From 672e7b7c1849c904b2c55185906b3940843c55c6 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Wed, 19 Nov 2014 09:47:19 +0000 Subject: [PATCH] drm/i915: Don't continually defer the hangcheck With multiple rings, we may continue to render on the blitter whilst executing an infinite shader on the render ring. As we currently, rearm the timer with each execbuf, in this scenario the hangcheck will never fire and we will never detect the lockup on the render ring. Instead, only arm the timer once per hangcheck, so that hangcheck runs more frequently. v2: Rearrange code to avoid triggering a BUG_ON in add_timer from softirq context. Testcase: igt/gem_reset_stats/defer-hangcheck* Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=86225 Signed-off-by: Chris Wilson Cc: Mika Kuoppala Reviewed-by: Mika Kuoppala Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/i915_irq.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index 5e5d3f709f0f..e298518c944e 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -988,7 +988,6 @@ static void notify_ring(struct drm_device *dev, trace_i915_gem_request_complete(ring); wake_up_all(&ring->irq_queue); - i915_queue_hangcheck(dev); } static u32 vlv_c0_residency(struct drm_i915_private *dev_priv, @@ -3041,11 +3040,15 @@ static void i915_hangcheck_elapsed(unsigned long data) void i915_queue_hangcheck(struct drm_device *dev) { struct drm_i915_private *dev_priv = dev->dev_private; + struct timer_list *timer = &dev_priv->gpu_error.hangcheck_timer; + if (!i915.enable_hangcheck) return; - mod_timer(&dev_priv->gpu_error.hangcheck_timer, - round_jiffies_up(jiffies + DRM_I915_HANGCHECK_JIFFIES)); + /* Don't continually defer the hangcheck, but make sure it is active */ + if (!timer_pending(timer)) + timer->expires = round_jiffies_up(jiffies + DRM_I915_HANGCHECK_JIFFIES); + mod_timer(timer, timer->expires); } static void ibx_irq_reset(struct drm_device *dev)