Commit 37db1470 authored Aug 04, 2016 by Chris Wilson

drm/i915: Disable waitboosting for a saturated engine

If the user floods the GPU with so many requests that the engine stalls
waiting for free space, don't automatically promote the GPU to maximum
frequencies. If the GPU really is saturated with work, it will migrate
to high clocks by itself, otherwise it is merely a user flooding us with
busy-work.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470293567-10811-20-git-send-email-chris@chris-wilson.co.uk

parent 7da844c5

drivers/gpu/drm/i915/intel_ringbuffer.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -2299,7 +2299,7 @@ static int wait_for_space(struct drm_i915_gem_request *req, int bytes)
		if (WARN_ON(&target->ring_link == &ring->request_list))
		return -ENOSPC;

		ret = __i915_wait_request(target, true, NULL, NULL);
		ret = __i915_wait_request(target, true, NULL, NO_WAITBOOST);
		if (ret)
		return ret;