[CRIU] [PATCH v3 12/16] files: new "used" files introduced

[Stanislav Kinsburskiy]

14.12.2015 12:49, Pavel Emelyanov пишет:
> On 12/14/2015 02:24 PM, Stanislav Kinsburskiy wrote:
>>
>> 14.12.2015 12:21, Pavel Emelyanov пишет:
>>> On 12/10/2015 06:17 PM, Stanislav Kinsburskiy wrote:
>>>> This list contains all per-process used file fdinfo's, sorted by fd number.
>>>> Will be used to safely create new artificial file descriptors and also allow
>>>> to recreate temporary descriptors with original number, if possible, like
>>>> AutoFS tries to preserve original pipe write end descriptor, when it was
>>>> closed.
>>> AFAIU you only need this to find the first unused descriptor number. Why
>>> not just have max_fd number in the rst_info and update one in every place
>>> a new fd is added?
>> This can be done like this, yes.
>> One of the intentions was to try to keep autofs restored options as
>> close to original as possible.
>> The actual idea was to try to reopen write end of the pipe with the same
>> fd, as it was originally.
>> To be able to do so, loop over all the descriptor is required to make
>> sure, that fd is not busy.
> But where is this code? The only usage for used list is to find the first
> unused one (patch #13) and, btw, the only benefit of the list as compared to
> the plan max_used_fd value -- the ability to get a 'hole' between used fds --
> is not taken in this patch.
>

It's patch #13 with find_unused_fd() helper and patch #15, which uses 
this helper.