drm/i915: Disable hangcheck when wedged

If the gpu reset fails and the machine is terminally wedged, further
hangchecks achieve nothing but noise. Disable them, with a corollary
that we re-enable hangchecking after a successful GPU reset in case the
user is artificially bringing the machine back to life through the debug
interface.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161122144121.7379-2-chris@chris-wilson.co.uk

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index ff13503..b893e67 100644 (file)
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -1822,6 +1822,8 @@ void i915_reset(struct drm_i915_private *dev_priv)
                goto error;
        }
 
+       i915_queue_hangcheck(dev_priv);
+
 wakeup:
        wake_up_bit(&error->flags, I915_RESET_IN_PROGRESS);
        return;

diff --git a/drivers/gpu/drm/i915/intel_hangcheck.c b/drivers/gpu/drm/i915/intel_hangcheck.c
index c03db02..f05971f 100644 (file)
--- a/drivers/gpu/drm/i915/intel_hangcheck.c
+++ b/drivers/gpu/drm/i915/intel_hangcheck.c
@@ -434,6 +434,9 @@ static void i915_hangcheck_elapsed(struct work_struct *work)
        if (!READ_ONCE(dev_priv->gt.awake))
                return;
 
+       if (i915_terminally_wedged(&dev_priv->gpu_error))
+               return;
+
        /* As enabling the GPU requires fairly extensive mmio access,
         * periodically arm the mmio checker to see if we are triggering
         * any invalid access.