Tvrtko Ursulin 9f473ecfe7 drm/i915/pmu: Do not assume fixed hrtimer period ... As Chris has discovered on his Ivybridge, and later automated test runs have confirmed, on most of our platforms hrtimer faced with heavy GPU load can occasionally become sufficiently imprecise to affect PMU sampling calculations. This means we cannot assume sampling frequency is what we asked for, but we need to measure the interval ourselves. This patch is similar to Chris' original proposal for per-engine counters, but instead of introducing a new set to work around the problem with frequency sampling, it swaps around the way internal frequency accounting is done. Instead of accumulating current frequency and dividing by sampling frequency on readout, it accumulates frequency scaled by each period. v2: * Typo in commit message, comment on period calculation and USEC_PER_SEC. (Chris Wilson) Testcase: igt/perf_pmu/*busy* # snb, ivb, hsw Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Suggested-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20180605140253.3541-1-tvrtko.ursulin@linux.intel.com		2018-06-05 16:45:01 +01:00
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drm	drm/i915/pmu: Do not assume fixed hrtimer period	2018-06-05 16:45:01 +01:00
host1x
ipu-v3	gpu: ipu-v3: prg: avoid possible array underflow	2018-03-15 17:52:08 +01:00
vga	vga_switcheroo: Let HDA autosuspend on mux change	2018-03-13 22:58:49 +01:00
Makefile