Quoting Mika Kuoppala (2017-09-07 14:22:21) > Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> writes: > > > If the user bypasses i915 and accesses mmio directly, that easily > > confuses our automatic mmio debugging (any error we then detect is > > likely to be as a result of the user). Since we expect userspace to open > > debugfs/i915_forcewake_user if i915.ko is loaded and they want mmio > > access, that makes the opportune time to disable our debugging for > > duration of the bypass. > > > > References: https://bugs.freedesktop.org/show_bug.cgi?id=102543 > > Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > > Cc: Mika Kuoppala <mika.kuoppala@xxxxxxxxxxxxxxx> > > --- > > drivers/gpu/drm/i915/i915_debugfs.c | 32 ++++++++++++++++++++++++++++++-- > > drivers/gpu/drm/i915/intel_uncore.h | 7 +++++++ > > 2 files changed, 37 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c > > index 48572b157222..d63b3c5c2f83 100644 > > --- a/drivers/gpu/drm/i915/i915_debugfs.c > > +++ b/drivers/gpu/drm/i915/i915_debugfs.c > > @@ -4679,7 +4679,21 @@ static int i915_forcewake_open(struct inode *inode, struct file *file) > > return 0; > > > > intel_runtime_pm_get(dev_priv); > > - intel_uncore_forcewake_get(dev_priv, FORCEWAKE_ALL); > > + > > + spin_lock_irq(&dev_priv->uncore.lock); > > + if (!dev_priv->uncore.user_forcewake.count++) { > > + intel_uncore_forcewake_get__locked(dev_priv, FORCEWAKE_ALL); > > + > > + /* Save and disable mmio debugging for the user bypass */ > > + dev_priv->uncore.user_forcewake.saved_mmio_check = > > + dev_priv->uncore.unclaimed_mmio_check; > > + dev_priv->uncore.user_forcewake.saved_mmio_debug = > > + i915.mmio_debug; > > + > > + dev_priv->uncore.unclaimed_mmio_check = 0; > > + i915.mmio_debug = 0; > > + } > > + spin_unlock_irq(&dev_priv->uncore.lock); > > Just pondering if this should be in intel_uncore.c as a > user_mmio_bypass_on/off(). But not insisting. Good call. Fwiw, since CI didn't report the improvement, this did shut up tools_tests: [ 37.601863] i915 0000:00:02.0: Unclaimed mmio occurred during user acess Ah better fix the spelling as well. -Chris _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
