]> git.baikalelectronics.ru Git - kernel.git/commit
drm/i915: Defer final intel_wakeref_put to process context
authorChris Wilson <chris@chris-wilson.co.uk>
Thu, 8 Aug 2019 20:27:58 +0000 (21:27 +0100)
committerChris Wilson <chris@chris-wilson.co.uk>
Thu, 8 Aug 2019 20:28:51 +0000 (21:28 +0100)
commit729c7fcd9e3becf34ce30d18d1ae9d9aebd39b98
tree3ddd1c797a3fe06946dfd7d3dc91a916aa1f23d8
parent9ab96ad2615635249caec87548dfe93dc7580ce4
drm/i915: Defer final intel_wakeref_put to process context

As we need to acquire a mutex to serialise the final
intel_wakeref_put, we need to ensure that we are in process context at
that time. However, we want to allow operation on the intel_wakeref from
inside timer and other hardirq context, which means that need to defer
that final put to a workqueue.

Inside the final wakeref puts, we are safe to operate in any context, as
we are simply marking up the HW and state tracking for the potential
sleep. It's only the serialisation with the potential sleeping getting
that requires careful wait avoidance. This allows us to retain the
immediate processing as before (we only need to sleep over the same
races as the current mutex_lock).

v2: Add a selftest to ensure we exercise the code while lockdep watches.
v3: That test was extremely loud and complained about many things!
v4: Not a whale!

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111295
References: https://bugs.freedesktop.org/show_bug.cgi?id=111245
References: https://bugs.freedesktop.org/show_bug.cgi?id=111256
Fixes: 1a5d9086a40a ("drm/i915: Only recover active engines")
Fixes: 6ffc8758df85 ("drm/i915/pmu: Atomically acquire the gt_pm wakeref")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190808202758.10453-1-chris@chris-wilson.co.uk
16 files changed:
drivers/gpu/drm/i915/gem/i915_gem_pm.c
drivers/gpu/drm/i915/gt/intel_engine_cs.c
drivers/gpu/drm/i915/gt/intel_engine_pm.c
drivers/gpu/drm/i915/gt/intel_engine_pm.h
drivers/gpu/drm/i915/gt/intel_gt_pm.c
drivers/gpu/drm/i915/gt/intel_gt_pm.h
drivers/gpu/drm/i915/gt/intel_lrc.c
drivers/gpu/drm/i915/gt/selftest_engine.c [new file with mode: 0644]
drivers/gpu/drm/i915/gt/selftest_engine.h [new file with mode: 0644]
drivers/gpu/drm/i915/gt/selftest_engine_pm.c [new file with mode: 0644]
drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
drivers/gpu/drm/i915/i915_debugfs.c
drivers/gpu/drm/i915/i915_gem.c
drivers/gpu/drm/i915/intel_wakeref.c
drivers/gpu/drm/i915/intel_wakeref.h
drivers/gpu/drm/i915/selftests/i915_live_selftests.h