| Message ID | 20211013204231.19287-3-matthew.brost@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Parallel submission aka multi-bb execbuf | expand |
On 10/13/2021 13:42, Matthew Brost wrote: > Taking a PM reference to prevent intel_gt_wait_for_idle from short > circuiting while a deregister context H2G is in flight. To do this must > issue the deregister H2G from a worker as context can be destroyed from > an atomic context and taking GT PM ref blows up. Previously we took a > runtime PM from this atomic context which worked but will stop working > once runtime pm autosuspend in enabled. > > So this patch is two fold, stop intel_gt_wait_for_idle from short > circuting and fix runtime pm autosuspend. > > v2: > (John Harrison) > - Split structure changes out in different patch > (Tvrtko) > - Don't drop lock in deregister_destroyed_contexts > v3: > (John Harrison) > - Flush destroyed contexts before destroying context reg pool > > Signed-off-by: Matthew Brost <matthew.brost@intel.com> Reviewed-by: John Harrison <John.C.Harrison@Intel.com> > --- > drivers/gpu/drm/i915/gt/intel_context.c | 2 + > drivers/gpu/drm/i915/gt/intel_context_types.h | 7 + > drivers/gpu/drm/i915/gt/intel_engine_pm.h | 5 + > drivers/gpu/drm/i915/gt/intel_gt_pm.h | 4 + > drivers/gpu/drm/i915/gt/uc/intel_guc.h | 11 ++ > .../gpu/drm/i915/gt/uc/intel_guc_submission.c | 146 +++++++++++------- > 6 files changed, 121 insertions(+), 54 deletions(-) > > diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c > index 35babd02ddfe..d008ef8623ce 100644 > --- a/drivers/gpu/drm/i915/gt/intel_context.c > +++ b/drivers/gpu/drm/i915/gt/intel_context.c > @@ -400,6 +400,8 @@ intel_context_init(struct intel_context *ce, struct intel_engine_cs *engine) > ce->guc_id.id = GUC_INVALID_LRC_ID; > INIT_LIST_HEAD(&ce->guc_id.link); > > + INIT_LIST_HEAD(&ce->destroyed_link); > + > /* > * Initialize fence to be complete as this is expected to be complete > * unless there is a pending schedule disable outstanding. > diff --git a/drivers/gpu/drm/i915/gt/intel_context_types.h b/drivers/gpu/drm/i915/gt/intel_context_types.h > index e7e3984aab78..4613d027cbc3 100644 > --- a/drivers/gpu/drm/i915/gt/intel_context_types.h > +++ b/drivers/gpu/drm/i915/gt/intel_context_types.h > @@ -213,6 +213,13 @@ struct intel_context { > struct list_head link; > } guc_id; > > + /** > + * @destroyed_link: link in guc->submission_state.destroyed_contexts, in > + * list when context is pending to be destroyed (deregistered with the > + * GuC), protected by guc->submission_state.lock > + */ > + struct list_head destroyed_link; > + > #ifdef CONFIG_DRM_I915_SELFTEST > /** > * @drop_schedule_enable: Force drop of schedule enable G2H for selftest > diff --git a/drivers/gpu/drm/i915/gt/intel_engine_pm.h b/drivers/gpu/drm/i915/gt/intel_engine_pm.h > index 8520c595f5e1..6fdeae668e6e 100644 > --- a/drivers/gpu/drm/i915/gt/intel_engine_pm.h > +++ b/drivers/gpu/drm/i915/gt/intel_engine_pm.h > @@ -16,6 +16,11 @@ intel_engine_pm_is_awake(const struct intel_engine_cs *engine) > return intel_wakeref_is_active(&engine->wakeref); > } > > +static inline void __intel_engine_pm_get(struct intel_engine_cs *engine) > +{ > + __intel_wakeref_get(&engine->wakeref); > +} > + > static inline void intel_engine_pm_get(struct intel_engine_cs *engine) > { > intel_wakeref_get(&engine->wakeref); > diff --git a/drivers/gpu/drm/i915/gt/intel_gt_pm.h b/drivers/gpu/drm/i915/gt/intel_gt_pm.h > index d0588d8aaa44..05de6c1af25b 100644 > --- a/drivers/gpu/drm/i915/gt/intel_gt_pm.h > +++ b/drivers/gpu/drm/i915/gt/intel_gt_pm.h > @@ -41,6 +41,10 @@ static inline void intel_gt_pm_put_async(struct intel_gt *gt) > intel_wakeref_put_async(>->wakeref); > } > > +#define with_intel_gt_pm(gt, tmp) \ > + for (tmp = 1, intel_gt_pm_get(gt); tmp; \ > + intel_gt_pm_put(gt), tmp = 0) > + > static inline int intel_gt_pm_wait_for_idle(struct intel_gt *gt) > { > return intel_wakeref_wait_for_idle(>->wakeref); > diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc.h b/drivers/gpu/drm/i915/gt/uc/intel_guc.h > index 82e248c2290c..74f071a0b6d5 100644 > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc.h > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.h > @@ -90,6 +90,17 @@ struct intel_guc { > * refs > */ > struct list_head guc_id_list; > + /** > + * @destroyed_contexts: list of contexts waiting to be destroyed > + * (deregistered with the GuC) > + */ > + struct list_head destroyed_contexts; > + /** > + * @destroyed_worker: worker to deregister contexts, need as we > + * need to take a GT PM reference and can't from destroy > + * function as it might be in an atomic context (no sleeping) > + */ > + struct work_struct destroyed_worker; > } submission_state; > > /** > 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 b2646b088c7f..d2ce47b5541e 100644 > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > @@ -90,8 +90,8 @@ > * used for all of GuC submission but that could change in the future. > * > * guc->submission_state.lock > - * Protects guc_id allocation for the given GuC, i.e. only one context can be > - * doing guc_id allocation operations at a time for each GuC in the system. > + * Global lock for GuC submission state. Protects guc_ids and destroyed contexts > + * list. > * > * ce->guc_state.lock > * Protects everything under ce->guc_state. Ensures that a context is in the > @@ -719,6 +719,7 @@ static void scrub_guc_desc_for_outstanding_g2h(struct intel_guc *guc) > if (deregister) > guc_signal_context_fence(ce); > if (destroyed) { > + intel_gt_pm_put_async(guc_to_gt(guc)); > release_guc_id(guc, ce); > __guc_context_destroy(ce); > } > @@ -797,6 +798,8 @@ static void guc_flush_submissions(struct intel_guc *guc) > spin_unlock_irqrestore(&sched_engine->lock, flags); > } > > +static void guc_flush_destroyed_contexts(struct intel_guc *guc); > + > void intel_guc_submission_reset_prepare(struct intel_guc *guc) > { > int i; > @@ -815,6 +818,7 @@ void intel_guc_submission_reset_prepare(struct intel_guc *guc) > spin_unlock_irq(&guc_to_gt(guc)->irq_lock); > > guc_flush_submissions(guc); > + guc_flush_destroyed_contexts(guc); > > /* > * Handle any outstanding G2Hs before reset. Call IRQ handler directly > @@ -1126,6 +1130,8 @@ void intel_guc_submission_reset_finish(struct intel_guc *guc) > intel_gt_unpark_heartbeats(guc_to_gt(guc)); > } > > +static void destroyed_worker_func(struct work_struct *w); > + > /* > * Set up the memory resources to be shared with the GuC (via the GGTT) > * at firmware loading time. > @@ -1151,6 +1157,9 @@ int intel_guc_submission_init(struct intel_guc *guc) > spin_lock_init(&guc->submission_state.lock); > INIT_LIST_HEAD(&guc->submission_state.guc_id_list); > ida_init(&guc->submission_state.guc_ids); > + INIT_LIST_HEAD(&guc->submission_state.destroyed_contexts); > + INIT_WORK(&guc->submission_state.destroyed_worker, > + destroyed_worker_func); > > return 0; > } > @@ -1160,6 +1169,7 @@ void intel_guc_submission_fini(struct intel_guc *guc) > if (!guc->lrc_desc_pool) > return; > > + guc_flush_destroyed_contexts(guc); > guc_lrc_desc_pool_destroy(guc); > i915_sched_engine_put(guc->sched_engine); > } > @@ -1859,11 +1869,30 @@ static void guc_context_sched_disable(struct intel_context *ce) > static inline void guc_lrc_desc_unpin(struct intel_context *ce) > { > struct intel_guc *guc = ce_to_guc(ce); > + struct intel_gt *gt = guc_to_gt(guc); > + unsigned long flags; > + bool disabled; > > + GEM_BUG_ON(!intel_gt_pm_is_awake(gt)); > GEM_BUG_ON(!lrc_desc_registered(guc, ce->guc_id.id)); > GEM_BUG_ON(ce != __get_context(guc, ce->guc_id.id)); > GEM_BUG_ON(context_enabled(ce)); > > + /* Seal race with Reset */ > + spin_lock_irqsave(&ce->guc_state.lock, flags); > + disabled = submission_disabled(guc); > + if (likely(!disabled)) { > + __intel_gt_pm_get(gt); > + set_context_destroyed(ce); > + clr_context_registered(ce); > + } > + spin_unlock_irqrestore(&ce->guc_state.lock, flags); > + if (unlikely(disabled)) { > + release_guc_id(guc, ce); > + __guc_context_destroy(ce); > + return; > + } > + > deregister_context(ce, ce->guc_id.id); > } > > @@ -1891,78 +1920,86 @@ static void __guc_context_destroy(struct intel_context *ce) > } > } > > +static void guc_flush_destroyed_contexts(struct intel_guc *guc) > +{ > + struct intel_context *ce, *cn; > + unsigned long flags; > + > + GEM_BUG_ON(!submission_disabled(guc) && > + guc_submission_initialized(guc)); > + > + spin_lock_irqsave(&guc->submission_state.lock, flags); > + list_for_each_entry_safe(ce, cn, > + &guc->submission_state.destroyed_contexts, > + destroyed_link) { > + list_del_init(&ce->destroyed_link); > + __release_guc_id(guc, ce); > + __guc_context_destroy(ce); > + } > + spin_unlock_irqrestore(&guc->submission_state.lock, flags); > +} > + > +static void deregister_destroyed_contexts(struct intel_guc *guc) > +{ > + struct intel_context *ce, *cn; > + unsigned long flags; > + > + spin_lock_irqsave(&guc->submission_state.lock, flags); > + list_for_each_entry_safe(ce, cn, > + &guc->submission_state.destroyed_contexts, > + destroyed_link) { > + list_del_init(&ce->destroyed_link); > + guc_lrc_desc_unpin(ce); > + } > + spin_unlock_irqrestore(&guc->submission_state.lock, flags); > +} > + > +static void destroyed_worker_func(struct work_struct *w) > +{ > + struct intel_guc *guc = container_of(w, struct intel_guc, > + submission_state.destroyed_worker); > + struct intel_gt *gt = guc_to_gt(guc); > + int tmp; > + > + with_intel_gt_pm(gt, tmp) > + deregister_destroyed_contexts(guc); > +} > + > static void guc_context_destroy(struct kref *kref) > { > struct intel_context *ce = container_of(kref, typeof(*ce), ref); > - struct intel_runtime_pm *runtime_pm = ce->engine->uncore->rpm; > struct intel_guc *guc = ce_to_guc(ce); > - intel_wakeref_t wakeref; > unsigned long flags; > - bool disabled; > + bool destroy; > > /* > * 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 or the GuC is in the middle of a reset. > */ > - if (context_guc_id_invalid(ce)) { > - __guc_context_destroy(ce); > - return; > - } else if (submission_disabled(guc) || > - !lrc_desc_registered(guc, ce->guc_id.id)) { > - release_guc_id(guc, ce); > - __guc_context_destroy(ce); > - return; > - } > - > - /* > - * We have to acquire the context spinlock and check guc_id again, if it > - * is valid it hasn't been stolen and needs to be deregistered. We > - * delete this context from the list of unpinned guc_id available to > - * steal to seal a race with guc_lrc_desc_pin(). When the G2H CTB > - * returns indicating this context has been deregistered the guc_id is > - * returned to the pool of available guc_id. > - */ > spin_lock_irqsave(&guc->submission_state.lock, flags); > - if (context_guc_id_invalid(ce)) { > - spin_unlock_irqrestore(&guc->submission_state.lock, flags); > - __guc_context_destroy(ce); > - return; > + destroy = submission_disabled(guc) || context_guc_id_invalid(ce) || > + !lrc_desc_registered(guc, ce->guc_id.id); > + if (likely(!destroy)) { > + if (!list_empty(&ce->guc_id.link)) > + list_del_init(&ce->guc_id.link); > + list_add_tail(&ce->destroyed_link, > + &guc->submission_state.destroyed_contexts); > + } else { > + __release_guc_id(guc, ce); > } > - > - if (!list_empty(&ce->guc_id.link)) > - list_del_init(&ce->guc_id.link); > spin_unlock_irqrestore(&guc->submission_state.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); > - clr_context_registered(ce); > - } > - spin_unlock_irqrestore(&ce->guc_state.lock, flags); > - if (unlikely(disabled)) { > - release_guc_id(guc, ce); > + if (unlikely(destroy)) { > __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 > - * 1 CTB to register the context during the first pin and 1 CTB to > - * deregister the context when the context is destroyed. Without this > - * optimization, a CTB would be needed every pin & unpin. > - * > - * XXX: Need to acqiure the runtime wakeref as this can be triggered > - * from context_free_worker when runtime wakeref is not held. > - * guc_lrc_desc_unpin requires the runtime as a GuC register is written > - * in H2G CTB to deregister the context. A future patch may defer this > - * H2G CTB if the runtime wakeref is zero. > + * We use a worker to issue the H2G to deregister the context as we can > + * take the GT PM for the first time which isn't allowed from an atomic > + * context. > */ > - with_intel_runtime_pm(runtime_pm, wakeref) > - guc_lrc_desc_unpin(ce); > + queue_work(system_unbound_wq, &guc->submission_state.destroyed_worker); > } > > static int guc_context_alloc(struct intel_context *ce) > @@ -2798,6 +2835,7 @@ int intel_guc_deregister_done_process_msg(struct intel_guc *guc, > intel_context_put(ce); > } else if (context_destroyed(ce)) { > /* Context has been destroyed */ > + intel_gt_pm_put_async(guc_to_gt(guc)); > release_guc_id(guc, ce); > __guc_context_destroy(ce); > }
diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c index 35babd02ddfe..d008ef8623ce 100644 --- a/drivers/gpu/drm/i915/gt/intel_context.c +++ b/drivers/gpu/drm/i915/gt/intel_context.c @@ -400,6 +400,8 @@ intel_context_init(struct intel_context *ce, struct intel_engine_cs *engine) ce->guc_id.id = GUC_INVALID_LRC_ID; INIT_LIST_HEAD(&ce->guc_id.link); + INIT_LIST_HEAD(&ce->destroyed_link); + /* * Initialize fence to be complete as this is expected to be complete * unless there is a pending schedule disable outstanding. diff --git a/drivers/gpu/drm/i915/gt/intel_context_types.h b/drivers/gpu/drm/i915/gt/intel_context_types.h index e7e3984aab78..4613d027cbc3 100644 --- a/drivers/gpu/drm/i915/gt/intel_context_types.h +++ b/drivers/gpu/drm/i915/gt/intel_context_types.h @@ -213,6 +213,13 @@ struct intel_context { struct list_head link; } guc_id; + /** + * @destroyed_link: link in guc->submission_state.destroyed_contexts, in + * list when context is pending to be destroyed (deregistered with the + * GuC), protected by guc->submission_state.lock + */ + struct list_head destroyed_link; + #ifdef CONFIG_DRM_I915_SELFTEST /** * @drop_schedule_enable: Force drop of schedule enable G2H for selftest diff --git a/drivers/gpu/drm/i915/gt/intel_engine_pm.h b/drivers/gpu/drm/i915/gt/intel_engine_pm.h index 8520c595f5e1..6fdeae668e6e 100644 --- a/drivers/gpu/drm/i915/gt/intel_engine_pm.h +++ b/drivers/gpu/drm/i915/gt/intel_engine_pm.h @@ -16,6 +16,11 @@ intel_engine_pm_is_awake(const struct intel_engine_cs *engine) return intel_wakeref_is_active(&engine->wakeref); } +static inline void __intel_engine_pm_get(struct intel_engine_cs *engine) +{ + __intel_wakeref_get(&engine->wakeref); +} + static inline void intel_engine_pm_get(struct intel_engine_cs *engine) { intel_wakeref_get(&engine->wakeref); diff --git a/drivers/gpu/drm/i915/gt/intel_gt_pm.h b/drivers/gpu/drm/i915/gt/intel_gt_pm.h index d0588d8aaa44..05de6c1af25b 100644 --- a/drivers/gpu/drm/i915/gt/intel_gt_pm.h +++ b/drivers/gpu/drm/i915/gt/intel_gt_pm.h @@ -41,6 +41,10 @@ static inline void intel_gt_pm_put_async(struct intel_gt *gt) intel_wakeref_put_async(>->wakeref); } +#define with_intel_gt_pm(gt, tmp) \ + for (tmp = 1, intel_gt_pm_get(gt); tmp; \ + intel_gt_pm_put(gt), tmp = 0) + static inline int intel_gt_pm_wait_for_idle(struct intel_gt *gt) { return intel_wakeref_wait_for_idle(>->wakeref); diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc.h b/drivers/gpu/drm/i915/gt/uc/intel_guc.h index 82e248c2290c..74f071a0b6d5 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc.h +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.h @@ -90,6 +90,17 @@ struct intel_guc { * refs */ struct list_head guc_id_list; + /** + * @destroyed_contexts: list of contexts waiting to be destroyed + * (deregistered with the GuC) + */ + struct list_head destroyed_contexts; + /** + * @destroyed_worker: worker to deregister contexts, need as we + * need to take a GT PM reference and can't from destroy + * function as it might be in an atomic context (no sleeping) + */ + struct work_struct destroyed_worker; } submission_state; /** 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 b2646b088c7f..d2ce47b5541e 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c @@ -90,8 +90,8 @@ * used for all of GuC submission but that could change in the future. * * guc->submission_state.lock - * Protects guc_id allocation for the given GuC, i.e. only one context can be - * doing guc_id allocation operations at a time for each GuC in the system. + * Global lock for GuC submission state. Protects guc_ids and destroyed contexts + * list. * * ce->guc_state.lock * Protects everything under ce->guc_state. Ensures that a context is in the @@ -719,6 +719,7 @@ static void scrub_guc_desc_for_outstanding_g2h(struct intel_guc *guc) if (deregister) guc_signal_context_fence(ce); if (destroyed) { + intel_gt_pm_put_async(guc_to_gt(guc)); release_guc_id(guc, ce); __guc_context_destroy(ce); } @@ -797,6 +798,8 @@ static void guc_flush_submissions(struct intel_guc *guc) spin_unlock_irqrestore(&sched_engine->lock, flags); } +static void guc_flush_destroyed_contexts(struct intel_guc *guc); + void intel_guc_submission_reset_prepare(struct intel_guc *guc) { int i; @@ -815,6 +818,7 @@ void intel_guc_submission_reset_prepare(struct intel_guc *guc) spin_unlock_irq(&guc_to_gt(guc)->irq_lock); guc_flush_submissions(guc); + guc_flush_destroyed_contexts(guc); /* * Handle any outstanding G2Hs before reset. Call IRQ handler directly @@ -1126,6 +1130,8 @@ void intel_guc_submission_reset_finish(struct intel_guc *guc) intel_gt_unpark_heartbeats(guc_to_gt(guc)); } +static void destroyed_worker_func(struct work_struct *w); + /* * Set up the memory resources to be shared with the GuC (via the GGTT) * at firmware loading time. @@ -1151,6 +1157,9 @@ int intel_guc_submission_init(struct intel_guc *guc) spin_lock_init(&guc->submission_state.lock); INIT_LIST_HEAD(&guc->submission_state.guc_id_list); ida_init(&guc->submission_state.guc_ids); + INIT_LIST_HEAD(&guc->submission_state.destroyed_contexts); + INIT_WORK(&guc->submission_state.destroyed_worker, + destroyed_worker_func); return 0; } @@ -1160,6 +1169,7 @@ void intel_guc_submission_fini(struct intel_guc *guc) if (!guc->lrc_desc_pool) return; + guc_flush_destroyed_contexts(guc); guc_lrc_desc_pool_destroy(guc); i915_sched_engine_put(guc->sched_engine); } @@ -1859,11 +1869,30 @@ static void guc_context_sched_disable(struct intel_context *ce) static inline void guc_lrc_desc_unpin(struct intel_context *ce) { struct intel_guc *guc = ce_to_guc(ce); + struct intel_gt *gt = guc_to_gt(guc); + unsigned long flags; + bool disabled; + GEM_BUG_ON(!intel_gt_pm_is_awake(gt)); GEM_BUG_ON(!lrc_desc_registered(guc, ce->guc_id.id)); GEM_BUG_ON(ce != __get_context(guc, ce->guc_id.id)); GEM_BUG_ON(context_enabled(ce)); + /* Seal race with Reset */ + spin_lock_irqsave(&ce->guc_state.lock, flags); + disabled = submission_disabled(guc); + if (likely(!disabled)) { + __intel_gt_pm_get(gt); + set_context_destroyed(ce); + clr_context_registered(ce); + } + spin_unlock_irqrestore(&ce->guc_state.lock, flags); + if (unlikely(disabled)) { + release_guc_id(guc, ce); + __guc_context_destroy(ce); + return; + } + deregister_context(ce, ce->guc_id.id); } @@ -1891,78 +1920,86 @@ static void __guc_context_destroy(struct intel_context *ce) } } +static void guc_flush_destroyed_contexts(struct intel_guc *guc) +{ + struct intel_context *ce, *cn; + unsigned long flags; + + GEM_BUG_ON(!submission_disabled(guc) && + guc_submission_initialized(guc)); + + spin_lock_irqsave(&guc->submission_state.lock, flags); + list_for_each_entry_safe(ce, cn, + &guc->submission_state.destroyed_contexts, + destroyed_link) { + list_del_init(&ce->destroyed_link); + __release_guc_id(guc, ce); + __guc_context_destroy(ce); + } + spin_unlock_irqrestore(&guc->submission_state.lock, flags); +} + +static void deregister_destroyed_contexts(struct intel_guc *guc) +{ + struct intel_context *ce, *cn; + unsigned long flags; + + spin_lock_irqsave(&guc->submission_state.lock, flags); + list_for_each_entry_safe(ce, cn, + &guc->submission_state.destroyed_contexts, + destroyed_link) { + list_del_init(&ce->destroyed_link); + guc_lrc_desc_unpin(ce); + } + spin_unlock_irqrestore(&guc->submission_state.lock, flags); +} + +static void destroyed_worker_func(struct work_struct *w) +{ + struct intel_guc *guc = container_of(w, struct intel_guc, + submission_state.destroyed_worker); + struct intel_gt *gt = guc_to_gt(guc); + int tmp; + + with_intel_gt_pm(gt, tmp) + deregister_destroyed_contexts(guc); +} + static void guc_context_destroy(struct kref *kref) { struct intel_context *ce = container_of(kref, typeof(*ce), ref); - struct intel_runtime_pm *runtime_pm = ce->engine->uncore->rpm; struct intel_guc *guc = ce_to_guc(ce); - intel_wakeref_t wakeref; unsigned long flags; - bool disabled; + bool destroy; /* * 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 or the GuC is in the middle of a reset. */ - if (context_guc_id_invalid(ce)) { - __guc_context_destroy(ce); - return; - } else if (submission_disabled(guc) || - !lrc_desc_registered(guc, ce->guc_id.id)) { - release_guc_id(guc, ce); - __guc_context_destroy(ce); - return; - } - - /* - * We have to acquire the context spinlock and check guc_id again, if it - * is valid it hasn't been stolen and needs to be deregistered. We - * delete this context from the list of unpinned guc_id available to - * steal to seal a race with guc_lrc_desc_pin(). When the G2H CTB - * returns indicating this context has been deregistered the guc_id is - * returned to the pool of available guc_id. - */ spin_lock_irqsave(&guc->submission_state.lock, flags); - if (context_guc_id_invalid(ce)) { - spin_unlock_irqrestore(&guc->submission_state.lock, flags); - __guc_context_destroy(ce); - return; + destroy = submission_disabled(guc) || context_guc_id_invalid(ce) || + !lrc_desc_registered(guc, ce->guc_id.id); + if (likely(!destroy)) { + if (!list_empty(&ce->guc_id.link)) + list_del_init(&ce->guc_id.link); + list_add_tail(&ce->destroyed_link, + &guc->submission_state.destroyed_contexts); + } else { + __release_guc_id(guc, ce); } - - if (!list_empty(&ce->guc_id.link)) - list_del_init(&ce->guc_id.link); spin_unlock_irqrestore(&guc->submission_state.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); - clr_context_registered(ce); - } - spin_unlock_irqrestore(&ce->guc_state.lock, flags); - if (unlikely(disabled)) { - release_guc_id(guc, ce); + if (unlikely(destroy)) { __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 - * 1 CTB to register the context during the first pin and 1 CTB to - * deregister the context when the context is destroyed. Without this - * optimization, a CTB would be needed every pin & unpin. - * - * XXX: Need to acqiure the runtime wakeref as this can be triggered - * from context_free_worker when runtime wakeref is not held. - * guc_lrc_desc_unpin requires the runtime as a GuC register is written - * in H2G CTB to deregister the context. A future patch may defer this - * H2G CTB if the runtime wakeref is zero. + * We use a worker to issue the H2G to deregister the context as we can + * take the GT PM for the first time which isn't allowed from an atomic + * context. */ - with_intel_runtime_pm(runtime_pm, wakeref) - guc_lrc_desc_unpin(ce); + queue_work(system_unbound_wq, &guc->submission_state.destroyed_worker); } static int guc_context_alloc(struct intel_context *ce) @@ -2798,6 +2835,7 @@ int intel_guc_deregister_done_process_msg(struct intel_guc *guc, intel_context_put(ce); } else if (context_destroyed(ce)) { /* Context has been destroyed */ + intel_gt_pm_put_async(guc_to_gt(guc)); release_guc_id(guc, ce); __guc_context_destroy(ce); }
Taking a PM reference to prevent intel_gt_wait_for_idle from short circuiting while a deregister context H2G is in flight. To do this must issue the deregister H2G from a worker as context can be destroyed from an atomic context and taking GT PM ref blows up. Previously we took a runtime PM from this atomic context which worked but will stop working once runtime pm autosuspend in enabled. So this patch is two fold, stop intel_gt_wait_for_idle from short circuting and fix runtime pm autosuspend. v2: (John Harrison) - Split structure changes out in different patch (Tvrtko) - Don't drop lock in deregister_destroyed_contexts v3: (John Harrison) - Flush destroyed contexts before destroying context reg pool Signed-off-by: Matthew Brost <matthew.brost@intel.com> --- drivers/gpu/drm/i915/gt/intel_context.c | 2 + drivers/gpu/drm/i915/gt/intel_context_types.h | 7 + drivers/gpu/drm/i915/gt/intel_engine_pm.h | 5 + drivers/gpu/drm/i915/gt/intel_gt_pm.h | 4 + drivers/gpu/drm/i915/gt/uc/intel_guc.h | 11 ++ .../gpu/drm/i915/gt/uc/intel_guc_submission.c | 146 +++++++++++------- 6 files changed, 121 insertions(+), 54 deletions(-)