Tvrtko Ursulin b2f78cda26 drm/i915/pmu: Fix PMU enable vs execlists tasklet race ... Commit 99e48bf98d ("drm/i915: Lock out execlist tasklet while peeking inside for busy-stats") added a tasklet_disable call in busy stats enabling, but we failed to understand that the PMU enable callback runs as an hard IRQ (IPI). Consequence of this is that the PMU enable callback can interrupt the execlists tasklet, and will then deadlock when it calls intel_engine_stats_enable->tasklet_disable. To fix this, I realized it is possible to move the engine stats enablement and disablement to PMU event init and destroy hooks. This allows for much simpler implementation since those hooks run in normal context (can sleep). v2: Extract engine_event_destroy. (Chris Wilson) Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Fixes: 99e48bf98d ("drm/i915: Lock out execlist tasklet while peeking inside for busy-stats") Testcase: igt/perf_pmu/enable-race-* Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: intel-gfx@lists.freedesktop.org Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20180205093448.13877-1-tvrtko.ursulin@linux.intel.com		2018-02-06 11:21:27 +00:00
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drm	drm/i915/pmu: Fix PMU enable vs execlists tasklet race	2018-02-06 11:21:27 +00:00
host1x	gpu: host1x: Use IOMMU groups	2017-12-21 14:52:36 +01:00
ipu-v3	gpu: ipu-v3: allow to build with COMPILE_TEST	2017-12-19 12:49:11 +01:00
vga	vgaarb: Factor out EFI and fallback default device selection	2017-10-18 10:04:56 +02:00
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