[CRIU] Re: [PATCH 8/8] sockets: Restore in-flight unix stream sockets

[Pavel Emelyanov]

On 01/27/2012 07:56 PM, Cyrill Gorcunov wrote:
> On Fri, Jan 27, 2012 at 07:41:58PM +0400, Pavel Emelyanov wrote:
>>> +	u8	status;
>>
>> u8 flags;
>>
>> #define USK_INFLIGHT	0x1
>>
>> etc...
>>
> 
> ok
> 
>>>  
>>>  static struct socket_desc *sockets[SK_HASH_SIZE];
>>> -__gen_static_lookup_func(struct socket_desc, lookup_socket, sockets, ino, int, ino);
>>> +__gen_static_lookup_func(struct socket_desc, lookup_socket, sockets, ino, unsigned int, ino);
>>
>> Why do you change int into unsigned int? "While I'm at it" changes should go in separate patches.
>>
> 
> ok
> 
>>> +
>>> +static struct unix_sk_memo *unix_memos[SK_HASH_SIZE];
>>> +__gen_static_lookup_func(struct unix_sk_memo, lookup_unix_memo, unix_memos, ino, unsigned int, ino);
>>
>> This hashtable should be called unix_listeners.
>> Why can't we put the existing socket desc here? Why yet another unix_sk_memo?
>>
> 
> Because it's different types. This hash serves 2 purposes -- at checkpoint type
> it collects listeners _and_ icons, while at restore type it collects listeners
> only. So plain socket_desc is not enought here. Moreover when you read unix
> entries from image you save it in local variable and then create connect-job
> if needed but I have to carry every-single listening socket read from disk
> and can free it after connect-job complete.
> 
> Thus I thought having one separate structure and hash over it -- would be
> easier than anything else.

Сделай отдельный hashtable для listen сокетов. Только не для всех подряд listen,
а для тех, которые оригинально, из image, listen.

Потом логика будет простой.

dump:
if (sk->peer == 0 && sk->state == TCP_ESTABLISHED) {
	/* inflight */
	l = lookup_listener_with_icons(sk->id); /* проходим по хешу и ищем */
	if (l == NULL)
		return -1; /* dangling inflight? */
	sk->peer = l->id;
	sk->flags = INFLIGHT;
}

restore:
if (sk->state == TCP_LISTEN)
	add_to_hash(sk, usk_listeners);
else if (sk->flags & INFLIGHT)
	l = lookup_listener_by_id(sk->peer);
	run_connect_job(sk, l);


>>>  static int sk_collect_one(int ino, int family, struct socket_desc *d)
>>>  {
>>
> 
> 	Cyrill
> .
>