Re: [PATCH v2 3/4] examples/dma: support enqueue drop statistic

[fengchengwen <fengchengwen@huawei.com>]

On 2022/4/19 16:45, Bruce Richardson wrote:
> On Sat, Apr 16, 2022 at 02:19:24PM +0800, fengchengwen wrote:
>> DMA is a memcopy engine, and from that perspective, I think it's appropriate
>> to use copy_failures when dma_enqueue fails.
>>
>> The newly added enqueue_failures is mainly used for rte_ring_enqueue_burst
>> failures.
>>
>> Since the app doesn't have a command line, I think adding this field can
>> immediately identify where it failed.
>>
> 
> So one stat is for the HW path and the other is for the SW one? If that is
> the case, only one stat should probably be printed out by the app depending
> on the mode is it in.

For HW path, both copy_failures and enqueue_failures
For SW path, only the enqueue_failure, PS: the value of copy_failures is fixed to be 0

> 
>> On 2022/4/13 23:01, Bruce Richardson wrote:
>>> On Mon, Apr 11, 2022 at 08:14:58PM +0800, Chengwen Feng wrote:
>>>> The copy drop statistic counted in two scenarios: DMA copy failures and
>>>> enqueue failures. so it is difficult to locate the problem.
>>>>
>>>
>>> Is the app actually tracking copy failures? From a quick glance at the code
>>> it looks to me like the only "copy_failures" are the enqueue failures, in
>>> which case the stat should just be renamed.
>>>
>>>> This patch adds enqueue drop statistic to fix the it.
>>>>
>>>> Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
>>>> ---
>>>>  examples/dma/dmafwd.c | 14 +++++++++-----
>>>>  1 file changed, 9 insertions(+), 5 deletions(-)
>>>>
>>>
>>> .
>>>
>>
> 
> .
>