Merge tag 'drm-fixes-5.4-2019-10-16' of git://people.freedesktop.org/~agd5f/linux...
[linux-2.6-microblaze.git] / drivers / gpu / drm / i915 / gt / intel_lrc.c
index d425844..06a506c 100644 (file)
@@ -234,6 +234,13 @@ static void execlists_init_reg_state(u32 *reg_state,
                                     struct intel_engine_cs *engine,
                                     struct intel_ring *ring);
 
+static void mark_eio(struct i915_request *rq)
+{
+       if (!i915_request_signaled(rq))
+               dma_fence_set_error(&rq->fence, -EIO);
+       i915_request_mark_complete(rq);
+}
+
 static inline u32 intel_hws_preempt_address(struct intel_engine_cs *engine)
 {
        return (i915_ggtt_offset(engine->status_page.vma) +
@@ -631,7 +638,6 @@ execlists_schedule_out(struct i915_request *rq)
        struct intel_engine_cs *cur, *old;
 
        trace_i915_request_out(rq);
-       GEM_BUG_ON(intel_context_inflight(ce) != rq->engine);
 
        old = READ_ONCE(ce->inflight);
        do
@@ -797,6 +803,17 @@ static bool can_merge_rq(const struct i915_request *prev,
        GEM_BUG_ON(prev == next);
        GEM_BUG_ON(!assert_priority_queue(prev, next));
 
+       /*
+        * We do not submit known completed requests. Therefore if the next
+        * request is already completed, we can pretend to merge it in
+        * with the previous context (and we will skip updating the ELSP
+        * and tracking). Thus hopefully keeping the ELSP full with active
+        * contexts, despite the best efforts of preempt-to-busy to confuse
+        * us.
+        */
+       if (i915_request_completed(next))
+               return true;
+
        if (!can_merge_ctx(prev->hw_context, next->hw_context))
                return false;
 
@@ -893,7 +910,7 @@ static void virtual_xfer_breadcrumbs(struct virtual_engine *ve,
 static struct i915_request *
 last_active(const struct intel_engine_execlists *execlists)
 {
-       struct i915_request * const *last = execlists->active;
+       struct i915_request * const *last = READ_ONCE(execlists->active);
 
        while (*last && i915_request_completed(*last))
                last++;
@@ -1172,21 +1189,6 @@ static void execlists_dequeue(struct intel_engine_cs *engine)
                                continue;
                        }
 
-                       if (i915_request_completed(rq)) {
-                               ve->request = NULL;
-                               ve->base.execlists.queue_priority_hint = INT_MIN;
-                               rb_erase_cached(rb, &execlists->virtual);
-                               RB_CLEAR_NODE(rb);
-
-                               rq->engine = engine;
-                               __i915_request_submit(rq);
-
-                               spin_unlock(&ve->base.active.lock);
-
-                               rb = rb_first_cached(&execlists->virtual);
-                               continue;
-                       }
-
                        if (last && !can_merge_rq(last, rq)) {
                                spin_unlock(&ve->base.active.lock);
                                return; /* leave this for another */
@@ -1237,11 +1239,24 @@ static void execlists_dequeue(struct intel_engine_cs *engine)
                                GEM_BUG_ON(ve->siblings[0] != engine);
                        }
 
-                       __i915_request_submit(rq);
-                       if (!i915_request_completed(rq)) {
+                       if (__i915_request_submit(rq)) {
                                submit = true;
                                last = rq;
                        }
+                       i915_request_put(rq);
+
+                       /*
+                        * Hmm, we have a bunch of virtual engine requests,
+                        * but the first one was already completed (thanks
+                        * preempt-to-busy!). Keep looking at the veng queue
+                        * until we have no more relevant requests (i.e.
+                        * the normal submit queue has higher priority).
+                        */
+                       if (!submit) {
+                               spin_unlock(&ve->base.active.lock);
+                               rb = rb_first_cached(&execlists->virtual);
+                               continue;
+                       }
                }
 
                spin_unlock(&ve->base.active.lock);
@@ -1254,8 +1269,7 @@ static void execlists_dequeue(struct intel_engine_cs *engine)
                int i;
 
                priolist_for_each_request_consume(rq, rn, p, i) {
-                       if (i915_request_completed(rq))
-                               goto skip;
+                       bool merge = true;
 
                        /*
                         * Can we combine this request with the current port?
@@ -1296,14 +1310,23 @@ static void execlists_dequeue(struct intel_engine_cs *engine)
                                    ctx_single_port_submission(rq->hw_context))
                                        goto done;
 
-                               *port = execlists_schedule_in(last, port - execlists->pending);
-                               port++;
+                               merge = false;
                        }
 
-                       last = rq;
-                       submit = true;
-skip:
-                       __i915_request_submit(rq);
+                       if (__i915_request_submit(rq)) {
+                               if (!merge) {
+                                       *port = execlists_schedule_in(last, port - execlists->pending);
+                                       port++;
+                                       last = NULL;
+                               }
+
+                               GEM_BUG_ON(last &&
+                                          !can_merge_ctx(last->hw_context,
+                                                         rq->hw_context));
+
+                               submit = true;
+                               last = rq;
+                       }
                }
 
                rb_erase_cached(&p->node, &execlists->queue);
@@ -1593,8 +1616,11 @@ static void process_csb(struct intel_engine_cs *engine)
 static void __execlists_submission_tasklet(struct intel_engine_cs *const engine)
 {
        lockdep_assert_held(&engine->active.lock);
-       if (!engine->execlists.pending[0])
+       if (!engine->execlists.pending[0]) {
+               rcu_read_lock(); /* protect peeking at execlists->active */
                execlists_dequeue(engine);
+               rcu_read_unlock();
+       }
 }
 
 /*
@@ -2399,10 +2425,14 @@ static void reset_csb_pointers(struct intel_engine_cs *engine)
 
 static struct i915_request *active_request(struct i915_request *rq)
 {
-       const struct list_head * const list = &rq->timeline->requests;
        const struct intel_context * const ce = rq->hw_context;
        struct i915_request *active = NULL;
+       struct list_head *list;
 
+       if (!i915_request_is_active(rq)) /* unwound, but incomplete! */
+               return rq;
+
+       list = &rq->timeline->requests;
        list_for_each_entry_from_reverse(rq, list, link) {
                if (i915_request_completed(rq))
                        break;
@@ -2552,12 +2582,8 @@ static void execlists_cancel_requests(struct intel_engine_cs *engine)
        __execlists_reset(engine, true);
 
        /* Mark all executing requests as skipped. */
-       list_for_each_entry(rq, &engine->active.requests, sched.link) {
-               if (!i915_request_signaled(rq))
-                       dma_fence_set_error(&rq->fence, -EIO);
-
-               i915_request_mark_complete(rq);
-       }
+       list_for_each_entry(rq, &engine->active.requests, sched.link)
+               mark_eio(rq);
 
        /* Flush the queued requests to the timeline list (for retiring). */
        while ((rb = rb_first_cached(&execlists->queue))) {
@@ -2565,10 +2591,8 @@ static void execlists_cancel_requests(struct intel_engine_cs *engine)
                int i;
 
                priolist_for_each_request_consume(rq, rn, p, i) {
-                       list_del_init(&rq->sched.link);
+                       mark_eio(rq);
                        __i915_request_submit(rq);
-                       dma_fence_set_error(&rq->fence, -EIO);
-                       i915_request_mark_complete(rq);
                }
 
                rb_erase_cached(&p->node, &execlists->queue);
@@ -2584,13 +2608,15 @@ static void execlists_cancel_requests(struct intel_engine_cs *engine)
                RB_CLEAR_NODE(rb);
 
                spin_lock(&ve->base.active.lock);
-               if (ve->request) {
-                       ve->request->engine = engine;
-                       __i915_request_submit(ve->request);
-                       dma_fence_set_error(&ve->request->fence, -EIO);
-                       i915_request_mark_complete(ve->request);
+               rq = fetch_and_zero(&ve->request);
+               if (rq) {
+                       mark_eio(rq);
+
+                       rq->engine = engine;
+                       __i915_request_submit(rq);
+                       i915_request_put(rq);
+
                        ve->base.execlists.queue_priority_hint = INT_MIN;
-                       ve->request = NULL;
                }
                spin_unlock(&ve->base.active.lock);
        }
@@ -3594,6 +3620,8 @@ submit_engine:
 static void virtual_submit_request(struct i915_request *rq)
 {
        struct virtual_engine *ve = to_virtual_engine(rq->engine);
+       struct i915_request *old;
+       unsigned long flags;
 
        GEM_TRACE("%s: rq=%llx:%lld\n",
                  ve->base.name,
@@ -3602,15 +3630,31 @@ static void virtual_submit_request(struct i915_request *rq)
 
        GEM_BUG_ON(ve->base.submit_request != virtual_submit_request);
 
-       GEM_BUG_ON(ve->request);
-       GEM_BUG_ON(!list_empty(virtual_queue(ve)));
+       spin_lock_irqsave(&ve->base.active.lock, flags);
+
+       old = ve->request;
+       if (old) { /* background completion event from preempt-to-busy */
+               GEM_BUG_ON(!i915_request_completed(old));
+               __i915_request_submit(old);
+               i915_request_put(old);
+       }
+
+       if (i915_request_completed(rq)) {
+               __i915_request_submit(rq);
+
+               ve->base.execlists.queue_priority_hint = INT_MIN;
+               ve->request = NULL;
+       } else {
+               ve->base.execlists.queue_priority_hint = rq_prio(rq);
+               ve->request = i915_request_get(rq);
 
-       ve->base.execlists.queue_priority_hint = rq_prio(rq);
-       WRITE_ONCE(ve->request, rq);
+               GEM_BUG_ON(!list_empty(virtual_queue(ve)));
+               list_move_tail(&rq->sched.link, virtual_queue(ve));
 
-       list_move_tail(&rq->sched.link, virtual_queue(ve));
+               tasklet_schedule(&ve->base.execlists.tasklet);
+       }
 
-       tasklet_schedule(&ve->base.execlists.tasklet);
+       spin_unlock_irqrestore(&ve->base.active.lock, flags);
 }
 
 static struct ve_bond *
@@ -3631,18 +3675,22 @@ static void
 virtual_bond_execute(struct i915_request *rq, struct dma_fence *signal)
 {
        struct virtual_engine *ve = to_virtual_engine(rq->engine);
+       intel_engine_mask_t allowed, exec;
        struct ve_bond *bond;
 
+       allowed = ~to_request(signal)->engine->mask;
+
        bond = virtual_find_bond(ve, to_request(signal)->engine);
-       if (bond) {
-               intel_engine_mask_t old, new, cmp;
+       if (bond)
+               allowed &= bond->sibling_mask;
 
-               cmp = READ_ONCE(rq->execution_mask);
-               do {
-                       old = cmp;
-                       new = cmp & bond->sibling_mask;
-               } while ((cmp = cmpxchg(&rq->execution_mask, old, new)) != old);
-       }
+       /* Restrict the bonded request to run on only the available engines */
+       exec = READ_ONCE(rq->execution_mask);
+       while (!try_cmpxchg(&rq->execution_mask, &exec, exec & allowed))
+               ;
+
+       /* Prevent the master from being re-run on the bonded engines */
+       to_request(signal)->execution_mask &= ~allowed;
 }
 
 struct intel_context *