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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?ngsba5uDKcSJhYHfsSt2KGB3V6vyXwrM7pNEpSPmxP4nKsMlq4+G+vIk1VRT?= =?us-ascii?Q?SJwC1oaMcbzSsAcD+cbg8yf6MzI3NU6Hl09DbFoWypkJJFj0pRLFv+psl+sM?= =?us-ascii?Q?QDekt9Spd9NGaL0BWAqSMl5p1v5Hp/5cYJFLXG1hhUS76yYxmUWlBwoPytZY?= =?us-ascii?Q?cZrDr5Jf8ydIHo62m9e4x0BZDg0c4WlJXNVg4/+h8/6gGa0Z0nDl2ClIIYVT?= =?us-ascii?Q?HOGdAa/nuDuWhMmLmpvWE5dlAuJt8RE79UNzlLycWbAHKzgLuV8W9okRFGAB?= =?us-ascii?Q?DswgsnHKOrBw0dZp5YcqpqoA4tzjZoYmmwZ+6ysi2IYavvUZYQUcrcCTWF4Y?= =?us-ascii?Q?RKUOEoxybgVmWc4zU49Nqo3Br+gBHbMKbQTvD1w1hd1u8Id5D2B5ozwsmZZo?= =?us-ascii?Q?Y0PrxeHE02DfC/j1YtWivznDspRbfRqrQFhMIClJRZJAXzx7UfYCpHjJyLEB?= =?us-ascii?Q?8cf5O4PV1bCJBCDZOBrSAquALNvoIJFU8tQFXOSSa8PLN4QUSrcg7nOGoFqT?= =?us-ascii?Q?bVRJtSwJFLqW/UvWWucqjTD94FXBOV/DY/ZAh3Uqu8T3YfVTFD3OCJxV0Ct7?= =?us-ascii?Q?KXAY0g3XpKSy00D9P2RiPivy6IhCl4Adzxq5auyAra8Y2qec2kmln23iXFwx?= =?us-ascii?Q?+qKoMfGiA7Vf+dfwT7ITTZUsGpyo/UqM22ZAbvlGtTLSvFcOctQVciATEYO+?= =?us-ascii?Q?urB1OWmJED7vcP8UJZqWzwOgAkkL7Xp8C7OhZjXuZCgf4zaprvk96LG0+bkU?= =?us-ascii?Q?L5owoOmkMRqXsdcYGrwgA4cSgo19sZZThg8//7NSinCTdWIYSvEE1YNv7u7L?= =?us-ascii?Q?ORiK9Zo3UugiN6qemYmAqPowhgMzSbmP0B0xtxEk8mNjWQQoovNSMt1qgPEU?= =?us-ascii?Q?gCUjs7Adujdq3HFJU1WVYK5bR0A7r6Rb4SutS+8zTBT51QmAv4FNqMgzuBuK?= =?us-ascii?Q?onAOdiJs2RntolFCeLGAv6nvUeEm9Nj7Crxl1FxA7PtuQ0Sn2e2Q6syTsAyR?= =?us-ascii?Q?tdEnuWo95cx00og+TyQkuqJZAz+Jz0PTfNZrEsSQQenHzFvLm5QOvZgpPfoB?= =?us-ascii?Q?1JIVbMYle5EF6LfevufAyL78uCSv2NOG2pQtExWPoExFVFVwPNQ9GWfowrLR?= =?us-ascii?Q?RLZ1arNwlww385D0p+uAej1aeGnGjv/hyClZXhsZPREpjzpMu0Ee4FAEaeqY?= =?us-ascii?Q?QzfS0xgjOnxMNEhEl/cUQekwvIIwYs812ReEIgzUaxIt+4o4cV3q0VgEaNDa?= =?us-ascii?Q?BqhJRTKfyAos8b5jWf02n6sWqZF8/1HRM35g1qwJqQntB+NowdNoDyLZ4g4X?= =?us-ascii?Q?ir7XxwavlpnN3QIQZssa4g3WHff1wnVpkJQ4esGFMSnmPWGj8nomT8Krw/hO?= =?us-ascii?Q?Lr+tSwAd5PMP96sIRemmMmiV25kngC5YXrJZqkKQsF4OdI4GO21ZJ6xUXr/m?= =?us-ascii?Q?CZQJZzSNps6CuY53vD0+HKEd+83iL267Br3n1mSXW4RBceOd/8I7Hd8mFNAt?= =?us-ascii?Q?HNJOFmrfZT97bj+b6f6gf2t02b1uiXdxiz4jSwKO++mJr6TibHnakYMFRv0k?= =?us-ascii?Q?MjCAOjS65OfZJluCG15Y2tjNDx9tJi2eUqDrGSC3C6rQ6Ib5nfBNu6ZbHe7k?= =?us-ascii?Q?XoaEqrUe38R6gCZ84CkOm0cQNt1mea4PEZ/CvEbj4Bwrvx0Ps2D3UtXBg4jZ?= =?us-ascii?Q?IPJm/948vvta83MY2y91LCXFYr9oVL48y3GZ0Hp6GcsfOu7vzil8kTfcFYSw?= =?us-ascii?Q?JhwlRgPC0g=3D=3D?= X-OriginatorOrg: garyguo.net X-MS-Exchange-CrossTenant-Network-Message-Id: cf4a50a1-ed74-4846-bf3a-08de488218fb X-MS-Exchange-CrossTenant-AuthSource: LOVP265MB8871.GBRP265.PROD.OUTLOOK.COM X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 31 Dec 2025 15:34:33.6173 (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: UBOMWwecjeo2zKsw3L9CP7UpeXqX9Mn1UgN6jIZsT5QFKFkxx+35b34Nn+8XFCfY72EELCgYkCDDAZCkgm8kOw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: LO2P265MB2784 On Tue, 30 Dec 2025 13:50:26 +0900 FUJITA Tomonori wrote: > This adds `bool` support to the Rust LKMM atomics. > > Rust specifies that `bool` has size 1 and alignment 1 [1], so it can > be represented using an `i8` backing type. > > Since `bool` only permits the bit patterns 0x00 and 0x01, the first > patch also documents an additional safety preconditions for unsafe > `Atomic::::from_ptr`. > > `from_ptr()` exists to operate on C-side storage so I don't think it > makes sense for bool. We could restrict from_ptr() via a marker trait. The C-side does have `bool` type, too (`_Bool` has been there since C99 and we have typedef'd it to `bool`). User might still want to perform relaxed load/store on these C-side bool storage. I think it's fine to leave out this line too (given Boqun also points out that the additional safety precondition is not needed for `from_ptr). Best, Gary > > [1] https://doc.rust-lang.org/reference/types/boolean.html > > > FUJITA Tomonori (2): > rust: sync: atomic: Add atomic bool support via i8 representation > rust: sync: atomic: Add atomic bool tests > > rust/kernel/sync/atomic.rs | 1 + > rust/kernel/sync/atomic/internal.rs | 8 ++++++++ > rust/kernel/sync/atomic/predefine.rs | 27 +++++++++++++++++++++++++++ > 3 files changed, 36 insertions(+) > > base-commit: 13ade169e801a423bc1a5a5c3c6ac680a144a608