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X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Nov 2025 18:48:51.6593 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: eb284dce-c747-467e-2a70-08de1bd2cc58 X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[216.228.117.160];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: CH1PEPF0000A349.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB5638 On Tue, Nov 04, 2025 at 10:25:39AM -0800, Jacob Pan wrote: > > ----------------------------------------------------------------- > > > > And the commit message should point out: > > > > The existing arm_smmu_cmdq_poll_until_not_full() doesn't fit > > efficiently nor ideally to the only caller > > arm_smmu_cmdq_issue_cmdlist(): > > - It uses a new timer at every single call, which fails to limit to > > the preset ARM_SMMU_POLL_TIMEOUT_US per issue. > Not following what you mean. > The original code below does honor the timeout of > ARM_SMMU_POLL_TIMEOUT_US It sets the timeout per arm_smmu_cmdq_poll_until_not_full(), not the entire wait-for-space routine. And that's why you moved the queue_poll_init() to the caller, right? Nicolin