[dpdk-dev] [PATCH v10 12/16] dma/idxd: add vchan status function

[fengchengwen]

On 2021/10/19 22:10, Kevin Laatz wrote:
> When testing dmadev drivers, it is useful to have the HW device in a known
> state. This patch adds the implementation of the function which will wait
> for the device to be idle (all jobs completed) before proceeding.
> 
> Signed-off-by: Kevin Laatz <kevin.laatz at intel.com>
> Reviewed-by: Conor Walsh <conor.walsh at intel.com>
> ---
>  drivers/dma/idxd/idxd_bus.c      |  1 +
>  drivers/dma/idxd/idxd_common.c   | 17 +++++++++++++++++
>  drivers/dma/idxd/idxd_internal.h |  2 ++
>  drivers/dma/idxd/idxd_pci.c      |  1 +
>  4 files changed, 21 insertions(+)
> 
> diff --git a/drivers/dma/idxd/idxd_bus.c b/drivers/dma/idxd/idxd_bus.c
> index b52ea02854..e6caa048a9 100644
> --- a/drivers/dma/idxd/idxd_bus.c
> +++ b/drivers/dma/idxd/idxd_bus.c
> @@ -101,6 +101,7 @@ static const struct rte_dma_dev_ops idxd_bus_ops = {
>  		.dev_info_get = idxd_info_get,
>  		.stats_get = idxd_stats_get,
>  		.stats_reset = idxd_stats_reset,
> +		.vchan_status = idxd_vchan_status,
>  };
>  
>  static void *
> diff --git a/drivers/dma/idxd/idxd_common.c b/drivers/dma/idxd/idxd_common.c
> index fd81418b7c..3c8cff15c0 100644
> --- a/drivers/dma/idxd/idxd_common.c
> +++ b/drivers/dma/idxd/idxd_common.c
> @@ -163,6 +163,23 @@ get_comp_status(struct idxd_completion *c)
>  	}
>  }
>  
> +int
> +idxd_vchan_status(const struct rte_dma_dev *dev, uint16_t vchan __rte_unused,
> +		enum rte_dma_vchan_status *status)
> +{
> +	struct idxd_dmadev *idxd = dev->fp_obj->dev_private;
> +	uint16_t last_batch_write = idxd->batch_idx_write == 0 ? idxd->max_batches :
> +			idxd->batch_idx_write - 1;
> +	uint8_t bstatus = (idxd->batch_comp_ring[last_batch_write].status != 0);
> +
> +	/* An IDXD device will always be either active or idle.
> +	 * RTE_DMA_VCHAN_HALTED_ERROR is therefore not supported by IDXD.
> +	 */
> +	*status = bstatus ? RTE_DMA_VCHAN_IDLE : RTE_DMA_VCHAN_ACTIVE;

why not use stats.submitted and completed ? or I miss some thing about this API?

does this api must called after rte_dma_submit() ? If not the following seq will function fail:
  enqueue multiple copy request
  submit to hardware
  enqueue multiple copy request
  invoke rte_dma_vchan_status to query status  --because the copy requests not submit, the last comp will be non-zero, so it will return IDLE.

> +
> +	return 0;
> +}
> +
>  static __rte_always_inline int
>  batch_ok(struct idxd_dmadev *idxd, uint16_t max_ops, enum rte_dma_status_code *status)
>  {
> diff --git a/drivers/dma/idxd/idxd_internal.h b/drivers/dma/idxd/idxd_internal.h
> index a85a1fb79e..50acb82d3d 100644
> --- a/drivers/dma/idxd/idxd_internal.h
> +++ b/drivers/dma/idxd/idxd_internal.h
> @@ -102,5 +102,7 @@ uint16_t idxd_completed_status(void *dev_private, uint16_t qid __rte_unused,
>  int idxd_stats_get(const struct rte_dma_dev *dev, uint16_t vchan,
>  		struct rte_dma_stats *stats, uint32_t stats_sz);
>  int idxd_stats_reset(struct rte_dma_dev *dev, uint16_t vchan);
> +int idxd_vchan_status(const struct rte_dma_dev *dev, uint16_t vchan,
> +		enum rte_dma_vchan_status *status);
>  
>  #endif /* _IDXD_INTERNAL_H_ */
> diff --git a/drivers/dma/idxd/idxd_pci.c b/drivers/dma/idxd/idxd_pci.c
> index 9d7f0531d5..23c10c0fb0 100644
> --- a/drivers/dma/idxd/idxd_pci.c
> +++ b/drivers/dma/idxd/idxd_pci.c
> @@ -140,6 +140,7 @@ static const struct rte_dma_dev_ops idxd_pci_ops = {
>  	.stats_reset = idxd_stats_reset,
>  	.dev_start = idxd_pci_dev_start,
>  	.dev_stop = idxd_pci_dev_stop,
> +	.vchan_status = idxd_vchan_status,
>  };
>  
>  /* each portal uses 4 x 4k pages */
>