[CRIU] Re: [PATCH 10/10] files: Use sys_kcmp to find file descriptor duplicates

[Pavel Emelyanov]

On 02/28/2012 05:10 PM, Cyrill Gorcunov wrote:
> On Tue, Feb 28, 2012 at 02:26:31PM +0400, Pavel Emelyanov wrote:
>> On 02/27/2012 07:21 PM, Cyrill Gorcunov wrote:
>>> On Mon, Feb 27, 2012 at 06:01:41PM +0400, Cyrill Gorcunov wrote:
>>>>
>>>> Yes, 0 will work as well but I would prefer to keep some predefined
>>>> value other than 0 which actually gives us a good hint in debugging
>>>> purpose.
>>>>
>>>
>>> Does this one look better?
>>
>> Almost perfect. See comments inline.
>>
> 
> The final one.

No, it's not :)

>         Cyrill
> +static struct fd_id_entry *alloc_fd_id_entry(u32 genid, pid_t pid, int fd)
> +{
> +       struct fd_id_entry *e;
> +
> +       e = xmalloc(sizeof(*e));
> +       if (!e)
> +               goto err;
> +
> +       e->u.key.subid  = fd_id_entries_subid++; /* just for the symmetry */
> +       e->u.key.genid  = genid;
> +       e->pid          = pid;
> +       e->fd           = fd;
> +
> +       rb_init_node(&e->node);
> +       rb_init_node(&e->subtree_node);
> +       rb_attach_node(&e->subtree_root, &e->subtree_node);
> +err:
> +       return e;
> +}
> +
> +static struct fd_id_entry *
> +lookup_alloc_subtree(struct fd_id_entry *e, u32 genid, pid_t pid, int fd)
> +{
> +
> +       sub = alloc_fd_id_entry(genid, pid, fd);
> +       if (!sub)
> +               goto err;
> +
> +       sub->u.key.subid = fd_id_entries_subid++;

It's already incremented in alloc_fd_id_entry :)

> +       rb_link_and_balance(&e->subtree_root, &sub->subtree_node, parent, new);

Plus, you can merge call to rb_link_and_balance into alloc_fd_id_entry (and rename
the latter to better reflect what it's doing.

> +err:
> +       return sub;