diff mbox

drm/i915: Disable irqs across GPU reset

Message ID 20160930112545.18551-1-chris@chris-wilson.co.uk (mailing list archive)
State New, archived
Headers show

Commit Message

Chris Wilson Sept. 30, 2016, 11:25 a.m. UTC
Whilst we reset the GPU, we want to prevent execlists from submitting
new work (which it does via an interrupt handler). To achieve this we
disable the irq (and drain the irq tasklet) around the reset. When we
enable it again afters, the interrupt queue should be empty and we can
reinitialise from a known state without fear of the tasklet running
concurrently.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
---
 drivers/gpu/drm/i915/i915_drv.c | 19 +++++++++++++++++++
 drivers/gpu/drm/i915/i915_gem.c |  2 --
 2 files changed, 19 insertions(+), 2 deletions(-)

Comments

Mika Kuoppala Oct. 3, 2016, 12:42 p.m. UTC | #1
Chris Wilson <chris@chris-wilson.co.uk> writes:

> Whilst we reset the GPU, we want to prevent execlists from submitting
> new work (which it does via an interrupt handler). To achieve this we
> disable the irq (and drain the irq tasklet) around the reset. When we
> enable it again afters, the interrupt queue should be empty and we can
> reinitialise from a known state without fear of the tasklet running
> concurrently.
>
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Mika Kuoppala <mika.kuoppala@intel.com>

Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>

> ---
>  drivers/gpu/drm/i915/i915_drv.c | 19 +++++++++++++++++++
>  drivers/gpu/drm/i915/i915_gem.c |  2 --
>  2 files changed, 19 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
> index 31b2b6300d8d..7ce498898217 100644
> --- a/drivers/gpu/drm/i915/i915_drv.c
> +++ b/drivers/gpu/drm/i915/i915_drv.c
> @@ -1728,6 +1728,21 @@ int i915_resume_switcheroo(struct drm_device *dev)
>  	return i915_drm_resume(dev);
>  }
>  
> +static void disable_engines_irq(struct drm_i915_private *dev_priv)
> +{
> +	struct intel_engine_cs *engine;
> +
> +	/* Ensure irq handler finishes, and not run again. */
> +	disable_irq(dev_priv->drm.irq);
> +	for_each_engine(engine, dev_priv)
> +		tasklet_kill(&engine->irq_tasklet);
> +}
> +
> +static void enable_engines_irq(struct drm_i915_private *dev_priv)
> +{
> +	enable_irq(dev_priv->drm.irq);
> +}
> +
>  /**
>   * i915_reset - reset chip after a hang
>   * @dev: drm device to reset
> @@ -1761,7 +1776,11 @@ void i915_reset(struct drm_i915_private *dev_priv)
>  	error->reset_count++;
>  
>  	pr_notice("drm/i915: Resetting chip after gpu hang\n");
> +
> +	disable_engines_irq(dev_priv);
>  	ret = intel_gpu_reset(dev_priv, ALL_ENGINES);
> +	enable_engines_irq(dev_priv);
> +
>  	if (ret) {
>  		if (ret != -ENODEV)
>  			DRM_ERROR("Failed to reset chip: %i\n", ret);
> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> index 1418c1c522cb..0cae8acdf906 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -2581,8 +2581,6 @@ static void i915_gem_reset_engine(struct intel_engine_cs *engine)
>  	struct i915_gem_context *incomplete_ctx;
>  	bool ring_hung;
>  
> -	/* Ensure irq handler finishes, and not run again. */
> -	tasklet_kill(&engine->irq_tasklet);
>  	if (engine->irq_seqno_barrier)
>  		engine->irq_seqno_barrier(engine);
>  
> -- 
> 2.9.3
>
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/intel-gfx
diff mbox

Patch

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 31b2b6300d8d..7ce498898217 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -1728,6 +1728,21 @@  int i915_resume_switcheroo(struct drm_device *dev)
 	return i915_drm_resume(dev);
 }
 
+static void disable_engines_irq(struct drm_i915_private *dev_priv)
+{
+	struct intel_engine_cs *engine;
+
+	/* Ensure irq handler finishes, and not run again. */
+	disable_irq(dev_priv->drm.irq);
+	for_each_engine(engine, dev_priv)
+		tasklet_kill(&engine->irq_tasklet);
+}
+
+static void enable_engines_irq(struct drm_i915_private *dev_priv)
+{
+	enable_irq(dev_priv->drm.irq);
+}
+
 /**
  * i915_reset - reset chip after a hang
  * @dev: drm device to reset
@@ -1761,7 +1776,11 @@  void i915_reset(struct drm_i915_private *dev_priv)
 	error->reset_count++;
 
 	pr_notice("drm/i915: Resetting chip after gpu hang\n");
+
+	disable_engines_irq(dev_priv);
 	ret = intel_gpu_reset(dev_priv, ALL_ENGINES);
+	enable_engines_irq(dev_priv);
+
 	if (ret) {
 		if (ret != -ENODEV)
 			DRM_ERROR("Failed to reset chip: %i\n", ret);
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 1418c1c522cb..0cae8acdf906 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2581,8 +2581,6 @@  static void i915_gem_reset_engine(struct intel_engine_cs *engine)
 	struct i915_gem_context *incomplete_ctx;
 	bool ring_hung;
 
-	/* Ensure irq handler finishes, and not run again. */
-	tasklet_kill(&engine->irq_tasklet);
 	if (engine->irq_seqno_barrier)
 		engine->irq_seqno_barrier(engine);