[CRIU] [PATCH 2/3] files: split collect_fd on allocate_fd and handle_fd

[Andrew Vagin]

On Wed, Aug 10, 2016 at 03:34:51PM +0300, Pavel Emelyanov wrote:
> 
> > @@ -723,14 +732,23 @@ static int collect_fd(int pid, FdinfoEntry *e, struct rst_info *rst_info)
> >  	else
> >  		collect_gen_fd(new_le, rst_info);
> >  
> > -	collect_used_fd(new_le, rst_info);
> > -
> >  	list_add_tail(&new_le->desc_list, &le->desc_list);
> >  	new_le->desc = fdesc;
> >  
> >  	return 0;
> >  }
> >  
> > +static int collect_fd(int pid, FdinfoEntry *e, struct rst_info *rst_info)
> > +{
> > +	struct fdinfo_list_entry *le;
> > +
> > +	le = allocate_fd(pid, e, rst_info);
> > +	if (le == NULL)
> > +		return -1;
> > +
> > +	return handle_fd(le, rst_info);
> > +}
> > +
> 
> Presence of this function even after patching makes me think, that after collect
> stage you're still not 100% sure which fds are used which are not.

All used fds is saved in an fdinfo image. In a few cases we need to
allocate an extran fdinfo and it looks like this:

        fd = find_unused_fd(&rsti(task)->used, new_fd);

        e = dup_fdinfo(ple->fe, fd, flags);

        return collect_fd(task->pid.virt, e, rsti(task));


> 
> -- Pavel