Re: [PATCH] io_uring: add more uring info to fdinfo for debug

Hao Xu
2021-09-16T06:29:49Z

在 2021/9/15 下午11:32, Jens Axboe 写道:
> On 9/15/21 9:31 AM, Pavel Begunkov wrote:
>> On 9/15/21 4:26 PM, Jens Axboe wrote:
>>> On 9/13/21 7:08 AM, Hao Xu wrote:
>>>> Developers may need some uring info to help themselves debug and address
>>>> issues, these info includes sqring/cqring head/tail and the detail
>>>> sqe/cqe info, which is very useful when it stucks.
>>>
>>> I think this is a good addition, more info to help you debug a stuck case
>>> is always good. I'll queue this up for 5.16.
>>
>> Are there limits how much we can print? I remember people were couldn't
>> even show a list of CPUs (was it proc?). The overflow list may be huge.
>
> It's using seq_file, so I _think_ we should be fine here. Not sure when/if
> it truncates.
>
It seems the default buf size of seq_file is PAGE_SIZE.