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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?EXf/aMyG24oSv7hfUxa/D7qSMSMVg1zqN2s9HNlBDLDivpDNnQew6YQgXiBH?= =?us-ascii?Q?IM5gXcj2FfykZkuDogUpX+P5VKnUW1Cv25s14naXI2+mC2X7I2gRP3NAtYnN?= =?us-ascii?Q?5/SwPq5x0GJ3DqYIYIGSU/0u3MAtWBi0EqJBTgXMcfLIw3twQ+8579czRYfS?= =?us-ascii?Q?7HRww14vCPpzYagH6jFjgZjkj3z4l/K5dD9s059U9OPiRWtaX3bq5m/uqMey?= =?us-ascii?Q?kEda+9jBuveafOrwqyjXaOYw+2tAjDDDCTHlqtjzgiQ6556yFsCB6DqSUecC?= =?us-ascii?Q?cSTxRTO5qMsH5G5o6nQwVqC3R+V+sNArKhGIlj1P1PT5BfOlBu80kbomSXfX?= =?us-ascii?Q?i3+h8/U+Wq/B7J533iSMVg1AN3HHF6xvYqma5k0+1q1z2Jqvx2CA1QS2h0WO?= =?us-ascii?Q?IBJRbDdL4Sutweh6GcSPdGYkxNX2KChI9d/42cv3vCFzjDQqygy97H3n4ZM+?= =?us-ascii?Q?8MfEdc3wdKQEvZtkTMZoPjSBEoj8g9FgOuAbn8J93BvyoOTJPSEpj7VeZ0pd?= =?us-ascii?Q?XcLMzUNDLRyl7p8J9VlTLX4FAl7EKK+P82qFX4QOrLG/GqHlda35+c0TLAd2?= =?us-ascii?Q?c9WLRgOYVRGX1ceS6znCLZlYjroo8HC9TfhNETBDsT/fFpcstpsfVr72E+EU?= =?us-ascii?Q?7+8HyWBNWs47KCOI2dsd1sZVNqsatr/phiXdmCZar6Sfn9EoC+YiwOufnAQZ?= =?us-ascii?Q?s8IsnXzfKYgNBuyAOPkx6K5UQXZnEu+JA/HAKqb7sE46mN1l8afVyAvksERJ?= =?us-ascii?Q?4agfhfBwP1BNzOUB+3s3nkB0xEG5N4l2jaNn8PVGytdWsoslegS0LqUJfYlN?= =?us-ascii?Q?Wv335vYHoEL8HRy4VoPexppckGM/sO++eX6RnaJaOGzv1zyVZ/KxKniUwPdE?= =?us-ascii?Q?Qy7cavQLnQLBFKoK/a4LZuSSqy2G8LynL7Ar+edWrDNERzAngDVwnj1r9vlH?= =?us-ascii?Q?Roy7iSWPJ4MotHFoZheBiBrVwg0bASMKIT0yYgeUd5DlW9+lzu2GfgW11VtD?= =?us-ascii?Q?gM1NUcBee0utXrSdjeCRT9LyhFZg8MsOSwcgE/ZVb4mIT8IGRKzKaoXp6Tt9?= =?us-ascii?Q?X+DeGkm8uJHE47Nte97U8qJQTALdjlaCgDV4+bxq03f7Kl6Rjvu7TLk7arON?= =?us-ascii?Q?kN2hbq+gsU2vlBhVz86est/qrDRAOG+noscdLamX9uv7Shgi8nlZeCTxGyiy?= =?us-ascii?Q?iWBbqEQp+BAyrZCyXZ+/lU5EJ73MPvPrhYcoiVjqZeeK5Wip4oO1VUowgBiV?= =?us-ascii?Q?+1AU52JY1gS50cbOBrLPho2zt7boEphnZQVrfyxQvdEStAYLIQmccpuT0SYK?= =?us-ascii?Q?sxBMj5T8r09OBs6t1FOGx7w6s9w1ItAc9OuzgAVcHKc1kIfglSttVe+VY2D/?= =?us-ascii?Q?R6/WAH0RHlI8TIKPuAogfKEdOYgM2nT8TBq2a3B865J07MNPO9mwjK0f3Zg3?= =?us-ascii?Q?9Y/FDJ49KtlDM6uDZFqU47fITmqBXZsAGqV9yf2vo6k6U3nHv+Qu1bqYx4We?= =?us-ascii?Q?Te4yYl4EKe9h/2EQPan1StzSq19IvRZScggQ1fo/hKQY1fUge2wOTPZ/OJuq?= =?us-ascii?Q?A/2yJyP/5+itv1Za+QnUHkiqYEyHvQX2ZlwMQiraVO8KvRn9xM+nu6FO7EZV?= =?us-ascii?Q?Ww=3D=3D?= X-OriginatorOrg: garyguo.net X-MS-Exchange-CrossTenant-Network-Message-Id: 8eade774-66e1-4146-40e8-08dce54fa692 X-MS-Exchange-CrossTenant-AuthSource: LO2P265MB5183.GBRP265.PROD.OUTLOOK.COM X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 05 Oct 2024 15:09:04.0829 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: bbc898ad-b10f-4e10-8552-d9377b823d45 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: x7IoEvJ5FHegT45L4x4zia7GH+oDiAzSAuLzbLpRxT0gBcpDvXRGvZBNeQo3NyFMgV6Y3iByupALLjtZDhDCgA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: LO3P265MB1802 On Fri, 04 Oct 2024 20:05:41 +0200 Andreas Hindborg wrote: > Hi Gary, > > "Gary Guo" writes: > > > Currently there's a custom reference counting in `block::mq`, which uses > > `AtomicU64` Rust atomics, and this type doesn't exist on some 32-bit > > architectures. We cannot just change it to use 32-bit atomics, because > > doing so will make it vulnerable to refcount overflow. So switch it to > > use the kernel refcount `kernel::sync::Refcount` instead. > > > > There is an operation needed by `block::mq`, atomically decreasing > > refcount from 2 to 0, which is not available through refcount.h, so > > I exposed `Refcount::as_atomic` which allows accessing the refcount > > directly. > > I would rather wait with this patch until the helper LTO patches land > upstream. Or at least let me run the benchmarks to see the effect of not > inlining these refcount operations. > > Best regards, > Andreas > The helper LTO patch series still need some time. I'd want to be able to test on 32-bit archs in the meantime. Best, Gary