On 8/20/2021 15:44, Matthew Brost wrote: > 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 its' -> its > requests as needed. > > Signed-off-by: Matthew Brost > --- > drivers/gpu/drm/i915/gt/intel_context.c | 11 ++-- > .../gpu/drm/i915/gt/uc/intel_guc_submission.c | 63 +++++++++++++------ > 2 files changed, 51 insertions(+), 23 deletions(-) > > diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c > index 00d1aee6d199..5615be32879c 100644 > --- a/drivers/gpu/drm/i915/gt/intel_context.c > +++ b/drivers/gpu/drm/i915/gt/intel_context.c > @@ -528,20 +528,21 @@ struct i915_request *intel_context_create_request(struct intel_context *ce) > > 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)); Should this not check the parent as well/instead? And to be clear, this can be called on regular contexts (where ce == parent) and on both the parent or child contexts of multi-LRC contexts (where ce may or may not match parent)? > > - spin_lock_irqsave(&ce->guc_state.lock, flags); > - list_for_each_entry_reverse(rq, &ce->guc_state.requests, > + spin_lock_irqsave(&parent->guc_state.lock, flags); > + list_for_each_entry_reverse(rq, &parent->guc_state.requests, > sched.link) { > - if (i915_request_completed(rq)) > + if (i915_request_completed(rq) && rq->context == ce) 'rq->context == ce' means: 1. single-LRC context, rq is owned by ce 2. multi-LRC context, ce is child, rq really belongs to ce but is being tracked by parent 3. multi-LRC context, ce is parent, rq really is owned by ce So when 'rq->ce != ce', it means that the request is owned by a different child to 'ce' but within the same multi-LRC group. So we want to ignore that request and keep searching until we find one that is really owned by the target ce? > break; > > - active = rq; > + active = (rq->context == ce) ? rq : active; Would be clearer to say 'if(rq->ce != ce) continue;' and leave 'active = rq;' alone? And again, the intention is to ignore requests that are owned by other members of the same multi-LRC group? Would be good to add some documentation to this function to explain the above (assuming my description is correct?). > } > - 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 f0b60fecf253..e34e0ea9136a 100644 > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > @@ -670,6 +670,11 @@ static int rq_prio(const struct i915_request *rq) > return rq->sched.attr.priority; > } > > +static inline bool is_multi_lrc(struct intel_context *ce) > +{ > + return intel_context_is_parallel(ce); > +} > + > static bool is_multi_lrc_rq(struct i915_request *rq) > { > return intel_context_is_parallel(rq->context); > @@ -1179,10 +1184,13 @@ __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->guc_number_children; If this is a child context, does it not need to pull the child count from the parent? Likewise the list/link pointers below? Or does each child context have a full list of its siblings + parent? > bool skip = false; > + struct intel_context *parent = ce; > > intel_context_get(ce); > > @@ -1209,25 +1217,34 @@ 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 (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; > + GEM_BUG_ON(i915_active_is_idle(&ce->active)); > + head = intel_ring_wrap(ce->ring, rq->head); > > - GEM_BUG_ON(i915_active_is_idle(&ce->active)); > - head = intel_ring_wrap(ce->ring, rq->head); > - __i915_request_reset(rq, stalled); > + if (i915_request_started(rq)) Why change the ordering of the started test versus the wrap/reset call? Is it significant? Why is it now important to be reversed? > + local_stalled = true; > > + __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, guc_child_link); Can this not be put in to the step clause of the for statement? > + } > + > + __unwind_incomplete_requests(parent); > out_put: > - intel_context_put(ce); > + intel_context_put(parent); As above, I think this function would benefit from some comments to explain exactly what is being done and why. John. > } > > void intel_guc_submission_reset(struct intel_guc *guc, bool stalled) > @@ -1248,7 +1265,8 @@ 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); > @@ -1340,7 +1358,8 @@ 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); > @@ -2031,6 +2050,8 @@ 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); > @@ -2068,6 +2089,7 @@ 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); > > @@ -2099,11 +2121,14 @@ 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); > @@ -2117,7 +2142,7 @@ 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); > } > } > @@ -2143,6 +2168,8 @@ 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);