[Intel-gfx] [RFC PATCH 64/97] drm/i915/guc: Reset implementation for new GuC interface
Matthew Brost
matthew.brost at intel.com
Fri Jun 4 18:02:32 UTC 2021
On Fri, Jun 04, 2021 at 10:16:14AM +0200, Daniel Vetter wrote:
> On Fri, Jun 4, 2021 at 5:25 AM Matthew Brost <matthew.brost at intel.com> wrote:
> >
> > On Wed, Jun 02, 2021 at 03:33:43PM +0100, Tvrtko Ursulin wrote:
> > >
> > > On 06/05/2021 20:14, Matthew Brost wrote:
> > > > Reset implementation for new GuC interface. This is the legacy reset
> > > > implementation which is called when the i915 owns the engine hang check.
> > > > Future patches will offload the engine hang check to GuC but we will
> > > > continue to maintain this legacy path as a fallback and this code path
> > > > is also required if the GuC dies.
> > > >
> > > > With the new GuC interface it is not possible to reset individual
> > > > engines - it is only possible to reset the GPU entirely. This patch
> > > > forces an entire chip reset if any engine hangs.
> > > >
> > > > Cc: John Harrison <john.c.harrison at intel.com>
> > > > Signed-off-by: Matthew Brost <matthew.brost at intel.com>
> > > > ---
> > > > drivers/gpu/drm/i915/gt/intel_context.c | 3 +
> > > > drivers/gpu/drm/i915/gt/intel_context_types.h | 7 +
> > > > drivers/gpu/drm/i915/gt/intel_engine_types.h | 6 +
> > > > .../drm/i915/gt/intel_execlists_submission.c | 40 ++
> > > > drivers/gpu/drm/i915/gt/intel_gt_pm.c | 6 +-
> > > > drivers/gpu/drm/i915/gt/intel_reset.c | 18 +-
> > > > .../gpu/drm/i915/gt/intel_ring_submission.c | 22 +
> > > > drivers/gpu/drm/i915/gt/mock_engine.c | 31 +
> > > > drivers/gpu/drm/i915/gt/uc/intel_guc.c | 16 +-
> > > > drivers/gpu/drm/i915/gt/uc/intel_guc.h | 8 +-
> > > > .../gpu/drm/i915/gt/uc/intel_guc_submission.c | 580 ++++++++++++++----
> > > > drivers/gpu/drm/i915/gt/uc/intel_uc.c | 34 +-
> > > > drivers/gpu/drm/i915/gt/uc/intel_uc.h | 3 +
> > > > drivers/gpu/drm/i915/i915_request.c | 41 +-
> > > > drivers/gpu/drm/i915/i915_request.h | 2 +
> > > > 15 files changed, 643 insertions(+), 174 deletions(-)
> > > >
> > > > diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c
> > > > index b24a1b7a3f88..2f01437056a8 100644
> > > > --- a/drivers/gpu/drm/i915/gt/intel_context.c
> > > > +++ b/drivers/gpu/drm/i915/gt/intel_context.c
> > > > @@ -392,6 +392,9 @@ intel_context_init(struct intel_context *ce, struct intel_engine_cs *engine)
> > > > spin_lock_init(&ce->guc_state.lock);
> > > > INIT_LIST_HEAD(&ce->guc_state.fences);
> > > > + spin_lock_init(&ce->guc_active.lock);
> > > > + INIT_LIST_HEAD(&ce->guc_active.requests);
> > > > +
> > > > ce->guc_id = GUC_INVALID_LRC_ID;
> > > > INIT_LIST_HEAD(&ce->guc_id_link);
> > > > diff --git a/drivers/gpu/drm/i915/gt/intel_context_types.h b/drivers/gpu/drm/i915/gt/intel_context_types.h
> > > > index 6945963a31ba..b63c8cf7823b 100644
> > > > --- a/drivers/gpu/drm/i915/gt/intel_context_types.h
> > > > +++ b/drivers/gpu/drm/i915/gt/intel_context_types.h
> > > > @@ -165,6 +165,13 @@ struct intel_context {
> > > > struct list_head fences;
> > > > } guc_state;
> > > > + struct {
> > > > + /** lock: protects everything in guc_active */
> > > > + spinlock_t lock;
> > > > + /** requests: active requests on this context */
> > > > + struct list_head requests;
> > > > + } guc_active;
> > >
> > > More accounting, yeah, this is more of that where GuC gives with one hand
> > > and takes away with the other. :(
> > >
> >
> > Yep but we probably can drop this once we switch to the DRM scheduler.
> > The drm_gpu_scheduler has a list of jobs and if don't mind searching the
> > whole thing on a reset that will probably work too. I think the only
> > reason we have a per context list is because of feedback I received a
> > a while go saying resets are per context with GuC so keep a list on the
> > context and engine list didn't really fit either. I'll make a to circle
> > back to this when we hook into the DRM scheduler.
>
> Please add a FIXME or similar to the kerneldoc comment for stuff like
> this. We have a lot of things to recheck once the big picture is
> sorted, and it's easy to forget them.
>
Sure, will do in next rev. But I think a lot things like this will come
naturally when we switch over to the DRM scheduler. I didn't quite get
to deleting this list the in my PoC but could clearly see this was no
longer needed and actually have a TODO in the code to delete this.
Matt
> Similar for anything else where we have opens about how to structure
> things once it's cut over.
> -Daniel
>
> >
> > > > +
> > > > /* GuC scheduling state that does not require a lock. */
> > > > atomic_t guc_sched_state_no_lock;
> > > > diff --git a/drivers/gpu/drm/i915/gt/intel_engine_types.h b/drivers/gpu/drm/i915/gt/intel_engine_types.h
> > > > index f7b6eed586ce..b84562b2708b 100644
> > > > --- a/drivers/gpu/drm/i915/gt/intel_engine_types.h
> > > > +++ b/drivers/gpu/drm/i915/gt/intel_engine_types.h
> > > > @@ -432,6 +432,12 @@ struct intel_engine_cs {
> > > > */
> > > > void (*release)(struct intel_engine_cs *engine);
> > > > + /*
> > > > + * Add / remove request from engine active tracking
> > > > + */
> > > > + void (*add_active_request)(struct i915_request *rq);
> > > > + void (*remove_active_request)(struct i915_request *rq);
> > > > +
> > > > struct intel_engine_execlists execlists;
> > > > /*
> > > > diff --git a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
> > > > index 396b1356ea3e..54518b64bdbd 100644
> > > > --- a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
> > > > +++ b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
> > > > @@ -3117,6 +3117,42 @@ static void execlists_park(struct intel_engine_cs *engine)
> > > > cancel_timer(&engine->execlists.preempt);
> > > > }
> > > > +static void add_to_engine(struct i915_request *rq)
> > > > +{
> > > > + lockdep_assert_held(&rq->engine->sched_engine->lock);
> > > > + list_move_tail(&rq->sched.link, &rq->engine->sched_engine->requests);
> > > > +}
> > > > +
> > > > +static void remove_from_engine(struct i915_request *rq)
> > > > +{
> > > > + struct intel_engine_cs *engine, *locked;
> > > > +
> > > > + /*
> > > > + * Virtual engines complicate acquiring the engine timeline lock,
> > > > + * as their rq->engine pointer is not stable until under that
> > > > + * engine lock. The simple ploy we use is to take the lock then
> > > > + * check that the rq still belongs to the newly locked engine.
> > > > + */
> > > > + locked = READ_ONCE(rq->engine);
> > > > + spin_lock_irq(&locked->sched_engine->lock);
> > > > + while (unlikely(locked != (engine = READ_ONCE(rq->engine)))) {
> > > > + spin_unlock(&locked->sched_engine->lock);
> > > > + spin_lock(&engine->sched_engine->lock);
> > > > + locked = engine;
> > > > + }
> > >
> > > Could use i915_request_active_engine although tbf I don't remember why I did
> > > not convert all callers when I added it. Perhaps I just did not find them
> > > all.
> > >
> >
> > I think is a copy paste from the existing code or least at it should be.
> > It just moves implicit execlists behavior from common code to a
> > execlists specific vfunc.
> >
> > > > + list_del_init(&rq->sched.link);
> > > > +
> > > > + clear_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags);
> > > > + clear_bit(I915_FENCE_FLAG_HOLD, &rq->fence.flags);
> > > > +
> > > > + /* Prevent further __await_execution() registering a cb, then flush */
> > > > + set_bit(I915_FENCE_FLAG_ACTIVE, &rq->fence.flags);
> > > > +
> > > > + spin_unlock_irq(&locked->sched_engine->lock);
> > > > +
> > > > + i915_request_notify_execute_cb_imm(rq);
> > > > +}
> > > > +
> > > > static bool can_preempt(struct intel_engine_cs *engine)
> > > > {
> > > > if (INTEL_GEN(engine->i915) > 8)
> > > > @@ -3214,6 +3250,8 @@ logical_ring_default_vfuncs(struct intel_engine_cs *engine)
> > > > engine->cops = &execlists_context_ops;
> > > > engine->request_alloc = execlists_request_alloc;
> > > > engine->bump_serial = execlist_bump_serial;
> > > > + engine->add_active_request = add_to_engine;
> > > > + engine->remove_active_request = remove_from_engine;
> > > > engine->reset.prepare = execlists_reset_prepare;
> > > > engine->reset.rewind = execlists_reset_rewind;
> > > > @@ -3915,6 +3953,8 @@ execlists_create_virtual(struct intel_engine_cs **siblings, unsigned int count)
> > > > ve->base.sched_engine->kick_backend =
> > > > sibling->sched_engine->kick_backend;
> > > > + ve->base.add_active_request = sibling->add_active_request;
> > > > + ve->base.remove_active_request = sibling->remove_active_request;
> > > > ve->base.emit_bb_start = sibling->emit_bb_start;
> > > > ve->base.emit_flush = sibling->emit_flush;
> > > > ve->base.emit_init_breadcrumb = sibling->emit_init_breadcrumb;
> > > > diff --git a/drivers/gpu/drm/i915/gt/intel_gt_pm.c b/drivers/gpu/drm/i915/gt/intel_gt_pm.c
> > > > index aef3084e8b16..463a6ae605a0 100644
> > > > --- a/drivers/gpu/drm/i915/gt/intel_gt_pm.c
> > > > +++ b/drivers/gpu/drm/i915/gt/intel_gt_pm.c
> > > > @@ -174,8 +174,6 @@ static void gt_sanitize(struct intel_gt *gt, bool force)
> > > > if (intel_gt_is_wedged(gt))
> > > > intel_gt_unset_wedged(gt);
> > > > - intel_uc_sanitize(>->uc);
> > > > -
> > > > for_each_engine(engine, gt, id)
> > > > if (engine->reset.prepare)
> > > > engine->reset.prepare(engine);
> > > > @@ -191,6 +189,8 @@ static void gt_sanitize(struct intel_gt *gt, bool force)
> > > > __intel_engine_reset(engine, false);
> > > > }
> > > > + intel_uc_reset(>->uc, false);
> > > > +
> > > > for_each_engine(engine, gt, id)
> > > > if (engine->reset.finish)
> > > > engine->reset.finish(engine);
> > > > @@ -243,6 +243,8 @@ int intel_gt_resume(struct intel_gt *gt)
> > > > goto err_wedged;
> > > > }
> > > > + intel_uc_reset_finish(>->uc);
> > > > +
> > > > intel_rps_enable(>->rps);
> > > > intel_llc_enable(>->llc);
> > > > diff --git a/drivers/gpu/drm/i915/gt/intel_reset.c b/drivers/gpu/drm/i915/gt/intel_reset.c
> > > > index d5094be6d90f..ce3ef26ffe2d 100644
> > > > --- a/drivers/gpu/drm/i915/gt/intel_reset.c
> > > > +++ b/drivers/gpu/drm/i915/gt/intel_reset.c
> > > > @@ -758,6 +758,8 @@ static int gt_reset(struct intel_gt *gt, intel_engine_mask_t stalled_mask)
> > > > __intel_engine_reset(engine, stalled_mask & engine->mask);
> > > > local_bh_enable();
> > > > + intel_uc_reset(>->uc, true);
> > > > +
> > > > intel_ggtt_restore_fences(gt->ggtt);
> > > > return err;
> > > > @@ -782,6 +784,8 @@ static void reset_finish(struct intel_gt *gt, intel_engine_mask_t awake)
> > > > if (awake & engine->mask)
> > > > intel_engine_pm_put(engine);
> > > > }
> > > > +
> > > > + intel_uc_reset_finish(>->uc);
> > > > }
> > > > static void nop_submit_request(struct i915_request *request)
> > > > @@ -835,6 +839,7 @@ static void __intel_gt_set_wedged(struct intel_gt *gt)
> > > > for_each_engine(engine, gt, id)
> > > > if (engine->reset.cancel)
> > > > engine->reset.cancel(engine);
> > > > + intel_uc_cancel_requests(>->uc);
> > > > local_bh_enable();
> > > > reset_finish(gt, awake);
> > > > @@ -1123,6 +1128,9 @@ int __intel_engine_reset_bh(struct intel_engine_cs *engine, const char *msg)
> > > > ENGINE_TRACE(engine, "flags=%lx\n", gt->reset.flags);
> > > > GEM_BUG_ON(!test_bit(I915_RESET_ENGINE + engine->id, >->reset.flags));
> > > > + if (intel_engine_uses_guc(engine))
> > > > + return -ENODEV;
> > > > +
> > > > if (!intel_engine_pm_get_if_awake(engine))
> > > > return 0;
> > > > @@ -1133,13 +1141,10 @@ int __intel_engine_reset_bh(struct intel_engine_cs *engine, const char *msg)
> > > > "Resetting %s for %s\n", engine->name, msg);
> > > > atomic_inc(&engine->i915->gpu_error.reset_engine_count[engine->uabi_class]);
> > > > - if (intel_engine_uses_guc(engine))
> > > > - ret = intel_guc_reset_engine(&engine->gt->uc.guc, engine);
> > > > - else
> > > > - ret = intel_gt_reset_engine(engine);
> > > > + ret = intel_gt_reset_engine(engine);
> > > > if (ret) {
> > > > /* If we fail here, we expect to fallback to a global reset */
> > > > - ENGINE_TRACE(engine, "Failed to reset, err: %d\n", ret);
> > > > + ENGINE_TRACE(engine, "Failed to reset %s, err: %d\n", engine->name, ret);
> > > > goto out;
> > > > }
> > > > @@ -1273,7 +1278,8 @@ void intel_gt_handle_error(struct intel_gt *gt,
> > > > * Try engine reset when available. We fall back to full reset if
> > > > * single reset fails.
> > > > */
> > > > - if (intel_has_reset_engine(gt) && !intel_gt_is_wedged(gt)) {
> > > > + if (!intel_uc_uses_guc_submission(>->uc) &&
> > > > + intel_has_reset_engine(gt) && !intel_gt_is_wedged(gt)) {
> > >
> > > If with guc driver cannot do engine reset, could intel_has_reset_engine just
> > > say false in that case so guc check wouldn't have to be added here? Also
> > > noticed this is the same open I had in 2019. and someone said it can and
> > > would be folded. ;(
> > >
> >
> > Let me look into that before the next rev, I briefly looked at this and
> > it does seem plausible this function could return false. Only concern
> > here is reset code is notoriously delicate so I am wary to change this
> > in this series. We have a live list of follow ups, this could be
> > included if it doesn't get fixed in this patch.
> >
> > > > local_bh_disable();
> > > > for_each_engine_masked(engine, gt, engine_mask, tmp) {
> > > > BUILD_BUG_ON(I915_RESET_MODESET >= I915_RESET_ENGINE);
> > > > diff --git a/drivers/gpu/drm/i915/gt/intel_ring_submission.c b/drivers/gpu/drm/i915/gt/intel_ring_submission.c
> > > > index 39dd7c4ed0a9..7d05bf16094c 100644
> > > > --- a/drivers/gpu/drm/i915/gt/intel_ring_submission.c
> > > > +++ b/drivers/gpu/drm/i915/gt/intel_ring_submission.c
> > > > @@ -1050,6 +1050,25 @@ static void ring_bump_serial(struct intel_engine_cs *engine)
> > > > engine->serial++;
> > > > }
> > > > +static void add_to_engine(struct i915_request *rq)
> > > > +{
> > > > + lockdep_assert_held(&rq->engine->sched_engine->lock);
> > > > + list_move_tail(&rq->sched.link, &rq->engine->sched_engine->requests);
> > > > +}
> > > > +
> > > > +static void remove_from_engine(struct i915_request *rq)
> > > > +{
> > > > + spin_lock_irq(&rq->engine->sched_engine->lock);
> > > > + list_del_init(&rq->sched.link);
> > > > +
> > > > + /* Prevent further __await_execution() registering a cb, then flush */
> > > > + set_bit(I915_FENCE_FLAG_ACTIVE, &rq->fence.flags);
> > > > +
> > > > + spin_unlock_irq(&rq->engine->sched_engine->lock);
> > > > +
> > > > + i915_request_notify_execute_cb_imm(rq);
> > > > +}
> > > > +
> > > > static void setup_common(struct intel_engine_cs *engine)
> > > > {
> > > > struct drm_i915_private *i915 = engine->i915;
> > > > @@ -1067,6 +1086,9 @@ static void setup_common(struct intel_engine_cs *engine)
> > > > engine->reset.cancel = reset_cancel;
> > > > engine->reset.finish = reset_finish;
> > > > + engine->add_active_request = add_to_engine;
> > > > + engine->remove_active_request = remove_from_engine;
> > > > +
> > > > engine->cops = &ring_context_ops;
> > > > engine->request_alloc = ring_request_alloc;
> > > > engine->bump_serial = ring_bump_serial;
> > > > diff --git a/drivers/gpu/drm/i915/gt/mock_engine.c b/drivers/gpu/drm/i915/gt/mock_engine.c
> > > > index 4d023b5cd5da..dccf5fce980a 100644
> > > > --- a/drivers/gpu/drm/i915/gt/mock_engine.c
> > > > +++ b/drivers/gpu/drm/i915/gt/mock_engine.c
> > > > @@ -235,6 +235,35 @@ static void mock_submit_request(struct i915_request *request)
> > > > spin_unlock_irqrestore(&engine->hw_lock, flags);
> > > > }
> > > > +static void mock_add_to_engine(struct i915_request *rq)
> > > > +{
> > > > + lockdep_assert_held(&rq->engine->sched_engine->lock);
> > > > + list_move_tail(&rq->sched.link, &rq->engine->sched_engine->requests);
> > > > +}
> > > > +
> > > > +static void mock_remove_from_engine(struct i915_request *rq)
> > > > +{
> > > > + struct intel_engine_cs *engine, *locked;
> > > > +
> > > > + /*
> > > > + * Virtual engines complicate acquiring the engine timeline lock,
> > > > + * as their rq->engine pointer is not stable until under that
> > > > + * engine lock. The simple ploy we use is to take the lock then
> > > > + * check that the rq still belongs to the newly locked engine.
> > > > + */
> > > > +
> > > > + locked = READ_ONCE(rq->engine);
> > > > + spin_lock_irq(&locked->sched_engine->lock);
> > > > + while (unlikely(locked != (engine = READ_ONCE(rq->engine)))) {
> > > > + spin_unlock(&locked->sched_engine->lock);
> > > > + spin_lock(&engine->sched_engine->lock);
> > > > + locked = engine;
> > > > + }
> > > > + list_del_init(&rq->sched.link);
> > > > + spin_unlock_irq(&locked->sched_engine->lock);
> > > > +}
> > > > +
> > > > +
> > > > static void mock_reset_prepare(struct intel_engine_cs *engine)
> > > > {
> > > > }
> > > > @@ -327,6 +356,8 @@ struct intel_engine_cs *mock_engine(struct drm_i915_private *i915,
> > > > engine->base.emit_flush = mock_emit_flush;
> > > > engine->base.emit_fini_breadcrumb = mock_emit_breadcrumb;
> > > > engine->base.submit_request = mock_submit_request;
> > > > + engine->base.add_active_request = mock_add_to_engine;
> > > > + engine->base.remove_active_request = mock_remove_from_engine;
> > > > engine->base.reset.prepare = mock_reset_prepare;
> > > > engine->base.reset.rewind = mock_reset_rewind;
> > > > diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc.c b/drivers/gpu/drm/i915/gt/uc/intel_guc.c
> > > > index 235c1997f32d..864b14e313a3 100644
> > > > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc.c
> > > > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.c
> > > > @@ -146,6 +146,9 @@ static void gen11_disable_guc_interrupts(struct intel_guc *guc)
> > > > {
> > > > struct intel_gt *gt = guc_to_gt(guc);
> > > > + if (!guc->interrupts.enabled)
> > > > + return;
> > > > +
> > > > spin_lock_irq(>->irq_lock);
> > > > guc->interrupts.enabled = false;
> > > > @@ -579,19 +582,6 @@ int intel_guc_suspend(struct intel_guc *guc)
> > > > return 0;
> > > > }
> > > > -/**
> > > > - * intel_guc_reset_engine() - ask GuC to reset an engine
> > > > - * @guc: intel_guc structure
> > > > - * @engine: engine to be reset
> > > > - */
> > > > -int intel_guc_reset_engine(struct intel_guc *guc,
> > > > - struct intel_engine_cs *engine)
> > > > -{
> > > > - /* XXX: to be implemented with submission interface rework */
> > > > -
> > > > - return -ENODEV;
> > > > -}
> > > > -
> > > > /**
> > > > * intel_guc_resume() - notify GuC resuming from suspend state
> > > > * @guc: the guc
> > > > diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc.h b/drivers/gpu/drm/i915/gt/uc/intel_guc.h
> > > > index 47eaa69809e8..afea04d56494 100644
> > > > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc.h
> > > > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.h
> > > > @@ -243,14 +243,16 @@ static inline void intel_guc_disable_msg(struct intel_guc *guc, u32 mask)
> > > > int intel_guc_wait_for_idle(struct intel_guc *guc, long timeout);
> > > > -int intel_guc_reset_engine(struct intel_guc *guc,
> > > > - struct intel_engine_cs *engine);
> > > > -
> > > > int intel_guc_deregister_done_process_msg(struct intel_guc *guc,
> > > > const u32 *msg, u32 len);
> > > > int intel_guc_sched_done_process_msg(struct intel_guc *guc,
> > > > const u32 *msg, u32 len);
> > > > +void intel_guc_submission_reset_prepare(struct intel_guc *guc);
> > > > +void intel_guc_submission_reset(struct intel_guc *guc, bool stalled);
> > > > +void intel_guc_submission_reset_finish(struct intel_guc *guc);
> > > > +void intel_guc_submission_cancel_requests(struct intel_guc *guc);
> > > > +
> > > > void intel_guc_load_status(struct intel_guc *guc, struct drm_printer *p);
> > > > #endif
> > > > 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 80b89171b35a..8c093bc2d3a4 100644
> > > > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
> > > > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
> > > > @@ -140,7 +140,7 @@ context_wait_for_deregister_to_register(struct intel_context *ce)
> > > > static inline void
> > > > set_context_wait_for_deregister_to_register(struct intel_context *ce)
> > > > {
> > > > - /* Only should be called from guc_lrc_desc_pin() */
> > > > + /* Only should be called from guc_lrc_desc_pin() without lock */
> > > > ce->guc_state.sched_state |=
> > > > SCHED_STATE_WAIT_FOR_DEREGISTER_TO_REGISTER;
> > > > }
> > > > @@ -240,15 +240,31 @@ static int guc_lrc_desc_pool_create(struct intel_guc *guc)
> > > > static void guc_lrc_desc_pool_destroy(struct intel_guc *guc)
> > > > {
> > > > + guc->lrc_desc_pool_vaddr = NULL;
> > > > i915_vma_unpin_and_release(&guc->lrc_desc_pool, I915_VMA_RELEASE_MAP);
> > > > }
> > > > +static inline bool guc_submission_initialized(struct intel_guc *guc)
> > > > +{
> > > > + return guc->lrc_desc_pool_vaddr != NULL;
> > > > +}
> > > > +
> > > > static inline void reset_lrc_desc(struct intel_guc *guc, u32 id)
> > > > {
> > > > - struct guc_lrc_desc *desc = __get_lrc_desc(guc, id);
> > > > + if (likely(guc_submission_initialized(guc))) {
> > > > + struct guc_lrc_desc *desc = __get_lrc_desc(guc, id);
> > > > + unsigned long flags;
> > > > - memset(desc, 0, sizeof(*desc));
> > > > - xa_erase_irq(&guc->context_lookup, id);
> > > > + memset(desc, 0, sizeof(*desc));
> > > > +
> > > > + /*
> > > > + * xarray API doesn't have xa_erase_irqsave wrapper, so calling
> > > > + * the lower level functions directly.
> > > > + */
> > > > + xa_lock_irqsave(&guc->context_lookup, flags);
> > > > + __xa_erase(&guc->context_lookup, id);
> > > > + xa_unlock_irqrestore(&guc->context_lookup, flags);
> > > > + }
> > > > }
> > > > static inline bool lrc_desc_registered(struct intel_guc *guc, u32 id)
> > > > @@ -259,7 +275,15 @@ static inline bool lrc_desc_registered(struct intel_guc *guc, u32 id)
> > > > static inline void set_lrc_desc_registered(struct intel_guc *guc, u32 id,
> > > > struct intel_context *ce)
> > > > {
> > > > - xa_store_irq(&guc->context_lookup, id, ce, GFP_ATOMIC);
> > > > + unsigned long flags;
> > > > +
> > > > + /*
> > > > + * xarray API doesn't have xa_save_irqsave wrapper, so calling the
> > > > + * lower level functions directly.
> > > > + */
> > > > + xa_lock_irqsave(&guc->context_lookup, flags);
> > > > + __xa_store(&guc->context_lookup, id, ce, GFP_ATOMIC);
> > > > + xa_unlock_irqrestore(&guc->context_lookup, flags);
> > > > }
> > > > static int guc_submission_busy_loop(struct intel_guc* guc,
> > > > @@ -330,6 +354,8 @@ int intel_guc_wait_for_idle(struct intel_guc *guc, long timeout)
> > > > interruptible, timeout);
> > > > }
> > > > +static int guc_lrc_desc_pin(struct intel_context *ce, bool loop);
> > > > +
> > > > static int guc_add_request(struct intel_guc *guc, struct i915_request *rq)
> > > > {
> > > > int err;
> > > > @@ -337,11 +363,22 @@ static int guc_add_request(struct intel_guc *guc, struct i915_request *rq)
> > > > u32 action[3];
> > > > int len = 0;
> > > > u32 g2h_len_dw = 0;
> > > > - bool enabled = context_enabled(ce);
> > > > + bool enabled;
> > > > GEM_BUG_ON(!atomic_read(&ce->guc_id_ref));
> > > > GEM_BUG_ON(context_guc_id_invalid(ce));
> > > > + /*
> > > > + * Corner case where the GuC firmware was blown away and reloaded while
> > > > + * this context was pinned.
> > > > + */
> > > > + if (unlikely(!lrc_desc_registered(guc, ce->guc_id))) {
> > > > + err = guc_lrc_desc_pin(ce, false);
> > > > + if (unlikely(err))
> > > > + goto out;
> > > > + }
> > > > + enabled = context_enabled(ce);
> > > > +
> > > > if (!enabled) {
> > > > action[len++] = INTEL_GUC_ACTION_SCHED_CONTEXT_MODE_SET;
> > > > action[len++] = ce->guc_id;
> > > > @@ -364,6 +401,7 @@ static int guc_add_request(struct intel_guc *guc, struct i915_request *rq)
> > > > intel_context_put(ce);
> > > > }
> > > > +out:
> > > > return err;
> > > > }
> > > > @@ -418,15 +456,10 @@ static int guc_dequeue_one_context(struct intel_guc *guc)
> > > > if (submit) {
> > > > guc_set_lrc_tail(last);
> > > > resubmit:
> > > > - /*
> > > > - * We only check for -EBUSY here even though it is possible for
> > > > - * -EDEADLK to be returned. If -EDEADLK is returned, the GuC has
> > > > - * died and a full GPU needs to be done. The hangcheck will
> > > > - * eventually detect that the GuC has died and trigger this
> > > > - * reset so no need to handle -EDEADLK here.
> > > > - */
> > > > ret = guc_add_request(guc, last);
> > > > - if (ret == -EBUSY) {
> > > > + if (unlikely(ret == -EDEADLK))
> > > > + goto deadlk;
> > > > + else if (ret == -EBUSY) {
> > > > i915_sched_engine_kick(sched_engine);
> > > > guc->stalled_request = last;
> > > > return false;
> > > > @@ -436,6 +469,11 @@ static int guc_dequeue_one_context(struct intel_guc *guc)
> > > > guc->stalled_request = NULL;
> > > > return submit;
> > > > +
> > > > +deadlk:
> > > > + sched_engine->tasklet.callback = NULL;
> > > > + tasklet_disable_nosync(&sched_engine->tasklet);
> > > > + return false;
> > > > }
> > > > static void guc_submission_tasklet(struct tasklet_struct *t)
> > > > @@ -462,29 +500,165 @@ static void cs_irq_handler(struct intel_engine_cs *engine, u16 iir)
> > > > intel_engine_signal_breadcrumbs(engine);
> > > > }
> > > > -static void guc_reset_prepare(struct intel_engine_cs *engine)
> > > > +static void __guc_context_destroy(struct intel_context *ce);
> > > > +static void release_guc_id(struct intel_guc *guc, struct intel_context *ce);
> > > > +static void guc_signal_context_fence(struct intel_context *ce);
> > > > +
> > > > +static void scrub_guc_desc_for_outstanding_g2h(struct intel_guc *guc)
> > > > {
> > > > - struct i915_sched_engine * const sched_engine = engine->sched_engine;
> > > > + struct intel_context *ce;
> > > > + unsigned long index, flags;
> > > > + bool pending_disable, pending_enable, deregister, destroyed;
> > > > - ENGINE_TRACE(engine, "\n");
> > > > + xa_for_each(&guc->context_lookup, index, ce) {
> > > > + /* Flush context */
> > > > + spin_lock_irqsave(&ce->guc_state.lock, flags);
> > > > + spin_unlock_irqrestore(&ce->guc_state.lock, flags);
> > >
> > > Very unusual pattern - what does it do?
> > >
> >
> > The comment below tries to explain this. Basically by cycling the lock
> > it guarantees submission_disabled() is visible to all callers that touch
> > the below flags.
> >
> > > > +
> > > > + /*
> > > > + * Once we are at this point submission_disabled() is guaranteed
> > > > + * to visible to all callers who set the below flags (see above
> > > > + * flush and flushes in reset_prepare). If submission_disabled()
> > > > + * is set, the caller shouldn't set these flags.
> > > > + */
> > > > +
> > > > + destroyed = context_destroyed(ce);
> > > > + pending_enable = context_pending_enable(ce);
> > > > + pending_disable = context_pending_disable(ce);
> > > > + deregister = context_wait_for_deregister_to_register(ce);
> > > > + init_sched_state(ce);
> > > > +
> > > > + if (pending_enable || destroyed || deregister) {
> > > > + atomic_dec(&guc->outstanding_submission_g2h);
> > > > + if (deregister)
> > > > + guc_signal_context_fence(ce);
> > > > + if (destroyed) {
> > > > + release_guc_id(guc, ce);
> > > > + __guc_context_destroy(ce);
> > > > + }
> > > > + if (pending_enable|| deregister)
> > > > + intel_context_put(ce);
> > > > + }
> > > > +
> > > > + /* Not mutualy exclusive with above if statement. */
> > > > + if (pending_disable) {
> > > > + guc_signal_context_fence(ce);
> > > > + intel_context_sched_disable_unpin(ce);
> > > > + atomic_dec(&guc->outstanding_submission_g2h);
> > > > + intel_context_put(ce);
> > > > + }
> > >
> > > Yeah this function is a taste of the taste machine I think is _extremely_
> > > hard to review and know with any confidence it does the right thing.
> > >
> >
> > What is the other option? Block everytime we issue an asynchronous
> > command to the GuC? If we want to do everyting asynchronously we have to
> > track state and take further actions when the GuC finally responds. We
> > also have to deal with the GuC dying and taking those actions on our
> > own.
> >
> > Luckily we do have several other aside from myself that do understand
> > this quite well.
> >
> > > > + }
> > > > +}
> > > > +
> > > > +static inline bool
> > > > +submission_disabled(struct intel_guc *guc)
> > > > +{
> > > > + struct i915_sched_engine * const sched_engine = guc->sched_engine;
> > > > +
> > > > + return unlikely(!__tasklet_is_enabled(&sched_engine->tasklet));
> > > > +}
> > > > +
> > > > +static void disable_submission(struct intel_guc *guc)
> > > > +{
> > > > + struct i915_sched_engine * const sched_engine = guc->sched_engine;
> > > > +
> > > > + if (__tasklet_is_enabled(&sched_engine->tasklet)) {
> > > > + GEM_BUG_ON(!guc->ct.enabled);
> > > > + __tasklet_disable_sync_once(&sched_engine->tasklet);
> > > > + sched_engine->tasklet.callback = NULL;
> > > > + }
> > > > +}
> > > > +
> > > > +static void enable_submission(struct intel_guc *guc)
> > > > +{
> > > > + struct i915_sched_engine * const sched_engine = guc->sched_engine;
> > > > + unsigned long flags;
> > > > +
> > > > + spin_lock_irqsave(&guc->sched_engine->lock, flags);
> > > > + sched_engine->tasklet.callback = guc_submission_tasklet;
> > > > + wmb();
> > >
> > > All memory barriers must be documented.
> > >
> >
> > Found that out from checkpatch the other day, will fix.
> >
> > > > + if (!__tasklet_is_enabled(&sched_engine->tasklet) &&
> > > > + __tasklet_enable(&sched_engine->tasklet)) {
> > > > + GEM_BUG_ON(!guc->ct.enabled);
> > > > +
> > > > + /* And kick in case we missed a new request submission. */
> > > > + i915_sched_engine_hi_kick(sched_engine);
> > > > + }
> > > > + spin_unlock_irqrestore(&guc->sched_engine->lock, flags);
> > > > +}
> > > > +
> > > > +static void guc_flush_submissions(struct intel_guc *guc)
> > > > +{
> > > > + struct i915_sched_engine * const sched_engine = guc->sched_engine;
> > > > + unsigned long flags;
> > > > +
> > > > + spin_lock_irqsave(&sched_engine->lock, flags);
> > > > + spin_unlock_irqrestore(&sched_engine->lock, flags);
> > >
> > > Oh right, more of this. No idea.
> > >
> >
> > Same as above. If you change some state then cycle a lock it is
> > guaranteed that state is visible next time someone grabs the lock. I do
> > explain these races in the documentation patch near the end of the
> > series. Without a BKL I don't see how else to avoid these reset races.
> >
> > > > +}
> > > > +
> > > > +void intel_guc_submission_reset_prepare(struct intel_guc *guc)
> > > > +{
> > > > + int i;
> > > > +
> > > > + if (unlikely(!guc_submission_initialized(guc)))
> > > > + /* Reset called during driver load? GuC not yet initialised! */
> > > > + return;
> > > > +
> > > > + disable_submission(guc);
> > > > + guc->interrupts.disable(guc);
> > > > +
> > > > + /* Flush IRQ handler */
> > > > + spin_lock_irq(&guc_to_gt(guc)->irq_lock);
> > > > + spin_unlock_irq(&guc_to_gt(guc)->irq_lock);
> > > > +
> > > > + guc_flush_submissions(guc);
> > > > /*
> > > > - * Prevent request submission to the hardware until we have
> > > > - * completed the reset in i915_gem_reset_finish(). If a request
> > > > - * is completed by one engine, it may then queue a request
> > > > - * to a second via its sched_engine->tasklet *just* as we are
> > > > - * calling engine->init_hw() and also writing the ELSP.
> > > > - * Turning off the sched_engine->tasklet until the reset is over
> > > > - * prevents the race.
> > > > + * Handle any outstanding G2Hs before reset. Call IRQ handler directly
> > > > + * each pass as interrupt have been disabled. We always scrub for
> > > > + * outstanding G2H as it is possible for outstanding_submission_g2h to
> > > > + * be incremented after the context state update.
> > > > */
> > > > - __tasklet_disable_sync_once(&sched_engine->tasklet);
> > > > + for (i = 0; i < 4 && atomic_read(&guc->outstanding_submission_g2h); ++i) {
> > >
> > > Why is four the magic number and what happens if it is not enough?
> > >
> >
> > I just picked a number. Regardless if the normal G2H path processes all the
> > G2H we scrub all the context state for lost ones.
> >
> > > > + intel_guc_to_host_event_handler(guc);
> > > > +#define wait_for_reset(guc, wait_var) \
> > > > + guc_wait_for_pending_msg(guc, wait_var, false, (HZ / 20))
> > > > + do {
> > > > + wait_for_reset(guc, &guc->outstanding_submission_g2h);
> > > > + } while (!list_empty(&guc->ct.requests.incoming));
> > > > + }
> > > > + scrub_guc_desc_for_outstanding_g2h(guc);
> > > > +}
> > > > +
> > > > +static struct intel_engine_cs *
> > > > +guc_virtual_get_sibling(struct intel_engine_cs *ve, unsigned int sibling)
> > > > +{
> > > > + struct intel_engine_cs *engine;
> > > > + intel_engine_mask_t tmp, mask = ve->mask;
> > > > + unsigned int num_siblings = 0;
> > > > +
> > > > + for_each_engine_masked(engine, ve->gt, mask, tmp)
> > > > + if (num_siblings++ == sibling)
> > > > + return engine;
> > >
> > > Not sure how often is this used overall and whether just storing the array
> > > in ve could be justified.
> > >
> >
> > It really is only used with sibling == 0, so it should be fast.
> >
> > > > +
> > > > + return NULL;
> > > > +}
> > > > +
> > > > +static inline struct intel_engine_cs *
> > > > +__context_to_physical_engine(struct intel_context *ce)
> > > > +{
> > > > + struct intel_engine_cs *engine = ce->engine;
> > > > +
> > > > + if (intel_engine_is_virtual(engine))
> > > > + engine = guc_virtual_get_sibling(engine, 0);
> > > > +
> > > > + return engine;
> > > > }
> > > > -static void guc_reset_state(struct intel_context *ce,
> > > > - struct intel_engine_cs *engine,
> > > > - u32 head,
> > > > - bool scrub)
> > > > +static void guc_reset_state(struct intel_context *ce, u32 head, bool scrub)
> > > > {
> > > > + struct intel_engine_cs *engine = __context_to_physical_engine(ce);
> > > > +
> > > > GEM_BUG_ON(!intel_context_is_pinned(ce));
> > > > /*
> > > > @@ -502,42 +676,147 @@ static void guc_reset_state(struct intel_context *ce,
> > > > lrc_update_regs(ce, engine, head);
> > > > }
> > > > -static void guc_reset_rewind(struct intel_engine_cs *engine, bool stalled)
> > > > +static void guc_reset_nop(struct intel_engine_cs *engine)
> > > > {
> > > > - struct intel_engine_execlists * const execlists = &engine->execlists;
> > > > - struct i915_request *rq;
> > > > +}
> > > > +
> > > > +static void guc_rewind_nop(struct intel_engine_cs *engine, bool stalled)
> > > > +{
> > > > +}
> > > > +
> > > > +static void
> > > > +__unwind_incomplete_requests(struct intel_context *ce)
> > > > +{
> > > > + struct i915_request *rq, *rn;
> > > > + struct list_head *pl;
> > > > + int prio = I915_PRIORITY_INVALID;
> > > > + struct i915_sched_engine * const sched_engine =
> > > > + ce->engine->sched_engine;
> > > > unsigned long flags;
> > > > - spin_lock_irqsave(&engine->sched_engine->lock, flags);
> > > > + spin_lock_irqsave(&sched_engine->lock, flags);
> > > > + spin_lock(&ce->guc_active.lock);
> > > > + list_for_each_entry_safe(rq, rn,
> > > > + &ce->guc_active.requests,
> > > > + sched.link) {
> > > > + if (i915_request_completed(rq))
> > > > + continue;
> > > > +
> > > > + list_del_init(&rq->sched.link);
> > > > + spin_unlock(&ce->guc_active.lock);
> > >
> > > Drops the lock and continues iterating the same list is safe? Comment needed
> > > I think and I do remember I worried about this, or similar instances, in GuC
> > > code before.
> > >
> >
> > We only need the active lock for ce->guc_active.requests list. It is
> > indeed safe to drop the lock.
> >
> > > > +
> > > > + __i915_request_unsubmit(rq);
> > > > +
> > > > + /* Push the request back into the queue for later resubmission. */
> > > > + GEM_BUG_ON(rq_prio(rq) == I915_PRIORITY_INVALID);
> > > > + if (rq_prio(rq) != prio) {
> > > > + prio = rq_prio(rq);
> > > > + pl = i915_sched_lookup_priolist(sched_engine, prio);
> > > > + }
> > > > + GEM_BUG_ON(i915_sched_engine_is_empty(sched_engine));
> > > > - /* Push back any incomplete requests for replay after the reset. */
> > > > - rq = execlists_unwind_incomplete_requests(execlists);
> > > > - if (!rq)
> > > > - goto out_unlock;
> > > > + list_add_tail(&rq->sched.link, pl);
> > > > + set_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags);
> > > > +
> > > > + spin_lock(&ce->guc_active.lock);
> > > > + }
> > > > + spin_unlock(&ce->guc_active.lock);
> > > > + spin_unlock_irqrestore(&sched_engine->lock, flags);
> > > > +}
> > > > +
> > > > +static struct i915_request *context_find_active_request(struct intel_context *ce)
> > > > +{
> > > > + struct i915_request *rq, *active = NULL;
> > > > + unsigned long flags;
> > > > +
> > > > + spin_lock_irqsave(&ce->guc_active.lock, flags);
> > > > + list_for_each_entry_reverse(rq, &ce->guc_active.requests,
> > > > + sched.link) {
> > > > + if (i915_request_completed(rq))
> > > > + break;
> > > > +
> > > > + active = rq;
> > > > + }
> > > > + spin_unlock_irqrestore(&ce->guc_active.lock, flags);
> > > > +
> > > > + return active;
> > > > +}
> > > > +
> > > > +static void __guc_reset_context(struct intel_context *ce, bool stalled)
> > > > +{
> > > > + struct i915_request *rq;
> > > > + u32 head;
> > > > +
> > > > + /*
> > > > + * GuC will implicitly mark the context as non-schedulable
> > > > + * when it sends the reset notification. Make sure our state
> > > > + * reflects this change. The context will be marked enabled
> > > > + * on resubmission.
> > > > + */
> > > > + clr_context_enabled(ce);
> > > > +
> > > > + rq = context_find_active_request(ce);
> > > > + if (!rq) {
> > > > + head = ce->ring->tail;
> > > > + stalled = false;
> > > > + 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);
> > > > __i915_request_reset(rq, stalled);
> > > > - guc_reset_state(rq->context, engine, rq->head, stalled);
> > > > -out_unlock:
> > > > - spin_unlock_irqrestore(&engine->sched_engine->lock, flags);
> > > > +out_replay:
> > > > + guc_reset_state(ce, head, stalled);
> > > > + __unwind_incomplete_requests(ce);
> > > > +}
> > > > +
> > > > +void intel_guc_submission_reset(struct intel_guc *guc, bool stalled)
> > > > +{
> > > > + struct intel_context *ce;
> > > > + unsigned long index;
> > > > +
> > > > + if (unlikely(!guc_submission_initialized(guc)))
> > > > + /* Reset called during driver load? GuC not yet initialised! */
> > > > + return;
> > > > +
> > > > + xa_for_each(&guc->context_lookup, index, ce)
> > > > + if (intel_context_is_pinned(ce))
> > > > + __guc_reset_context(ce, stalled);
> > > > +
> > > > + /* GuC is blown away, drop all references to contexts */
> > > > + xa_destroy(&guc->context_lookup);
> > > > +}
> > > > +
> > > > +static void guc_cancel_context_requests(struct intel_context *ce)
> > > > +{
> > > > + struct i915_sched_engine *sched_engine = ce_to_guc(ce)->sched_engine;
> > > > + struct i915_request *rq;
> > > > + unsigned long flags;
> > > > +
> > > > + /* Mark all executing requests as skipped. */
> > > > + spin_lock_irqsave(&sched_engine->lock, flags);
> > > > + spin_lock(&ce->guc_active.lock);
> > > > + list_for_each_entry(rq, &ce->guc_active.requests, sched.link)
> > > > + i915_request_put(i915_request_mark_eio(rq));
> > > > + spin_unlock(&ce->guc_active.lock);
> > > > + spin_unlock_irqrestore(&sched_engine->lock, flags);
> > >
> > > I suppose somewhere it will need to be documented what are the two locks
> > > protecting and why both are needed at some places.
> > >
> >
> > Yep, I have a locking section the doc patch near the end of the series.
> > Basically here is we don't want any new submissions processed when we
> > are canceling requests - that is the outer lock. The inner lock again
> > ce->guc_active.requests list.
> >
> > BTW - I think I am overly careful with the locks (when in doubt grab a
> > lock) in the reset / cancel code as there is no expectation that this
> > needs to perform well and resets are by far the racest code in the i915.
> >
> > > > }
> > > > -static void guc_reset_cancel(struct intel_engine_cs *engine)
> > > > +static void
> > > > +guc_cancel_sched_engine_requests(struct i915_sched_engine *sched_engine)
> > > > {
> > > > - struct i915_sched_engine * const sched_engine = engine->sched_engine;
> > > > struct i915_request *rq, *rn;
> > > > struct rb_node *rb;
> > > > unsigned long flags;
> > > > /* Can be called during boot if GuC fails to load */
> > > > - if (!engine->gt)
> > > > + if (!sched_engine)
> > > > return;
> > > > - ENGINE_TRACE(engine, "\n");
> > > > -
> > > > /*
> > > > * Before we call engine->cancel_requests(), we should have exclusive
> > > > * access to the submission state. This is arranged for us by the
> > > > @@ -552,13 +831,7 @@ static void guc_reset_cancel(struct intel_engine_cs *engine)
> > > > * submission's irq state, we also wish to remind ourselves that
> > > > * it is irq state.)
> > > > */
> > > > - spin_lock_irqsave(&engine->sched_engine->lock, flags);
> > > > -
> > > > - /* Mark all executing requests as skipped. */
> > > > - list_for_each_entry(rq, &engine->sched_engine->requests, sched.link) {
> > > > - i915_request_set_error_once(rq, -EIO);
> > > > - i915_request_mark_complete(rq);
> > > > - }
> > > > + spin_lock_irqsave(&sched_engine->lock, flags);
> > > > /* Flush the queued requests to the timeline list (for retiring). */
> > > > while ((rb = rb_first_cached(&sched_engine->queue))) {
> > > > @@ -566,9 +839,10 @@ static void guc_reset_cancel(struct intel_engine_cs *engine)
> > > > priolist_for_each_request_consume(rq, rn, p) {
> > > > list_del_init(&rq->sched.link);
> > > > +
> > > > __i915_request_submit(rq);
> > > > - dma_fence_set_error(&rq->fence, -EIO);
> > > > - i915_request_mark_complete(rq);
> > > > +
> > > > + i915_request_put(i915_request_mark_eio(rq));
> > > > }
> > > > rb_erase_cached(&p->node, &sched_engine->queue);
> > > > @@ -580,19 +854,41 @@ static void guc_reset_cancel(struct intel_engine_cs *engine)
> > > > sched_engine->queue_priority_hint = INT_MIN;
> > > > sched_engine->queue = RB_ROOT_CACHED;
> > > > - spin_unlock_irqrestore(&engine->sched_engine->lock, flags);
> > > > + spin_unlock_irqrestore(&sched_engine->lock, flags);
> > > > }
> > > > -static void guc_reset_finish(struct intel_engine_cs *engine)
> > > > +void intel_guc_submission_cancel_requests(struct intel_guc *guc)
> > > > {
> > > > - struct i915_sched_engine * const sched_engine = engine->sched_engine;
> > > > + struct intel_context *ce;
> > > > + unsigned long index;
> > > > - if (__tasklet_enable(&sched_engine->tasklet))
> > > > - /* And kick in case we missed a new request submission. */
> > > > - i915_sched_engine_hi_kick(sched_engine);
> > > > + xa_for_each(&guc->context_lookup, index, ce)
> > > > + if (intel_context_is_pinned(ce))
> > > > + guc_cancel_context_requests(ce);
> > > > +
> > > > + guc_cancel_sched_engine_requests(guc->sched_engine);
> > > > +
> > > > + /* GuC is blown away, drop all references to contexts */
> > > > + xa_destroy(&guc->context_lookup);
> > > > +}
> > > > +
> > > > +void intel_guc_submission_reset_finish(struct intel_guc *guc)
> > > > +{
> > > > + /* Reset called during driver load or during wedge? */
> > > > + if (unlikely(!guc_submission_initialized(guc) ||
> > > > + test_bit(I915_WEDGED, &guc_to_gt(guc)->reset.flags)))
> > > > + return;
> > > > - ENGINE_TRACE(engine, "depth->%d\n",
> > > > - atomic_read(&sched_engine->tasklet.count));
> > > > + /*
> > > > + * Technically possible for either of these values to be non-zero here,
> > > > + * but very unlikely + harmless. Regardless let's add a warn so we can
> > > > + * see in CI if this happens frequently / a precursor to taking down the
> > > > + * machine.
> > >
> > > And what did CI say over time this was in?
> > >
> >
> > It hasn't popped yet. This is more for upcoming code where we have a
> > g2hs we can't scrub (i.e. a TLB invalidation, engine class scheduling
> > disable, etc...).
> >
> > > It needs to be explained when it can be non zero and whether or not it can
> > > go to non zero just after the atomic_set below. Or if not why not.
> > >
> >
> > At this point we could probably turn this into a BUG_ON.
> >
> > > > + */
> > > > + GEM_WARN_ON(atomic_read(&guc->outstanding_submission_g2h));
> > > > + atomic_set(&guc->outstanding_submission_g2h, 0);
> > > > +
> > > > + enable_submission(guc);
> > > > }
> > > > /*
> > > > @@ -659,6 +955,9 @@ static int guc_bypass_tasklet_submit(struct intel_guc *guc,
> > > > else
> > > > trace_i915_request_guc_submit(rq);
> > > > + if (unlikely(ret == -EDEADLK))
> > > > + disable_submission(guc);
> > > > +
> > > > return ret;
> > > > }
> > > > @@ -671,7 +970,8 @@ static void guc_submit_request(struct i915_request *rq)
> > > > /* Will be called from irq-context when using foreign fences. */
> > > > spin_lock_irqsave(&sched_engine->lock, flags);
> > > > - if (guc->stalled_request || !i915_sched_engine_is_empty(sched_engine))
> > > > + if (submission_disabled(guc) || guc->stalled_request ||
> > > > + !i915_sched_engine_is_empty(sched_engine))
> > > > queue_request(sched_engine, rq, rq_prio(rq));
> > > > else if (guc_bypass_tasklet_submit(guc, rq) == -EBUSY)
> > > > i915_sched_engine_hi_kick(sched_engine);
> > > > @@ -808,7 +1108,8 @@ static void unpin_guc_id(struct intel_guc *guc, struct intel_context *ce)
> > > > static int __guc_action_register_context(struct intel_guc *guc,
> > > > u32 guc_id,
> > > > - u32 offset)
> > > > + u32 offset,
> > > > + bool loop)
> > > > {
> > > > u32 action[] = {
> > > > INTEL_GUC_ACTION_REGISTER_CONTEXT,
> > > > @@ -816,10 +1117,10 @@ static int __guc_action_register_context(struct intel_guc *guc,
> > > > offset,
> > > > };
> > > > - return guc_submission_busy_loop(guc, action, ARRAY_SIZE(action), 0, true);
> > > > + return guc_submission_busy_loop(guc, action, ARRAY_SIZE(action), 0, loop);
> > > > }
> > > > -static int register_context(struct intel_context *ce)
> > > > +static int register_context(struct intel_context *ce, bool loop)
> > > > {
> > > > struct intel_guc *guc = ce_to_guc(ce);
> > > > u32 offset = intel_guc_ggtt_offset(guc, guc->lrc_desc_pool) +
> > > > @@ -827,11 +1128,12 @@ static int register_context(struct intel_context *ce)
> > > > trace_intel_context_register(ce);
> > > > - return __guc_action_register_context(guc, ce->guc_id, offset);
> > > > + return __guc_action_register_context(guc, ce->guc_id, offset, loop);
> > > > }
> > > > static int __guc_action_deregister_context(struct intel_guc *guc,
> > > > - u32 guc_id)
> > > > + u32 guc_id,
> > > > + bool loop)
> > > > {
> > > > u32 action[] = {
> > > > INTEL_GUC_ACTION_DEREGISTER_CONTEXT,
> > > > @@ -839,16 +1141,16 @@ static int __guc_action_deregister_context(struct intel_guc *guc,
> > > > };
> > > > return guc_submission_busy_loop(guc, action, ARRAY_SIZE(action),
> > > > - G2H_LEN_DW_DEREGISTER_CONTEXT, true);
> > > > + G2H_LEN_DW_DEREGISTER_CONTEXT, loop);
> > > > }
> > > > -static int deregister_context(struct intel_context *ce, u32 guc_id)
> > > > +static int deregister_context(struct intel_context *ce, u32 guc_id, bool loop)
> > > > {
> > > > struct intel_guc *guc = ce_to_guc(ce);
> > > > trace_intel_context_deregister(ce);
> > > > - return __guc_action_deregister_context(guc, guc_id);
> > > > + return __guc_action_deregister_context(guc, guc_id, loop);
> > > > }
> > > > static intel_engine_mask_t adjust_engine_mask(u8 class, intel_engine_mask_t mask)
> > > > @@ -877,7 +1179,7 @@ static void guc_context_policy_init(struct intel_engine_cs *engine,
> > > > desc->preemption_timeout = CONTEXT_POLICY_DEFAULT_PREEMPTION_TIME_US;
> > > > }
> > > > -static int guc_lrc_desc_pin(struct intel_context *ce)
> > > > +static int guc_lrc_desc_pin(struct intel_context *ce, bool loop)
> > > > {
> > > > struct intel_runtime_pm *runtime_pm =
> > > > &ce->engine->gt->i915->runtime_pm;
> > > > @@ -923,18 +1225,44 @@ static int guc_lrc_desc_pin(struct intel_context *ce)
> > > > */
> > > > if (context_registered) {
> > > > trace_intel_context_steal_guc_id(ce);
> > > > - set_context_wait_for_deregister_to_register(ce);
> > > > - intel_context_get(ce);
> > > > + if (!loop) {
> > > > + set_context_wait_for_deregister_to_register(ce);
> > > > + intel_context_get(ce);
> > > > + } else {
> > > > + bool disabled;
> > > > + unsigned long flags;
> > > > +
> > > > + /* Seal race with Reset */
> > >
> > > Needs to be more descriptive.
> > >
> >
> > Again have comment about this the doc patch. Basically this goes back to
> > your other questions about cycling a lock. You must check if
> > submission_disabled() within a lock otherwise there is a race with
> > resets and updating a contexts state.
> >
> > > > + spin_lock_irqsave(&ce->guc_state.lock, flags);
> > > > + disabled = submission_disabled(guc);
> > > > + if (likely(!disabled)) {
> > > > + set_context_wait_for_deregister_to_register(ce);
> > > > + intel_context_get(ce);
> > > > + }
> > > > + spin_unlock_irqrestore(&ce->guc_state.lock, flags);
> > > > + if (unlikely(disabled)) {
> > > > + reset_lrc_desc(guc, desc_idx);
> > > > + return 0; /* Will get registered later */
> > > > + }
> > > > + }
> > > > /*
> > > > * If stealing the guc_id, this ce has the same guc_id as the
> > > > * context whos guc_id was stole.
> > > > */
> > > > with_intel_runtime_pm(runtime_pm, wakeref)
> > > > - ret = deregister_context(ce, ce->guc_id);
> > > > + ret = deregister_context(ce, ce->guc_id, loop);
> > > > + if (unlikely(ret == -EBUSY)) {
> > > > + clr_context_wait_for_deregister_to_register(ce);
> > > > + intel_context_put(ce);
> > > > + }
> > > > } else {
> > > > with_intel_runtime_pm(runtime_pm, wakeref)
> > > > - ret = register_context(ce);
> > > > + ret = register_context(ce, loop);
> > > > + if (unlikely(ret == -EBUSY))
> > > > + reset_lrc_desc(guc, desc_idx);
> > > > + else if (unlikely(ret == -ENODEV))
> > > > + ret = 0; /* Will get registered later */
> > > > }
> > > > return ret;
> > > > @@ -997,7 +1325,6 @@ static void __guc_context_sched_disable(struct intel_guc *guc,
> > > > GEM_BUG_ON(guc_id == GUC_INVALID_LRC_ID);
> > > > trace_intel_context_sched_disable(ce);
> > > > - intel_context_get(ce);
> > > > guc_submission_busy_loop(guc, action, ARRAY_SIZE(action),
> > > > G2H_LEN_DW_SCHED_CONTEXT_MODE_SET, true);
> > > > @@ -1007,6 +1334,7 @@ static u16 prep_context_pending_disable(struct intel_context *ce)
> > > > {
> > > > set_context_pending_disable(ce);
> > > > clr_context_enabled(ce);
> > > > + intel_context_get(ce);
> > > > return ce->guc_id;
> > > > }
> > > > @@ -1019,7 +1347,7 @@ static void guc_context_sched_disable(struct intel_context *ce)
> > > > u16 guc_id;
> > > > intel_wakeref_t wakeref;
> > > > - if (context_guc_id_invalid(ce) ||
> > > > + if (submission_disabled(guc) || context_guc_id_invalid(ce) ||
> > > > !lrc_desc_registered(guc, ce->guc_id)) {
> > > > clr_context_enabled(ce);
> > > > goto unpin;
> > > > @@ -1053,19 +1381,13 @@ static void guc_context_sched_disable(struct intel_context *ce)
> > > > static inline void guc_lrc_desc_unpin(struct intel_context *ce)
> > > > {
> > > > - struct intel_engine_cs *engine = ce->engine;
> > > > - struct intel_guc *guc = &engine->gt->uc.guc;
> > > > - unsigned long flags;
> > > > + struct intel_guc *guc = ce_to_guc(ce);
> > > > GEM_BUG_ON(!lrc_desc_registered(guc, ce->guc_id));
> > > > GEM_BUG_ON(ce != __get_context(guc, ce->guc_id));
> > > > GEM_BUG_ON(context_enabled(ce));
> > > > - spin_lock_irqsave(&ce->guc_state.lock, flags);
> > > > - set_context_destroyed(ce);
> > > > - spin_unlock_irqrestore(&ce->guc_state.lock, flags);
> > > > -
> > > > - deregister_context(ce, ce->guc_id);
> > > > + deregister_context(ce, ce->guc_id, true);
> > > > }
> > > > static void __guc_context_destroy(struct intel_context *ce)
> > > > @@ -1093,13 +1415,15 @@ static void guc_context_destroy(struct kref *kref)
> > > > struct intel_guc *guc = &ce->engine->gt->uc.guc;
> > > > intel_wakeref_t wakeref;
> > > > unsigned long flags;
> > > > + bool disabled;
> > > > /*
> > > > * If the guc_id is invalid this context has been stolen and we can free
> > > > * it immediately. Also can be freed immediately if the context is not
> > > > * registered with the GuC.
> > > > */
> > > > - if (context_guc_id_invalid(ce) ||
> > > > + if (submission_disabled(guc) ||
> > > > + context_guc_id_invalid(ce) ||
> > > > !lrc_desc_registered(guc, ce->guc_id)) {
> > > > release_guc_id(guc, ce);
> > > > __guc_context_destroy(ce);
> > > > @@ -1126,6 +1450,18 @@ static void guc_context_destroy(struct kref *kref)
> > > > list_del_init(&ce->guc_id_link);
> > > > spin_unlock_irqrestore(&guc->contexts_lock, flags);
> > > > + /* Seal race with Reset */
> > > > + spin_lock_irqsave(&ce->guc_state.lock, flags);
> > > > + disabled = submission_disabled(guc);
> > > > + if (likely(!disabled))
> > > > + set_context_destroyed(ce);
> > > > + spin_unlock_irqrestore(&ce->guc_state.lock, flags);
> > > > + if (unlikely(disabled)) {
> > > > + release_guc_id(guc, ce);
> > > > + __guc_context_destroy(ce);
> > > > + return;
> > >
> > > Same as above, needs a better comment. It is also hard for reader to know if
> > > snapshot of disabled taked under the lock is still valid after the lock has
> > > been released and why.
> > >
> >
> > Will pull in the doc comment into this patch.
> >
> > Matt
> >
> > > Regards,
> > >
> > > Tvrtko
> > >
> > > > + }
> > > > +
> > > > /*
> > > > * We defer GuC context deregistration until the context is destroyed
> > > > * in order to save on CTBs. With this optimization ideally we only need
> > > > @@ -1148,6 +1484,33 @@ static int guc_context_alloc(struct intel_context *ce)
> > > > return lrc_alloc(ce, ce->engine);
> > > > }
> > > > +static void add_to_context(struct i915_request *rq)
> > > > +{
> > > > + struct intel_context *ce = rq->context;
> > > > +
> > > > + spin_lock(&ce->guc_active.lock);
> > > > + list_move_tail(&rq->sched.link, &ce->guc_active.requests);
> > > > + spin_unlock(&ce->guc_active.lock);
> > > > +}
> > > > +
> > > > +static void remove_from_context(struct i915_request *rq)
> > > > +{
> > > > + struct intel_context *ce = rq->context;
> > > > +
> > > > + spin_lock_irq(&ce->guc_active.lock);
> > > > +
> > > > + list_del_init(&rq->sched.link);
> > > > + clear_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags);
> > > > +
> > > > + /* Prevent further __await_execution() registering a cb, then flush */
> > > > + set_bit(I915_FENCE_FLAG_ACTIVE, &rq->fence.flags);
> > > > +
> > > > + spin_unlock_irq(&ce->guc_active.lock);
> > > > +
> > > > + atomic_dec(&ce->guc_id_ref);
> > > > + i915_request_notify_execute_cb_imm(rq);
> > > > +}
> > > > +
> > > > static const struct intel_context_ops guc_context_ops = {
> > > > .alloc = guc_context_alloc,
> > > > @@ -1186,8 +1549,6 @@ static void guc_signal_context_fence(struct intel_context *ce)
> > > > {
> > > > unsigned long flags;
> > > > - GEM_BUG_ON(!context_wait_for_deregister_to_register(ce));
> > > > -
> > > > spin_lock_irqsave(&ce->guc_state.lock, flags);
> > > > clr_context_wait_for_deregister_to_register(ce);
> > > > __guc_signal_context_fence(ce);
> > > > @@ -1196,8 +1557,9 @@ static void guc_signal_context_fence(struct intel_context *ce)
> > > > static bool context_needs_register(struct intel_context *ce, bool new_guc_id)
> > > > {
> > > > - return new_guc_id || test_bit(CONTEXT_LRCA_DIRTY, &ce->flags) ||
> > > > - !lrc_desc_registered(ce_to_guc(ce), ce->guc_id);
> > > > + return (new_guc_id || test_bit(CONTEXT_LRCA_DIRTY, &ce->flags) ||
> > > > + !lrc_desc_registered(ce_to_guc(ce), ce->guc_id)) &&
> > > > + !submission_disabled(ce_to_guc(ce));
> > > > }
> > > > static int guc_request_alloc(struct i915_request *rq)
> > > > @@ -1256,8 +1618,10 @@ static int guc_request_alloc(struct i915_request *rq)
> > > > return ret;;
> > > > if (context_needs_register(ce, !!ret)) {
> > > > - ret = guc_lrc_desc_pin(ce);
> > > > + ret = guc_lrc_desc_pin(ce, true);
> > > > if (unlikely(ret)) { /* unwind */
> > > > + if (ret == -EDEADLK)
> > > > + disable_submission(guc);
> > > > atomic_dec(&ce->guc_id_ref);
> > > > unpin_guc_id(guc, ce);
> > > > return ret;
> > > > @@ -1294,20 +1658,6 @@ static int guc_request_alloc(struct i915_request *rq)
> > > > return 0;
> > > > }
> > > > -static struct intel_engine_cs *
> > > > -guc_virtual_get_sibling(struct intel_engine_cs *ve, unsigned int sibling)
> > > > -{
> > > > - struct intel_engine_cs *engine;
> > > > - intel_engine_mask_t tmp, mask = ve->mask;
> > > > - unsigned int num_siblings = 0;
> > > > -
> > > > - for_each_engine_masked(engine, ve->gt, mask, tmp)
> > > > - if (num_siblings++ == sibling)
> > > > - return engine;
> > > > -
> > > > - return NULL;
> > > > -}
> > > > -
> > > > static int guc_virtual_context_pre_pin(struct intel_context *ce,
> > > > struct i915_gem_ww_ctx *ww,
> > > > void **vaddr)
> > > > @@ -1516,7 +1866,7 @@ static inline void guc_kernel_context_pin(struct intel_guc *guc,
> > > > {
> > > > if (context_guc_id_invalid(ce))
> > > > pin_guc_id(guc, ce);
> > > > - guc_lrc_desc_pin(ce);
> > > > + guc_lrc_desc_pin(ce, true);
> > > > }
> > > > static inline void guc_init_lrc_mapping(struct intel_guc *guc)
> > > > @@ -1582,13 +1932,15 @@ static void guc_default_vfuncs(struct intel_engine_cs *engine)
> > > > engine->cops = &guc_context_ops;
> > > > engine->request_alloc = guc_request_alloc;
> > > > engine->bump_serial = guc_bump_serial;
> > > > + engine->add_active_request = add_to_context;
> > > > + engine->remove_active_request = remove_from_context;
> > > > engine->sched_engine->schedule = i915_schedule;
> > > > - engine->reset.prepare = guc_reset_prepare;
> > > > - engine->reset.rewind = guc_reset_rewind;
> > > > - engine->reset.cancel = guc_reset_cancel;
> > > > - engine->reset.finish = guc_reset_finish;
> > > > + engine->reset.prepare = guc_reset_nop;
> > > > + engine->reset.rewind = guc_rewind_nop;
> > > > + engine->reset.cancel = guc_reset_nop;
> > > > + engine->reset.finish = guc_reset_nop;
> > > > engine->emit_flush = gen8_emit_flush_xcs;
> > > > engine->emit_init_breadcrumb = gen8_emit_init_breadcrumb;
> > > > @@ -1764,7 +2116,7 @@ int intel_guc_deregister_done_process_msg(struct intel_guc *guc,
> > > > * register this context.
> > > > */
> > > > with_intel_runtime_pm(runtime_pm, wakeref)
> > > > - register_context(ce);
> > > > + register_context(ce, true);
> > > > guc_signal_context_fence(ce);
> > > > intel_context_put(ce);
> > > > } else if (context_destroyed(ce)) {
> > > > @@ -1946,6 +2298,10 @@ guc_create_virtual(struct intel_engine_cs **siblings, unsigned int count)
> > > > "v%dx%d", ve->base.class, count);
> > > > ve->base.context_size = sibling->context_size;
> > > > + ve->base.add_active_request =
> > > > + sibling->add_active_request;
> > > > + ve->base.remove_active_request =
> > > > + sibling->remove_active_request;
> > > > ve->base.emit_bb_start = sibling->emit_bb_start;
> > > > ve->base.emit_flush = sibling->emit_flush;
> > > > ve->base.emit_init_breadcrumb =
> > > > diff --git a/drivers/gpu/drm/i915/gt/uc/intel_uc.c b/drivers/gpu/drm/i915/gt/uc/intel_uc.c
> > > > index ab0789d66e06..d5ccffbb89ae 100644
> > > > --- a/drivers/gpu/drm/i915/gt/uc/intel_uc.c
> > > > +++ b/drivers/gpu/drm/i915/gt/uc/intel_uc.c
> > > > @@ -565,12 +565,44 @@ void intel_uc_reset_prepare(struct intel_uc *uc)
> > > > {
> > > > struct intel_guc *guc = &uc->guc;
> > > > + /* Firmware expected to be running when this function is called */
> > > > if (!intel_guc_is_ready(guc))
> > > > - return;
> > > > + goto sanitize;
> > > > +
> > > > + if (intel_uc_uses_guc_submission(uc))
> > > > + intel_guc_submission_reset_prepare(guc);
> > > > +sanitize:
> > > > __uc_sanitize(uc);
> > > > }
> > > > +void intel_uc_reset(struct intel_uc *uc, bool stalled)
> > > > +{
> > > > + struct intel_guc *guc = &uc->guc;
> > > > +
> > > > + /* Firmware can not be running when this function is called */
> > > > + if (intel_uc_uses_guc_submission(uc))
> > > > + intel_guc_submission_reset(guc, stalled);
> > > > +}
> > > > +
> > > > +void intel_uc_reset_finish(struct intel_uc *uc)
> > > > +{
> > > > + struct intel_guc *guc = &uc->guc;
> > > > +
> > > > + /* Firmware expected to be running when this function is called */
> > > > + if (intel_guc_is_fw_running(guc) && intel_uc_uses_guc_submission(uc))
> > > > + intel_guc_submission_reset_finish(guc);
> > > > +}
> > > > +
> > > > +void intel_uc_cancel_requests(struct intel_uc *uc)
> > > > +{
> > > > + struct intel_guc *guc = &uc->guc;
> > > > +
> > > > + /* Firmware can not be running when this function is called */
> > > > + if (intel_uc_uses_guc_submission(uc))
> > > > + intel_guc_submission_cancel_requests(guc);
> > > > +}
> > > > +
> > > > void intel_uc_runtime_suspend(struct intel_uc *uc)
> > > > {
> > > > struct intel_guc *guc = &uc->guc;
> > > > diff --git a/drivers/gpu/drm/i915/gt/uc/intel_uc.h b/drivers/gpu/drm/i915/gt/uc/intel_uc.h
> > > > index c4cef885e984..eaa3202192ac 100644
> > > > --- a/drivers/gpu/drm/i915/gt/uc/intel_uc.h
> > > > +++ b/drivers/gpu/drm/i915/gt/uc/intel_uc.h
> > > > @@ -37,6 +37,9 @@ void intel_uc_driver_late_release(struct intel_uc *uc);
> > > > void intel_uc_driver_remove(struct intel_uc *uc);
> > > > void intel_uc_init_mmio(struct intel_uc *uc);
> > > > void intel_uc_reset_prepare(struct intel_uc *uc);
> > > > +void intel_uc_reset(struct intel_uc *uc, bool stalled);
> > > > +void intel_uc_reset_finish(struct intel_uc *uc);
> > > > +void intel_uc_cancel_requests(struct intel_uc *uc);
> > > > void intel_uc_suspend(struct intel_uc *uc);
> > > > void intel_uc_runtime_suspend(struct intel_uc *uc);
> > > > int intel_uc_resume(struct intel_uc *uc);
> > > > diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
> > > > index 0b96b824ea06..4855cf7ebe21 100644
> > > > --- a/drivers/gpu/drm/i915/i915_request.c
> > > > +++ b/drivers/gpu/drm/i915/i915_request.c
> > > > @@ -194,7 +194,7 @@ static bool irq_work_imm(struct irq_work *wrk)
> > > > return false;
> > > > }
> > > > -static void __notify_execute_cb_imm(struct i915_request *rq)
> > > > +void i915_request_notify_execute_cb_imm(struct i915_request *rq)
> > > > {
> > > > __notify_execute_cb(rq, irq_work_imm);
> > > > }
> > > > @@ -268,37 +268,6 @@ i915_request_active_engine(struct i915_request *rq,
> > > > return ret;
> > > > }
> > > > -
> > > > -static void remove_from_engine(struct i915_request *rq)
> > > > -{
> > > > - struct intel_engine_cs *engine, *locked;
> > > > -
> > > > - /*
> > > > - * Virtual engines complicate acquiring the engine timeline lock,
> > > > - * as their rq->engine pointer is not stable until under that
> > > > - * engine lock. The simple ploy we use is to take the lock then
> > > > - * check that the rq still belongs to the newly locked engine.
> > > > - */
> > > > - locked = READ_ONCE(rq->engine);
> > > > - spin_lock_irq(&locked->sched_engine->lock);
> > > > - while (unlikely(locked != (engine = READ_ONCE(rq->engine)))) {
> > > > - spin_unlock(&locked->sched_engine->lock);
> > > > - spin_lock(&engine->sched_engine->lock);
> > > > - locked = engine;
> > > > - }
> > > > - list_del_init(&rq->sched.link);
> > > > -
> > > > - clear_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags);
> > > > - clear_bit(I915_FENCE_FLAG_HOLD, &rq->fence.flags);
> > > > -
> > > > - /* Prevent further __await_execution() registering a cb, then flush */
> > > > - set_bit(I915_FENCE_FLAG_ACTIVE, &rq->fence.flags);
> > > > -
> > > > - spin_unlock_irq(&locked->sched_engine->lock);
> > > > -
> > > > - __notify_execute_cb_imm(rq);
> > > > -}
> > > > -
> > > > static void __rq_init_watchdog(struct i915_request *rq)
> > > > {
> > > > rq->watchdog.timer.function = NULL;
> > > > @@ -395,9 +364,7 @@ bool i915_request_retire(struct i915_request *rq)
> > > > * after removing the breadcrumb and signaling it, so that we do not
> > > > * inadvertently attach the breadcrumb to a completed request.
> > > > */
> > > > - if (!list_empty(&rq->sched.link))
> > > > - remove_from_engine(rq);
> > > > - atomic_dec(&rq->context->guc_id_ref);
> > > > + rq->engine->remove_active_request(rq);
> > > > GEM_BUG_ON(!llist_empty(&rq->execute_cb));
> > > > __list_del_entry(&rq->link); /* poison neither prev/next (RCU walks) */
> > > > @@ -539,7 +506,7 @@ __await_execution(struct i915_request *rq,
> > > > if (llist_add(&cb->work.node.llist, &signal->execute_cb)) {
> > > > if (i915_request_is_active(signal) ||
> > > > __request_in_flight(signal))
> > > > - __notify_execute_cb_imm(signal);
> > > > + i915_request_notify_execute_cb_imm(signal);
> > > > }
> > > > return 0;
> > > > @@ -676,7 +643,7 @@ bool __i915_request_submit(struct i915_request *request)
> > > > result = true;
> > > > GEM_BUG_ON(test_bit(I915_FENCE_FLAG_ACTIVE, &request->fence.flags));
> > > > - list_move_tail(&request->sched.link, &engine->sched_engine->requests);
> > > > + engine->add_active_request(request);
> > > > active:
> > > > clear_bit(I915_FENCE_FLAG_PQUEUE, &request->fence.flags);
> > > > set_bit(I915_FENCE_FLAG_ACTIVE, &request->fence.flags);
> > > > diff --git a/drivers/gpu/drm/i915/i915_request.h b/drivers/gpu/drm/i915/i915_request.h
> > > > index f870cd75a001..bcc6340c505e 100644
> > > > --- a/drivers/gpu/drm/i915/i915_request.h
> > > > +++ b/drivers/gpu/drm/i915/i915_request.h
> > > > @@ -649,4 +649,6 @@ bool
> > > > i915_request_active_engine(struct i915_request *rq,
> > > > struct intel_engine_cs **active);
> > > > +void i915_request_notify_execute_cb_imm(struct i915_request *rq);
> > > > +
> > > > #endif /* I915_REQUEST_H */
> > > >
> > _______________________________________________
> > Intel-gfx mailing list
> > Intel-gfx at lists.freedesktop.org
> > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
>
>
>
> --
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch
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