drm/i915/gvt: refactor function intel_vgpu_submit_execlist

The function intel_vgpu_submit_execlist could be more simpler. It
actually does:
  1) validate the submission. The first context must be valid,
     and all two must be privilege_access.
  2) submit valid contexts. The first one need emulate schedule_in.

We do not need a bitmap, valid desc copy valid_desc. Local variable
emulate_schedule_in also can be optimized out.

v2: dump desc content in err msg (Zhi Wang)

Signed-off-by: Changbin Du <changbin.du@intel.com>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

1 files changed, 23 insertions, 33 deletions

diff --git a/drivers/gpu/drm/i915/gvt/execlist.c b/drivers/gpu/drm/i915/gvt/execlist.c
index dca989eb2d42..8bba38fa19b8 100644
--- a/drivers/gpu/drm/i915/gvt/execlist.c
+++ b/drivers/gpu/drm/i915/gvt/execlist.c
@@ -708,53 +708,43 @@ static int submit_context(struct intel_vgpu *vgpu, int ring_id,
 int intel_vgpu_submit_execlist(struct intel_vgpu *vgpu, int ring_id)
 {
         struct intel_vgpu_execlist *execlist = &vgpu->execlist[ring_id];
-        struct execlist_ctx_descriptor_format *desc[2], valid_desc[2];
-        unsigned long valid_desc_bitmap = 0;
-        bool emulate_schedule_in = true;
-        int ret;
-        int i;
+        struct execlist_ctx_descriptor_format desc[2];
+        int i, ret;
 
-        memset(valid_desc, 0, sizeof(valid_desc));
+        desc[0] = *get_desc_from_elsp_dwords(&execlist->elsp_dwords, 1);
+        desc[1] = *get_desc_from_elsp_dwords(&execlist->elsp_dwords, 0);
 
-        desc[0] = get_desc_from_elsp_dwords(&execlist->elsp_dwords, 1);
-        desc[1] = get_desc_from_elsp_dwords(&execlist->elsp_dwords, 0);
+        if (!desc[0].valid) {
+                gvt_vgpu_err("invalid elsp submission, desc0 is invalid\n");
+                goto inv_desc;
+        }
 
-        for (i = 0; i < 2; i++) {
-                if (!desc[i]->valid)
+        for (i = 0; i < ARRAY_SIZE(desc); i++) {
+                if (!desc[i].valid)
                         continue;
-
-                if (!desc[i]->privilege_access) {
+                if (!desc[i].privilege_access) {
                         gvt_vgpu_err("unexpected GGTT elsp submission\n");
-                        return -EINVAL;
+                        goto inv_desc;
                 }
-
-                /* TODO: add another guest context checks here. */
-                set_bit(i, &valid_desc_bitmap);
-                valid_desc[i] = *desc[i];
-        }
-
-        if (!valid_desc_bitmap) {
-                gvt_vgpu_err("no valid desc in a elsp submission\n");
-                return -EINVAL;
-        }
-
-        if (!test_bit(0, (void *)&valid_desc_bitmap) &&
-                        test_bit(1, (void *)&valid_desc_bitmap)) {
-                gvt_vgpu_err("weird elsp submission, desc 0 is not valid\n");
-                return -EINVAL;
         }
 
         /* submit workload */
-        for_each_set_bit(i, (void *)&valid_desc_bitmap, 2) {
-                ret = submit_context(vgpu, ring_id, &valid_desc[i],
-                                emulate_schedule_in);
+        for (i = 0; i < ARRAY_SIZE(desc); i++) {
+                if (!desc[i].valid)
+                        continue;
+                ret = submit_context(vgpu, ring_id, &desc[i], i == 0);
                 if (ret) {
-                        gvt_vgpu_err("fail to schedule workload\n");
+                        gvt_vgpu_err("failed to submit desc %d\n", i);
                         return ret;
                 }
-                emulate_schedule_in = false;
         }
+
         return 0;
+
+inv_desc:
+        gvt_vgpu_err("descriptors content: desc0 %08x %08x desc1 %08x %08x\n",
+                     desc[0].udw, desc[0].ldw, desc[1].udw, desc[1].ldw);
+        return -EINVAL;
 }
 
 static void init_vgpu_execlist(struct intel_vgpu *vgpu, int ring_id)