Merge tag 'gvt-next-2020-04-22' of https://github.com/intel/gvt-linux into drm-intel-next-queued

gvt-next-2020-04-22

- remove non-upstream xen support bits (Christoph)
- guest context shadow copy optimization (Yan)
- guest context tracking for shadow skip optimization (Yan)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
From: Zhenyu Wang <zhenyuw@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200422051230.GH11247@zhen-hp.sh.intel.com

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

@@ -2341,12 +2341,27 @@ int intel_vgpu_emulate_ggtt_mmio_write(struct intel_vgpu *vgpu,
 {
 	const struct intel_gvt_device_info *info = &vgpu->gvt->device_info;
 	int ret;
+	struct intel_vgpu_submission *s = &vgpu->submission;
+	struct intel_engine_cs *engine;
+	int i;
 
 	if (bytes != 4 && bytes != 8)
 		return -EINVAL;
 
 	off -= info->gtt_start_offset;
 	ret = emulate_ggtt_mmio_write(vgpu, off, p_data, bytes);
+
+	/* if ggtt of last submitted context is written,
+	 * that context is probably got unpinned.
+	 * Set last shadowed ctx to invalid.
+	 */
+	for_each_engine(engine, vgpu->gvt->gt, i) {
+		if (!s->last_ctx[i].valid)
+			continue;
+
+		if (s->last_ctx[i].lrca == (off >> info->gtt_entry_size_shift))
+			s->last_ctx[i].valid = false;
+	}
 	return ret;
 }
 

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

@@ -31,7 +31,6 @@
  */
 
 #include <linux/types.h>
-#include <xen/xen.h>
 #include <linux/kthread.h>
 
 #include "i915_drv.h"

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

@@ -163,6 +163,11 @@ struct intel_vgpu_submission {
 	const struct intel_vgpu_submission_ops *ops;
 	int virtual_submission_interface;
 	bool active;
+	struct {
+		u32 lrca;
+		bool valid;
+		u64 ring_context_gpa;
+	} last_ctx[I915_NUM_ENGINES];
 };
 
 struct intel_vgpu {

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

@@ -79,6 +79,4 @@ struct intel_gvt_mpt {
 	bool (*is_valid_gfn)(unsigned long handle, unsigned long gfn);
 };
 
-extern struct intel_gvt_mpt xengt_mpt;
-
 #endif /* _GVT_HYPERCALL_H_ */

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

@@ -128,16 +128,24 @@ static int populate_shadow_context(struct intel_vgpu_workload *workload)
 {
 	struct intel_vgpu *vgpu = workload->vgpu;
 	struct intel_gvt *gvt = vgpu->gvt;
-	struct drm_i915_gem_object *ctx_obj =
-		workload->req->context->state->obj;
+	struct intel_context *ctx = workload->req->context;
 	struct execlist_ring_context *shadow_ring_context;
-	struct page *page;
 	void *dst;
+	void *context_base;
 	unsigned long context_gpa, context_page_num;
+	unsigned long gpa_base; /* first gpa of consecutive GPAs */
+	unsigned long gpa_size; /* size of consecutive GPAs */
+	struct intel_vgpu_submission *s = &vgpu->submission;
 	int i;
+	bool skip = false;
+	int ring_id = workload->engine->id;
 
-	page = i915_gem_object_get_page(ctx_obj, LRC_STATE_PN);
-	shadow_ring_context = kmap(page);
+	GEM_BUG_ON(!intel_context_is_pinned(ctx));
+
+	context_base = (void *) ctx->lrc_reg_state -
+				(LRC_STATE_PN << I915_GTT_PAGE_SHIFT);
+
+	shadow_ring_context = (void *) ctx->lrc_reg_state;
 
 	sr_oa_regs(workload, (u32 *)shadow_ring_context, true);
 #define COPY_REG(name) \
@@ -169,23 +177,43 @@ static int populate_shadow_context(struct intel_vgpu_workload *workload)
 			I915_GTT_PAGE_SIZE - sizeof(*shadow_ring_context));
 
 	sr_oa_regs(workload, (u32 *)shadow_ring_context, false);
-	kunmap(page);
 
-	if (IS_RESTORE_INHIBIT(shadow_ring_context->ctx_ctrl.val))
-		return 0;
+	gvt_dbg_sched("ring %s workload lrca %x, ctx_id %x, ctx gpa %llx",
+			workload->engine->name, workload->ctx_desc.lrca,
+			workload->ctx_desc.context_id,
+			workload->ring_context_gpa);
 
-	gvt_dbg_sched("ring %s workload lrca %x",
-		      workload->engine->name,
-		      workload->ctx_desc.lrca);
+	/* only need to ensure this context is not pinned/unpinned during the
+	 * period from last submission to this this submission.
+	 * Upon reaching this function, the currently submitted context is not
+	 * supposed to get unpinned. If a misbehaving guest driver ever does
+	 * this, it would corrupt itself.
+	 */
+	if (s->last_ctx[ring_id].valid &&
+			(s->last_ctx[ring_id].lrca ==
+				workload->ctx_desc.lrca) &&
+			(s->last_ctx[ring_id].ring_context_gpa ==
+				workload->ring_context_gpa))
+		skip = true;
 
+	s->last_ctx[ring_id].lrca = workload->ctx_desc.lrca;
+	s->last_ctx[ring_id].ring_context_gpa = workload->ring_context_gpa;
+
+	if (IS_RESTORE_INHIBIT(shadow_ring_context->ctx_ctrl.val) || skip)
+		return 0;
+
+	s->last_ctx[ring_id].valid = false;
 	context_page_num = workload->engine->context_size;
 	context_page_num = context_page_num >> PAGE_SHIFT;
 
 	if (IS_BROADWELL(gvt->gt->i915) && workload->engine->id == RCS0)
 		context_page_num = 19;
 
-	i = 2;
-	while (i < context_page_num) {
+	/* find consecutive GPAs from gma until the first inconsecutive GPA.
+	 * read from the continuous GPAs into dst virtual address
+	 */
+	gpa_size = 0;
+	for (i = 2; i < context_page_num; i++) {
 		context_gpa = intel_vgpu_gma_to_gpa(vgpu->gtt.ggtt_mm,
 				(u32)((workload->ctx_desc.lrca + i) <<
 				I915_GTT_PAGE_SHIFT));
@@ -194,13 +222,26 @@ static int populate_shadow_context(struct intel_vgpu_workload *workload)
 			return -EFAULT;
 		}
 
-		page = i915_gem_object_get_page(ctx_obj, i);
-		dst = kmap(page);
-		intel_gvt_hypervisor_read_gpa(vgpu, context_gpa, dst,
-				I915_GTT_PAGE_SIZE);
-		kunmap(page);
-		i++;
+		if (gpa_size == 0) {
+			gpa_base = context_gpa;
+			dst = context_base + (i << I915_GTT_PAGE_SHIFT);
+		} else if (context_gpa != gpa_base + gpa_size)
+			goto read;
+
+		gpa_size += I915_GTT_PAGE_SIZE;
+
+		if (i == context_page_num - 1)
+			goto read;
+
+		continue;
+
+read:
+		intel_gvt_hypervisor_read_gpa(vgpu, gpa_base, dst, gpa_size);
+		gpa_base = context_gpa;
+		gpa_size = I915_GTT_PAGE_SIZE;
+		dst = context_base + (i << I915_GTT_PAGE_SHIFT);
 	}
+	s->last_ctx[ring_id].valid = true;
 	return 0;
 }
 
@@ -783,11 +824,13 @@ static void update_guest_context(struct intel_vgpu_workload *workload)
 {
 	struct i915_request *rq = workload->req;
 	struct intel_vgpu *vgpu = workload->vgpu;
-	struct drm_i915_gem_object *ctx_obj = rq->context->state->obj;
 	struct execlist_ring_context *shadow_ring_context;
-	struct page *page;
+	struct intel_context *ctx = workload->req->context;
+	void *context_base;
 	void *src;
 	unsigned long context_gpa, context_page_num;
+	unsigned long gpa_base; /* first gpa of consecutive GPAs */
+	unsigned long gpa_size; /* size of consecutive GPAs*/
 	int i;
 	u32 ring_base;
 	u32 head, tail;
@@ -796,6 +839,8 @@ static void update_guest_context(struct intel_vgpu_workload *workload)
 	gvt_dbg_sched("ring id %d workload lrca %x\n", rq->engine->id,
 		      workload->ctx_desc.lrca);
 
+	GEM_BUG_ON(!intel_context_is_pinned(ctx));
+
 	head = workload->rb_head;
 	tail = workload->rb_tail;
 	wrap_count = workload->guest_rb_head >> RB_HEAD_WRAP_CNT_OFF;
@@ -819,9 +864,14 @@ static void update_guest_context(struct intel_vgpu_workload *workload)
 	if (IS_BROADWELL(rq->i915) && rq->engine->id == RCS0)
 		context_page_num = 19;
 
-	i = 2;
+	context_base = (void *) ctx->lrc_reg_state -
+			(LRC_STATE_PN << I915_GTT_PAGE_SHIFT);
 
-	while (i < context_page_num) {
+	/* find consecutive GPAs from gma until the first inconsecutive GPA.
+	 * write to the consecutive GPAs from src virtual address
+	 */
+	gpa_size = 0;
+	for (i = 2; i < context_page_num; i++) {
 		context_gpa = intel_vgpu_gma_to_gpa(vgpu->gtt.ggtt_mm,
 				(u32)((workload->ctx_desc.lrca + i) <<
 					I915_GTT_PAGE_SHIFT));
@@ -830,19 +880,30 @@ static void update_guest_context(struct intel_vgpu_workload *workload)
 			return;
 		}
 
-		page = i915_gem_object_get_page(ctx_obj, i);
-		src = kmap(page);
-		intel_gvt_hypervisor_write_gpa(vgpu, context_gpa, src,
-				I915_GTT_PAGE_SIZE);
-		kunmap(page);
-		i++;
+		if (gpa_size == 0) {
+			gpa_base = context_gpa;
+			src = context_base + (i << I915_GTT_PAGE_SHIFT);
+		} else if (context_gpa != gpa_base + gpa_size)
+			goto write;
+
+		gpa_size += I915_GTT_PAGE_SIZE;
+
+		if (i == context_page_num - 1)
+			goto write;
+
+		continue;
+
+write:
+		intel_gvt_hypervisor_write_gpa(vgpu, gpa_base, src, gpa_size);
+		gpa_base = context_gpa;
+		gpa_size = I915_GTT_PAGE_SIZE;
+		src = context_base + (i << I915_GTT_PAGE_SHIFT);
 	}
 
 	intel_gvt_hypervisor_write_gpa(vgpu, workload->ring_context_gpa +
 		RING_CTX_OFF(ring_header.val), &workload->rb_tail, 4);
 
-	page = i915_gem_object_get_page(ctx_obj, LRC_STATE_PN);
-	shadow_ring_context = kmap(page);
+	shadow_ring_context = (void *) ctx->lrc_reg_state;
 
 #define COPY_REG(name) \
 	intel_gvt_hypervisor_write_gpa(vgpu, workload->ring_context_gpa + \
@@ -859,8 +920,6 @@ static void update_guest_context(struct intel_vgpu_workload *workload)
 			(void *)shadow_ring_context +
 			sizeof(*shadow_ring_context),
 			I915_GTT_PAGE_SIZE - sizeof(*shadow_ring_context));
-
-	kunmap(page);
 }
 
 void intel_vgpu_clean_workloads(struct intel_vgpu *vgpu,
@@ -1259,6 +1318,8 @@ int intel_vgpu_setup_submission(struct intel_vgpu *vgpu)
 	atomic_set(&s->running_workload_num, 0);
 	bitmap_zero(s->tlb_handle_pending, I915_NUM_ENGINES);
 
+	memset(s->last_ctx, 0, sizeof(s->last_ctx));
+
 	i915_vm_put(&ppgtt->vm);
 	return 0;