drm/i915/gvt: define weight according to vGPU type

The weight defines proportional control of physical GPU resource
shared between vGPUs. So far the weight is tied to a specific vGPU
type, i.e when creating multiple vGPUs with different types, they
will inherit different weights.

e.g. The weight of type GVTg_V5_2 is 8, the weight of type GVTg_V5_4
is 4, so vGPU of type GVTg_V5_2 has double vGPU resource of vGPU type
GVTg_V5_4.

TODO: allow user control the weight setting in the future.
Signed-off-by: Ping Gao <ping.a.gao@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

drivers/gpu/drm/i915/gvt/gvt.h

@@ -151,6 +151,7 @@ struct intel_vgpu {
 	bool failsafe;
 	bool resetting;
 	void *sched_data;
+	struct vgpu_sched_ctl sched_ctl;
 
 	struct intel_vgpu_fence fence;
 	struct intel_vgpu_gm gm;
@@ -220,6 +221,7 @@ struct intel_vgpu_type {
 	unsigned int low_gm_size;
 	unsigned int high_gm_size;
 	unsigned int fence;
+	unsigned int weight;
 	enum intel_vgpu_edid resolution;
 };
 
@@ -328,6 +330,8 @@ struct intel_vgpu_creation_params {
 	__u64 resolution;
 	__s32 primary;
 	__u64 vgpu_id;
+
+	__u32 weight;
 };
 
 int intel_vgpu_alloc_resource(struct intel_vgpu *vgpu,

drivers/gpu/drm/i915/gvt/kvmgt.c

@@ -295,10 +295,12 @@ static ssize_t description_show(struct kobject *kobj, struct device *dev,
 		return 0;
 
 	return sprintf(buf, "low_gm_size: %dMB\nhigh_gm_size: %dMB\n"
-		       "fence: %d\nresolution: %s\n",
+		       "fence: %d\nresolution: %s\n"
+		       "weight: %d\n",
 		       BYTES_TO_MB(type->low_gm_size),
 		       BYTES_TO_MB(type->high_gm_size),
-		       type->fence, vgpu_edid_str(type->resolution));
+		       type->fence, vgpu_edid_str(type->resolution),
+		       type->weight);
 }
 
 static MDEV_TYPE_ATTR_RO(available_instances);

drivers/gpu/drm/i915/gvt/sched_policy.c

@@ -237,6 +237,7 @@ static int tbs_sched_init_vgpu(struct intel_vgpu *vgpu)
 	if (!data)
 		return -ENOMEM;
 
+	data->sched_ctl.weight = vgpu->sched_ctl.weight;
 	data->vgpu = vgpu;
 	INIT_LIST_HEAD(&data->lru_list);
 

drivers/gpu/drm/i915/gvt/vgpu.c

@@ -64,18 +64,28 @@ void populate_pvinfo_page(struct intel_vgpu *vgpu)
 	WARN_ON(sizeof(struct vgt_if) != VGT_PVINFO_SIZE);
 }
 
+#define VGPU_MAX_WEIGHT 16
+#define VGPU_WEIGHT(vgpu_num)	\
+	(VGPU_MAX_WEIGHT / (vgpu_num))
+
 static struct {
 	unsigned int low_mm;
 	unsigned int high_mm;
 	unsigned int fence;
+
+	/* A vGPU with a weight of 8 will get twice as much GPU as a vGPU
+	 * with a weight of 4 on a contended host, different vGPU type has
+	 * different weight set. Legal weights range from 1 to 16.
+	 */
+	unsigned int weight;
 	enum intel_vgpu_edid edid;
 	char *name;
 } vgpu_types[] = {
 /* Fixed vGPU type table */
-	{ MB_TO_BYTES(64), MB_TO_BYTES(384), 4, GVT_EDID_1024_768, "8" },
-	{ MB_TO_BYTES(128), MB_TO_BYTES(512), 4, GVT_EDID_1920_1200, "4" },
-	{ MB_TO_BYTES(256), MB_TO_BYTES(1024), 4, GVT_EDID_1920_1200, "2" },
-	{ MB_TO_BYTES(512), MB_TO_BYTES(2048), 4, GVT_EDID_1920_1200, "1" },
+	{ MB_TO_BYTES(64), MB_TO_BYTES(384), 4, VGPU_WEIGHT(8), GVT_EDID_1024_768, "8" },
+	{ MB_TO_BYTES(128), MB_TO_BYTES(512), 4, VGPU_WEIGHT(4), GVT_EDID_1920_1200, "4" },
+	{ MB_TO_BYTES(256), MB_TO_BYTES(1024), 4, VGPU_WEIGHT(2), GVT_EDID_1920_1200, "2" },
+	{ MB_TO_BYTES(512), MB_TO_BYTES(2048), 4, VGPU_WEIGHT(1), GVT_EDID_1920_1200, "1" },
 };
 
 /**
@@ -120,6 +130,12 @@ int intel_gvt_init_vgpu_types(struct intel_gvt *gvt)
 		gvt->types[i].low_gm_size = vgpu_types[i].low_mm;
 		gvt->types[i].high_gm_size = vgpu_types[i].high_mm;
 		gvt->types[i].fence = vgpu_types[i].fence;
+
+		if (vgpu_types[i].weight < 1 ||
+					vgpu_types[i].weight > VGPU_MAX_WEIGHT)
+			return -EINVAL;
+
+		gvt->types[i].weight = vgpu_types[i].weight;
 		gvt->types[i].resolution = vgpu_types[i].edid;
 		gvt->types[i].avail_instance = min(low_avail / vgpu_types[i].low_mm,
 						   high_avail / vgpu_types[i].high_mm);
@@ -131,11 +147,12 @@ int intel_gvt_init_vgpu_types(struct intel_gvt *gvt)
 			sprintf(gvt->types[i].name, "GVTg_V5_%s",
 						vgpu_types[i].name);
 
-		gvt_dbg_core("type[%d]: %s avail %u low %u high %u fence %u res %s\n",
+		gvt_dbg_core("type[%d]: %s avail %u low %u high %u fence %u weight %u res %s\n",
 			     i, gvt->types[i].name,
 			     gvt->types[i].avail_instance,
 			     gvt->types[i].low_gm_size,
 			     gvt->types[i].high_gm_size, gvt->types[i].fence,
+			     gvt->types[i].weight,
 			     vgpu_edid_str(gvt->types[i].resolution));
 	}
 
@@ -239,6 +256,7 @@ static struct intel_vgpu *__intel_gvt_create_vgpu(struct intel_gvt *gvt,
 	vgpu->id = ret;
 	vgpu->handle = param->handle;
 	vgpu->gvt = gvt;
+	vgpu->sched_ctl.weight = param->weight;
 	bitmap_zero(vgpu->tlb_handle_pending, I915_NUM_ENGINES);
 
 	intel_vgpu_init_cfg_space(vgpu, param->primary);
@@ -325,6 +343,7 @@ struct intel_vgpu *intel_gvt_create_vgpu(struct intel_gvt *gvt,
 	param.low_gm_sz = type->low_gm_size;
 	param.high_gm_sz = type->high_gm_size;
 	param.fence_sz = type->fence;
+	param.weight = type->weight;
 	param.resolution = type->resolution;
 
 	/* XXX current param based on MB */