add interface to reserve fence registers for vGPU

== Series Details ==

== Series Details ==

Series: drm/i915: Add interface to reserve fence registers for vGPU
URL : https://patchwork.freedesktop.org/series/29523/
State : success

== Summary ==

Series 29523v1 drm/i915: Add interface to reserve fence registers for vGPU
https://patchwork.freedesktop.org/api/1.0/series/29523/revisions/1/mbox/

Test kms_flip:

        Subgroup basic-flip-vs-modeset:
                pass       -> SKIP       (fi-skl-x1585l) fdo#101781

fdo#101781 https://bugs.freedesktop.org/show_bug.cgi?id=101781

fi-bdw-5557u     total:279  pass:268  dwarn:0   dfail:0   fail:0   skip:11  time:457s
fi-bdw-gvtdvm    total:279  pass:265  dwarn:0   dfail:0   fail:0   skip:14  time:440s
fi-blb-e6850     total:279  pass:224  dwarn:1   dfail:0   fail:0   skip:54  time:359s
fi-bsw-n3050     total:279  pass:243  dwarn:0   dfail:0   fail:0   skip:36  time:542s
fi-bwr-2160      total:279  pass:184  dwarn:0   dfail:0   fail:0   skip:95  time:257s
fi-bxt-j4205     total:279  pass:260  dwarn:0   dfail:0   fail:0   skip:19  time:523s
fi-byt-j1900     total:279  pass:254  dwarn:1   dfail:0   fail:0   skip:24  time:522s
fi-byt-n2820     total:279  pass:250  dwarn:1   dfail:0   fail:0   skip:28  time:515s
fi-elk-e7500     total:279  pass:230  dwarn:0   dfail:0   fail:0   skip:49  time:437s
fi-glk-2a        total:279  pass:260  dwarn:0   dfail:0   fail:0   skip:19  time:613s
fi-hsw-4770      total:279  pass:263  dwarn:0   dfail:0   fail:0   skip:16  time:447s
fi-hsw-4770r     total:279  pass:263  dwarn:0   dfail:0   fail:0   skip:16  time:425s
fi-ilk-650       total:279  pass:229  dwarn:0   dfail:0   fail:0   skip:50  time:428s
fi-ivb-3520m     total:279  pass:261  dwarn:0   dfail:0   fail:0   skip:18  time:499s
fi-ivb-3770      total:279  pass:261  dwarn:0   dfail:0   fail:0   skip:18  time:483s
fi-kbl-7500u     total:279  pass:261  dwarn:0   dfail:0   fail:0   skip:18  time:479s
fi-kbl-7560u     total:279  pass:269  dwarn:0   dfail:0   fail:0   skip:10  time:593s
fi-kbl-r         total:279  pass:261  dwarn:0   dfail:0   fail:0   skip:18  time:596s
fi-pnv-d510      total:279  pass:223  dwarn:1   dfail:0   fail:0   skip:55  time:523s
fi-skl-6260u     total:279  pass:269  dwarn:0   dfail:0   fail:0   skip:10  time:463s
fi-skl-6770hq    total:279  pass:269  dwarn:0   dfail:0   fail:0   skip:10  time:492s
fi-skl-gvtdvm    total:279  pass:266  dwarn:0   dfail:0   fail:0   skip:13  time:440s
fi-skl-x1585l    total:279  pass:268  dwarn:0   dfail:0   fail:0   skip:11  time:479s
fi-snb-2520m     total:279  pass:251  dwarn:0   dfail:0   fail:0   skip:28  time:544s
fi-snb-2600      total:279  pass:249  dwarn:0   dfail:0   fail:1   skip:29  time:401s

fi-skl-6700k failed to connect after reboot

6a305b78140aedc9008bdb7e78e70417a8413bbf drm-tip: 2017y-08m-30d-08h-12m-34s UTC integration manifest 26b12b402e67 drm/i915: Add interface to reserve fence registers for vGPU

== Logs ==

For more details see: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_5535/
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#2 lore raw
In reply to [email protected]

Quoting [email protected] (2017-08-30 09:54:21)

Quoted 5 lines

This patch added two new api to the fence management code:
- i915_reserve_one_fence() will try to find a free fence from fence_list and force-remove vma if need.
- i915_giveback_reserved_fence() reclaim a reserved fence after vGPU has finished.

Symmetry: reserve_fence, unreserve_fence.

We need a safeguard here so that the host is able to always able allocate to allocate a fence for the display engine. (That requirement should be quite soft for modern hw, nevertheless it should be in the design to prevent overuse from leading to an unusable system.)
-Chris
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#3 lore raw

Hi chris,

Quoted 9 lines · Chris Wilson

Quoting [email protected] (2017-08-30 09:54:21)

Quoted 5 lines

This patch added two new api to the fence management code:
- i915_reserve_one_fence() will try to find a free fence from fence_list and force-remove vma if need.
- i915_giveback_reserved_fence() reclaim a reserved fence after vGPU has finished.

Symmetry: reserve_fence, unreserve_fence.

ok, I will rename the functions.

Quoted 5 lines

We need a safeguard here so that the host is able to always able allocate to allocate a fence for the display engine. (That requirement should be quite soft for modern hw, nevertheless it should be in the design to prevent overuse from leading to an unusable system.)
-Chris

Yes, agree. Is there any other components always need a fence ready? otherwise, I will add a safeguard to ensure at least 1 fence register remained for host.

Signature · 2 lines
Thanks,
Changbin Du

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#4 lore raw

✗ Fi.CI.IGT: failure for drm/i915: Add interface to reserve fence registers for vGPU

In reply to [email protected]
== Series Details ==

== Series Details ==

Series: drm/i915: Add interface to reserve fence registers for vGPU
URL : https://patchwork.freedesktop.org/series/29523/
State : failure

== Summary ==

Test kms_atomic_transition:

        Subgroup plane-all-transition-fencing:
                skip       -> PASS       (shard-hsw)
Test kms_properties:
        Subgroup plane-properties-legacy:
                skip       -> PASS       (shard-hsw)
Test kms_plane:
        Subgroup plane-position-hole-dpms-pipe-C-planes:
                skip       -> PASS       (shard-hsw)
        Subgroup plane-panning-bottom-right-suspend-pipe-B-planes:
                pass       -> SKIP       (shard-hsw)
Test kms_plane_multiple:
        Subgroup legacy-pipe-E-tiling-y:
                incomplete -> SKIP       (shard-hsw)
Test kms_flip:
        Subgroup flip-vs-expired-vblank-interruptible:
                pass       -> FAIL       (shard-hsw)
        Subgroup plain-flip-fb-recreate-interruptible:
                fail       -> PASS       (shard-hsw)

shard-hsw total:2230 pass:1228 dwarn:0 dfail:0 fail:19 skip:983 time:9597s

== Logs ==

For more details see: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_5535/shards.html
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#5 lore raw

PATCH v2 1/1 drm/i915: Add interface to reserve fence registers for vGPU

In reply to [email protected]

From: Changbin Du <[email protected]>

In the past, vGPU alloc fence registers by walking through mm.fence_list to find fence which pin_count = 0 and vma is empty. vGPU may not find enough fence registers this way. Because a fence can be bind to vma even though it is not in using. We have found such failure many times these days.

An option to resolve this issue is that we can force-remove fence from vma in this case.

This patch added two new api to the fence management code:
- i915_reserve_fence() will try to find a free fence from fence_list and force-remove vma if need.
- i915_unreserve_fence() reclaim a reserved fence after vGPU has finished.

With this change, the fence management is more clear to work with vGPU. GVTg do not need remove fence from fence_list in private.

v2: (Chris)
- Rename the new api for symmetry.
- Add safeguard to ensure at least 1 fence remained for host display.

---
 drivers/gpu/drm/i915/gvt/aperture_gm.c    | 26 ++++++++----------
 drivers/gpu/drm/i915/i915_drv.h           |  3 +++
 drivers/gpu/drm/i915/i915_gem_fence_reg.c | 44 +++++++++++++++++++++++++++++++
 3 files changed, 58 insertions(+), 15 deletions(-)
drivers/gpu/drm/i915/gvt/aperture_gm.c +11 -15
index ca3d192..7c9ec4f 100644
@@ -173,8 +173,8 @@ static void free_vgpu_fence(struct intel_vgpu *vgpu)
 	_clear_vgpu_fence(vgpu);
 	for (i = 0; i < vgpu_fence_sz(vgpu); i++) {
 		reg = vgpu->fence.regs[i];
-		list_add_tail(&reg->link,
-			      &dev_priv->mm.fence_list);
+		i915_unreserve_fence(reg);
+		vgpu->fence.regs[i] = NULL;
 	}
 	mutex_unlock(&dev_priv->drm.struct_mutex);
 
@@ -187,24 +187,19 @@ static int alloc_vgpu_fence(struct intel_vgpu *vgpu)
 	struct drm_i915_private *dev_priv = gvt->dev_priv;
 	struct drm_i915_fence_reg *reg;
 	int i;
-	struct list_head *pos, *q;
 
 	intel_runtime_pm_get(dev_priv);
 
 	/* Request fences from host */
 	mutex_lock(&dev_priv->drm.struct_mutex);
-	i = 0;
-	list_for_each_safe(pos, q, &dev_priv->mm.fence_list) {
-		reg = list_entry(pos, struct drm_i915_fence_reg, link);
-		if (reg->pin_count || reg->vma)
-			continue;
-		list_del(pos);
+
+	for (i = 0; i < vgpu_fence_sz(vgpu); i++) {
+		reg = i915_reserve_fence(dev_priv);
+		if (IS_ERR(reg))
+			goto out_free_fence;
+
 		vgpu->fence.regs[i] = reg;
-		if (++i == vgpu_fence_sz(vgpu))
-			break;
 	}
-	if (i != vgpu_fence_sz(vgpu))
-		goto out_free_fence;
 
 	_clear_vgpu_fence(vgpu);
 
@@ -212,13 +207,14 @@ static int alloc_vgpu_fence(struct intel_vgpu *vgpu)
 	intel_runtime_pm_put(dev_priv);
 	return 0;
 out_free_fence:
+	gvt_vgpu_err("Failed to alloc fences\n");
 	/* Return fences to host, if fail */
 	for (i = 0; i < vgpu_fence_sz(vgpu); i++) {
 		reg = vgpu->fence.regs[i];
 		if (!reg)
 			continue;
-		list_add_tail(&reg->link,
-			      &dev_priv->mm.fence_list);
+		i915_unreserve_fence(reg);
+		vgpu->fence.regs[i] = NULL;
 	}
 	mutex_unlock(&dev_priv->drm.struct_mutex);
 	intel_runtime_pm_put(dev_priv);
drivers/gpu/drm/i915/i915_drv.h +3 -0
index 7587ef5..763a720 100644
@@ -3650,6 +3650,9 @@ i915_vm_to_ppgtt(struct i915_address_space *vm)
 /* i915_gem_fence_reg.c */
 int __must_check i915_vma_get_fence(struct i915_vma *vma);
 int __must_check i915_vma_put_fence(struct i915_vma *vma);
+struct drm_i915_fence_reg *
+i915_reserve_fence(struct drm_i915_private *dev_priv);
+void i915_unreserve_fence(struct drm_i915_fence_reg *fence);
 
 void i915_gem_revoke_fences(struct drm_i915_private *dev_priv);
 void i915_gem_restore_fences(struct drm_i915_private *dev_priv);
drivers/gpu/drm/i915/i915_gem_fence_reg.c +44 -0

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Reviewed-by on v2 1/1
#6 lore raw

Quoting [email protected] (2017-09-01 08:08:26)

Quoted 9 lines
drivers/gpu/drm/i915/i915_gem_fence_reg.c +1 -0
index 5fe2cd8..429ce5f 100644
@@ -360,6 +360,50 @@ i915_vma_get_fence(struct i915_vma *vma)
 }
 
 /**
+ * i915_reserve_fence - Reserve a fence for vGPU

drivers/gpu/drm/i915/i915_gem_fence_reg.c i915_vma_get_fence(struct i915_vma *vma) · line 373

Quoted 10 lines
drivers/gpu/drm/i915/i915_gem_fence_reg.c +10 -0
+ * @dev_priv: i915 device private
+ *
+ * This function walks the fence regs looking for a free one and remove
+ * it from the fence_list. It is used to reserve fence for vGPU to use.
+ */
+struct drm_i915_fence_reg *
+i915_reserve_fence(struct drm_i915_private *dev_priv)
+{
+       struct drm_i915_fence_reg *fence;
+       int ret;

lockdep_assert_held(&dev_priv->drm.struct_mutex);

A reminder for when we move fences to a seperate mutex.

drivers/gpu/drm/i915/i915_gem_fence_reg.c i915_vma_get_fence(struct i915_vma *vma) · line 378

Quoted 5 lines
drivers/gpu/drm/i915/i915_gem_fence_reg.c +5 -0
+
+       /* Host at least need one fence available for display engine. */
+       if (unlikely(dev_priv->mm.fence_list.prev ==
+                    dev_priv->mm.fence_list.next))
+               return ERR_PTR(-ENOSPC);

I would prefer one free fence.

int count;

/* Keep at least one fence available for the display engine */ count = 0;
list_for_each_entry(fence, &dev_priv->mm.fence_list, link)

	count += !fence->pin_count;
if (count <= 1)
	return ERR_PTR(-ENOSPC);
Quoted 14 lines
drivers/gpu/drm/i915/i915_gem_fence_reg.c +14 -0
+
+       fence = fence_find(dev_priv);
+       if (IS_ERR(fence))
+               return fence;
+
+       if (fence->vma) {
+               /* Force-remove fence from VMA */
+               ret = fence_update(fence, NULL);
+               if (ret)
+                       return ERR_PTR(ret);
+       }
+
+       list_del(&fence->link);
+       return fence;

drivers/gpu/drm/i915/i915_gem_fence_reg.c i915_vma_get_fence(struct i915_vma *vma) · line 402

Quoted 10 lines
drivers/gpu/drm/i915/i915_gem_fence_reg.c +10 -0
+}
+
+/**
+ * i915_unreserve_fence - Reclaim a reserved fence
+ * @fence: the fence reg
+ *
+ * This function add a reserved fence register from vGPU to the fence_list.
+ */
+void i915_unreserve_fence(struct drm_i915_fence_reg *fence)
+{

lockdep_assert_held(&dev_priv->drm.struct_mutex);

If you agree to "one free fence",

Otherwise, we need to look carefully at what happens when the search fails. And that may suggest we need to keep one free per crtc, or that we can survive without (but that usually means giving up on fbc and whatnot, thinking of fbc is why I want to keep one spare).

(Time to write some unittests for find-a-fence.)
-Chris
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#7 lore raw
Quoted 23 lines · Chris Wilson

Quoting [email protected] (2017-09-01 08:08:26)

Quoted 9 lines
drivers/gpu/drm/i915/i915_gem_fence_reg.c +1 -0
index 5fe2cd8..429ce5f 100644
@@ -360,6 +360,50 @@ i915_vma_get_fence(struct i915_vma *vma)
 }
 
 /**
+ * i915_reserve_fence - Reserve a fence for vGPU

drivers/gpu/drm/i915/i915_gem_fence_reg.c i915_vma_get_fence(struct i915_vma *vma) · line 373

Quoted 10 lines
drivers/gpu/drm/i915/i915_gem_fence_reg.c +10 -0
+ * @dev_priv: i915 device private
+ *
+ * This function walks the fence regs looking for a free one and remove
+ * it from the fence_list. It is used to reserve fence for vGPU to use.
+ */
+struct drm_i915_fence_reg *
+i915_reserve_fence(struct drm_i915_private *dev_priv)
+{
+       struct drm_i915_fence_reg *fence;
+       int ret;

lockdep_assert_held(&dev_priv->drm.struct_mutex);

Quoted 2 lines

A reminder for when we move fences to a seperate mutex.

ok.

Quoted 8 lines

drivers/gpu/drm/i915/i915_gem_fence_reg.c i915_vma_get_fence(struct i915_vma *vma) · line 378

Quoted 5 lines
drivers/gpu/drm/i915/i915_gem_fence_reg.c +5 -0
+
+       /* Host at least need one fence available for display engine. */
+       if (unlikely(dev_priv->mm.fence_list.prev ==
+                    dev_priv->mm.fence_list.next))
+               return ERR_PTR(-ENOSPC);

I would prefer one free fence.

Quoted 9 lines

int count;

/* Keep at least one fence available for the display engine */ count = 0;
list_for_each_entry(fence, &dev_priv->mm.fence_list, link)

	count += !fence->pin_count;
if (count <= 1)
	return ERR_PTR(-ENOSPC);

Got your idea, will update.

Quoted 31 lines
Quoted 14 lines
drivers/gpu/drm/i915/i915_gem_fence_reg.c +14 -0
+
+       fence = fence_find(dev_priv);
+       if (IS_ERR(fence))
+               return fence;
+
+       if (fence->vma) {
+               /* Force-remove fence from VMA */
+               ret = fence_update(fence, NULL);
+               if (ret)
+                       return ERR_PTR(ret);
+       }
+
+       list_del(&fence->link);
+       return fence;

drivers/gpu/drm/i915/i915_gem_fence_reg.c i915_vma_get_fence(struct i915_vma *vma) · line 402

Quoted 10 lines
drivers/gpu/drm/i915/i915_gem_fence_reg.c +10 -0
+}
+
+/**
+ * i915_unreserve_fence - Reclaim a reserved fence
+ * @fence: the fence reg
+ *
+ * This function add a reserved fence register from vGPU to the fence_list.
+ */
+void i915_unreserve_fence(struct drm_i915_fence_reg *fence)
+{

lockdep_assert_held(&dev_priv->drm.struct_mutex);

If you agree to "one free fence",

Quoted 7 lines

Otherwise, we need to look carefully at what happens when the search fails. And that may suggest we need to keep one free per crtc, or that we can survive without (but that usually means giving up on fbc and whatnot, thinking of fbc is why I want to keep one spare).

(Time to write some unittests for find-a-fence.)
-Chris

I agree to "one free fence", which is simpler. Currently GVTg will at most use 4x7=28 fence registers (4 per VM, and up to 7 VMs), so at least 4 will remained for host. I agree to your concern, it is significative.

Signature · 2 lines
Thanks,
Changbin Du

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#8 lore raw

✓ Fi.CI.BAT: success for drm/i915: Add interface to reserve fence registers for vGPU (rev2)

In reply to [email protected]
== Series Details ==

== Series Details ==

Series: drm/i915: Add interface to reserve fence registers for vGPU (rev2)
URL : https://patchwork.freedesktop.org/series/29523/
State : success

== Summary ==

Series 29523v2 drm/i915: Add interface to reserve fence registers for vGPU
https://patchwork.freedesktop.org/api/1.0/series/29523/revisions/2/mbox/

Test gem_exec_flush:

        Subgroup basic-batch-kernel-default-uc:
                pass       -> FAIL       (fi-snb-2600) fdo#100007
Test kms_cursor_legacy:
        Subgroup basic-busy-flip-before-cursor-legacy:
                fail       -> PASS       (fi-snb-2600) fdo#100215
        Subgroup basic-flip-after-cursor-varying-size:
                fail       -> PASS       (fi-hsw-4770) fdo#102402 +1

fdo#100007 https://bugs.freedesktop.org/show_bug.cgi?id=100007
fdo#100215 https://bugs.freedesktop.org/show_bug.cgi?id=100215
fdo#102402 https://bugs.freedesktop.org/show_bug.cgi?id=102402

fi-bdw-5557u     total:288  pass:268  dwarn:0   dfail:0   fail:0   skip:20  time:457s
fi-bdw-gvtdvm    total:288  pass:265  dwarn:0   dfail:0   fail:0   skip:23  time:449s
fi-blb-e6850     total:288  pass:224  dwarn:1   dfail:0   fail:0   skip:63  time:360s
fi-bsw-n3050     total:288  pass:243  dwarn:0   dfail:0   fail:0   skip:45  time:563s
fi-bwr-2160      total:288  pass:184  dwarn:0   dfail:0   fail:0   skip:104 time:255s
fi-bxt-j4205     total:288  pass:260  dwarn:0   dfail:0   fail:0   skip:28  time:525s
fi-byt-j1900     total:288  pass:254  dwarn:1   dfail:0   fail:0   skip:33  time:518s
fi-byt-n2820     total:288  pass:250  dwarn:1   dfail:0   fail:0   skip:37  time:519s
fi-elk-e7500     total:288  pass:230  dwarn:0   dfail:0   fail:0   skip:58  time:437s
fi-glk-2a        total:288  pass:260  dwarn:0   dfail:0   fail:0   skip:28  time:610s
fi-hsw-4770      total:288  pass:263  dwarn:0   dfail:0   fail:0   skip:25  time:443s
fi-hsw-4770r     total:288  pass:263  dwarn:0   dfail:0   fail:0   skip:25  time:425s
fi-ilk-650       total:288  pass:229  dwarn:0   dfail:0   fail:0   skip:59  time:428s
fi-ivb-3520m     total:288  pass:261  dwarn:0   dfail:0   fail:0   skip:27  time:508s
fi-ivb-3770      total:288  pass:261  dwarn:0   dfail:0   fail:0   skip:27  time:478s
fi-kbl-7500u     total:288  pass:264  dwarn:1   dfail:0   fail:0   skip:23  time:517s
fi-kbl-7560u     total:288  pass:269  dwarn:0   dfail:0   fail:0   skip:19  time:604s
fi-kbl-r         total:288  pass:261  dwarn:0   dfail:0   fail:0   skip:27  time:596s
fi-pnv-d510      total:288  pass:223  dwarn:1   dfail:0   fail:0   skip:64  time:529s
fi-skl-6260u     total:288  pass:269  dwarn:0   dfail:0   fail:0   skip:19  time:468s
fi-skl-6700k     total:288  pass:265  dwarn:0   dfail:0   fail:0   skip:23  time:531s
fi-skl-6770hq    total:288  pass:269  dwarn:0   dfail:0   fail:0   skip:19  time:487s
fi-skl-gvtdvm    total:288  pass:266  dwarn:0   dfail:0   fail:0   skip:22  time:440s
fi-skl-x1585l    total:288  pass:268  dwarn:0   dfail:0   fail:0   skip:20  time:501s
fi-snb-2520m     total:288  pass:251  dwarn:0   dfail:0   fail:0   skip:37  time:549s
fi-snb-2600      total:288  pass:249  dwarn:0   dfail:0   fail:1   skip:38  time:407s

ccf4ca2d93383fe1a234aba83df9c21400216433 drm-tip: 2017y-08m-31d-18h-37m-46s UTC integration manifest f108c11aabb5 drm/i915: Add interface to reserve fence registers for vGPU

== Logs ==

For more details see: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_5557/
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#9 lore raw

✗ Fi.CI.IGT: warning for drm/i915: Add interface to reserve fence registers for vGPU (rev2)

In reply to [email protected]
== Series Details ==

== Series Details ==

Series: drm/i915: Add interface to reserve fence registers for vGPU (rev2)
URL : https://patchwork.freedesktop.org/series/29523/
State : warning

== Summary ==

Test kms_vblank:

        Subgroup wait-busy:
                pass       -> SKIP       (shard-hsw)

shard-hsw total:2265 pass:1231 dwarn:0 dfail:0 fail:17 skip:1017 time:9611s

== Logs ==

For more details see: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_5557/shards.html
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