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 <ch...@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursu...@linux.intel.com> Cc: Joonas Lahtinen <joonas.lahti...@linux.intel.com> Cc: Eero Tamminen <eero.t.tammi...@intel.com> Cc: Francisco Jerez <curroje...@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 ca25c53f8daa..694269e5b761 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)); @@ -1387,7 +1387,7 @@ 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 _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx
