diff options
Diffstat (limited to 'drivers/gpu/drm/i915/i915_request.c')
| -rw-r--r-- | drivers/gpu/drm/i915/i915_request.c | 548 |
1 files changed, 291 insertions, 257 deletions
diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c index c88e538b2ef4..a195a92d0105 100644 --- a/drivers/gpu/drm/i915/i915_request.c +++ b/drivers/gpu/drm/i915/i915_request.c @@ -29,16 +29,20 @@ #include <linux/sched/clock.h> #include <linux/sched/signal.h> +#include "gem/i915_gem_context.h" +#include "gt/intel_context.h" + #include "i915_active.h" #include "i915_drv.h" #include "i915_globals.h" -#include "i915_reset.h" #include "intel_pm.h" struct execute_cb { struct list_head link; struct irq_work work; struct i915_sw_fence *fence; + void (*hook)(struct i915_request *rq, struct dma_fence *signal); + struct i915_request *signal; }; static struct i915_global_request { @@ -132,19 +136,6 @@ i915_request_remove_from_client(struct i915_request *request) spin_unlock(&file_priv->mm.lock); } -static void reserve_gt(struct drm_i915_private *i915) -{ - if (!i915->gt.active_requests++) - i915_gem_unpark(i915); -} - -static void unreserve_gt(struct drm_i915_private *i915) -{ - GEM_BUG_ON(!i915->gt.active_requests); - if (!--i915->gt.active_requests) - i915_gem_park(i915); -} - static void advance_ring(struct i915_request *request) { struct intel_ring *ring = request->ring; @@ -192,84 +183,23 @@ static void free_capture_list(struct i915_request *request) } } -static void __retire_engine_request(struct intel_engine_cs *engine, - struct i915_request *rq) -{ - GEM_TRACE("%s(%s) fence %llx:%lld, current %d\n", - __func__, engine->name, - rq->fence.context, rq->fence.seqno, - hwsp_seqno(rq)); - - GEM_BUG_ON(!i915_request_completed(rq)); - - local_irq_disable(); - - spin_lock(&engine->timeline.lock); - GEM_BUG_ON(!list_is_first(&rq->link, &engine->timeline.requests)); - list_del_init(&rq->link); - spin_unlock(&engine->timeline.lock); - - spin_lock(&rq->lock); - i915_request_mark_complete(rq); - if (!i915_request_signaled(rq)) - dma_fence_signal_locked(&rq->fence); - if (test_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT, &rq->fence.flags)) - i915_request_cancel_breadcrumb(rq); - if (rq->waitboost) { - GEM_BUG_ON(!atomic_read(&rq->i915->gt_pm.rps.num_waiters)); - atomic_dec(&rq->i915->gt_pm.rps.num_waiters); - } - spin_unlock(&rq->lock); - - local_irq_enable(); - - /* - * The backing object for the context is done after switching to the - * *next* context. Therefore we cannot retire the previous context until - * the next context has already started running. However, since we - * cannot take the required locks at i915_request_submit() we - * defer the unpinning of the active context to now, retirement of - * the subsequent request. - */ - if (engine->last_retired_context) - intel_context_unpin(engine->last_retired_context); - engine->last_retired_context = rq->hw_context; -} - -static void __retire_engine_upto(struct intel_engine_cs *engine, - struct i915_request *rq) -{ - struct i915_request *tmp; - - if (list_empty(&rq->link)) - return; - - do { - tmp = list_first_entry(&engine->timeline.requests, - typeof(*tmp), link); - - GEM_BUG_ON(tmp->engine != engine); - __retire_engine_request(engine, tmp); - } while (tmp != rq); -} - -static void i915_request_retire(struct i915_request *request) +static bool i915_request_retire(struct i915_request *rq) { struct i915_active_request *active, *next; - GEM_TRACE("%s fence %llx:%lld, current %d\n", - request->engine->name, - request->fence.context, request->fence.seqno, - hwsp_seqno(request)); + lockdep_assert_held(&rq->i915->drm.struct_mutex); + if (!i915_request_completed(rq)) + return false; - lockdep_assert_held(&request->i915->drm.struct_mutex); - GEM_BUG_ON(!i915_sw_fence_signaled(&request->submit)); - GEM_BUG_ON(!i915_request_completed(request)); + GEM_TRACE("%s fence %llx:%lld, current %d\n", + rq->engine->name, + rq->fence.context, rq->fence.seqno, + hwsp_seqno(rq)); - trace_i915_request_retire(request); + GEM_BUG_ON(!i915_sw_fence_signaled(&rq->submit)); + trace_i915_request_retire(rq); - advance_ring(request); - free_capture_list(request); + advance_ring(rq); /* * Walk through the active list, calling retire on each. This allows @@ -281,7 +211,7 @@ static void i915_request_retire(struct i915_request *request) * pass along the auxiliary information (to avoid dereferencing * the node after the callback). */ - list_for_each_entry_safe(active, next, &request->active_list, link) { + list_for_each_entry_safe(active, next, &rq->active_list, link) { /* * In microbenchmarks or focusing upon time inside the kernel, * we may spend an inordinate amount of time simply handling @@ -297,19 +227,40 @@ static void i915_request_retire(struct i915_request *request) INIT_LIST_HEAD(&active->link); RCU_INIT_POINTER(active->request, NULL); - active->retire(active, request); + active->retire(active, rq); } - i915_request_remove_from_client(request); + local_irq_disable(); - intel_context_unpin(request->hw_context); + spin_lock(&rq->engine->active.lock); + list_del(&rq->sched.link); + spin_unlock(&rq->engine->active.lock); - __retire_engine_upto(request->engine, request); + spin_lock(&rq->lock); + i915_request_mark_complete(rq); + if (!i915_request_signaled(rq)) + dma_fence_signal_locked(&rq->fence); + if (test_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT, &rq->fence.flags)) + i915_request_cancel_breadcrumb(rq); + if (rq->waitboost) { + GEM_BUG_ON(!atomic_read(&rq->i915->gt_pm.rps.num_waiters)); + atomic_dec(&rq->i915->gt_pm.rps.num_waiters); + } + spin_unlock(&rq->lock); - unreserve_gt(request->i915); + local_irq_enable(); + + intel_context_exit(rq->hw_context); + intel_context_unpin(rq->hw_context); + + i915_request_remove_from_client(rq); + list_del(&rq->link); + + free_capture_list(rq); + i915_sched_node_fini(&rq->sched); + i915_request_put(rq); - i915_sched_node_fini(&request->sched); - i915_request_put(request); + return true; } void i915_request_retire_upto(struct i915_request *rq) @@ -331,9 +282,7 @@ void i915_request_retire_upto(struct i915_request *rq) do { tmp = list_first_entry(&ring->request_list, typeof(*tmp), ring_link); - - i915_request_retire(tmp); - } while (tmp != rq); + } while (i915_request_retire(tmp) && tmp != rq); } static void irq_execute_cb(struct irq_work *wrk) @@ -344,6 +293,17 @@ static void irq_execute_cb(struct irq_work *wrk) kmem_cache_free(global.slab_execute_cbs, cb); } +static void irq_execute_cb_hook(struct irq_work *wrk) +{ + struct execute_cb *cb = container_of(wrk, typeof(*cb), work); + + cb->hook(container_of(cb->fence, struct i915_request, submit), + &cb->signal->fence); + i915_request_put(cb->signal); + + irq_execute_cb(wrk); +} + static void __notify_execute_cb(struct i915_request *rq) { struct execute_cb *cb; @@ -370,14 +330,19 @@ static void __notify_execute_cb(struct i915_request *rq) } static int -i915_request_await_execution(struct i915_request *rq, - struct i915_request *signal, - gfp_t gfp) +__i915_request_await_execution(struct i915_request *rq, + struct i915_request *signal, + void (*hook)(struct i915_request *rq, + struct dma_fence *signal), + gfp_t gfp) { struct execute_cb *cb; - if (i915_request_is_active(signal)) + if (i915_request_is_active(signal)) { + if (hook) + hook(rq, &signal->fence); return 0; + } cb = kmem_cache_alloc(global.slab_execute_cbs, gfp); if (!cb) @@ -387,8 +352,18 @@ i915_request_await_execution(struct i915_request *rq, i915_sw_fence_await(cb->fence); init_irq_work(&cb->work, irq_execute_cb); + if (hook) { + cb->hook = hook; + cb->signal = i915_request_get(signal); + cb->work.func = irq_execute_cb_hook; + } + spin_lock_irq(&signal->lock); if (i915_request_is_active(signal)) { + if (hook) { + hook(rq, &signal->fence); + i915_request_put(signal); + } i915_sw_fence_complete(cb->fence); kmem_cache_free(global.slab_execute_cbs, cb); } else { @@ -399,28 +374,17 @@ i915_request_await_execution(struct i915_request *rq, return 0; } -static void move_to_timeline(struct i915_request *request, - struct i915_timeline *timeline) -{ - GEM_BUG_ON(request->timeline == &request->engine->timeline); - lockdep_assert_held(&request->engine->timeline.lock); - - spin_lock(&request->timeline->lock); - list_move_tail(&request->link, &timeline->requests); - spin_unlock(&request->timeline->lock); -} - void __i915_request_submit(struct i915_request *request) { struct intel_engine_cs *engine = request->engine; - GEM_TRACE("%s fence %llx:%lld -> current %d\n", + GEM_TRACE("%s fence %llx:%lld, current %d\n", engine->name, request->fence.context, request->fence.seqno, hwsp_seqno(request)); GEM_BUG_ON(!irqs_disabled()); - lockdep_assert_held(&engine->timeline.lock); + lockdep_assert_held(&engine->active.lock); if (i915_gem_context_is_banned(request->gem_context)) i915_request_skip(request, -EIO); @@ -443,11 +407,13 @@ void __i915_request_submit(struct i915_request *request) */ if (request->sched.semaphores && i915_sw_fence_signaled(&request->semaphore)) - request->hw_context->saturated |= request->sched.semaphores; + engine->saturated |= request->sched.semaphores; /* We may be recursing from the signal callback of another i915 fence */ spin_lock_nested(&request->lock, SINGLE_DEPTH_NESTING); + list_move_tail(&request->sched.link, &engine->active.requests); + GEM_BUG_ON(test_bit(I915_FENCE_FLAG_ACTIVE, &request->fence.flags)); set_bit(I915_FENCE_FLAG_ACTIVE, &request->fence.flags); @@ -463,8 +429,7 @@ void __i915_request_submit(struct i915_request *request) engine->emit_fini_breadcrumb(request, request->ring->vaddr + request->postfix); - /* Transfer from per-context onto the global per-engine timeline */ - move_to_timeline(request, &engine->timeline); + engine->serial++; trace_i915_request_execute(request); } @@ -475,11 +440,11 @@ void i915_request_submit(struct i915_request *request) unsigned long flags; /* Will be called from irq-context when using foreign fences. */ - spin_lock_irqsave(&engine->timeline.lock, flags); + spin_lock_irqsave(&engine->active.lock, flags); __i915_request_submit(request); - spin_unlock_irqrestore(&engine->timeline.lock, flags); + spin_unlock_irqrestore(&engine->active.lock, flags); } void __i915_request_unsubmit(struct i915_request *request) @@ -492,7 +457,7 @@ void __i915_request_unsubmit(struct i915_request *request) hwsp_seqno(request)); GEM_BUG_ON(!irqs_disabled()); - lockdep_assert_held(&engine->timeline.lock); + lockdep_assert_held(&engine->active.lock); /* * Only unwind in reverse order, required so that the per-context list @@ -510,8 +475,11 @@ void __i915_request_unsubmit(struct i915_request *request) spin_unlock(&request->lock); - /* Transfer back from the global per-engine timeline to per-context */ - move_to_timeline(request, request->timeline); + /* We've already spun, don't charge on resubmitting. */ + if (request->sched.semaphores && i915_request_started(request)) { + request->sched.attr.priority |= I915_PRIORITY_NOSEMAPHORE; + request->sched.semaphores = 0; + } /* * We don't need to wake_up any waiters on request->execute, they @@ -528,11 +496,11 @@ void i915_request_unsubmit(struct i915_request *request) unsigned long flags; /* Will be called from irq-context when using foreign fences. */ - spin_lock_irqsave(&engine->timeline.lock, flags); + spin_lock_irqsave(&engine->active.lock, flags); __i915_request_unsubmit(request); - spin_unlock_irqrestore(&engine->timeline.lock, flags); + spin_unlock_irqrestore(&engine->active.lock, flags); } static int __i915_sw_fence_call @@ -588,16 +556,13 @@ static void ring_retire_requests(struct intel_ring *ring) { struct i915_request *rq, *rn; - list_for_each_entry_safe(rq, rn, &ring->request_list, ring_link) { - if (!i915_request_completed(rq)) + list_for_each_entry_safe(rq, rn, &ring->request_list, ring_link) + if (!i915_request_retire(rq)) break; - - i915_request_retire(rq); - } } static noinline struct i915_request * -i915_request_alloc_slow(struct intel_context *ce) +request_alloc_slow(struct intel_context *ce, gfp_t gfp) { struct intel_ring *ring = ce->ring; struct i915_request *rq; @@ -605,6 +570,18 @@ i915_request_alloc_slow(struct intel_context *ce) if (list_empty(&ring->request_list)) goto out; + if (!gfpflags_allow_blocking(gfp)) + goto out; + + /* Move our oldest request to the slab-cache (if not in use!) */ + rq = list_first_entry(&ring->request_list, typeof(*rq), ring_link); + i915_request_retire(rq); + + rq = kmem_cache_alloc(global.slab_requests, + gfp | __GFP_RETRY_MAYFAIL | __GFP_NOWARN); + if (rq) + return rq; + /* Ratelimit ourselves to prevent oom from malicious clients */ rq = list_last_entry(&ring->request_list, typeof(*rq), ring_link); cond_synchronize_rcu(rq->rcustate); @@ -613,62 +590,21 @@ i915_request_alloc_slow(struct intel_context *ce) ring_retire_requests(ring); out: - return kmem_cache_alloc(global.slab_requests, GFP_KERNEL); + return kmem_cache_alloc(global.slab_requests, gfp); } -/** - * i915_request_alloc - allocate a request structure - * - * @engine: engine that we wish to issue the request on. - * @ctx: context that the request will be associated with. - * - * Returns a pointer to the allocated request if successful, - * or an error code if not. - */ struct i915_request * -i915_request_alloc(struct intel_engine_cs *engine, struct i915_gem_context *ctx) +__i915_request_create(struct intel_context *ce, gfp_t gfp) { - struct drm_i915_private *i915 = engine->i915; - struct intel_context *ce; - struct i915_timeline *tl; + struct i915_timeline *tl = ce->ring->timeline; struct i915_request *rq; u32 seqno; int ret; - lockdep_assert_held(&i915->drm.struct_mutex); - - /* - * Preempt contexts are reserved for exclusive use to inject a - * preemption context switch. They are never to be used for any trivial - * request! - */ - GEM_BUG_ON(ctx == i915->preempt_context); - - /* - * ABI: Before userspace accesses the GPU (e.g. execbuffer), report - * EIO if the GPU is already wedged. - */ - ret = i915_terminally_wedged(i915); - if (ret) - return ERR_PTR(ret); - - /* - * Pinning the contexts may generate requests in order to acquire - * GGTT space, so do this first before we reserve a seqno for - * ourselves. - */ - ce = intel_context_pin(ctx, engine); - if (IS_ERR(ce)) - return ERR_CAST(ce); - - reserve_gt(i915); - mutex_lock(&ce->ring->timeline->mutex); + might_sleep_if(gfpflags_allow_blocking(gfp)); - /* Move our oldest request to the slab-cache (if not in use!) */ - rq = list_first_entry(&ce->ring->request_list, typeof(*rq), ring_link); - if (!list_is_last(&rq->ring_link, &ce->ring->request_list) && - i915_request_completed(rq)) - i915_request_retire(rq); + /* Check that the caller provided an already pinned context */ + __intel_context_pin(ce); /* * Beware: Dragons be flying overhead. @@ -700,30 +636,25 @@ i915_request_alloc(struct intel_engine_cs *engine, struct i915_gem_context *ctx) * Do not use kmem_cache_zalloc() here! */ rq = kmem_cache_alloc(global.slab_requests, - GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN); + gfp | __GFP_RETRY_MAYFAIL | __GFP_NOWARN); if (unlikely(!rq)) { - rq = i915_request_alloc_slow(ce); + rq = request_alloc_slow(ce, gfp); if (!rq) { ret = -ENOMEM; goto err_unreserve; } } - INIT_LIST_HEAD(&rq->active_list); - INIT_LIST_HEAD(&rq->execute_cb); - - tl = ce->ring->timeline; ret = i915_timeline_get_seqno(tl, rq, &seqno); if (ret) goto err_free; - rq->i915 = i915; - rq->engine = engine; - rq->gem_context = ctx; + rq->i915 = ce->engine->i915; rq->hw_context = ce; + rq->gem_context = ce->gem_context; + rq->engine = ce->engine; rq->ring = ce->ring; rq->timeline = tl; - GEM_BUG_ON(rq->timeline == &engine->timeline); rq->hwsp_seqno = tl->hwsp_seqno; rq->hwsp_cacheline = tl->hwsp_cacheline; rq->rcustate = get_state_synchronize_rcu(); /* acts as smp_mb() */ @@ -743,6 +674,10 @@ i915_request_alloc(struct intel_engine_cs *engine, struct i915_gem_context *ctx) rq->batch = NULL; rq->capture_list = NULL; rq->waitboost = false; + rq->execution_mask = ALL_ENGINES; + + INIT_LIST_HEAD(&rq->active_list); + INIT_LIST_HEAD(&rq->execute_cb); /* * Reserve space in the ring buffer for all the commands required to @@ -756,7 +691,8 @@ i915_request_alloc(struct intel_engine_cs *engine, struct i915_gem_context *ctx) * around inside i915_request_add() there is sufficient space at * the beginning of the ring as well. */ - rq->reserved_space = 2 * engine->emit_fini_breadcrumb_dw * sizeof(u32); + rq->reserved_space = + 2 * rq->engine->emit_fini_breadcrumb_dw * sizeof(u32); /* * Record the position of the start of the request so that @@ -766,20 +702,13 @@ i915_request_alloc(struct intel_engine_cs *engine, struct i915_gem_context *ctx) */ rq->head = rq->ring->emit; - ret = engine->request_alloc(rq); + ret = rq->engine->request_alloc(rq); if (ret) goto err_unwind; - /* Keep a second pin for the dual retirement along engine and ring */ - __intel_context_pin(ce); - rq->infix = rq->ring->emit; /* end of header; start of user payload */ - /* Check that we didn't interrupt ourselves with a new request */ - lockdep_assert_held(&rq->timeline->mutex); - GEM_BUG_ON(rq->timeline->seqno != rq->fence.seqno); - rq->cookie = lockdep_pin_lock(&rq->timeline->mutex); - + intel_context_mark_active(ce); return rq; err_unwind: @@ -793,12 +722,41 @@ err_unwind: err_free: kmem_cache_free(global.slab_requests, rq); err_unreserve: - mutex_unlock(&ce->ring->timeline->mutex); - unreserve_gt(i915); intel_context_unpin(ce); return ERR_PTR(ret); } +struct i915_request * +i915_request_create(struct intel_context *ce) +{ + struct i915_request *rq; + int err; + + err = intel_context_timeline_lock(ce); + if (err) + return ERR_PTR(err); + + /* Move our oldest request to the slab-cache (if not in use!) */ + rq = list_first_entry(&ce->ring->request_list, typeof(*rq), ring_link); + if (!list_is_last(&rq->ring_link, &ce->ring->request_list)) + i915_request_retire(rq); + + intel_context_enter(ce); + rq = __i915_request_create(ce, GFP_KERNEL); + intel_context_exit(ce); /* active reference transferred to request */ + if (IS_ERR(rq)) + goto err_unlock; + + /* Check that we do not interrupt ourselves with a new request */ + rq->cookie = lockdep_pin_lock(&ce->ring->timeline->mutex); + + return rq; + +err_unlock: + intel_context_timeline_unlock(ce); + return rq; +} + static int i915_request_await_start(struct i915_request *rq, struct i915_request *signal) { @@ -829,7 +787,7 @@ already_busywaiting(struct i915_request *rq) * * See the are-we-too-late? check in __i915_request_submit(). */ - return rq->sched.semaphores | rq->hw_context->saturated; + return rq->sched.semaphores | rq->engine->saturated; } static int @@ -854,13 +812,13 @@ emit_semaphore_wait(struct i915_request *to, if (err < 0) return err; - /* We need to pin the signaler's HWSP until we are finished reading. */ - err = i915_timeline_read_hwsp(from, to, &hwsp_offset); + /* Only submit our spinner after the signaler is running! */ + err = __i915_request_await_execution(to, from, NULL, gfp); if (err) return err; - /* Only submit our spinner after the signaler is running! */ - err = i915_request_await_execution(to, from, gfp); + /* We need to pin the signaler's HWSP until we are finished reading. */ + err = i915_timeline_read_hwsp(from, to, &hwsp_offset); if (err) return err; @@ -991,6 +949,52 @@ i915_request_await_dma_fence(struct i915_request *rq, struct dma_fence *fence) return 0; } +int +i915_request_await_execution(struct i915_request *rq, + struct dma_fence *fence, + void (*hook)(struct i915_request *rq, + struct dma_fence *signal)) +{ + struct dma_fence **child = &fence; + unsigned int nchild = 1; + int ret; + + if (dma_fence_is_array(fence)) { + struct dma_fence_array *array = to_dma_fence_array(fence); + + /* XXX Error for signal-on-any fence arrays */ + + child = array->fences; + nchild = array->num_fences; + GEM_BUG_ON(!nchild); + } + + do { + fence = *child++; + if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags)) + continue; + + /* + * We don't squash repeated fence dependencies here as we + * want to run our callback in all cases. + */ + + if (dma_fence_is_i915(fence)) + ret = __i915_request_await_execution(rq, + to_request(fence), + hook, + I915_FENCE_GFP); + else + ret = i915_sw_fence_await_dma_fence(&rq->submit, fence, + I915_FENCE_TIMEOUT, + GFP_KERNEL); + if (ret < 0) + return ret; + } while (--nchild); + + return 0; +} + /** * i915_request_await_object - set this request to (async) wait upon a bo * @to: request we are wishing to use @@ -1023,7 +1027,7 @@ i915_request_await_object(struct i915_request *to, struct dma_fence **shared; unsigned int count, i; - ret = reservation_object_get_fences_rcu(obj->resv, + ret = reservation_object_get_fences_rcu(obj->base.resv, &excl, &count, &shared); if (ret) return ret; @@ -1040,7 +1044,7 @@ i915_request_await_object(struct i915_request *to, dma_fence_put(shared[i]); kfree(shared); } else { - excl = reservation_object_get_excl_rcu(obj->resv); + excl = reservation_object_get_excl_rcu(obj->base.resv); } if (excl) { @@ -1100,8 +1104,7 @@ __i915_request_add_to_timeline(struct i915_request *rq) * precludes optimising to use semaphores serialisation of a single * timeline across engines. */ - prev = i915_active_request_raw(&timeline->last_request, - &rq->i915->drm.struct_mutex); + prev = rcu_dereference_protected(timeline->last_request.request, 1); if (prev && !i915_request_completed(prev)) { if (is_power_of_2(prev->engine->mask | rq->engine->mask)) i915_sw_fence_await_sw_fence(&rq->submit, @@ -1118,10 +1121,13 @@ __i915_request_add_to_timeline(struct i915_request *rq) 0); } - spin_lock_irq(&timeline->lock); list_add_tail(&rq->link, &timeline->requests); - spin_unlock_irq(&timeline->lock); + /* + * Make sure that no request gazumped us - if it was allocated after + * our i915_request_alloc() and called __i915_request_add() before + * us, the timeline will hold its seqno which is later than ours. + */ GEM_BUG_ON(timeline->seqno != rq->fence.seqno); __i915_active_request_set(&timeline->last_request, rq); @@ -1133,36 +1139,23 @@ __i915_request_add_to_timeline(struct i915_request *rq) * request is not being tracked for completion but the work itself is * going to happen on the hardware. This would be a Bad Thing(tm). */ -void i915_request_add(struct i915_request *request) +struct i915_request *__i915_request_commit(struct i915_request *rq) { - struct intel_engine_cs *engine = request->engine; - struct i915_timeline *timeline = request->timeline; - struct intel_ring *ring = request->ring; + struct intel_engine_cs *engine = rq->engine; + struct intel_ring *ring = rq->ring; struct i915_request *prev; u32 *cs; GEM_TRACE("%s fence %llx:%lld\n", - engine->name, request->fence.context, request->fence.seqno); - - lockdep_assert_held(&request->timeline->mutex); - lockdep_unpin_lock(&request->timeline->mutex, request->cookie); - - trace_i915_request_add(request); - - /* - * Make sure that no request gazumped us - if it was allocated after - * our i915_request_alloc() and called __i915_request_add() before - * us, the timeline will hold its seqno which is later than ours. - */ - GEM_BUG_ON(timeline->seqno != request->fence.seqno); + engine->name, rq->fence.context, rq->fence.seqno); /* * To ensure that this call will not fail, space for its emissions * should already have been reserved in the ring buffer. Let the ring * know that it is time to use that space up. */ - GEM_BUG_ON(request->reserved_space > request->ring->space); - request->reserved_space = 0; + GEM_BUG_ON(rq->reserved_space > ring->space); + rq->reserved_space = 0; /* * Record the position of the start of the breadcrumb so that @@ -1170,17 +1163,16 @@ void i915_request_add(struct i915_request *request) * GPU processing the request, we never over-estimate the * position of the ring's HEAD. */ - cs = intel_ring_begin(request, engine->emit_fini_breadcrumb_dw); + cs = intel_ring_begin(rq, engine->emit_fini_breadcrumb_dw); GEM_BUG_ON(IS_ERR(cs)); - request->postfix = intel_ring_offset(request, cs); + rq->postfix = intel_ring_offset(rq, cs); - prev = __i915_request_add_to_timeline(request); + prev = __i915_request_add_to_timeline(rq); - list_add_tail(&request->ring_link, &ring->request_list); - if (list_is_first(&request->ring_link, &ring->request_list)) - list_add(&ring->active_link, &request->i915->gt.active_rings); - request->i915->gt.active_engines |= request->engine->mask; - request->emitted_jiffies = jiffies; + list_add_tail(&rq->ring_link, &ring->request_list); + if (list_is_first(&rq->ring_link, &ring->request_list)) + list_add(&ring->active_link, &rq->i915->gt.active_rings); + rq->emitted_jiffies = jiffies; /* * Let the backend know a new request has arrived that may need @@ -1194,10 +1186,10 @@ void i915_request_add(struct i915_request *request) * run at the earliest possible convenience. */ local_bh_disable(); - i915_sw_fence_commit(&request->semaphore); + i915_sw_fence_commit(&rq->semaphore); rcu_read_lock(); /* RCU serialisation for set-wedged protection */ if (engine->schedule) { - struct i915_sched_attr attr = request->gem_context->sched; + struct i915_sched_attr attr = rq->gem_context->sched; /* * Boost actual workloads past semaphores! @@ -1211,7 +1203,7 @@ void i915_request_add(struct i915_request *request) * far in the distance past over useful work, we keep a history * of any semaphore use along our dependency chain. */ - if (!(request->sched.flags & I915_SCHED_HAS_SEMAPHORE_CHAIN)) + if (!(rq->sched.flags & I915_SCHED_HAS_SEMAPHORE_CHAIN)) attr.priority |= I915_PRIORITY_NOSEMAPHORE; /* @@ -1220,15 +1212,29 @@ void i915_request_add(struct i915_request *request) * Allow interactive/synchronous clients to jump ahead of * the bulk clients. (FQ_CODEL) */ - if (list_empty(&request->sched.signalers_list)) + if (list_empty(&rq->sched.signalers_list)) attr.priority |= I915_PRIORITY_WAIT; - engine->schedule(request, &attr); + engine->schedule(rq, &attr); } rcu_read_unlock(); - i915_sw_fence_commit(&request->submit); + i915_sw_fence_commit(&rq->submit); local_bh_enable(); /* Kick the execlists tasklet if just scheduled */ + return prev; +} + +void i915_request_add(struct i915_request *rq) +{ + struct i915_request *prev; + + lockdep_assert_held(&rq->timeline->mutex); + lockdep_unpin_lock(&rq->timeline->mutex, rq->cookie); + + trace_i915_request_add(rq); + + prev = __i915_request_commit(rq); + /* * In typical scenarios, we do not expect the previous request on * the timeline to be still tracked by timeline->last_request if it @@ -1249,7 +1255,7 @@ void i915_request_add(struct i915_request *request) if (prev && i915_request_completed(prev)) i915_request_retire_upto(prev); - mutex_unlock(&request->timeline->mutex); + mutex_unlock(&rq->timeline->mutex); } static unsigned long local_clock_us(unsigned int *cpu) @@ -1354,10 +1360,6 @@ static void request_wait_wake(struct dma_fence *fence, struct dma_fence_cb *cb) * maximum of @timeout jiffies (with MAX_SCHEDULE_TIMEOUT implying an * unbounded wait). * - * If the caller holds the struct_mutex, the caller must pass I915_WAIT_LOCKED - * in via the flags, and vice versa if the struct_mutex is not held, the caller - * must not specify that the wait is locked. - * * Returns the remaining time (in jiffies) if the request completed, which may * be zero or -ETIME if the request is unfinished after the timeout expires. * May return -EINTR is called with I915_WAIT_INTERRUPTIBLE and a signal is @@ -1374,7 +1376,7 @@ long i915_request_wait(struct i915_request *rq, might_sleep(); GEM_BUG_ON(timeout < 0); - if (i915_request_completed(rq)) + if (dma_fence_is_signaled(&rq->fence)) return timeout; if (!timeout) @@ -1382,9 +1384,43 @@ long i915_request_wait(struct i915_request *rq, trace_i915_request_wait_begin(rq, flags); - /* Optimistic short spin before touching IRQs */ - if (__i915_spin_request(rq, state, 5)) + /* + * We must never wait on the GPU while holding a lock as we + * may need to perform a GPU reset. So while we don't need to + * serialise wait/reset with an explicit lock, we do want + * lockdep to detect potential dependency cycles. + */ + mutex_acquire(&rq->i915->gpu_error.wedge_mutex.dep_map, + 0, 0, _THIS_IP_); + + /* + * Optimistic spin before touching IRQs. + * + * We may use a rather large value here to offset the penalty of + * switching away from the active task. Frequently, the client will + * wait upon an old swapbuffer to throttle itself to remain within a + * frame of the gpu. If the client is running in lockstep with the gpu, + * then it should not be waiting long at all, and a sleep now will incur + * extra scheduler latency in producing the next frame. To try to + * avoid adding the cost of enabling/disabling the interrupt to the + * short wait, we first spin to see if the request would have completed + * in the time taken to setup the interrupt. + * + * We need upto 5us to enable the irq, and upto 20us to hide the + * scheduler latency of a context switch, ignoring the secondary + * impacts from a context switch such as cache eviction. + * + * The scheme used for low-latency IO is called "hybrid interrupt + * polling". The suggestion there is to sleep until just before you + * expect to be woken by the device interrupt and then poll for its + * completion. That requires having a good predictor for the request + * duration, which we currently lack. + */ + if (CONFIG_DRM_I915_SPIN_REQUEST && + __i915_spin_request(rq, state, CONFIG_DRM_I915_SPIN_REQUEST)) { + dma_fence_signal(&rq->fence); goto out; + } /* * This client is about to stall waiting for the GPU. In many cases @@ -1401,9 +1437,7 @@ long i915_request_wait(struct i915_request *rq, if (flags & I915_WAIT_PRIORITY) { if (!i915_request_started(rq) && INTEL_GEN(rq->i915) >= 6) gen6_rps_boost(rq); - local_bh_disable(); /* suspend tasklets for reprioritisation */ i915_schedule_bump_priority(rq, I915_PRIORITY_WAIT); - local_bh_enable(); /* kick tasklets en masse */ } wait.tsk = current; @@ -1433,25 +1467,25 @@ long i915_request_wait(struct i915_request *rq, dma_fence_remove_callback(&rq->fence, &wait.cb); out: + mutex_release(&rq->i915->gpu_error.wedge_mutex.dep_map, 0, _THIS_IP_); trace_i915_request_wait_end(rq); return timeout; } -void i915_retire_requests(struct drm_i915_private *i915) +bool i915_retire_requests(struct drm_i915_private *i915) { struct intel_ring *ring, *tmp; lockdep_assert_held(&i915->drm.struct_mutex); - if (!i915->gt.active_requests) - return; - list_for_each_entry_safe(ring, tmp, &i915->gt.active_rings, active_link) { intel_ring_get(ring); /* last rq holds reference! */ ring_retire_requests(ring); intel_ring_put(ring); } + + return !list_empty(&i915->gt.active_rings); } #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST) |