[PATCH] drm/i915: Provide the perf pmu.module

[PATCH] drm/i915: Provide the perf pmu.module

[Chris Wilson]

Rather than manually implement our own module reference counting for perf
pmu events, finally realise that there is a module parameter to struct
pmu for this very purpose.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: stable@vger.kernel.org
---
 drivers/gpu/drm/i915/i915_pmu.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_pmu.c b/drivers/gpu/drm/i915/i915_pmu.c
index 28bc5f13ae52..056994224c6b 100644
--- a/drivers/gpu/drm/i915/i915_pmu.c
+++ b/drivers/gpu/drm/i915/i915_pmu.c
@@ -445,8 +445,6 @@ static void i915_pmu_event_destroy(struct perf_event *event)
 		container_of(event->pmu, typeof(*i915), pmu.base);
 
 	drm_WARN_ON(&i915->drm, event->parent);
-
-	module_put(THIS_MODULE);
 }
 
 static int
@@ -538,10 +536,8 @@ static int i915_pmu_event_init(struct perf_event *event)
 	if (ret)
 		return ret;
 
-	if (!event->parent) {
-		__module_get(THIS_MODULE);
+	if (!event->parent)
 		event->destroy = i915_pmu_event_destroy;
-	}
 
 	return 0;
 }
@@ -1130,6 +1126,7 @@ void i915_pmu_register(struct drm_i915_private *i915)
 	if (!pmu->base.attr_groups)
 		goto err_attr;
 
+	pmu->base.module	= THIS_MODULE;
 	pmu->base.task_ctx_nr	= perf_invalid_context;
 	pmu->base.event_init	= i915_pmu_event_init;
 	pmu->base.add		= i915_pmu_event_add;
-- 
2.20.1

Re: [Intel-gfx] [PATCH] drm/i915: Provide the perf pmu.module

[Tvrtko Ursulin]

On 16/07/2020 10:46, Chris Wilson wrote:
> Rather than manually implement our own module reference counting for perf
> pmu events, finally realise that there is a module parameter to struct
> pmu for this very purpose.
> 
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
> Cc: stable@vger.kernel.org
> ---
>   drivers/gpu/drm/i915/i915_pmu.c | 7 ++-----
>   1 file changed, 2 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_pmu.c b/drivers/gpu/drm/i915/i915_pmu.c
> index 28bc5f13ae52..056994224c6b 100644
> --- a/drivers/gpu/drm/i915/i915_pmu.c
> +++ b/drivers/gpu/drm/i915/i915_pmu.c
> @@ -445,8 +445,6 @@ static void i915_pmu_event_destroy(struct perf_event *event)
>   		container_of(event->pmu, typeof(*i915), pmu.base);
>   
>   	drm_WARN_ON(&i915->drm, event->parent);
> -
> -	module_put(THIS_MODULE);
>   }
>   
>   static int
> @@ -538,10 +536,8 @@ static int i915_pmu_event_init(struct perf_event *event)
>   	if (ret)
>   		return ret;
>   
> -	if (!event->parent) {
> -		__module_get(THIS_MODULE);
> +	if (!event->parent)
>   		event->destroy = i915_pmu_event_destroy;
> -	}
>   
>   	return 0;
>   }
> @@ -1130,6 +1126,7 @@ void i915_pmu_register(struct drm_i915_private *i915)
>   	if (!pmu->base.attr_groups)
>   		goto err_attr;
>   
> +	pmu->base.module	= THIS_MODULE;
>   	pmu->base.task_ctx_nr	= perf_invalid_context;
>   	pmu->base.event_init	= i915_pmu_event_init;
>   	pmu->base.add		= i915_pmu_event_add;
> 

Okay!

Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

Regards,

Tvrtko