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David Alan Gilbert" , Markus Armbruster , David Hildenbrand References: <20210319145249.425189-1-andrey.gruzdev@virtuozzo.com> <20210319145249.425189-2-andrey.gruzdev@virtuozzo.com> <20210322201716.GG16645@xz-x1> <2fb49f83-e31c-8c93-50b7-833026b06518@virtuozzo.com> <20210323145457.GC6486@xz-x1> <9311f31b-298f-d235-45bd-0ed9d66f9468@virtuozzo.com> <20210323183537.GH6486@xz-x1> From: Andrey Gruzdev Message-ID: Date: Wed, 24 Mar 2021 10:48:04 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.3.2 In-Reply-To: <20210323183537.GH6486@xz-x1> Content-Type: multipart/alternative; boundary="------------F709CD51FF95E6141BF765C7" Content-Language: en-US X-Originating-IP: [95.165.26.68] X-ClientProxiedBy: AM9P195CA0003.EURP195.PROD.OUTLOOK.COM (2603:10a6:20b:21f::8) To VI1PR08MB3375.eurprd08.prod.outlook.com (2603:10a6:803:87::29) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from [192.168.1.64] (95.165.26.68) by AM9P195CA0003.EURP195.PROD.OUTLOOK.COM (2603:10a6:20b:21f::8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3977.24 via Frontend Transport; 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envelope-from=andrey.gruzdev@virtuozzo.com; helo=EUR04-DB3-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, HTML_MESSAGE=0.001, 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" --------------F709CD51FF95E6141BF765C7 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit On 23.03.2021 21:35, Peter Xu wrote: > On Tue, Mar 23, 2021 at 08:21:43PM +0300, Andrey Gruzdev wrote: >>> For the long term I think we'd better have a helper: >>> >>> qemu_put_qio_channel_buffer(QEMUFile *file, QIOChannelBuffer *bioc) >>> >>> So as to hide this flush operation, which is tricky. We'll have two users so >>> far: >>> >>> bg_migration_completion >>> colo_do_checkpoint_transaction >>> >>> IMHO it'll be nicer if you'd do it in this patch altogether! >>> >>> Thanks, >>> >> Sorry, can't get the idea, what's wrong with the fix. > I'm fine with the fix, but I've got one patch attached just to show what I > meant, so without any testing for sure.. > > Looks more complicated than I thought, but again I think we should hide that > buffer flush into another helper to avoid overlooking it. Thanks, Peter, now I've got what you meant - not to overlook flush on buffer channel. But it seems that adding a reasonable comment is enough here. > > Thanks, > --------------F709CD51FF95E6141BF765C7 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: 7bit
On 23.03.2021 21:35, Peter Xu wrote:
On Tue, Mar 23, 2021 at 08:21:43PM +0300, Andrey Gruzdev wrote:

For the long term I think we'd better have a helper:

         qemu_put_qio_channel_buffer(QEMUFile *file, QIOChannelBuffer *bioc)

So as to hide this flush operation, which is tricky. We'll have two users so
far:

         bg_migration_completion
         colo_do_checkpoint_transaction

IMHO it'll be nicer if you'd do it in this patch altogether!

Thanks,


Sorry, can't get the idea, what's wrong with the fix.

I'm fine with the fix, but I've got one patch attached just to show what I
meant, so without any testing for sure..

Looks more complicated than I thought, but again I think we should hide that
buffer flush into another helper to avoid overlooking it.
Thanks, Peter, now I've got what you meant - not to overlook flush on buffer channel.
But it seems that adding a reasonable comment is enough here.


Thanks,


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