From 3a4cdf1982f05d1da434eb3d777554ea6de6769a Mon Sep 17 00:00:00 2001 From: Matthew Brost Date: Wed, 21 Jul 2021 14:50:49 -0700 Subject: [PATCH] drm/i915/guc: Implement GuC context operations for new inteface Implement GuC context operations which includes GuC specific operations alloc, pin, unpin, and destroy. v2: (Daniel Vetter) - Use msleep_interruptible rather than cond_resched in busy loop (Michal) - Remove C++ style comment v3: (Matthew Brost) - Drop GUC_ID_START (John Harrison) - Fix a bunch of typos - Use drm_err rather than drm_dbg for G2H errors (Daniele) - Fix ;; typo - Clean up sched state functions - Add lockdep for guc_id functions - Don't call __release_guc_id when guc_id is invalid - Use MISSING_CASE - Add comment in guc_context_pin - Use shorter path to rpm (Daniele / CI) - Don't call release_guc_id on an invalid guc_id in destroy v4: (Daniel Vetter) - Add FIXME comment Signed-off-by: John Harrison Signed-off-by: Matthew Brost Reviewed-by: John Harrison Signed-off-by: John Harrison Link: https://patchwork.freedesktop.org/patch/msgid/20210721215101.139794-7-matthew.brost@intel.com --- drivers/gpu/drm/i915/gt/intel_context.c | 5 + drivers/gpu/drm/i915/gt/intel_context_types.h | 22 +- drivers/gpu/drm/i915/gt/intel_lrc_reg.h | 1 - drivers/gpu/drm/i915/gt/uc/intel_guc.h | 47 ++ drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c | 4 + drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 670 ++++++++++++++++++++-- drivers/gpu/drm/i915/i915_reg.h | 1 + drivers/gpu/drm/i915/i915_request.c | 1 + 8 files changed, 696 insertions(+), 55 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c index c133844..090c132 100644 --- a/drivers/gpu/drm/i915/gt/intel_context.c +++ b/drivers/gpu/drm/i915/gt/intel_context.c @@ -384,6 +384,11 @@ intel_context_init(struct intel_context *ce, struct intel_engine_cs *engine) mutex_init(&ce->pin_mutex); + spin_lock_init(&ce->guc_state.lock); + + ce->guc_id = GUC_INVALID_LRC_ID; + INIT_LIST_HEAD(&ce->guc_id_link); + i915_active_init(&ce->active, __intel_context_active, __intel_context_retire, 0); } diff --git a/drivers/gpu/drm/i915/gt/intel_context_types.h b/drivers/gpu/drm/i915/gt/intel_context_types.h index 6d99631..606c480 100644 --- a/drivers/gpu/drm/i915/gt/intel_context_types.h +++ b/drivers/gpu/drm/i915/gt/intel_context_types.h @@ -96,6 +96,7 @@ struct intel_context { #define CONTEXT_BANNED 6 #define CONTEXT_FORCE_SINGLE_SUBMISSION 7 #define CONTEXT_NOPREEMPT 8 +#define CONTEXT_LRCA_DIRTY 9 struct { u64 timeout_us; @@ -138,14 +139,29 @@ struct intel_context { u8 wa_bb_page; /* if set, page num reserved for context workarounds */ + struct { + /** lock: protects everything in guc_state */ + spinlock_t lock; + /** + * sched_state: scheduling state of this context using GuC + * submission + */ + u8 sched_state; + } guc_state; + /* GuC scheduling state flags that do not require a lock. */ atomic_t guc_sched_state_no_lock; + /* GuC LRC descriptor ID */ + u16 guc_id; + + /* GuC LRC descriptor reference count */ + atomic_t guc_id_ref; + /* - * GuC LRC descriptor ID - Not assigned in this patch but future patches - * in the series will. + * GuC ID link - in list when unpinned but guc_id still valid in GuC */ - u16 guc_id; + struct list_head guc_id_link; }; #endif /* __INTEL_CONTEXT_TYPES__ */ diff --git a/drivers/gpu/drm/i915/gt/intel_lrc_reg.h b/drivers/gpu/drm/i915/gt/intel_lrc_reg.h index 9548f4a..f785d0e 100644 --- a/drivers/gpu/drm/i915/gt/intel_lrc_reg.h +++ b/drivers/gpu/drm/i915/gt/intel_lrc_reg.h @@ -87,7 +87,6 @@ #define GEN11_CSB_WRITE_PTR_MASK (GEN11_CSB_PTR_MASK << 0) #define MAX_CONTEXT_HW_ID (1 << 21) /* exclusive */ -#define MAX_GUC_CONTEXT_HW_ID (1 << 20) /* exclusive */ #define GEN11_MAX_CONTEXT_HW_ID (1 << 11) /* exclusive */ /* in Gen12 ID 0x7FF is reserved to indicate idle */ #define GEN12_MAX_CONTEXT_HW_ID (GEN11_MAX_CONTEXT_HW_ID - 1) diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc.h b/drivers/gpu/drm/i915/gt/uc/intel_guc.h index 8c7b92f69..7fd6c3e 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc.h +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.h @@ -7,6 +7,7 @@ #define _INTEL_GUC_H_ #include +#include #include "intel_uncore.h" #include "intel_guc_fw.h" @@ -44,6 +45,14 @@ struct intel_guc { void (*disable)(struct intel_guc *guc); } interrupts; + /* + * contexts_lock protects the pool of free guc ids and a linked list of + * guc ids available to be stolen + */ + spinlock_t contexts_lock; + struct ida guc_ids; + struct list_head guc_id_list; + bool submission_selected; struct i915_vma *ads_vma; @@ -101,6 +110,41 @@ intel_guc_send_and_receive(struct intel_guc *guc, const u32 *action, u32 len, response_buf, response_buf_size, 0); } +static inline int intel_guc_send_busy_loop(struct intel_guc *guc, + const u32 *action, + u32 len, + bool loop) +{ + int err; + unsigned int sleep_period_ms = 1; + bool not_atomic = !in_atomic() && !irqs_disabled(); + + /* + * FIXME: Have caller pass in if we are in an atomic context to avoid + * using in_atomic(). It is likely safe here as we check for irqs + * disabled which basically all the spin locks in the i915 do but + * regardless this should be cleaned up. + */ + + /* No sleeping with spin locks, just busy loop */ + might_sleep_if(loop && not_atomic); + +retry: + err = intel_guc_send_nb(guc, action, len); + if (unlikely(err == -EBUSY && loop)) { + if (likely(not_atomic)) { + if (msleep_interruptible(sleep_period_ms)) + return -EINTR; + sleep_period_ms = sleep_period_ms << 1; + } else { + cpu_relax(); + } + goto retry; + } + + return err; +} + static inline void intel_guc_to_host_event_handler(struct intel_guc *guc) { intel_guc_ct_event_handler(&guc->ct); @@ -202,6 +246,9 @@ static inline void intel_guc_disable_msg(struct intel_guc *guc, u32 mask) 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); + 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_ct.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c index 83ec60e..28ff82c 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c @@ -928,6 +928,10 @@ static int ct_process_request(struct intel_guc_ct *ct, struct ct_incoming_msg *r case INTEL_GUC_ACTION_DEFAULT: ret = intel_guc_to_host_process_recv_msg(guc, payload, len); break; + case INTEL_GUC_ACTION_DEREGISTER_CONTEXT_DONE: + ret = intel_guc_deregister_done_process_msg(guc, payload, + len); + break; default: ret = -EOPNOTSUPP; break; 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 53b4a5e..463613a 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c @@ -13,7 +13,9 @@ #include "gt/intel_gt.h" #include "gt/intel_gt_irq.h" #include "gt/intel_gt_pm.h" +#include "gt/intel_gt_requests.h" #include "gt/intel_lrc.h" +#include "gt/intel_lrc_reg.h" #include "gt/intel_mocs.h" #include "gt/intel_ring.h" @@ -85,6 +87,72 @@ static inline void clr_context_enabled(struct intel_context *ce) &ce->guc_sched_state_no_lock); } +/* + * Below is a set of functions which control the GuC scheduling state which + * require a lock, aside from the special case where the functions are called + * from guc_lrc_desc_pin(). In that case it isn't possible for any other code + * path to be executing on the context. + */ +#define SCHED_STATE_WAIT_FOR_DEREGISTER_TO_REGISTER BIT(0) +#define SCHED_STATE_DESTROYED BIT(1) +static inline void init_sched_state(struct intel_context *ce) +{ + /* Only should be called from guc_lrc_desc_pin() */ + atomic_set(&ce->guc_sched_state_no_lock, 0); + ce->guc_state.sched_state = 0; +} + +static inline bool +context_wait_for_deregister_to_register(struct intel_context *ce) +{ + return ce->guc_state.sched_state & + SCHED_STATE_WAIT_FOR_DEREGISTER_TO_REGISTER; +} + +static inline void +set_context_wait_for_deregister_to_register(struct intel_context *ce) +{ + /* Only should be called from guc_lrc_desc_pin() */ + ce->guc_state.sched_state |= + SCHED_STATE_WAIT_FOR_DEREGISTER_TO_REGISTER; +} + +static inline void +clr_context_wait_for_deregister_to_register(struct intel_context *ce) +{ + lockdep_assert_held(&ce->guc_state.lock); + ce->guc_state.sched_state &= + ~SCHED_STATE_WAIT_FOR_DEREGISTER_TO_REGISTER; +} + +static inline bool +context_destroyed(struct intel_context *ce) +{ + return ce->guc_state.sched_state & SCHED_STATE_DESTROYED; +} + +static inline void +set_context_destroyed(struct intel_context *ce) +{ + lockdep_assert_held(&ce->guc_state.lock); + ce->guc_state.sched_state |= SCHED_STATE_DESTROYED; +} + +static inline bool context_guc_id_invalid(struct intel_context *ce) +{ + return ce->guc_id == GUC_INVALID_LRC_ID; +} + +static inline void set_context_guc_id_invalid(struct intel_context *ce) +{ + ce->guc_id = GUC_INVALID_LRC_ID; +} + +static inline struct intel_guc *ce_to_guc(struct intel_context *ce) +{ + return &ce->engine->gt->uc.guc; +} + static inline struct i915_priolist *to_priolist(struct rb_node *rb) { return rb_entry(rb, struct i915_priolist, node); @@ -155,6 +223,9 @@ static int guc_add_request(struct intel_guc *guc, struct i915_request *rq) int len = 0; bool enabled = context_enabled(ce); + GEM_BUG_ON(!atomic_read(&ce->guc_id_ref)); + GEM_BUG_ON(context_guc_id_invalid(ce)); + if (!enabled) { action[len++] = INTEL_GUC_ACTION_SCHED_CONTEXT_MODE_SET; action[len++] = ce->guc_id; @@ -417,6 +488,10 @@ int intel_guc_submission_init(struct intel_guc *guc) xa_init_flags(&guc->context_lookup, XA_FLAGS_LOCK_IRQ); + spin_lock_init(&guc->contexts_lock); + INIT_LIST_HEAD(&guc->guc_id_list); + ida_init(&guc->guc_ids); + return 0; } @@ -429,9 +504,308 @@ void intel_guc_submission_fini(struct intel_guc *guc) i915_sched_engine_put(guc->sched_engine); } -static int guc_context_alloc(struct intel_context *ce) +static inline void queue_request(struct i915_sched_engine *sched_engine, + struct i915_request *rq, + int prio) { - return lrc_alloc(ce, ce->engine); + GEM_BUG_ON(!list_empty(&rq->sched.link)); + list_add_tail(&rq->sched.link, + i915_sched_lookup_priolist(sched_engine, prio)); + set_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags); +} + +static int guc_bypass_tasklet_submit(struct intel_guc *guc, + struct i915_request *rq) +{ + int ret; + + __i915_request_submit(rq); + + trace_i915_request_in(rq, 0); + + guc_set_lrc_tail(rq); + ret = guc_add_request(guc, rq); + if (ret == -EBUSY) + guc->stalled_request = rq; + + return ret; +} + +static void guc_submit_request(struct i915_request *rq) +{ + struct i915_sched_engine *sched_engine = rq->engine->sched_engine; + struct intel_guc *guc = &rq->engine->gt->uc.guc; + unsigned long flags; + + /* 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)) + queue_request(sched_engine, rq, rq_prio(rq)); + else if (guc_bypass_tasklet_submit(guc, rq) == -EBUSY) + tasklet_hi_schedule(&sched_engine->tasklet); + + spin_unlock_irqrestore(&sched_engine->lock, flags); +} + +static int new_guc_id(struct intel_guc *guc) +{ + return ida_simple_get(&guc->guc_ids, 0, + GUC_MAX_LRC_DESCRIPTORS, GFP_KERNEL | + __GFP_RETRY_MAYFAIL | __GFP_NOWARN); +} + +static void __release_guc_id(struct intel_guc *guc, struct intel_context *ce) +{ + if (!context_guc_id_invalid(ce)) { + ida_simple_remove(&guc->guc_ids, ce->guc_id); + reset_lrc_desc(guc, ce->guc_id); + set_context_guc_id_invalid(ce); + } + if (!list_empty(&ce->guc_id_link)) + list_del_init(&ce->guc_id_link); +} + +static void release_guc_id(struct intel_guc *guc, struct intel_context *ce) +{ + unsigned long flags; + + spin_lock_irqsave(&guc->contexts_lock, flags); + __release_guc_id(guc, ce); + spin_unlock_irqrestore(&guc->contexts_lock, flags); +} + +static int steal_guc_id(struct intel_guc *guc) +{ + struct intel_context *ce; + int guc_id; + + lockdep_assert_held(&guc->contexts_lock); + + if (!list_empty(&guc->guc_id_list)) { + ce = list_first_entry(&guc->guc_id_list, + struct intel_context, + guc_id_link); + + GEM_BUG_ON(atomic_read(&ce->guc_id_ref)); + GEM_BUG_ON(context_guc_id_invalid(ce)); + + list_del_init(&ce->guc_id_link); + guc_id = ce->guc_id; + set_context_guc_id_invalid(ce); + return guc_id; + } else { + return -EAGAIN; + } +} + +static int assign_guc_id(struct intel_guc *guc, u16 *out) +{ + int ret; + + lockdep_assert_held(&guc->contexts_lock); + + ret = new_guc_id(guc); + if (unlikely(ret < 0)) { + ret = steal_guc_id(guc); + if (ret < 0) + return ret; + } + + *out = ret; + return 0; +} + +#define PIN_GUC_ID_TRIES 4 +static int pin_guc_id(struct intel_guc *guc, struct intel_context *ce) +{ + int ret = 0; + unsigned long flags, tries = PIN_GUC_ID_TRIES; + + GEM_BUG_ON(atomic_read(&ce->guc_id_ref)); + +try_again: + spin_lock_irqsave(&guc->contexts_lock, flags); + + if (context_guc_id_invalid(ce)) { + ret = assign_guc_id(guc, &ce->guc_id); + if (ret) + goto out_unlock; + ret = 1; /* Indidcates newly assigned guc_id */ + } + if (!list_empty(&ce->guc_id_link)) + list_del_init(&ce->guc_id_link); + atomic_inc(&ce->guc_id_ref); + +out_unlock: + spin_unlock_irqrestore(&guc->contexts_lock, flags); + + /* + * -EAGAIN indicates no guc_ids are available, let's retire any + * outstanding requests to see if that frees up a guc_id. If the first + * retire didn't help, insert a sleep with the timeslice duration before + * attempting to retire more requests. Double the sleep period each + * subsequent pass before finally giving up. The sleep period has max of + * 100ms and minimum of 1ms. + */ + if (ret == -EAGAIN && --tries) { + if (PIN_GUC_ID_TRIES - tries > 1) { + unsigned int timeslice_shifted = + ce->engine->props.timeslice_duration_ms << + (PIN_GUC_ID_TRIES - tries - 2); + unsigned int max = min_t(unsigned int, 100, + timeslice_shifted); + + msleep(max_t(unsigned int, max, 1)); + } + intel_gt_retire_requests(guc_to_gt(guc)); + goto try_again; + } + + return ret; +} + +static void unpin_guc_id(struct intel_guc *guc, struct intel_context *ce) +{ + unsigned long flags; + + GEM_BUG_ON(atomic_read(&ce->guc_id_ref) < 0); + + if (unlikely(context_guc_id_invalid(ce))) + return; + + spin_lock_irqsave(&guc->contexts_lock, flags); + if (!context_guc_id_invalid(ce) && list_empty(&ce->guc_id_link) && + !atomic_read(&ce->guc_id_ref)) + list_add_tail(&ce->guc_id_link, &guc->guc_id_list); + spin_unlock_irqrestore(&guc->contexts_lock, flags); +} + +static int __guc_action_register_context(struct intel_guc *guc, + u32 guc_id, + u32 offset) +{ + u32 action[] = { + INTEL_GUC_ACTION_REGISTER_CONTEXT, + guc_id, + offset, + }; + + return intel_guc_send_busy_loop(guc, action, ARRAY_SIZE(action), true); +} + +static int register_context(struct intel_context *ce) +{ + struct intel_guc *guc = ce_to_guc(ce); + u32 offset = intel_guc_ggtt_offset(guc, guc->lrc_desc_pool) + + ce->guc_id * sizeof(struct guc_lrc_desc); + + return __guc_action_register_context(guc, ce->guc_id, offset); +} + +static int __guc_action_deregister_context(struct intel_guc *guc, + u32 guc_id) +{ + u32 action[] = { + INTEL_GUC_ACTION_DEREGISTER_CONTEXT, + guc_id, + }; + + return intel_guc_send_busy_loop(guc, action, ARRAY_SIZE(action), true); +} + +static int deregister_context(struct intel_context *ce, u32 guc_id) +{ + struct intel_guc *guc = ce_to_guc(ce); + + return __guc_action_deregister_context(guc, guc_id); +} + +static intel_engine_mask_t adjust_engine_mask(u8 class, intel_engine_mask_t mask) +{ + switch (class) { + case RENDER_CLASS: + return mask >> RCS0; + case VIDEO_ENHANCEMENT_CLASS: + return mask >> VECS0; + case VIDEO_DECODE_CLASS: + return mask >> VCS0; + case COPY_ENGINE_CLASS: + return mask >> BCS0; + default: + MISSING_CASE(class); + return 0; + } +} + +static void guc_context_policy_init(struct intel_engine_cs *engine, + struct guc_lrc_desc *desc) +{ + desc->policy_flags = 0; + + desc->execution_quantum = CONTEXT_POLICY_DEFAULT_EXECUTION_QUANTUM_US; + desc->preemption_timeout = CONTEXT_POLICY_DEFAULT_PREEMPTION_TIME_US; +} + +static int guc_lrc_desc_pin(struct intel_context *ce) +{ + struct intel_engine_cs *engine = ce->engine; + struct intel_runtime_pm *runtime_pm = engine->uncore->rpm; + struct intel_guc *guc = &engine->gt->uc.guc; + u32 desc_idx = ce->guc_id; + struct guc_lrc_desc *desc; + bool context_registered; + intel_wakeref_t wakeref; + int ret = 0; + + GEM_BUG_ON(!engine->mask); + + /* + * Ensure LRC + CT vmas are is same region as write barrier is done + * based on CT vma region. + */ + GEM_BUG_ON(i915_gem_object_is_lmem(guc->ct.vma->obj) != + i915_gem_object_is_lmem(ce->ring->vma->obj)); + + context_registered = lrc_desc_registered(guc, desc_idx); + + reset_lrc_desc(guc, desc_idx); + set_lrc_desc_registered(guc, desc_idx, ce); + + desc = __get_lrc_desc(guc, desc_idx); + desc->engine_class = engine_class_to_guc_class(engine->class); + desc->engine_submit_mask = adjust_engine_mask(engine->class, + engine->mask); + desc->hw_context_desc = ce->lrc.lrca; + desc->priority = GUC_CLIENT_PRIORITY_KMD_NORMAL; + desc->context_flags = CONTEXT_REGISTRATION_FLAG_KMD; + guc_context_policy_init(engine, desc); + init_sched_state(ce); + + /* + * The context_lookup xarray is used to determine if the hardware + * context is currently registered. There are two cases in which it + * could be registered either the guc_id has been stolen from another + * context or the lrc descriptor address of this context has changed. In + * either case the context needs to be deregistered with the GuC before + * registering this context. + */ + if (context_registered) { + set_context_wait_for_deregister_to_register(ce); + intel_context_get(ce); + + /* + * If stealing the guc_id, this ce has the same guc_id as the + * context whose guc_id was stolen. + */ + with_intel_runtime_pm(runtime_pm, wakeref) + ret = deregister_context(ce, ce->guc_id); + } else { + with_intel_runtime_pm(runtime_pm, wakeref) + ret = register_context(ce); + } + + return ret; } static int guc_context_pre_pin(struct intel_context *ce, @@ -443,36 +817,144 @@ static int guc_context_pre_pin(struct intel_context *ce, static int guc_context_pin(struct intel_context *ce, void *vaddr) { + if (i915_ggtt_offset(ce->state) != + (ce->lrc.lrca & CTX_GTT_ADDRESS_MASK)) + set_bit(CONTEXT_LRCA_DIRTY, &ce->flags); + + /* + * GuC context gets pinned in guc_request_alloc. See that function for + * explaination of why. + */ + return lrc_pin(ce, ce->engine, vaddr); } +static void guc_context_unpin(struct intel_context *ce) +{ + struct intel_guc *guc = ce_to_guc(ce); + + unpin_guc_id(guc, ce); + lrc_unpin(ce); +} + +static void guc_context_post_unpin(struct intel_context *ce) +{ + lrc_post_unpin(ce); +} + +static inline void guc_lrc_desc_unpin(struct intel_context *ce) +{ + struct intel_guc *guc = ce_to_guc(ce); + unsigned long flags; + + GEM_BUG_ON(!lrc_desc_registered(guc, ce->guc_id)); + GEM_BUG_ON(ce != __get_context(guc, ce->guc_id)); + + 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); +} + +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; + + /* + * 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)) { + lrc_destroy(kref); + return; + } else if (!lrc_desc_registered(guc, ce->guc_id)) { + release_guc_id(guc, ce); + lrc_destroy(kref); + 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_ids 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_ids. + */ + spin_lock_irqsave(&guc->contexts_lock, flags); + if (context_guc_id_invalid(ce)) { + spin_unlock_irqrestore(&guc->contexts_lock, flags); + lrc_destroy(kref); + return; + } + + if (!list_empty(&ce->guc_id_link)) + list_del_init(&ce->guc_id_link); + spin_unlock_irqrestore(&guc->contexts_lock, flags); + + /* + * 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. + */ + with_intel_runtime_pm(runtime_pm, wakeref) + guc_lrc_desc_unpin(ce); +} + +static int guc_context_alloc(struct intel_context *ce) +{ + return lrc_alloc(ce, ce->engine); +} + static const struct intel_context_ops guc_context_ops = { .alloc = guc_context_alloc, .pre_pin = guc_context_pre_pin, .pin = guc_context_pin, - .unpin = lrc_unpin, - .post_unpin = lrc_post_unpin, + .unpin = guc_context_unpin, + .post_unpin = guc_context_post_unpin, .enter = intel_context_enter_engine, .exit = intel_context_exit_engine, .reset = lrc_reset, - .destroy = lrc_destroy, + .destroy = guc_context_destroy, }; -static int guc_request_alloc(struct i915_request *request) +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); +} + +static int guc_request_alloc(struct i915_request *rq) { + struct intel_context *ce = rq->context; + struct intel_guc *guc = ce_to_guc(ce); int ret; - GEM_BUG_ON(!intel_context_is_pinned(request->context)); + GEM_BUG_ON(!intel_context_is_pinned(rq->context)); /* * Flush enough space to reduce the likelihood of waiting after * we start building the request - in which case we will just * have to repeat work. */ - request->reserved_space += GUC_REQUEST_SIZE; + rq->reserved_space += GUC_REQUEST_SIZE; /* * Note that after this point, we have committed to using @@ -483,56 +965,47 @@ static int guc_request_alloc(struct i915_request *request) */ /* Unconditionally invalidate GPU caches and TLBs. */ - ret = request->engine->emit_flush(request, EMIT_INVALIDATE); + ret = rq->engine->emit_flush(rq, EMIT_INVALIDATE); if (ret) return ret; - request->reserved_space -= GUC_REQUEST_SIZE; - return 0; -} + rq->reserved_space -= GUC_REQUEST_SIZE; -static inline void queue_request(struct i915_sched_engine *sched_engine, - struct i915_request *rq, - int prio) -{ - GEM_BUG_ON(!list_empty(&rq->sched.link)); - list_add_tail(&rq->sched.link, - i915_sched_lookup_priolist(sched_engine, prio)); - set_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags); -} - -static int guc_bypass_tasklet_submit(struct intel_guc *guc, - struct i915_request *rq) -{ - int ret; - - __i915_request_submit(rq); - - trace_i915_request_in(rq, 0); - - guc_set_lrc_tail(rq); - ret = guc_add_request(guc, rq); - if (ret == -EBUSY) - guc->stalled_request = rq; - - return ret; -} - -static void guc_submit_request(struct i915_request *rq) -{ - struct i915_sched_engine *sched_engine = rq->engine->sched_engine; - struct intel_guc *guc = &rq->engine->gt->uc.guc; - unsigned long flags; + /* + * Call pin_guc_id here rather than in the pinning step as with + * dma_resv, contexts can be repeatedly pinned / unpinned trashing the + * guc_ids and creating horrible race conditions. This is especially bad + * when guc_ids are being stolen due to over subscription. By the time + * this function is reached, it is guaranteed that the guc_id will be + * persistent until the generated request is retired. Thus, sealing these + * race conditions. It is still safe to fail here if guc_ids are + * exhausted and return -EAGAIN to the user indicating that they can try + * again in the future. + * + * There is no need for a lock here as the timeline mutex ensures at + * most one context can be executing this code path at once. The + * guc_id_ref is incremented once for every request in flight and + * decremented on each retire. When it is zero, a lock around the + * increment (in pin_guc_id) is needed to seal a race with unpin_guc_id. + */ + if (atomic_add_unless(&ce->guc_id_ref, 1, 0)) + return 0; - /* Will be called from irq-context when using foreign fences. */ - spin_lock_irqsave(&sched_engine->lock, flags); + ret = pin_guc_id(guc, ce); /* returns 1 if new guc_id assigned */ + if (unlikely(ret < 0)) + return ret; + if (context_needs_register(ce, !!ret)) { + ret = guc_lrc_desc_pin(ce); + if (unlikely(ret)) { /* unwind */ + atomic_dec(&ce->guc_id_ref); + unpin_guc_id(guc, ce); + return ret; + } + } - if (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); + clear_bit(CONTEXT_LRCA_DIRTY, &ce->flags); - spin_unlock_irqrestore(&sched_engine->lock, flags); + return 0; } static void sanitize_hwsp(struct intel_engine_cs *engine) @@ -606,6 +1079,41 @@ static void guc_set_default_submission(struct intel_engine_cs *engine) engine->submit_request = guc_submit_request; } +static inline void guc_kernel_context_pin(struct intel_guc *guc, + struct intel_context *ce) +{ + if (context_guc_id_invalid(ce)) + pin_guc_id(guc, ce); + guc_lrc_desc_pin(ce); +} + +static inline void guc_init_lrc_mapping(struct intel_guc *guc) +{ + struct intel_gt *gt = guc_to_gt(guc); + struct intel_engine_cs *engine; + enum intel_engine_id id; + + /* make sure all descriptors are clean... */ + xa_destroy(&guc->context_lookup); + + /* + * Some contexts might have been pinned before we enabled GuC + * submission, so we need to add them to the GuC bookeeping. + * Also, after a reset the of the GuC we want to make sure that the + * information shared with GuC is properly reset. The kernel LRCs are + * not attached to the gem_context, so they need to be added separately. + * + * Note: we purposefully do not check the return of guc_lrc_desc_pin, + * because that function can only fail if a reset is just starting. This + * is at the end of reset so presumably another reset isn't happening + * and even it did this code would be run again. + */ + + for_each_engine(engine, gt, id) + if (engine->kernel_context) + guc_kernel_context_pin(guc, engine->kernel_context); +} + static void guc_release(struct intel_engine_cs *engine) { engine->sanitize = NULL; /* no longer in control, nothing to sanitize */ @@ -718,6 +1226,7 @@ int intel_guc_submission_setup(struct intel_engine_cs *engine) void intel_guc_submission_enable(struct intel_guc *guc) { + guc_init_lrc_mapping(guc); } void intel_guc_submission_disable(struct intel_guc *guc) @@ -743,3 +1252,62 @@ void intel_guc_submission_init_early(struct intel_guc *guc) { guc->submission_selected = __guc_submission_selected(guc); } + +static inline struct intel_context * +g2h_context_lookup(struct intel_guc *guc, u32 desc_idx) +{ + struct intel_context *ce; + + if (unlikely(desc_idx >= GUC_MAX_LRC_DESCRIPTORS)) { + drm_err(&guc_to_gt(guc)->i915->drm, + "Invalid desc_idx %u", desc_idx); + return NULL; + } + + ce = __get_context(guc, desc_idx); + if (unlikely(!ce)) { + drm_err(&guc_to_gt(guc)->i915->drm, + "Context is NULL, desc_idx %u", desc_idx); + return NULL; + } + + return ce; +} + +int intel_guc_deregister_done_process_msg(struct intel_guc *guc, + const u32 *msg, + u32 len) +{ + struct intel_context *ce; + u32 desc_idx = msg[0]; + + if (unlikely(len < 1)) { + drm_err(&guc_to_gt(guc)->i915->drm, "Invalid length %u", len); + return -EPROTO; + } + + ce = g2h_context_lookup(guc, desc_idx); + if (unlikely(!ce)) + return -EPROTO; + + if (context_wait_for_deregister_to_register(ce)) { + struct intel_runtime_pm *runtime_pm = + &ce->engine->gt->i915->runtime_pm; + intel_wakeref_t wakeref; + + /* + * Previous owner of this guc_id has been deregistered, now safe + * register this context. + */ + with_intel_runtime_pm(runtime_pm, wakeref) + register_context(ce); + clr_context_wait_for_deregister_to_register(ce); + intel_context_put(ce); + } else if (context_destroyed(ce)) { + /* Context has been destroyed */ + release_guc_id(guc, ce); + lrc_destroy(&ce->ref); + } + + return 0; +} diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index b956e3a..1022400 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -4142,6 +4142,7 @@ enum { FAULT_AND_CONTINUE /* Unsupported */ }; +#define CTX_GTT_ADDRESS_MASK GENMASK(31, 12) #define GEN8_CTX_VALID (1 << 0) #define GEN8_CTX_FORCE_PD_RESTORE (1 << 1) #define GEN8_CTX_FORCE_RESTORE (1 << 2) diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c index d3de9f6..d35d7c9 100644 --- a/drivers/gpu/drm/i915/i915_request.c +++ b/drivers/gpu/drm/i915/i915_request.c @@ -407,6 +407,7 @@ bool i915_request_retire(struct i915_request *rq) */ if (!list_empty(&rq->sched.link)) remove_from_engine(rq); + atomic_dec(&rq->context->guc_id_ref); GEM_BUG_ON(!llist_empty(&rq->execute_cb)); __list_del_entry(&rq->link); /* poison neither prev/next (RCU walks) */ -- 2.7.4