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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?6DeHxg/KwoFY61KH0x2hFyf14lsNKGfCSHOYXI6UCKTqOo4xgxyI+vQkZciy?= =?us-ascii?Q?WwQ4haz69LaNlqOFAqiStWx71tUjtqDAHZxt+y7oAsURkh1YkWS4VTJ6MqGv?= =?us-ascii?Q?jJOneeSLNMeanuRA8LVM7lOiwXc/+V3prQA+rlJKcr03U8+g+nn2zW3Lh5ZA?= =?us-ascii?Q?oO9Uu5CsRUEzZsA3H4qN7pz8RLEu7+diLOshJeACQ2winV+wxrUOBXZjbFKv?= =?us-ascii?Q?48B9rsJptoooc30eKPUC4z4Pxe0KhDmjzlBhglnAzPYr9yOLhozXdQhzusH0?= =?us-ascii?Q?njvcNL6tYAVvLR6TcNeUP9KrPQr2aY8rVzKl7l80L2JnddbVPFGBHktAJW0U?= =?us-ascii?Q?3K+1iT/P/D9HHh2D8aQVHxhrcUwmeSsdJ2/D6arv0ppgKW4nI6sLfj81zMIY?= =?us-ascii?Q?CWEwiDw8luz1EDHHtLS/dBA0fxABbkbbpt6T3wU09ykHqaZL1ZkF4LRqfGUc?= =?us-ascii?Q?/J82LdAbVrqcFw7gGClaygW5ZjJbCEDzsIqgepy/aeO47Okx9FtnKISXmzcR?= =?us-ascii?Q?0WmjFF9PuI4cNut0mn9DzdHVdM1rmAirC4XuNLc0LBusFmEHDYhaviO6Lhyp?= =?us-ascii?Q?AeYEvbUbtpR4jPLqdQrPA7RpQZVvoOXgTA76tGW1JjjN8RZjAtnhKKDAMhf1?= =?us-ascii?Q?MZpDOzudGnZvNfg3vnx5dkhwyL8r5PeqXRUaRMf7Y3JAWKtsXpF4kPPFUSlK?= =?us-ascii?Q?S0rTMmR6/p9B9040yVRU7iT1TP6gNjDredepQkRUbpGsOxQ83QqUeitAfJ41?= =?us-ascii?Q?EAkI+MVP5V65pSTbuZ3At/qJcENpCt7cCBrMk+TjGv7OFxTqV/RDYgA8GNu4?= =?us-ascii?Q?pefJ7FlUC0gUsh1WlcBZxcF5Ex7YaO2O64H0xDBDF8kIJ302x1dKJNGUZOjm?= =?us-ascii?Q?v7Or0+uvSnmBbBSh7m84shADf+hrEshfVAMuq35FsuFw0KUR/hWQcqLpFPZ0?= =?us-ascii?Q?yKgEf8HNQ0tK5FWb42sCg/hJd53KTFj7Hle+DGrbJkxvE66ifrOjNYgOm+Zk?= =?us-ascii?Q?WZAXa1Esm18+s/mH1AXK5u8xXASJBhuD/ORf6cpB+/go2T9udj193R9iJE9x?= =?us-ascii?Q?AiUBDU3/Vv9xdhnrI8bV6SNtUtix6GDKEZ/Palnxm/G5KDWmEXcN34wHRsID?= =?us-ascii?Q?ck6u2nID5nJpfczfUYuJhjsgbllh9r82Oe8PphL9rphDCmsauKbuGxwddMKD?= =?us-ascii?Q?c5ZqWfFgohbJVKxrsvcRVTChdkzFCgUkfc+wPgIOfjDMSdGoM0V0QhiAJ8lh?= =?us-ascii?Q?4jeHwrUXGhI84/chZ1hvWVW2P5GlC7G5B6roH+dVN/+BUgT5OgrK1+dE3gby?= =?us-ascii?Q?GReFFm8l+geXtvo7Id8UbTc7gVdfC7TDMTDUzyhIRx8LfW9N+EWUAkDMEIL3?= =?us-ascii?Q?FQ89uL6SVNvMGEAsc+HMFgTM2zUaGwbs/jnkqf47WSpcnirjTVl7XqaJSLPY?= =?us-ascii?Q?CniIftnhnUisC1ltd67Ubw3u+EzJIDOCuod4j2Fzm2AZSXCEcdhBdlfmu2dg?= =?us-ascii?Q?AcWWSnihdAHEzIOgb4tjAYnjrvsvsRsJainCL0GDW2elyvz20gBtg4d9Az6k?= =?us-ascii?Q?FFrJjS4JLBRkkCzDS3g=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 179bacb1-fcaf-4219-8fb0-08d9f61b1838 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB4192.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Feb 2022 15:50:48.3513 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: Cv6Ebg2rx7pO3JP3tM6pGv2dyl6E0HKXNZETxxgFIDqOFScaQueKQ8+OGfoAif1J X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA0PR12MB4446 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Tue, Feb 22, 2022 at 01:43:13AM +0000, Tian, Kevin wrote: > > > > + * Drivers should attempt to return estimates so that initial_bytes + > > > > + * dirty_bytes matches the amount of data an immediate transition to > > > > STOP_COPY > > > > + * will require to be streamed. > > > > > > I didn't understand this requirement. In an immediate transition to > > > STOP_COPY I expect the amount of data covers the entire device > > > state, i.e. initial_bytes. dirty_bytes are dynamic and iteratively returned > > > then why we need set some expectation on the sum of > > > initial+round1_dity+round2_dirty+... > > > > "will require to be streamed" means additional data from this point > > forward, not including anything already sent. > > > > It turns into the estimate of how long STOP_COPY will take. > > I still didn't get the 'match' part. Why should the amount of data which > has already been sent match the additional data to be sent in STOP_COPY? None of it is 'already been sent' the return values are always 'still to be sent' Jason