Re: [dpdk-dev] [PATCH] examples/vhost: add error propagation in ioat ops

[Maxime Coquelin <maxime.coquelin@redhat.com>]

On 2/3/21 12:52 PM, Jiang, Cheng1 wrote:
> Hi,
> 
>> -----Original Message-----
>> From: Maxime Coquelin <maxime.coquelin@redhat.com>
>> Sent: Wednesday, February 3, 2021 5:49 PM
>> To: Jiang, Cheng1 <cheng1.jiang@intel.com>; Xia, Chenbo
>> <chenbo.xia@intel.com>
>> Cc: dev@dpdk.org; Hu, Jiayu <jiayu.hu@intel.com>; Yang, YvonneX
>> <yvonnex.yang@intel.com>; Wang, Yinan <yinan.wang@intel.com>
>> Subject: Re: [PATCH] examples/vhost: add error propagation in ioat ops
>>
>>
>>
>> On 1/31/21 1:36 PM, Cheng Jiang wrote:
>>> It makes more sense to add error propagation for rte_ioat_completed_ops.
>>>
>>> Signed-off-by: Cheng Jiang <Cheng1.jiang@intel.com>
>>> ---
>>>  examples/vhost/ioat.c | 14 ++++++++++----
>>>  1 file changed, 10 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/examples/vhost/ioat.c b/examples/vhost/ioat.c index
>>> dbad28d43..60b73be93 100644
>>> --- a/examples/vhost/ioat.c
>>> +++ b/examples/vhost/ioat.c
>>> @@ -22,7 +22,6 @@ struct packet_tracker {
>>>
>>>  struct packet_tracker cb_tracker[MAX_VHOST_DEVICE];
>>>
>>> -
>>>  int
>>>  open_ioat(const char *value)
>>>  {
>>> @@ -129,7 +128,7 @@ ioat_transfer_data_cb(int vid, uint16_t queue_id,
>>>  		struct rte_vhost_async_status *opaque_data, uint16_t count)
>> {
>>>  	uint32_t i_desc;
>>> -	int dev_id = dma_bind[vid].dmas[queue_id * 2 +
>> VIRTIO_RXQ].dev_id;
>>> +	uint16_t dev_id = dma_bind[vid].dmas[queue_id * 2 +
>>> +VIRTIO_RXQ].dev_id;
>>
>> This change from uint16_t to int does not seem related to the purpose of this
>> patch. Is it?
> 
> Yes, this change has nothing to do with adding the log, I just noticed uint16_t is more appropriate and changed here.
> I can only add the log if you think change the type of dev_id here is not ok.

Better to have two commits since these are two different changes.
At least please mention it in the commit message.

Thanks,
Maxime


> Thanks.
> Cheng
> 
>>
>>>  	struct rte_vhost_iov_iter *src = NULL;
>>>  	struct rte_vhost_iov_iter *dst = NULL;
>>>  	unsigned long i_seg;
>>> @@ -182,10 +181,17 @@ ioat_check_completed_copies_cb(int vid,
>> uint16_t queue_id,
>>>  		unsigned short mask = MAX_ENQUEUED_SIZE - 1;
>>>  		unsigned short i;
>>>
>>> -		int dev_id = dma_bind[vid].dmas[queue_id * 2
>>> +		uint16_t dev_id = dma_bind[vid].dmas[queue_id * 2
>>>  				+ VIRTIO_RXQ].dev_id;
>>>  		n_seg = rte_ioat_completed_ops(dev_id, 255, dump, dump);
>>> -		if (n_seg <= 0)
>>> +		if (n_seg < 0) {
>>> +			RTE_LOG(ERR,
>>> +				VHOST_DATA,
>>> +				"fail to poll completed buf on IOAT
>> device %u",
>>> +				dev_id);
>>> +			return 0;
>>> +		}
>>> +		if (n_seg == 0)
>>>  			return 0;
>>>
>>>  		cb_tracker[dev_id].ioat_space += n_seg;
>>>
>