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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?wjMjbioCZ6f/AS7gj9ieEtMarFF+RYLNGGDeM7vxFovctf7O79zBhkNQ+y15?= =?us-ascii?Q?n+nJ8zqt4yFcnjaPYdkmvT+U8pJOB/aIt67tetC+VOKZNM+AchJ3vhKeSvMw?= =?us-ascii?Q?5sLiaw2SL5QhNY46Zm74KPNnoCNrg+85E+2Ksh0yf6CM6VOF1faTE15lOFP9?= =?us-ascii?Q?xSmF0tpScUySE66blXVwZrJesgAupIjvktmXtJY70/5fVxm3ofjzLHZ0svsy?= =?us-ascii?Q?zSDJuxVrCHMPl4FEoqYjLuWKREUwYiYrf9gFS+KsQ+2Jqr8/QSIGOAPh3NLn?= =?us-ascii?Q?tkZnBaYfwptY+CUmmEdIieqdH0u+qI1TOOFRQ+nZNedwMhIvQMhgPFaeUiJA?= =?us-ascii?Q?UuEEeTT4JGbZeyRUlRQWBv8N4kNrMpJe2l7Mc9YpOFPi9k1rS7KYY9XD+1an?= =?us-ascii?Q?zml8lzeRNYFcjLB6ua6f0oM29b29cd2DsaRIRCC2HIpOrIaifp97F9geilIQ?= =?us-ascii?Q?fuhsui2GhgorrbwSD8yYKBtAVditJS/tk9OOVNtfK1Um8uCHoH2SqM4J6jHz?= =?us-ascii?Q?6rRc+0wY2/vt3cqLxSbao4vtAGsc+JuFyXXlkYzYtJdfaR5D4sjXLymnjAhD?= =?us-ascii?Q?i+mwutYYFNwdvCOUXk8PhehwQSK3PZFkHT/KuJbLjNJP9frZJ6MM+YjsL1fc?= =?us-ascii?Q?bE4NvHdi4gBiGhef8ipyCpCC9nvhGlVNpggOCJqR12NCt4pNc1mOAKXcFJ4O?= =?us-ascii?Q?wCdFKAUWavcFegj+75wngtcfA08EPTSIYz9ztAvLGG9BbNCobzn+lOgtJgxn?= =?us-ascii?Q?satin+C4IYMa+WTjYNiUjf3K2m2DfcIdA+rVYygOUwCDpxjioAnzuKSl9lsC?= =?us-ascii?Q?AJDWEhXs9bPrct4eSBHckXrwePAsOrsq57b7D/5y07+/PhgDUqaBoNNhhngM?= =?us-ascii?Q?rNR7QSli1JwsLghGc+Kgiu/2LeaLYqj7ChB1v1tlFbTnGXoKXd1nCX7CHLu4?= =?us-ascii?Q?Gni1tvRd5l3K19DPIpeioLtqZd4GjhP8QLkJzxOt1BPGDvo3OPR4T289OjCS?= =?us-ascii?Q?Vql7ziO8BC3D/8MvU0Cso7fkIi/JJ0ETUKBw6HNS1/jenfVJE2lDQ56zJ09T?= =?us-ascii?Q?CfeBp/wkwELjHpB7Af1Sc0X0Tvjw4/g7HtY4DlZko2ZLRslkE2axvnwhXiWa?= =?us-ascii?Q?NLx+jHY428ptlfhfxvfqq1oY2TuMEmNXxh94cHjdBE6tynrsYgxjMKOPJNOB?= =?us-ascii?Q?eVRHOJeBSWiBzpUvDHjvvlVA80YbUxBC6IdHe7w2olFjJpG1HS71A3uR37e5?= =?us-ascii?Q?8kQMBMCoKziTzNd9XK4a3xrT/SKkGbxPSTH8jssM3W/6Y6qgK6MYNHPmcEeG?= =?us-ascii?Q?Tp9Y0tHoaBZo5nmMyHTvYO5rOBLT5LNwPeafTcl+Ca8sffsBW6HbVLiR7Df7?= =?us-ascii?Q?26NOOu2StnvMTygnkPiuK6vihP4ggFPflB4ZXgHRmtRsw1Q43bGFyQPl0plo?= =?us-ascii?Q?uPQVYqZ5TUAKDISC9S7JDNAWD2ZOr4baq4UtyDzTNBra8cbPwJgJbYeBoGt3?= =?us-ascii?Q?sFQ27L+Pvu1jY4hrxnd4iLem/Qp14rEFmjKO6rwRvkHl/n1FIx0F5+Xq0Mmy?= =?us-ascii?Q?DF1ZB4XriErLbA6wQPQ=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 7e9a85e1-1fb4-4d47-c7f0-08dab90a7338 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 28 Oct 2022 17:32:56.1665 (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: 7ApgdSCt+pFanZbvKlawj83RfF5iRZqnTTVDUjQjYWezVMUsMYCyLibkTlsUe6zP X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ0PR12MB5408 Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Thu, Oct 06, 2022 at 12:04:55PM -0500, Bob Pearson wrote: > Currently the rxe driver uses a spin_lock_irqsave call to protect > the producer end of a completion queue from multiple QPs which may > be sharing the cq. Since all accesses to the cq are from tasklets > this is overkill and a simple spin_lock will be sufficient. A tasklet is a softirq, which means it needs to use the BH suffix for all acquires that are in a process context if it the spinlock is obtained from a tasklet There is a nice table in Documentation/kernel-hacking/locking.rst that explains this. Jason