diff mbox series

drm/i915/selftests: Hold rpm for unparking

Message ID 20180809063449.4474-1-chris@chris-wilson.co.uk (mailing list archive)
State New, archived
Headers show
Series drm/i915/selftests: Hold rpm for unparking | expand

Commit Message

Chris Wilson Aug. 9, 2018, 6:34 a.m. UTC
The call to i915_gem_unpark() checks that we hold a rpm wakeref before
taking a long term wakeref for i915->gt.awake. We should therefore make
sure we do hold the wakeref when directly calling unpark to disable
the retire worker.

Fixes: 932cac10c8fb ("drm/i915/selftests: Prevent background reaping of active objects")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
---
 .../gpu/drm/i915/selftests/i915_gem_object.c  | 20 +++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

Comments

Mika Kuoppala Aug. 9, 2018, 10:40 a.m. UTC | #1
Chris Wilson <chris@chris-wilson.co.uk> writes:

> The call to i915_gem_unpark() checks that we hold a rpm wakeref before
> taking a long term wakeref for i915->gt.awake. We should therefore make
> sure we do hold the wakeref when directly calling unpark to disable
> the retire worker.

We as a caller need to hold the rpm as i915_gem_unpark does 
intel_runtime_pm_get_noresume() ?

As I don't see any other checks before gt.awake being set.

-Mika

>
> Fixes: 932cac10c8fb ("drm/i915/selftests: Prevent background reaping of active objects")
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
> Cc: Matthew Auld <matthew.auld@intel.com>
> ---
>  .../gpu/drm/i915/selftests/i915_gem_object.c  | 20 +++++++++++++------
>  1 file changed, 14 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_object.c b/drivers/gpu/drm/i915/selftests/i915_gem_object.c
> index d9eca1b02aee..6d3516d5bff9 100644
> --- a/drivers/gpu/drm/i915/selftests/i915_gem_object.c
> +++ b/drivers/gpu/drm/i915/selftests/i915_gem_object.c
> @@ -499,6 +499,19 @@ static bool assert_mmap_offset(struct drm_i915_private *i915,
>  	return err == expected;
>  }
>  
> +static void disable_retire_worker(struct drm_i915_private *i915)
> +{
> +	mutex_lock(&i915->drm.struct_mutex);
> +	if (!i915->gt.active_requests++) {
> +		intel_runtime_pm_get(i915);
> +		i915_gem_unpark(i915);
> +		intel_runtime_pm_put(i915);
> +	}
> +	mutex_unlock(&i915->drm.struct_mutex);
> +	cancel_delayed_work_sync(&i915->gt.retire_work);
> +	cancel_delayed_work_sync(&i915->gt.idle_work);
> +}
> +
>  static int igt_mmap_offset_exhaustion(void *arg)
>  {
>  	struct drm_i915_private *i915 = arg;
> @@ -509,12 +522,7 @@ static int igt_mmap_offset_exhaustion(void *arg)
>  	int loop, err;
>  
>  	/* Disable background reaper */
> -	mutex_lock(&i915->drm.struct_mutex);
> -	if (!i915->gt.active_requests++)
> -		i915_gem_unpark(i915);
> -	mutex_unlock(&i915->drm.struct_mutex);
> -	cancel_delayed_work_sync(&i915->gt.retire_work);
> -	cancel_delayed_work_sync(&i915->gt.idle_work);
> +	disable_retire_worker(i915);
>  	GEM_BUG_ON(!i915->gt.awake);
>  
>  	/* Trim the device mmap space to only a page */
> -- 
> 2.18.0
Chris Wilson Aug. 9, 2018, 10:45 a.m. UTC | #2
Quoting Mika Kuoppala (2018-08-09 11:40:35)
> Chris Wilson <chris@chris-wilson.co.uk> writes:
> 
> > The call to i915_gem_unpark() checks that we hold a rpm wakeref before
> > taking a long term wakeref for i915->gt.awake. We should therefore make
> > sure we do hold the wakeref when directly calling unpark to disable
> > the retire worker.
> 
> We as a caller need to hold the rpm as i915_gem_unpark does 
> intel_runtime_pm_get_noresume() ?

Correct. noresume says that the caller must have down the synchronous
rpm_get for us.
-Chris
Mika Kuoppala Aug. 9, 2018, 10:49 a.m. UTC | #3
Chris Wilson <chris@chris-wilson.co.uk> writes:

> The call to i915_gem_unpark() checks that we hold a rpm wakeref before
> taking a long term wakeref for i915->gt.awake. We should therefore make
> sure we do hold the wakeref when directly calling unpark to disable
> the retire worker.
>
> Fixes: 932cac10c8fb ("drm/i915/selftests: Prevent background reaping of active objects")
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
> Cc: Matthew Auld <matthew.auld@intel.com>

Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_object.c b/drivers/gpu/drm/i915/selftests/i915_gem_object.c
index d9eca1b02aee..6d3516d5bff9 100644
--- a/drivers/gpu/drm/i915/selftests/i915_gem_object.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_object.c
@@ -499,6 +499,19 @@  static bool assert_mmap_offset(struct drm_i915_private *i915,
 	return err == expected;
 }
 
+static void disable_retire_worker(struct drm_i915_private *i915)
+{
+	mutex_lock(&i915->drm.struct_mutex);
+	if (!i915->gt.active_requests++) {
+		intel_runtime_pm_get(i915);
+		i915_gem_unpark(i915);
+		intel_runtime_pm_put(i915);
+	}
+	mutex_unlock(&i915->drm.struct_mutex);
+	cancel_delayed_work_sync(&i915->gt.retire_work);
+	cancel_delayed_work_sync(&i915->gt.idle_work);
+}
+
 static int igt_mmap_offset_exhaustion(void *arg)
 {
 	struct drm_i915_private *i915 = arg;
@@ -509,12 +522,7 @@  static int igt_mmap_offset_exhaustion(void *arg)
 	int loop, err;
 
 	/* Disable background reaper */
-	mutex_lock(&i915->drm.struct_mutex);
-	if (!i915->gt.active_requests++)
-		i915_gem_unpark(i915);
-	mutex_unlock(&i915->drm.struct_mutex);
-	cancel_delayed_work_sync(&i915->gt.retire_work);
-	cancel_delayed_work_sync(&i915->gt.idle_work);
+	disable_retire_worker(i915);
 	GEM_BUG_ON(!i915->gt.awake);
 
 	/* Trim the device mmap space to only a page */