1 files changed, 13 insertions, 29 deletions

diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
index f6c78c0fa74b..c88e538b2ef4 100644
--- a/drivers/gpu/drm/i915/i915_request.c
+++ b/drivers/gpu/drm/i915/i915_request.c
@@ -502,15 +502,6 @@ void __i915_request_unsubmit(struct i915_request *request)
         /* We may be recursing from the signal callback of another i915 fence */
         spin_lock_nested(&request->lock, SINGLE_DEPTH_NESTING);
 
-        /*
-         * As we do not allow WAIT to preempt inflight requests,
-         * once we have executed a request, along with triggering
-         * any execution callbacks, we must preserve its ordering
-         * within the non-preemptible FIFO.
-         */
-        BUILD_BUG_ON(__NO_PREEMPTION & ~I915_PRIORITY_MASK); /* only internal */
-        request->sched.attr.priority |= __NO_PREEMPTION;
-
         if (test_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT, &request->fence.flags))
                 i915_request_cancel_breadcrumb(request);
 
@@ -582,18 +573,7 @@ semaphore_notify(struct i915_sw_fence *fence, enum i915_sw_fence_notify state)
 
         switch (state) {
         case FENCE_COMPLETE:
-                /*
-                 * We only check a small portion of our dependencies
-                 * and so cannot guarantee that there remains no
-                 * semaphore chain across all. Instead of opting
-                 * for the full NOSEMAPHORE boost, we go for the
-                 * smaller (but still preempting) boost of
-                 * NEWCLIENT. This will be enough to boost over
-                 * a busywaiting request (as that cannot be
-                 * NEWCLIENT) without accidentally boosting
-                 * a busywait over real work elsewhere.
-                 */
-                i915_schedule_bump_priority(request, I915_PRIORITY_NEWCLIENT);
+                i915_schedule_bump_priority(request, I915_PRIORITY_NOSEMAPHORE);
                 break;
 
         case FENCE_FREE:
@@ -874,12 +854,6 @@ emit_semaphore_wait(struct i915_request *to,
         if (err < 0)
                 return err;
 
-        err = i915_sw_fence_await_dma_fence(&to->semaphore,
-                                            &from->fence, 0,
-                                            I915_FENCE_GFP);
-        if (err < 0)
-                return err;
-
         /* We need to pin the signaler's HWSP until we are finished reading. */
         err = i915_timeline_read_hwsp(from, to, &hwsp_offset);
         if (err)
@@ -945,8 +919,18 @@ i915_request_await_request(struct i915_request *to, struct i915_request *from)
                                                     &from->fence, 0,
                                                     I915_FENCE_GFP);
         }
+        if (ret < 0)
+                return ret;
 
-        return ret < 0 ? ret : 0;
+        if (to->sched.flags & I915_SCHED_HAS_SEMAPHORE_CHAIN) {
+                ret = i915_sw_fence_await_dma_fence(&to->semaphore,
+                                                    &from->fence, 0,
+                                                    I915_FENCE_GFP);
+                if (ret < 0)
+                        return ret;
+        }
+
+        return 0;
 }
 
 int
@@ -1237,7 +1221,7 @@ void i915_request_add(struct i915_request *request)
                  * the bulk clients. (FQ_CODEL)
                  */
                 if (list_empty(&request->sched.signalers_list))
-                        attr.priority |= I915_PRIORITY_NEWCLIENT;
+                        attr.priority |= I915_PRIORITY_WAIT;
 
                 engine->schedule(request, &attr);
         }