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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?IAySl2/9+iJNtVeRnQI0khuS7jpV8Nctew82mEn77I+FZxlznyrhY3FW9nLj?= =?us-ascii?Q?VsZBEM2/aHZvNJIIb5TyZMzVBjr/bsyJAeQR556Ie6OAjKrpx+FYXeQ4eQrB?= =?us-ascii?Q?zrhJDOVAacB3RYG2VcLlhM8PR25JFnCSC4mINoAPbCSVp8VjH09+7AEwMl3L?= =?us-ascii?Q?14rLpBsxDPoJV+DahguxNxdIP83IyrggJ15bE836Vn5XJLbZL0BSh5dwo0gt?= =?us-ascii?Q?DQoRWAC9hs1B5Ynv3oItfo8X9iLvtgwa9B4q2bRxRWjFAEc9Rwz+ORbkYh02?= =?us-ascii?Q?Gzlw54YefxcupCX67VgnNcpxh5Zzis1s4kRztwY0vPF/LC+qY6eDRQjdi+oe?= =?us-ascii?Q?dLiZ8By6AQO/Jm8ihBMKzVxuiN9XWYdJfZ8620RjbbFO5BbC+RcGbsd0O9E6?= =?us-ascii?Q?3XbpGfK9WWgBqUXdlAXRa4MG/GSYITRDwv5nb+rT5kGJrSJCVU0Py16A3074?= =?us-ascii?Q?mYj8hrpEdAYf1gOx3cyOxh/GGTnLLFmNOPXfpStjjE6s2vD/1FQwrOiZRmC3?= =?us-ascii?Q?zEm0R5vISKIvhXYEiDCzpHYXPX2x0dJEnbV68RuvbdqNoZOJoIgu3ZnFW0F2?= =?us-ascii?Q?U6Rw8Jo/q2U3uHoDzuebWA5OjBS2W2Rre11BWbiCXrFcM25mfrP54/fVBGq5?= =?us-ascii?Q?H7eFBYr5ACU4E0DEtRqYuyvDPJHwk55qs1uDRYgzRnLIuQ+SUTyIY7p+lar5?= =?us-ascii?Q?qlxUbOYtnDyvB5qKvvuMmTXdoDz0sTSRYoWiQ7jw48EpIxPIn+UCpiVi7MnX?= =?us-ascii?Q?N6CDUs3lrCUv82xnhvcyu3gQzOZx6hPz7qEOQfJW/euafHI+/ue/Set8NcZx?= =?us-ascii?Q?HVYmmb17L8Nvttn6eSzLPeoIQxzZrqoEIi92J58SaUTx0snjNv7R49K3eUq/?= =?us-ascii?Q?QXN98rstwNvKuP477R8j3Yd0kdFpRyaGPBpK3UXSRbfFDtan/Ggrs8oIaFJk?= =?us-ascii?Q?iqaoqjtCsMYC4Etlhf3NC5MI1OPEKIQeja4StIGOCRHbJMaLDNwSasEq3Gqw?= =?us-ascii?Q?FYakNAjzdL2Go3Uxbkg8m94H1gCPxC0DD5roh6tyKIl5+3awys1oXAp21wjq?= =?us-ascii?Q?nukbluSwOwU7CQID5dryi/z6ePtNmBvNKyeaQd7Mjpnr0VLs0kKNrxd8GbYM?= =?us-ascii?Q?HGPgD0esseLwwZVMRN0kK0trgUssS/MdnZNBKTUxOtMylxv+NJERHHtvRcxY?= =?us-ascii?Q?1TWU5Ba9nMF6KRnDcQilm7euxdK3Xqmje0MyV1+4b8rLP2YFrSADOTgiVy7y?= =?us-ascii?Q?r780D4ZmGyl/Y0UQHjZRgXy1JbYxLB33RKYQHjgjbYYFeM0JBS2KIf/DampZ?= =?us-ascii?Q?IS6YceALqVvfJhNDXiql7pudgFJPLGsjHerXzDGrzbv/3qnmhds1+mJ6VS1x?= =?us-ascii?Q?2zSvIJnrR6wxgBXSEdzWWkSu6M+8EWPZTK0Qh0xTAhfy57Dgzp3Pa551uH8s?= =?us-ascii?Q?/MQegJ9sugDMgcvH8RaiA4wd6+UDZmb+fRbC/qOV8U+/eqycauBl7Orh1TJI?= =?us-ascii?Q?j9BCe0O4gTnXHy9JQ34g7gaqk2tREQg8f8xeAswyWUCrpKDPBfJSYloGpL6P?= =?us-ascii?Q?GkY2UU2wBi2cLRL/aOyxz1oqhuzdmUO7FfhfuM6X?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: a2db3c6a-5ca7-4235-a489-08dd6d33a3e4 X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 27 Mar 2025 13:31:11.9119 (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: QKpgEigjXdQV171c4EqRvHccGvjhnuNKBaXhk1whoT1+5vdtyqc25NO5YJFXEa6v X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA0PR12MB8695 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250327_063117_026289_DE80C9E5 X-CRM114-Status: GOOD ( 10.52 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Mar 27, 2025 at 10:03:17AM +0000, Pratyush Yadav wrote: > Of course, with the current linked list structure, this cannot work. But > I don't see why we need to have it. I think having a page-table like > structure would be better -- only instead of having PTEs at the lowest > levels, you have the bitmap. Yes, but there is a trade off here of what I could write in 30 mins and what is maximally possible :) The xarray is providing a page table implementation in a library form. I think this whole thing can be optimized, especially the memblock_reserve side, but the idea here is to get started and once we have some data on what the actual preservation workload is then someone can optimize this. Otherwise we are going to be spending months just polishing this one patch without any actual data on where the performance issues and hot spots actually are. Jason