drm/i915/guc: Implement multi-lrc reset

Update context and full GPU reset to work with multi-lrc. The idea is
parent context tracks all the active requests inflight for itself and
its children. The parent context owns the reset replaying / canceling
requests as needed.

v2:
 (John Harrison)
  - Simply loop in find active request
  - Add comments to find ative request / reset loop
v3:
 (John Harrison)
  - s/its'/its/g
  - Fix comment when searching for active request
  - Reorder if state in __guc_reset_context
v4:
 (Kernel test robot)
  - Delete unused is_multi_lrc function

Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211014172005.27155-15-matthew.brost@intel.com

diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c
index 4d95053..709c433 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_context.c
+++ b/drivers/gpu/drm/i915/gt/intel_context.c
@@ -528,20 +528,29 @@ retry:
 
 struct i915_request *intel_context_find_active_request(struct intel_context *ce)
 {
+       struct intel_context *parent = intel_context_to_parent(ce);
        struct i915_request *rq, *active = NULL;
        unsigned long flags;
 
        GEM_BUG_ON(!intel_engine_uses_guc(ce->engine));
 
-       spin_lock_irqsave(&ce->guc_state.lock, flags);
-       list_for_each_entry_reverse(rq, &ce->guc_state.requests,
+       /*
+        * We search the parent list to find an active request on the submitted
+        * context. The parent list contains the requests for all the contexts
+        * in the relationship so we have to do a compare of each request's
+        * context.
+        */
+       spin_lock_irqsave(&parent->guc_state.lock, flags);
+       list_for_each_entry_reverse(rq, &parent->guc_state.requests,
                                    sched.link) {
+               if (rq->context != ce)
+                       continue;
                if (i915_request_completed(rq))
                        break;
 
                active = rq;
        }
-       spin_unlock_irqrestore(&ce->guc_state.lock, flags);
+       spin_unlock_irqrestore(&parent->guc_state.lock, flags);
 
        return active;
 }

diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
index ebb64fb..112b5e6 100644 (file)
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
@@ -1217,10 +1217,15 @@ __unwind_incomplete_requests(struct intel_context *ce)
 
 static void __guc_reset_context(struct intel_context *ce, bool stalled)
 {
+       bool local_stalled;
        struct i915_request *rq;
        unsigned long flags;
        u32 head;
+       int i, number_children = ce->parallel.number_children;
        bool skip = false;
+       struct intel_context *parent = ce;
+
+       GEM_BUG_ON(intel_context_is_child(ce));
 
        intel_context_get(ce);
 
@@ -1246,25 +1251,38 @@ static void __guc_reset_context(struct intel_context *ce, bool stalled)
        if (unlikely(skip))
                goto out_put;
 
-       rq = intel_context_find_active_request(ce);
-       if (!rq) {
-               head = ce->ring->tail;
-               stalled = false;
-               goto out_replay;
-       }
+       /*
+        * For each context in the relationship find the hanging request
+        * resetting each context / request as needed
+        */
+       for (i = 0; i < number_children + 1; ++i) {
+               if (!intel_context_is_pinned(ce))
+                       goto next_context;
+
+               local_stalled = false;
+               rq = intel_context_find_active_request(ce);
+               if (!rq) {
+                       head = ce->ring->tail;
+                       goto out_replay;
+               }
 
-       if (!i915_request_started(rq))
-               stalled = false;
+               if (i915_request_started(rq))
+                       local_stalled = true;
 
-       GEM_BUG_ON(i915_active_is_idle(&ce->active));
-       head = intel_ring_wrap(ce->ring, rq->head);
-       __i915_request_reset(rq, stalled);
+               GEM_BUG_ON(i915_active_is_idle(&ce->active));
+               head = intel_ring_wrap(ce->ring, rq->head);
 
+               __i915_request_reset(rq, local_stalled && stalled);
 out_replay:
-       guc_reset_state(ce, head, stalled);
-       __unwind_incomplete_requests(ce);
+               guc_reset_state(ce, head, local_stalled && stalled);
+next_context:
+               if (i != number_children)
+                       ce = list_next_entry(ce, parallel.child_link);
+       }
+
+       __unwind_incomplete_requests(parent);
 out_put:
-       intel_context_put(ce);
+       intel_context_put(parent);
 }
 
 void intel_guc_submission_reset(struct intel_guc *guc, bool stalled)
@@ -1285,7 +1303,8 @@ void intel_guc_submission_reset(struct intel_guc *guc, bool stalled)
 
                xa_unlock(&guc->context_lookup);
 
-               if (intel_context_is_pinned(ce))
+               if (intel_context_is_pinned(ce) &&
+                   !intel_context_is_child(ce))
                        __guc_reset_context(ce, stalled);
 
                intel_context_put(ce);
@@ -1377,7 +1396,8 @@ void intel_guc_submission_cancel_requests(struct intel_guc *guc)
 
                xa_unlock(&guc->context_lookup);
 
-               if (intel_context_is_pinned(ce))
+               if (intel_context_is_pinned(ce) &&
+                   !intel_context_is_child(ce))
                        guc_cancel_context_requests(ce);
 
                intel_context_put(ce);
@@ -2070,6 +2090,8 @@ static struct i915_sw_fence *guc_context_block(struct intel_context *ce)
        u16 guc_id;
        bool enabled;
 
+       GEM_BUG_ON(intel_context_is_child(ce));
+
        spin_lock_irqsave(&ce->guc_state.lock, flags);
 
        incr_context_blocked(ce);
@@ -2124,6 +2146,7 @@ static void guc_context_unblock(struct intel_context *ce)
        bool enable;
 
        GEM_BUG_ON(context_enabled(ce));
+       GEM_BUG_ON(intel_context_is_child(ce));
 
        spin_lock_irqsave(&ce->guc_state.lock, flags);
 
@@ -2150,11 +2173,14 @@ static void guc_context_unblock(struct intel_context *ce)
 static void guc_context_cancel_request(struct intel_context *ce,
                                       struct i915_request *rq)
 {
+       struct intel_context *block_context =
+               request_to_scheduling_context(rq);
+
        if (i915_sw_fence_signaled(&rq->submit)) {
                struct i915_sw_fence *fence;
 
                intel_context_get(ce);
-               fence = guc_context_block(ce);
+               fence = guc_context_block(block_context);
                i915_sw_fence_wait(fence);
                if (!i915_request_completed(rq)) {
                        __i915_request_skip(rq);
@@ -2168,7 +2194,7 @@ static void guc_context_cancel_request(struct intel_context *ce,
                 */
                flush_work(&ce_to_guc(ce)->ct.requests.worker);
 
-               guc_context_unblock(ce);
+               guc_context_unblock(block_context);
                intel_context_put(ce);
        }
 }
@@ -2194,6 +2220,8 @@ static void guc_context_ban(struct intel_context *ce, struct i915_request *rq)
        intel_wakeref_t wakeref;
        unsigned long flags;
 
+       GEM_BUG_ON(intel_context_is_child(ce));
+
        guc_flush_submissions(guc);
 
        spin_lock_irqsave(&ce->guc_state.lock, flags);