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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?uqkpjpLL+YjN8KfpoQg1fwCA2ik1WBeFj/0wiVq1NqzeqdY9xQlpjwrxnG1o?= =?us-ascii?Q?GF6Erx00904nHe9ioP0gLOdPeqdHvBq3CG7WnvakOKA2UkTUXy7FHB+p/IUx?= =?us-ascii?Q?ri2+PFQnPKMJqZ57EhgSQKGMohOJubPc4XXYGIzyYbPctWihniP8yE2WN8WV?= =?us-ascii?Q?tiqrEpfM2OyfiObvTsr4sli7QsQq4ukCcWeVTNDlySQL5t3L63hpCVCKHnqj?= =?us-ascii?Q?sTo1HvJu92GVFEfVojVaQuQfW3X0d1aDNv0fT5nylbbtmiHgKm72yIuvEHXG?= =?us-ascii?Q?aTt6BIFggH5Qj6b6BBZJgGkDo31cQ9TZMvGgEJh4EP8NDrbmzCuntrB7cvim?= =?us-ascii?Q?Pcsjjhyyo7frVDU5bjWfIp84a0lX6/eqAPcnrzEPk9SZod+Bxl3Gvknk8f9U?= =?us-ascii?Q?+UpPydP8d0DgxCBx9qta2ClJTYAAZJT12SMv/Y1x9UgJ1a2iy2VZVNAZa3rT?= =?us-ascii?Q?UYkskhiFouZ8khqm6SI5J2PLDxw3j25MW4iRe49S1XV4GpXXlSF7i8mmlN08?= =?us-ascii?Q?+feIURvPDHmRvNIPODoy0kRDQQpYm26941N65B2oWGaiPFciYBp8Dk7UTy36?= =?us-ascii?Q?EqWnzqwr6PU9Y0qyEIoQWGQPNamv+/hRxC6AA3b2Xj7H/OQPx5m3prAQckK1?= =?us-ascii?Q?i1nIRV1ojrC4v2e2fhBwI5KtGiPtHMzswql2gPfrGS3AREmSCE5uVkpZfpfb?= =?us-ascii?Q?p+N5mU2Lx8xBQkiCns8robzhk0nUK++6fRjx6CjWHIcKm3lN8V/SANRdFEqv?= =?us-ascii?Q?xzQR/c3zkJffi33aOi4lqBeGVckj8vjOXsRTmbZTQlK6nMUgfOXQAzZ5in2c?= =?us-ascii?Q?265GlNZaA49buAFrDucnJO2THzsLX/rNLPRtIHOzFhFzTm9Hi+io6mXCPu1R?= =?us-ascii?Q?2C4e1dIO8YwQRu8RjkUFdAbSKXTpQ5x+jvdf6fTimomZCePzJC4tD7PWIbDg?= =?us-ascii?Q?Yx/rhAt2frjvDxVW+HzjX/0/83D5vz8KQsNDbagnwYnZw3zCxlfp8b+4HE/3?= =?us-ascii?Q?KAouY1BX9o74bctUzNNJt79R21Xe0lSoe/5u2cPsGUYcIp2btHTv59gVrg+0?= =?us-ascii?Q?DXnRVpdMGckZvn2yBuQ6vw9sRaRdNj53KPPwbppLHVq36CVsOBhScUHTQz5i?= =?us-ascii?Q?fiCf2uCT3v74waxsdUhkqkIEAvy+3Yg0vkR8aGkScmqtWmllFXUiYONqLb31?= =?us-ascii?Q?oj43AnE7/2O6x0posEYSmTHY29RJ0mhyp4QKsm2EBQMMS4x+wnVu4yVPqmd4?= =?us-ascii?Q?L7T3yltKrrKkutgVGfgACrRgXhPB13dFrxpgjEcx1KWeGk3bl+LZ+YYJAVqn?= =?us-ascii?Q?cVJ7vOk6HdbPVT4XWqoo/hD0/B/MvRUd1oN0keCqKdMafIsLTJ5doofBN4Sm?= =?us-ascii?Q?fRicM+9uRedM3EvCR/9IkKWQhhIxiTECZ9TEAwqdapk+TOK97XIqU/NpP+SG?= =?us-ascii?Q?xZiXyYEwHWiI5FxDWt9pAFKcToC1LY/kZ+fUh3CTV7HSMo6jMYjZvfhDmvIU?= =?us-ascii?Q?WrLNvFlMlxhVIjk3vJPO+0EBNFm1xTZn9sEytqUjXIXLGxwkPB+V8AW7M60K?= =?us-ascii?Q?Z76anFpxsF7cayAzjblW9bbVNZLnv0Vg3vfSH/f8CQLaGB/XYgyS/kmVy4yw?= =?us-ascii?Q?AA=3D=3D?= X-OriginatorOrg: memverge.com X-MS-Exchange-CrossTenant-Network-Message-Id: d3c876c9-855b-4da4-c9d4-08dbcabcd1e0 X-MS-Exchange-CrossTenant-AuthSource: SJ0PR17MB5512.namprd17.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 12 Oct 2023 00:47:32.8664 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 5c90cb59-37e7-4c81-9c07-00473d5fb682 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: I5pstMBzTWZ7nsgJCy2dn6orQDPxjC0am7k4Zw3bqJ0wQfzeuV5W4NILJ3GVJx4xJ3a2/TZCKTmsdXqe36BZ+owl31M28hKtIS9aFAE62lY= X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW4PR17MB5926 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 11, 2023 at 10:15:02PM +0100, Matthew Wilcox wrote: > On Mon, Oct 09, 2023 at 04:42:56PM -0400, Gregory Price wrote: > > == Mutex to Semaphore change: > > > > The memory tiering subsystem is extended in this patch set to have > > externally available information (weights), and therefore additional > > controls need to be added to ensure values are not changed (or tiers > > changed/added/removed) during various calculations. > > > > Since it is expected that many threads will be accessing this data > > during allocations, a mutex is not appropriate. > > > > Since write-updates (weight changes, hotplug events) are rare events, > > a simple rw semaphore is sufficient. > > Given how you're using it, wouldn't the existing RCU mechanism be > better than converting this to an rwsem? > ... yes, and a smarter person would have just done that first :P derp derp, thanks, I'll update. ~Gregory