diff mbox series

[v5] dma-fence: Propagate errors to dma-fence-array container

Message ID 20190811162524.6131-1-chris@chris-wilson.co.uk (mailing list archive)
State New, archived
Headers show
Series [v5] dma-fence: Propagate errors to dma-fence-array container | expand

Commit Message

Chris Wilson Aug. 11, 2019, 4:25 p.m. UTC
When one of the array of fences is signaled, propagate its errors to the
parent fence-array (keeping the first error to be raised).

v2: Opencode cmpxchg_local to avoid compiler freakout.
v3: Be careful not to flag an error if we race against signal-on-any.
v4: Same applies to installing the signal cb.
v5: Use cmpxchg to only set the error once before using a nifty idea by
Christian to avoid changing the status after emitting the signal.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Gustavo Padovan <gustavo@padovan.org>
Cc: Christian König <christian.koenig@amd.com>
---
 drivers/dma-buf/dma-fence-array.c | 32 ++++++++++++++++++++++++++++++-
 1 file changed, 31 insertions(+), 1 deletion(-)

Comments

Christian König Aug. 11, 2019, 4:28 p.m. UTC | #1
Am 11.08.19 um 18:25 schrieb Chris Wilson:
> When one of the array of fences is signaled, propagate its errors to the
> parent fence-array (keeping the first error to be raised).
>
> v2: Opencode cmpxchg_local to avoid compiler freakout.
> v3: Be careful not to flag an error if we race against signal-on-any.
> v4: Same applies to installing the signal cb.
> v5: Use cmpxchg to only set the error once before using a nifty idea by
> Christian to avoid changing the status after emitting the signal.
>
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Sumit Semwal <sumit.semwal@linaro.org>
> Cc: Gustavo Padovan <gustavo@padovan.org>
> Cc: Christian König <christian.koenig@amd.com>

Reviewed-by: Christian König <christian.koenig@amd.com>

> ---
>   drivers/dma-buf/dma-fence-array.c | 32 ++++++++++++++++++++++++++++++-
>   1 file changed, 31 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/dma-buf/dma-fence-array.c b/drivers/dma-buf/dma-fence-array.c
> index 12c6f64c0bc2..d3fbd950be94 100644
> --- a/drivers/dma-buf/dma-fence-array.c
> +++ b/drivers/dma-buf/dma-fence-array.c
> @@ -13,6 +13,8 @@
>   #include <linux/slab.h>
>   #include <linux/dma-fence-array.h>
>   
> +#define PENDING_ERROR 1
> +
>   static const char *dma_fence_array_get_driver_name(struct dma_fence *fence)
>   {
>   	return "dma_fence_array";
> @@ -23,10 +25,29 @@ static const char *dma_fence_array_get_timeline_name(struct dma_fence *fence)
>   	return "unbound";
>   }
>   
> +static void dma_fence_array_set_pending_error(struct dma_fence_array *array,
> +					      int error)
> +{
> +	/*
> +	 * Propagate the first error reported by any of our fences, but only
> +	 * before we ourselves are signaled.
> +	 */
> +	if (error)
> +		cmpxchg(&array->base.error, PENDING_ERROR, error);
> +}
> +
> +static void dma_fence_array_clear_pending_error(struct dma_fence_array *array)
> +{
> +	/* Clear the error flag if not actually set. */
> +	cmpxchg(&array->base.error, PENDING_ERROR, 0);
> +}
> +
>   static void irq_dma_fence_array_work(struct irq_work *wrk)
>   {
>   	struct dma_fence_array *array = container_of(wrk, typeof(*array), work);
>   
> +	dma_fence_array_clear_pending_error(array);
> +
>   	dma_fence_signal(&array->base);
>   	dma_fence_put(&array->base);
>   }
> @@ -38,6 +59,8 @@ static void dma_fence_array_cb_func(struct dma_fence *f,
>   		container_of(cb, struct dma_fence_array_cb, cb);
>   	struct dma_fence_array *array = array_cb->array;
>   
> +	dma_fence_array_set_pending_error(array, f->error);
> +
>   	if (atomic_dec_and_test(&array->num_pending))
>   		irq_work_queue(&array->work);
>   	else
> @@ -63,9 +86,14 @@ static bool dma_fence_array_enable_signaling(struct dma_fence *fence)
>   		dma_fence_get(&array->base);
>   		if (dma_fence_add_callback(array->fences[i], &cb[i].cb,
>   					   dma_fence_array_cb_func)) {
> +			int error = array->fences[i]->error;
> +
> +			dma_fence_array_set_pending_error(array, error);
>   			dma_fence_put(&array->base);
> -			if (atomic_dec_and_test(&array->num_pending))
> +			if (atomic_dec_and_test(&array->num_pending)) {
> +				dma_fence_array_clear_pending_error(array);
>   				return false;
> +			}
>   		}
>   	}
>   
> @@ -142,6 +170,8 @@ struct dma_fence_array *dma_fence_array_create(int num_fences,
>   	atomic_set(&array->num_pending, signal_on_any ? 1 : num_fences);
>   	array->fences = fences;
>   
> +	array->base.error = PENDING_ERROR;
> +
>   	return array;
>   }
>   EXPORT_SYMBOL(dma_fence_array_create);
diff mbox series

Patch

diff --git a/drivers/dma-buf/dma-fence-array.c b/drivers/dma-buf/dma-fence-array.c
index 12c6f64c0bc2..d3fbd950be94 100644
--- a/drivers/dma-buf/dma-fence-array.c
+++ b/drivers/dma-buf/dma-fence-array.c
@@ -13,6 +13,8 @@ 
 #include <linux/slab.h>
 #include <linux/dma-fence-array.h>
 
+#define PENDING_ERROR 1
+
 static const char *dma_fence_array_get_driver_name(struct dma_fence *fence)
 {
 	return "dma_fence_array";
@@ -23,10 +25,29 @@  static const char *dma_fence_array_get_timeline_name(struct dma_fence *fence)
 	return "unbound";
 }
 
+static void dma_fence_array_set_pending_error(struct dma_fence_array *array,
+					      int error)
+{
+	/*
+	 * Propagate the first error reported by any of our fences, but only
+	 * before we ourselves are signaled.
+	 */
+	if (error)
+		cmpxchg(&array->base.error, PENDING_ERROR, error);
+}
+
+static void dma_fence_array_clear_pending_error(struct dma_fence_array *array)
+{
+	/* Clear the error flag if not actually set. */
+	cmpxchg(&array->base.error, PENDING_ERROR, 0);
+}
+
 static void irq_dma_fence_array_work(struct irq_work *wrk)
 {
 	struct dma_fence_array *array = container_of(wrk, typeof(*array), work);
 
+	dma_fence_array_clear_pending_error(array);
+
 	dma_fence_signal(&array->base);
 	dma_fence_put(&array->base);
 }
@@ -38,6 +59,8 @@  static void dma_fence_array_cb_func(struct dma_fence *f,
 		container_of(cb, struct dma_fence_array_cb, cb);
 	struct dma_fence_array *array = array_cb->array;
 
+	dma_fence_array_set_pending_error(array, f->error);
+
 	if (atomic_dec_and_test(&array->num_pending))
 		irq_work_queue(&array->work);
 	else
@@ -63,9 +86,14 @@  static bool dma_fence_array_enable_signaling(struct dma_fence *fence)
 		dma_fence_get(&array->base);
 		if (dma_fence_add_callback(array->fences[i], &cb[i].cb,
 					   dma_fence_array_cb_func)) {
+			int error = array->fences[i]->error;
+
+			dma_fence_array_set_pending_error(array, error);
 			dma_fence_put(&array->base);
-			if (atomic_dec_and_test(&array->num_pending))
+			if (atomic_dec_and_test(&array->num_pending)) {
+				dma_fence_array_clear_pending_error(array);
 				return false;
+			}
 		}
 	}
 
@@ -142,6 +170,8 @@  struct dma_fence_array *dma_fence_array_create(int num_fences,
 	atomic_set(&array->num_pending, signal_on_any ? 1 : num_fences);
 	array->fences = fences;
 
+	array->base.error = PENDING_ERROR;
+
 	return array;
 }
 EXPORT_SYMBOL(dma_fence_array_create);