[PATCH] drm/i915: Do not use iowait while waiting for the GPU

[Chris Wilson <chris@chris-wilson.co.uk>]

A recent trend for cpufreq is to boost the CPU frequencies for
iowaiters, in particularly to benefit high frequency I/O. We do the same
and boost the GPU clocks to try and minimise time spent waiting for the
GPU. However, as the igfx and CPU share the same TDP, boosting the CPU
frequency will result in the GPU being throttled and its frequency being
reduced. Thus declaring iowait negatively impacts on GPU throughput.

v2: Both sleeps!

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=107410
References: 52ccc4314293 ("cpufreq: intel_pstate: HWP boost performance on IO wakeup")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Eero Tamminen <eero.t.tamminen@intel.com>
Cc: Francisco Jerez <currojerez@riseup.net>
---
 drivers/gpu/drm/i915/i915_request.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
index 5c2c93cbab12..21950c1c3885 100644
--- a/drivers/gpu/drm/i915/i915_request.c
+++ b/drivers/gpu/drm/i915/i915_request.c
@@ -1330,7 +1330,7 @@ long i915_request_wait(struct i915_request *rq,
 			goto complete;
 		}
 
-		timeout = io_schedule_timeout(timeout);
+		timeout = schedule_timeout(timeout);
 	} while (1);
 
 	GEM_BUG_ON(!intel_wait_has_seqno(&wait));
@@ -1363,7 +1363,7 @@ long i915_request_wait(struct i915_request *rq,
 			break;
 		}
 
-		timeout = io_schedule_timeout(timeout);
+		timeout = schedule_timeout(timeout);
 
 		if (intel_wait_complete(&wait) &&
 		    intel_wait_check_request(&wait, rq))
-- 
2.18.0

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