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X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 18 Sep 2025 19:43:34.9748 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 162e5e26-c93c-4e95-c0a1-08ddf6eba7df X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[216.228.118.232];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: CO1PEPF000075EF.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB7453 On Thu, Sep 18, 2025 at 11:49:43AM -0300, Jason Gunthorpe wrote: > On Thu, Sep 18, 2025 at 12:14:27AM -0700, Nicolin Chen wrote: > > > > Then, the "entry" sounds like a physical (v.s. "logical") table > > > > entry, e.g. a PTE that we usually say? > > > > > > I choose entry because it is related to PTE and in most cases you want > > > to work on the entries. The replication of entry to item is somewhat > > > hidden. > > > > > > From a HW perspective the TLB should be loading entries. > > > > In that case, "entry" should be a single "physical" element v.s. > > "logical", right? Because that's what HW/TLB physically loads. > > I would say HW/TLB loads logical entries when it supports > contiguity. It read a single table item and expand it to the larger > TLB "entry". Oh, I got wrong. Thanks for elaborating. "item" is a PTE and "entry" is a group of items/PTEs that set the CONTIG bit. TLB loads all those items/PTEs and combines them into a single TLB "entry". It seems difficult to define which one is physical or logical, as both "item" and "entry" physically exist in page table and in TLB respectively. Nicolin