On Mon, Jul 12, 2021 at 12:58:45PM -0700, John Harrison wrote:
> On 6/24/2021 00:05, 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.
> There seems to be quite a lot more code being changed in the patch than is
> described above. Sure, it's all in order to support resets but there is a
> lot happening to request/context management, support for GuC submission
> enable/disable, etc. It feels like this patch really should be split into a
> couple of prep patches followed by the actual reset support. Plus see couple
> of minor comments below.
>
Yea, this is probably the most churned on patch we have as getting
resets to full work isn't easy. I'll fix the below comments but I don't
know if it worth spliting. Everything in the patch is required to get
resets to work and I think it is better to have in a single patch so
'git blame' can give you the whole picture.
Matt
> > Cc: John Harrison <john.c.harrison@xxxxxxxxx>
> > Signed-off-by: Matthew Brost <matthew.brost@xxxxxxxxx>
> > ---
> > 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 | 13 -
> > drivers/gpu/drm/i915/gt/uc/intel_guc.h | 8 +-
> > .../gpu/drm/i915/gt/uc/intel_guc_submission.c | 581 ++++++++++++++----
> > drivers/gpu/drm/i915/gt/uc/intel_uc.c | 39 +-
> > 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, 649 insertions(+), 171 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;
> > +
> > /* 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 e7cb6a06db9d..f9d264c008e8 100644
> > --- a/drivers/gpu/drm/i915/gt/intel_engine_types.h
> > +++ b/drivers/gpu/drm/i915/gt/intel_engine_types.h
> > @@ -426,6 +426,12 @@ 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 c10ea6080752..c301a2d088b1 100644
> > --- a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
> > +++ b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
> > @@ -3118,6 +3118,42 @@ 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;
> > + }
> > + 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 (GRAPHICS_VER(engine->i915) > 8)
> > @@ -3218,6 +3254,8 @@ 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;
> > @@ -3912,6 +3950,8 @@ execlists_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 = 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 72251638d4ea..2987282dff6d 100644
> > --- a/drivers/gpu/drm/i915/gt/intel_reset.c
> > +++ b/drivers/gpu/drm/i915/gt/intel_reset.c
> > @@ -826,6 +826,8 @@ 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;
> > @@ -850,6 +852,8 @@ 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)
> > @@ -903,6 +907,7 @@ 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);
> > @@ -1191,6 +1196,9 @@ 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;
> > @@ -1201,13 +1209,10 @@ 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;
> > }
> > @@ -1341,7 +1346,8 @@ 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)) {
> > 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 e1506b280df1..99dcdc8fba12 100644
> > --- a/drivers/gpu/drm/i915/gt/intel_ring_submission.c
> > +++ b/drivers/gpu/drm/i915/gt/intel_ring_submission.c
> > @@ -1049,6 +1049,25 @@ 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;
> > @@ -1066,6 +1085,9 @@ 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 fc5a65ab1937..c12ff3a75ce6 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 6661dcb02239..9b09395b998f 100644
> > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc.c
> > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.c
> > @@ -572,19 +572,6 @@ 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 22eb1e9cca41..40c9868762d7 100644
> > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc.h
> > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.h
> > @@ -242,14 +242,16 @@ 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 83058df5ba01..b8c894ad8caf 100644
> > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
> > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
> > @@ -141,7 +141,7 @@ 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;
> > }
> > @@ -241,15 +241,31 @@ 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)
> > @@ -260,7 +276,15 @@ 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,
> > @@ -331,6 +355,8 @@ 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;
> > @@ -338,11 +364,22 @@ 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;
> > @@ -365,6 +402,7 @@ static int guc_add_request(struct intel_guc *guc, struct i915_request *rq)
> > intel_context_put(ce);
> > }
> > +out:
> > return err;
> > }
> > @@ -419,15 +457,10 @@ 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 == -EIO))
> > + goto deadlk;
> > + else if (ret == -EBUSY) {
> > tasklet_schedule(&sched_engine->tasklet);
> > guc->stalled_request = last;
> > return false;
> > @@ -437,6 +470,11 @@ 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)
> > @@ -463,27 +501,165 @@ 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 intel_context *ce;
> > + unsigned long index, flags;
> > + bool pending_disable, pending_enable, deregister, destroyed;
> > +
> > + 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);
> > +
> > + /*
> > + * Once we are at this point submission_disabled() is guaranteed
> > + * to visible to all callers who set the below flags (see above
> to be visible
>
> > + * 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);
> > + }
> > + }
> > +}
> > +
> > +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();
> > + 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. */
> > + tasklet_hi_schedule(&sched_engine->tasklet);
> > + }
> > + spin_unlock_irqrestore(&guc->sched_engine->lock, flags);
> > +}
> > +
> > +static void guc_flush_submissions(struct intel_guc *guc)
> > {
> > - ENGINE_TRACE(engine, "\n");
> > + 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);
> > +}
> > +
> > +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;
> Ew. Multi-line if without braces just looks broken even if one line is just
> a comment.
>
> > +
> > + 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 execlists->tasklet *just* as we are
> > - * calling engine->init_hw() and also writing the ELSP.
> > - * Turning off the execlists->tasklet until the reset is over
> > - * prevents the race.
> > - */
> > - __tasklet_disable_sync_once(&engine->sched_engine->tasklet);
> > + * 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.
> > + */
> > + for (i = 0; i < 4 && atomic_read(&guc->outstanding_submission_g2h); ++i) {
> > + 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 void guc_reset_state(struct intel_context *ce,
> > - struct intel_engine_cs *engine,
> > - u32 head,
> > - bool scrub)
> > +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 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, u32 head, bool scrub)
> > +{
> > + struct intel_engine_cs *engine = __context_to_physical_engine(ce);
> > +
> > GEM_BUG_ON(!intel_context_is_pinned(ce));
> > /*
> > @@ -501,42 +677,147 @@ 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);
> > +
> > + __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));
> > +
> > + list_add_tail(&rq->sched.link, pl);
> > + set_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags);
> > - /* Push back any incomplete requests for replay after the reset. */
> > - rq = execlists_unwind_incomplete_requests(execlists);
> > - if (!rq)
> > - goto out_unlock;
> > + 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);
> > }
> > -static void guc_reset_cancel(struct intel_engine_cs *engine)
> > +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;
> And again.
>
> > +
> > + 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);
> > +}
> > +
> > +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
> > @@ -553,21 +834,16 @@ static void guc_reset_cancel(struct intel_engine_cs *engine)
> > */
> > spin_lock_irqsave(&sched_engine->lock, flags);
> > - /* Mark all executing requests as skipped. */
> > - list_for_each_entry(rq, &sched_engine->requests, sched.link) {
> > - i915_request_set_error_once(rq, -EIO);
> > - i915_request_mark_complete(rq);
> > - }
> > -
> > /* Flush the queued requests to the timeline list (for retiring). */
> > while ((rb = rb_first_cached(&sched_engine->queue))) {
> > struct i915_priolist *p = to_priolist(rb);
> > 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);
> > @@ -582,14 +858,38 @@ static void guc_reset_cancel(struct intel_engine_cs *engine)
> > 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)
> > {
> > - if (__tasklet_enable(&engine->sched_engine->tasklet))
> > - /* And kick in case we missed a new request submission. */
> > - tasklet_hi_schedule(&engine->sched_engine->tasklet);
> > + struct intel_context *ce;
> > + unsigned long index;
> > +
> > + xa_for_each(&guc->context_lookup, index, ce)
> > + if (intel_context_is_pinned(ce))
> > + guc_cancel_context_requests(ce);
> > - ENGINE_TRACE(engine, "depth->%d\n",
> > - atomic_read(&engine->sched_engine->tasklet.count));
> > + guc_cancel_sched_engine_requests(guc->sched_engine);
> > +
> > + /* GuC is blown away, drop all references to contexts */
> > + xa_destroy(&guc->context_lookup);
> This function shares most of the code with 'intel_guc_submission_reset'. Can
> the xa clean be moved to a common helper?
>
> John.
>
> > +}
> > +
> > +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;
> > +
> > + /*
> > + * 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.
> > + */
> > + GEM_WARN_ON(atomic_read(&guc->outstanding_submission_g2h));
> > + atomic_set(&guc->outstanding_submission_g2h, 0);
> > +
> > + enable_submission(guc);
> > }
> > /*
> > @@ -656,6 +956,9 @@ static int guc_bypass_tasklet_submit(struct intel_guc *guc,
> > else
> > trace_i915_request_guc_submit(rq);
> > + if (unlikely(ret == -EIO))
> > + disable_submission(guc);
> > +
> > return ret;
> > }
> > @@ -668,7 +971,8 @@ 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)
> > tasklet_hi_schedule(&sched_engine->tasklet);
> > @@ -805,7 +1109,8 @@ 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,
> > @@ -813,10 +1118,10 @@ 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) +
> > @@ -824,11 +1129,12 @@ 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,
> > @@ -836,16 +1142,16 @@ 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)
> > @@ -874,7 +1180,7 @@ 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;
> > @@ -920,18 +1226,44 @@ 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 */
> > + 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;
> > @@ -994,7 +1326,6 @@ 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);
> > @@ -1004,6 +1335,7 @@ 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;
> > }
> > @@ -1016,7 +1348,7 @@ 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;
> > @@ -1034,6 +1366,7 @@ static void guc_context_sched_disable(struct intel_context *ce)
> > * request doesn't slip through the 'context_pending_disable' fence.
> > */
> > if (unlikely(atomic_add_unless(&ce->pin_count, -2, 2))) {
> > + spin_unlock_irqrestore(&ce->guc_state.lock, flags);
> > return;
> > }
> > guc_id = prep_context_pending_disable(ce);
> > @@ -1050,19 +1383,13 @@ 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)
> > @@ -1090,13 +1417,15 @@ 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);
> > @@ -1123,6 +1452,18 @@ 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;
> > + }
> > +
> > /*
> > * We defer GuC context deregistration until the context is destroyed
> > * in order to save on CTBs. With this optimization ideally we only need
> > @@ -1145,6 +1486,33 @@ 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,
> > @@ -1183,8 +1551,6 @@ 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);
> > @@ -1193,8 +1559,9 @@ 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)
> > @@ -1252,8 +1619,12 @@ static int guc_request_alloc(struct i915_request *rq)
> > if (unlikely(ret < 0))
> > 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 == -EIO) {
> > + disable_submission(guc);
> > + goto out; /* GPU will be reset */
> > + }
> > atomic_dec(&ce->guc_id_ref);
> > unpin_guc_id(guc, ce);
> > return ret;
> > @@ -1290,20 +1661,6 @@ 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)
> > @@ -1512,7 +1869,7 @@ 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)
> > @@ -1578,13 +1935,15 @@ 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;
> > @@ -1757,7 +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)) {
> > @@ -1939,6 +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 6d8b9233214e..f0b02200aa01 100644
> > --- a/drivers/gpu/drm/i915/gt/uc/intel_uc.c
> > +++ b/drivers/gpu/drm/i915/gt/uc/intel_uc.c
> > @@ -565,12 +565,49 @@ void intel_uc_reset_prepare(struct intel_uc *uc)
> > {
> > struct intel_guc *guc = &uc->guc;
> > - if (!intel_guc_is_ready(guc))
> > +
> > + /* Nothing to do if GuC isn't supported */
> > + if (!intel_uc_supports_guc(uc))
> > return;
> > + /* Firmware expected to be running when this function is called */
> > + if (!intel_guc_is_ready(guc))
> > + 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 dec5a35c9aa2..192784875a1d 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 */
>
