From e39d42fa7e8bdd1ae88da6c7acbe04d8a68f130f Mon Sep 17 00:00:00 2001 From: Tvrtko Ursulin Date: Thu, 28 Apr 2016 09:56:58 +0100 Subject: [PATCH] drm/i915: Stop tracking execlists retired requests With the previous patch having extended the pinned lifetime of contexts by referencing the previous context from the current request until the latter is retired (completed by the GPU), we can now remove usage of execlist retired queue entirely. This is because the above now guarantees that all execlist object access requirements are satisfied by this new tracking, and we can stop taking additional references and stop keeping request on the execlists retired queue. The latter was a source of significant scalability issues in the driver causing performance hits on some tests. Most dramatical of which was igt/gem_close_race which had run time in tens of minutes which is now reduced to tens of seconds. Signed-off-by: Tvrtko Ursulin Cc: Chris Wilson Reviewed-by: Chris Wilson Signed-off-by: Chris Wilson Link: http://patchwork.freedesktop.org/patch/msgid/1461833819-3991-24-git-send-email-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_gem.c | 10 +-------- drivers/gpu/drm/i915/intel_lrc.c | 39 ++++++++++++--------------------- drivers/gpu/drm/i915/intel_lrc.h | 2 +- drivers/gpu/drm/i915/intel_ringbuffer.h | 1 - 4 files changed, 16 insertions(+), 36 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 72cd084..411201f 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -2874,13 +2874,7 @@ static void i915_gem_reset_engine_cleanup(struct drm_i915_private *dev_priv, /* Ensure irq handler finishes or is cancelled. */ tasklet_kill(&engine->irq_tasklet); - spin_lock_bh(&engine->execlist_lock); - /* list_splice_tail_init checks for empty lists */ - list_splice_tail_init(&engine->execlist_queue, - &engine->execlist_retired_req_list); - spin_unlock_bh(&engine->execlist_lock); - - intel_execlists_retire_requests(engine); + intel_execlists_cancel_requests(engine); } /* @@ -3004,8 +2998,6 @@ i915_gem_retire_requests(struct drm_device *dev) spin_lock_bh(&engine->execlist_lock); idle &= list_empty(&engine->execlist_queue); spin_unlock_bh(&engine->execlist_lock); - - intel_execlists_retire_requests(engine); } } diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c index dc25cfe..874c251 100644 --- a/drivers/gpu/drm/i915/intel_lrc.c +++ b/drivers/gpu/drm/i915/intel_lrc.c @@ -435,8 +435,8 @@ static void execlists_context_unqueue(struct intel_engine_cs *engine) /* Same ctx: ignore first request, as second request * will update tail past first request's workload */ cursor->elsp_submitted = req0->elsp_submitted; - list_move_tail(&req0->execlist_link, - &engine->execlist_retired_req_list); + list_del(&req0->execlist_link); + i915_gem_request_unreference(req0); req0 = cursor; } else { req1 = cursor; @@ -468,7 +468,7 @@ static void execlists_context_unqueue(struct intel_engine_cs *engine) } static unsigned int -execlists_check_remove_request(struct intel_engine_cs *engine, u32 request_id) +execlists_check_remove_request(struct intel_engine_cs *engine, u32 ctx_id) { struct drm_i915_gem_request *head_req; @@ -478,19 +478,16 @@ execlists_check_remove_request(struct intel_engine_cs *engine, u32 request_id) struct drm_i915_gem_request, execlist_link); - if (!head_req) - return 0; - - if (unlikely(head_req->ctx_hw_id != request_id)) - return 0; + if (WARN_ON(!head_req || (head_req->ctx_hw_id != ctx_id))) + return 0; WARN(head_req->elsp_submitted == 0, "Never submitted head request\n"); if (--head_req->elsp_submitted > 0) return 0; - list_move_tail(&head_req->execlist_link, - &engine->execlist_retired_req_list); + list_del(&head_req->execlist_link); + i915_gem_request_unreference(head_req); return 1; } @@ -594,9 +591,6 @@ static void execlists_context_queue(struct drm_i915_gem_request *request) struct drm_i915_gem_request *cursor; int num_elements = 0; - intel_lr_context_pin(request->ctx, request->engine); - i915_gem_request_reference(request); - spin_lock_bh(&engine->execlist_lock); list_for_each_entry(cursor, &engine->execlist_queue, execlist_link) @@ -613,11 +607,12 @@ static void execlists_context_queue(struct drm_i915_gem_request *request) if (request->ctx == tail_req->ctx) { WARN(tail_req->elsp_submitted != 0, "More than 2 already-submitted reqs queued\n"); - list_move_tail(&tail_req->execlist_link, - &engine->execlist_retired_req_list); + list_del(&tail_req->execlist_link); + i915_gem_request_unreference(tail_req); } } + i915_gem_request_reference(request); list_add_tail(&request->execlist_link, &engine->execlist_queue); request->ctx_hw_id = request->ctx->hw_id; if (num_elements == 0) @@ -883,23 +878,18 @@ int intel_execlists_submission(struct i915_execbuffer_params *params, return 0; } -void intel_execlists_retire_requests(struct intel_engine_cs *engine) +void intel_execlists_cancel_requests(struct intel_engine_cs *engine) { struct drm_i915_gem_request *req, *tmp; - struct list_head retired_list; + LIST_HEAD(cancel_list); WARN_ON(!mutex_is_locked(&engine->dev->struct_mutex)); - if (list_empty(&engine->execlist_retired_req_list)) - return; - INIT_LIST_HEAD(&retired_list); spin_lock_bh(&engine->execlist_lock); - list_replace_init(&engine->execlist_retired_req_list, &retired_list); + list_replace_init(&engine->execlist_queue, &cancel_list); spin_unlock_bh(&engine->execlist_lock); - list_for_each_entry_safe(req, tmp, &retired_list, execlist_link) { - intel_lr_context_unpin(req->ctx, engine); - + list_for_each_entry_safe(req, tmp, &cancel_list, execlist_link) { list_del(&req->execlist_link); i915_gem_request_unreference(req); } @@ -1993,7 +1983,6 @@ logical_ring_init(struct drm_device *dev, struct intel_engine_cs *engine) INIT_LIST_HEAD(&engine->buffers); INIT_LIST_HEAD(&engine->execlist_queue); - INIT_LIST_HEAD(&engine->execlist_retired_req_list); spin_lock_init(&engine->execlist_lock); tasklet_init(&engine->irq_tasklet, diff --git a/drivers/gpu/drm/i915/intel_lrc.h b/drivers/gpu/drm/i915/intel_lrc.h index 28ff324..229b8a9 100644 --- a/drivers/gpu/drm/i915/intel_lrc.h +++ b/drivers/gpu/drm/i915/intel_lrc.h @@ -118,6 +118,6 @@ int intel_execlists_submission(struct i915_execbuffer_params *params, struct drm_i915_gem_execbuffer2 *args, struct list_head *vmas); -void intel_execlists_retire_requests(struct intel_engine_cs *engine); +void intel_execlists_cancel_requests(struct intel_engine_cs *engine); #endif /* _INTEL_LRC_H_ */ diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h index 038914c..7023e88 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.h +++ b/drivers/gpu/drm/i915/intel_ringbuffer.h @@ -266,7 +266,6 @@ struct intel_engine_cs { struct tasklet_struct irq_tasklet; spinlock_t execlist_lock; /* used inside tasklet, use spin_lock_bh */ struct list_head execlist_queue; - struct list_head execlist_retired_req_list; unsigned int fw_domains; unsigned int next_context_status_buffer; unsigned int idle_lite_restore_wa; -- 2.7.4