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dkim=none (message not signed) header.d=none;openvz.org; dmarc=none action=none header.from=virtuozzo.com; Received: from AM7PR08MB5494.eurprd08.prod.outlook.com (2603:10a6:20b:dc::15) by AS8PR08MB6870.eurprd08.prod.outlook.com (2603:10a6:20b:39a::21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4195.24; Wed, 9 Jun 2021 15:49:47 +0000 Received: from AM7PR08MB5494.eurprd08.prod.outlook.com ([fe80::f928:f4f2:77c0:74b4]) by AM7PR08MB5494.eurprd08.prod.outlook.com ([fe80::f928:f4f2:77c0:74b4%9]) with mapi id 15.20.4195.030; Wed, 9 Jun 2021 15:49:47 +0000 Subject: Re: [PATCH v3 14/33] nbd: move connection code from block/nbd to nbd/client-connection From: Vladimir Sementsov-Ogievskiy To: Roman Kagan , qemu-block@nongnu.org, qemu-devel@nongnu.org, eblake@redhat.com, mreitz@redhat.com, kwolf@redhat.com, den@openvz.org References: <20210416080911.83197-1-vsementsov@virtuozzo.com> <20210416080911.83197-15-vsementsov@virtuozzo.com> <84aaa2dc-7a86-c540-fd82-6729d568cd50@virtuozzo.com> Message-ID: <567676c6-9e1e-b7d8-2c57-300cf454b2fc@virtuozzo.com> Date: Wed, 9 Jun 2021 18:49:45 +0300 User-Agent: Mozilla/5.0 (X11; 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envelope-from=vsementsov@virtuozzo.com; helo=EUR04-HE1-obe.outbound.protection.outlook.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, MSGID_FROM_MTA_HEADER=0.001, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" 28.04.2021 11:14, Vladimir Sementsov-Ogievskiy wrote: >>> +struct NBDClientConnection { >>> +    /* Initialization constants */ >>> +    SocketAddress *saddr; /* address to connect to */ >>> + >>> +    /* >>> +     * Result of last attempt. Valid in FAIL and SUCCESS states. >>> +     * If you want to steal error, don't forget to set pointer to NULL. >>> +     */ >>> +    QIOChannelSocket *sioc; >>> +    Error *err; >> >> These two are also manipulated under the mutex.  Consider also updating >> the comment: both these pointers are to be "stolen" by the caller, with >> the former being valid when the connection succeeds and the latter >> otherwise. >> > > Hmm. I should move mutex and "All further" comment above these two fields. > > Ok, I'll think on updating the comment (probably as an additional patch, to keep this as a simple movement). I don't like to document that they are stolen by caller(). For me it sounds like caller is user of the interface. And caller of nbd_co_establish_connection() doesn't stole anything: the structure is private now.. Finally, I decided to improve the comment as part of "[PATCH v3 08/33] block/nbd: drop thr->state" commit, as "FAIL and SUCCESS states" string becomes outdated when we drop these states. -- Best regards, Vladimir