[PATCH] dma-buf: use irq work for dma_fence_array_enable_signaling

[Chunming Zhou]

Tested-And-Reviewed-by: Chunming Zhou <david1.zhou at amd.com>


在 2018/11/9 20:20, Christian König 写道:
> Also use the irq work for dma_fence_array_enable_signaling to make sure
> that the spinlock for the dma-fence-array is always unrelated to all
> other spinlocks.
>
> This fixes a lockdep warning if a dma-fence-array is embedded into
> another dma-fence-array.
>
> Signed-off-by: Christian König <christian.koenig at amd.com>
> ---
>   drivers/dma-buf/dma-fence-array.c | 20 +++++++++++++-------
>   1 file changed, 13 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/dma-buf/dma-fence-array.c b/drivers/dma-buf/dma-fence-array.c
> index a8c254497251..3adf6b04f5fd 100644
> --- a/drivers/dma-buf/dma-fence-array.c
> +++ b/drivers/dma-buf/dma-fence-array.c
> @@ -31,7 +31,7 @@ static const char *dma_fence_array_get_timeline_name(struct dma_fence *fence)
>   	return "unbound";
>   }
>   
> -static void irq_dma_fence_array_work(struct irq_work *wrk)
> +static void dma_fence_array_cb_work(struct irq_work *wrk)
>   {
>   	struct dma_fence_array *array = container_of(wrk, typeof(*array), work);
>   
> @@ -52,12 +52,13 @@ static void dma_fence_array_cb_func(struct dma_fence *f,
>   		dma_fence_put(&array->base);
>   }
>   
> -static bool dma_fence_array_enable_signaling(struct dma_fence *fence)
> +static void dma_fence_array_enable_signaling_work(struct irq_work *wrk)
>   {
> -	struct dma_fence_array *array = to_dma_fence_array(fence);
> +	struct dma_fence_array *array = container_of(wrk, typeof(*array), work);
>   	struct dma_fence_array_cb *cb = (void *)(&array[1]);
>   	unsigned i;
>   
> +	init_irq_work(&array->work, dma_fence_array_cb_work);
>   	for (i = 0; i < array->num_fences; ++i) {
>   		cb[i].array = array;
>   		/*
> @@ -71,12 +72,19 @@ 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)) {
> -			dma_fence_put(&array->base);
>   			if (atomic_dec_and_test(&array->num_pending))
> -				return false;
> +				dma_fence_signal(&array->base);
> +			dma_fence_put(&array->base);
>   		}
>   	}
> +}
>   
> +static bool dma_fence_array_enable_signaling(struct dma_fence *fence)
> +{
> +	struct dma_fence_array *array = to_dma_fence_array(fence);
> +
> +	init_irq_work(&array->work, dma_fence_array_enable_signaling_work);
> +	irq_work_queue(&array->work);
>   	return true;
>   }
>   
> @@ -144,8 +152,6 @@ struct dma_fence_array *dma_fence_array_create(int num_fences,
>   	spin_lock_init(&array->lock);
>   	dma_fence_init(&array->base, &dma_fence_array_ops, &array->lock,
>   		       context, seqno);
> -	init_irq_work(&array->work, irq_dma_fence_array_work);
> -
>   	array->num_fences = num_fences;
>   	atomic_set(&array->num_pending, signal_on_any ? 1 : num_fences);
>   	array->fences = fences;