From: Chris Wilson Date: Fri, 31 Jul 2020 15:48:32 +0000 (+0100) Subject: drm/i915/gt: Replace intel_engine_transfer_stale_breadcrumbs X-Git-Tag: v5.15~2259^2~8^2~105 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=2854d866327a390540c71ca3f76ce516ae7af66f;p=platform%2Fkernel%2Flinux-starfive.git drm/i915/gt: Replace intel_engine_transfer_stale_breadcrumbs After staring at the breadcrumb enabling/cancellation and coming to the conclusion that the cause of the mysterious stale breadcrumbs must the act of submitting a completed requests, we can then redirect those completed requests onto a dedicated signaled_list at the time of construction and so eliminate intel_engine_transfer_stale_breadcrumbs(). Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin Reviewed-by: Tvrtko Ursulin Link: https://patchwork.freedesktop.org/patch/msgid/20200731154834.8378-2-chris@chris-wilson.co.uk Signed-off-by: Rodrigo Vivi Signed-off-by: Joonas Lahtinen --- diff --git a/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c b/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c index 3d211a0..fbdc465 100644 --- a/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c +++ b/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c @@ -142,16 +142,16 @@ static void add_retire(struct intel_breadcrumbs *b, struct intel_timeline *tl) intel_engine_add_retire(engine, tl); } -static void __signal_request(struct i915_request *rq, struct list_head *signals) +static bool __signal_request(struct i915_request *rq, struct list_head *signals) { - GEM_BUG_ON(!test_bit(I915_FENCE_FLAG_SIGNAL, &rq->fence.flags)); clear_bit(I915_FENCE_FLAG_SIGNAL, &rq->fence.flags); if (!__dma_fence_signal(&rq->fence)) - return; + return false; i915_request_get(rq); list_add_tail(&rq->signal_link, signals); + return true; } static void signal_irq_work(struct irq_work *work) @@ -278,32 +278,6 @@ void intel_engine_reset_breadcrumbs(struct intel_engine_cs *engine) spin_unlock_irqrestore(&b->irq_lock, flags); } -void intel_engine_transfer_stale_breadcrumbs(struct intel_engine_cs *engine, - struct intel_context *ce) -{ - struct intel_breadcrumbs *b = &engine->breadcrumbs; - unsigned long flags; - - spin_lock_irqsave(&b->irq_lock, flags); - if (!list_empty(&ce->signals)) { - struct i915_request *rq, *next; - - /* Queue for executing the signal callbacks in the irq_work */ - list_for_each_entry_safe(rq, next, &ce->signals, signal_link) { - GEM_BUG_ON(rq->engine != engine); - GEM_BUG_ON(!__request_completed(rq)); - - __signal_request(rq, &b->signaled_requests); - } - - INIT_LIST_HEAD(&ce->signals); - list_del_init(&ce->signal_link); - - irq_work_queue(&b->irq_work); - } - spin_unlock_irqrestore(&b->irq_lock, flags); -} - void intel_engine_fini_breadcrumbs(struct intel_engine_cs *engine) { } @@ -317,6 +291,17 @@ static void insert_breadcrumb(struct i915_request *rq, if (test_bit(I915_FENCE_FLAG_SIGNAL, &rq->fence.flags)) return; + /* + * If the request is already completed, we can transfer it + * straight onto a signaled list, and queue the irq worker for + * its signal completion. + */ + if (__request_completed(rq)) { + if (__signal_request(rq, &b->signaled_requests)) + irq_work_queue(&b->irq_work); + return; + } + __intel_breadcrumbs_arm_irq(b); /* @@ -344,8 +329,11 @@ static void insert_breadcrumb(struct i915_request *rq, if (pos == &ce->signals) /* catch transitions from empty list */ list_move_tail(&ce->signal_link, &b->signalers); GEM_BUG_ON(!check_signal_order(ce, rq)); - set_bit(I915_FENCE_FLAG_SIGNAL, &rq->fence.flags); + + /* Check after attaching to irq, interrupt may have already fired. */ + if (__request_completed(rq)) + irq_work_queue(&b->irq_work); } bool i915_request_enable_breadcrumb(struct i915_request *rq) @@ -401,7 +389,7 @@ bool i915_request_enable_breadcrumb(struct i915_request *rq) spin_unlock(&b->irq_lock); - return !__request_completed(rq); + return true; } void i915_request_cancel_breadcrumb(struct i915_request *rq) diff --git a/drivers/gpu/drm/i915/gt/intel_engine.h b/drivers/gpu/drm/i915/gt/intel_engine.h index a9249a2..faf00a3 100644 --- a/drivers/gpu/drm/i915/gt/intel_engine.h +++ b/drivers/gpu/drm/i915/gt/intel_engine.h @@ -237,9 +237,6 @@ intel_engine_signal_breadcrumbs(struct intel_engine_cs *engine) void intel_engine_reset_breadcrumbs(struct intel_engine_cs *engine); void intel_engine_fini_breadcrumbs(struct intel_engine_cs *engine); -void intel_engine_transfer_stale_breadcrumbs(struct intel_engine_cs *engine, - struct intel_context *ce); - void intel_engine_print_breadcrumbs(struct intel_engine_cs *engine, struct drm_printer *p); diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c index 35174bf..17e7077 100644 --- a/drivers/gpu/drm/i915/gt/intel_lrc.c +++ b/drivers/gpu/drm/i915/gt/intel_lrc.c @@ -1805,18 +1805,6 @@ static bool virtual_matches(const struct virtual_engine *ve, return true; } -static void virtual_xfer_breadcrumbs(struct virtual_engine *ve) -{ - /* - * All the outstanding signals on ve->siblings[0] must have - * been completed, just pending the interrupt handler. As those - * signals still refer to the old sibling (via rq->engine), we must - * transfer those to the old irq_worker to keep our locking - * consistent. - */ - intel_engine_transfer_stale_breadcrumbs(ve->siblings[0], &ve->context); -} - #define for_each_waiter(p__, rq__) \ list_for_each_entry_lockless(p__, \ &(rq__)->sched.waiters_list, \ @@ -2267,9 +2255,6 @@ static void execlists_dequeue(struct intel_engine_cs *engine) virtual_update_register_offsets(regs, engine); - if (!list_empty(&ve->context.signals)) - virtual_xfer_breadcrumbs(ve); - /* * Move the bound engine to the top of the list * for future execution. We then kick this diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c index 956edbe..e9d5ce2 100644 --- a/drivers/gpu/drm/i915/i915_request.c +++ b/drivers/gpu/drm/i915/i915_request.c @@ -569,9 +569,8 @@ xfer: */ __notify_execute_cb(request); - if (test_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT, &request->fence.flags) && - !i915_request_enable_breadcrumb(request)) - intel_engine_signal_breadcrumbs(engine); + if (test_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT, &request->fence.flags)) + i915_request_enable_breadcrumb(request); return result; }