While user space has control over the scheduling priority of its page flipping thread, the corresponding work the driver schedules for MMIO flips always runs from the generic system workqueue which has some scheduling overhead due it being CPU bound. This would hinder an application that wants more stringent guarantees over flip timing (to avoid missing a flip at the next frame count). Fix this by scheduling the work from the unbound system workqueue which provides for minimal scheduling latency. v2: - Use an unbound workqueue instead of a high-prio one. (Tvrtko, Chris) v3: - Use the system unbound wq instead of a dedicated one. (Maarten) Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97775 Testcase: igt/kms_cursor_legacy CC: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> CC: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx> CC: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx> Signed-off-by: Imre Deak <imre.deak@xxxxxxxxx> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx> (v1) --- drivers/gpu/drm/i915/intel_display.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 7bb7874..8da9f3c 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -12266,7 +12266,7 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc, work->flip_queued_req = i915_gem_active_get(&obj->last_write, &obj->base.dev->struct_mutex); - schedule_work(&work->mmio_work); + queue_work(system_unbound_wq, &work->mmio_work); } else { request = i915_gem_request_alloc(engine, engine->last_context); if (IS_ERR(request)) { -- 2.5.0 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
