In eliminating the recursion from walking the tree of signalers/waiters
for processing the hold/unhold operations, a crucial error crept in
where we looked at the parent request and not the list element when
processing the list.
Brown paper bag, much?
Closes: https://gitlab.freedesktop.org/drm/intel/issues/1166
Fixes: 748317386afb ("drm/i915/execlists: Offline error capture")
Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Cc: Mika Kuoppala <mika.kuoppala@xxxxxxxxxxxxxxx>
Cc: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>
---
drivers/gpu/drm/i915/gt/intel_lrc.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
index 4bedc66bebb1..21385070ad15 100644
--- a/drivers/gpu/drm/i915/gt/intel_lrc.c
+++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
@@ -2374,10 +2374,10 @@ static void __execlists_hold(struct i915_request *rq)
if (i915_request_is_active(rq))
__i915_request_unsubmit(rq);
- RQ_TRACE(rq, "on hold\n");
clear_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags);
list_move_tail(&rq->sched.link, &rq->engine->active.hold);
i915_request_set_hold(rq);
+ RQ_TRACE(rq, "on hold\n");
for_each_waiter(p, rq) {
struct i915_request *w =
@@ -2393,7 +2393,7 @@ static void __execlists_hold(struct i915_request *rq)
if (i915_request_completed(w))
continue;
- if (i915_request_on_hold(rq))
+ if (i915_request_on_hold(w))
continue;
list_move_tail(&w->sched.link, &list);
@@ -2451,6 +2451,7 @@ static bool execlists_hold(struct intel_engine_cs *engine,
GEM_BUG_ON(i915_request_on_hold(rq));
GEM_BUG_ON(rq->engine != engine);
__execlists_hold(rq);
+ GEM_BUG_ON(list_empty(&engine->active.hold));
unlock:
spin_unlock_irq(&engine->active.lock);
@@ -2486,6 +2487,8 @@ static void __execlists_unhold(struct i915_request *rq)
do {
struct i915_dependency *p;
+ RQ_TRACE(rq, "hold release\n");
+
GEM_BUG_ON(!i915_request_on_hold(rq));
GEM_BUG_ON(!i915_sw_fence_signaled(&rq->submit));
@@ -2494,7 +2497,6 @@ static void __execlists_unhold(struct i915_request *rq)
i915_sched_lookup_priolist(rq->engine,
rq_prio(rq)));
set_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags);
- RQ_TRACE(rq, "hold release\n");
/* Also release any children on this engine that are ready */
for_each_waiter(p, rq) {
@@ -2504,11 +2506,11 @@ static void __execlists_unhold(struct i915_request *rq)
if (w->engine != rq->engine)
continue;
- if (!i915_request_on_hold(rq))
+ if (!i915_request_on_hold(w))
continue;
/* Check that no other parents are also on hold */
- if (hold_request(rq))
+ if (hold_request(w))
continue;
list_move_tail(&w->sched.link, &list);
@@ -2806,6 +2808,7 @@ static void execlists_submit_request(struct i915_request *request)
spin_lock_irqsave(&engine->active.lock, flags);
if (unlikely(ancestor_on_hold(engine, request))) {
+ RQ_TRACE(request, "ancestor on hold\n");
list_add_tail(&request->sched.link, &engine->active.hold);
i915_request_set_hold(request);
} else {
