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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?2TtN0hMa4XHRbhbV64snsgWKln1Pu/6hKv88R91mk0z4TkPu6MPVy1MgZRCW?= =?us-ascii?Q?Vs8ZPAp2vcxUcNanUZq7XWhV9X0UOYxpmwviJ7l7yHQdyD2G5ms0f8eUdAmo?= =?us-ascii?Q?QTIRSR5/7+zt0ev+/NANjMjU0CoFiJMU36b5v+bxwFzs5hQP5qDc8Db6bUa/?= =?us-ascii?Q?tNKNQ9EnfdTJQdcoLLHXoT3+HOWcx3ub2fI1RzenRVQbgeK/gMlTAN+dKMij?= =?us-ascii?Q?68Eckcl24B2himidbjHH5KFCfrwpmrvBx4+vMfBhgaxu3CPEjAY1punqdFAx?= =?us-ascii?Q?CxQpnKIrdpFNL2R4Pa3Peh8Jej4qDFBlXohZbtjwalS0EpoNNXNWP5whkETb?= =?us-ascii?Q?8R9KR6Rtkd43RfG5jwNqMuL6re0C4xCiancQRxO1O0l1FgqSH0ZnxPIMLyvu?= =?us-ascii?Q?XT8BXlsaJz5MhrPMZQbR92VVOzC0i+WAO4xD0tjWSDcrrkQHu5AB0z12zS3W?= =?us-ascii?Q?HB0dQYvRCxGb8QnQqL9n6yy+dR+M/GNXU+7UHWSDm5RFc7tNFayvcI0Smnbf?= =?us-ascii?Q?wLReuTfQP1JcIrlmkVNv0qKF0H2waJCM6FAHmhDmpSCu3+FCs18PynhgS/Ee?= =?us-ascii?Q?6G3CuSaNbtEXU5nuXFM2PPJrmcLBfnuGHTCmBZ1gMN2EwcZny/VMFC1kb0ze?= =?us-ascii?Q?wuSGzCM2a6r8GvOwVncKJjfbysc+ocK62M0ZG18wuOjQJ2Y6At5MojgnZkos?= =?us-ascii?Q?ymjRbknJLnNQUwVeVl2L2fobeYTv0rTLXc/Hv19dZnKlmTjHbCLh7IFkWSTr?= =?us-ascii?Q?AKgc+d1mRo5sQg375tTDBo1KN5fKKIOQFrLNjHm2ivAE9qq4uWz9LxjICvXq?= =?us-ascii?Q?S7DOFZQm7x9xaaWmNFCf/3o/uyDDaoD5E3QCyXOHLSgyU6/8NRmx0YQ/u1aQ?= =?us-ascii?Q?INGsMAdD8DAMkkQjsBfVAGoLlxhWa2jm3FZgpKL8mSIxiUWgnmQnV2/4z1bi?= =?us-ascii?Q?7vEg8dHkOG+28Ksl5jdARPuD+3g/FybLbeJVkHCW9AMgiX1KBSuMFIkJNsLF?= =?us-ascii?Q?BdELv3pw9BcoQ/af+RvSxlo1GYsmH/vjxo76icOBwJqXP+/arKWDqUqckh/y?= =?us-ascii?Q?/L9DSlqIGynLbI1eLr1YMW036ZagSH7wKum9GginsizxX3zXrJNuWu0LSYrm?= =?us-ascii?Q?Uj7HYJ3oLceVeg8HlXHornFMfcfMxQsSMmoHRo3dbhl/9dGaCz7ajcOjCtbc?= =?us-ascii?Q?d7qztDs6+Tex+EYvuLd/Xq8kxcdj4gwsRbipMMB+4nO7IilZj7YbpCq+Bwgl?= =?us-ascii?Q?vuWwLswGRCSQTSvv2wFaxUUz0L3vmzQeOQEy5lT9iqsy8aexF4R48+XJu+a4?= =?us-ascii?Q?XzT/pskAW+ceH8MxHF02n0x+6pwtbjqFKu0OLuMz6XFeu7WXaTRlBNvcZSlg?= =?us-ascii?Q?+R1MWYjTXYuXhB1i9fFL0n94Mo3HD7H9MnAgxbxQIAgUHlUyL2u0FGs3AQWX?= =?us-ascii?Q?dCs8jclf5ILHz9F8bUKND5wSwkGDjW4eZsEEutWkq90cV517NWptFXwsgZX1?= =?us-ascii?Q?XtM1T4YUDYPAZVLkb4wkt0oep1/R2OggrrGesPefLeLXpGiA3ZKKL/6An8it?= =?us-ascii?Q?i9m/38/MBG8lTXMHlzwg5jMG6Bt7VeIEuEiyOQCKTfJnIGG3cAMP8D7ymnzV?= =?us-ascii?Q?MVDKW4DvVrTpUPI3hE257IWVsG0u3/obv4b+GCLY/CjShoyYlC/T/f8DcwJ/?= =?us-ascii?Q?WWRmFdXxVO1OoGLYqmeInSmfqymfIAuM37toVuo1oWi2pB55UFEGMGNY7070?= =?us-ascii?Q?WBD+bx6T+A=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 868cb5e6-1264-428d-4081-08da19889b01 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB4192.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 08 Apr 2022 17:52:53.5330 (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: dUcNqaMRGBJlE+iSbxmXZWhOitAQiCaSjzz1hNKPHSUjRt5V5KpnW+j7K+9sv/6T X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR12MB3753 Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Mon, Apr 04, 2022 at 04:50:53PM -0500, Bob Pearson wrote: > In the tasklets (completer, responder, and requester) check the > return value from rxe_get() to detect failures to get a reference. > This only occurs if the qp has had its reference count drop to > zero which indicates that it no longer should be used. This is > in preparation to an upcoming change that will move the qp cleanup > code to rxe_qp_cleanup(). These need some comments explaining how this is safe.. It looks to me like it works because the 0 ref keeps the memory alive while a work queue triggers rxe_cleanup_task() (though who fences the responder task?) At least after the next patch, I'm a little unclear how this works at this moment.. Jason