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Subject: Re: [BUG] About "io_uring: add more uring info to fdinfo for debug"
To:     Jens Axboe <axboe@kernel.dk>, Eric Dumazet <edumazet@google.com>,
        Eric Dumazet <eric.dumazet@gmail.com>
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From:   Hao Xu <haoxu@linux.alibaba.com>
Message-ID: <b169a5b5-aa71-690a-f658-47dfe7a21785@linux.alibaba.com>
Date:   Sat, 30 Oct 2021 01:58:53 +0800
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在 2021/10/30 上午1:56, Jens Axboe 写道:
> On 10/29/21 11:54 AM, Hao Xu wrote:
>> Hi Jens,
>> I was thinking that print all the entries including the unused ones
>> would make the list very long(real product use hundreds or thousands
>> while there may be just several useful sqes). And that may be confused,
>> a example is: sq_array[0-999] = 0, we have only one sqe sqes[0] in use.
>> then we'll print sqe[0] 1000 times, though we can get to know the real
>> useful one by sq_head and tail info after calculation.
>> And if only print the useful ones, exposing the original counters will
>> make the loop condition a bit simpler than exposing the ring index(since
>> the original counters depend on natural overflow) though we cannot do
>> that now since realizing issues like what Eric reports.
> 
> We can revisit in the merge window, I wrote up the pull requests for
> this branch (among others) already. The most important part was fixing
> the looping to appropriately cap it.
> 
Gotcha