If we get the final value of zero as a count of free entries available, we will underflow our own fifo_count and then it will take a long time before we check things again. Admittedly we are in trouble already if we get into this situation, but prevent the underflow by checking against zero before decreasing fifo_count. Signed-off-by: Mika Kuoppala <mika.kuoppala@xxxxxxxxx> --- drivers/gpu/drm/i915/intel_uncore.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c index 76dc185..159f8ab 100644 --- a/drivers/gpu/drm/i915/intel_uncore.c +++ b/drivers/gpu/drm/i915/intel_uncore.c @@ -174,7 +174,7 @@ static int __gen6_gt_wait_for_fifo(struct drm_i915_private *dev_priv) } if (WARN_ON(loop < 0 && fifo <= GT_FIFO_NUM_RESERVED_ENTRIES)) ++ret; - dev_priv->uncore.fifo_count = fifo; + dev_priv->uncore.fifo_count = fifo ?: 1; } dev_priv->uncore.fifo_count--; -- 1.7.9.5 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
