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charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Rspam-User: X-Stat-Signature: xrfk3t881kiu5t17zsrhuruy5ki11uag X-Rspamd-Queue-Id: 747A240008 X-Rspamd-Server: rspam11 X-HE-Tag: 1725996832-584257 X-HE-Meta: U2FsdGVkX18khSIypCrjdeGr7p/HjVHSK8YBRKcQ7KE7rJAP4wxPY96VRXLdsLQMzRmgyRhazClAvUnVe2/AYiRTA993L0nB/XeSPo2pgxqF8p1cxkDUfm/5vqh9XOiObzI9TIN7uMMmuPp7Mig7GKJoOV1HahNRBrM5VEKm4CtVd5KezAx5eu9veQARXY6iEbjHUWHfv/q9N2VBl6PYMmwRdc+HQGi+ZNyN/HtrMTsPJL++LZnFuKgVXHXG+ZeIP8x8su4CSt87oPKe7bkEqvs+injLi0PcN32iesNZq8bjMQ7SYf2iIqdx3Zs1az+IyAyvKOEOwUb5trGYaoQNvg0lmb3xWSLpUJrinhq15jp4+FjghBJVT+fPotR7gL/5TVszcAg7nEpVBKKZ3WFcEuBRJlYdT0VYzqggoXjRGoFw8n/TrcSVyPZfjjhjjuDeQRgWcnOitV0So5YYKHk1Zfaiui9hguWEbZArbVIddSvCTpFBRoJmLDYlJ1u7KDB/Qxri2/mAcS0llXjgRd1NbSf7j78eCk1bWWo6lQMeTUpd2bUwut2WMJgsVeZ3skT7rZZ0K6SD+Dk2sgmTsgVkZu45tFBDiNC0EH2fV9qZ8EO756IHBV8fUt2pOhtPx1LaObuC3mNpOK/bXgC66dtH63nBGdOFDDBciVLGecpfW3VGQ/TJDOmJCeDUVhYp6KqQw4g95Wfk7isedkUfNI398BrFkny6Mh9Tt9xc2MEQBl5xtA4jAK2Bav8VxDOiBREtVkGeTozn/Ti6nh+BsKu+2xcGSXAryetHFRy5wKkPUb2euZ3/NyNSupKEQbX0BXP/6KoNIQsLX7/z1zfR5RzagiSQBFsEQZrH8hcmDn77EKSCu3noMw9N+VbDhBTsBdy2ZtIFz5qOP15Oakl5xczKIxAJV2Ukt4C2TIoRjJiQVHEkCucWf6Q+5fhLFvvnhxow7b8TO5E1nfBCZqZIPbA VEO/iX9O ahvWn0FwVrTZNldrd+IgkcxzbiugViWTAXYjnTST75FBU6dVqqJzhtuUbZeKq2RPdvzTGYdRI2+VI01769pQm+wl8rYYpBHX9nKHrjX+oTMFqzOrwM+j/ZLMz4idnMOnP6p9A5yVdctQAJX9BlHyC41WJhPuofC4vvXCZNuQdRgN2TF2KLUWvoupbaV4hrijhqyNIOc8c6F05ZtXBZMhb2uio4wTsTgrNIbJGtpochFx79PsjPyUSTdJY/mU8GKAHeKHVADYGH061FBMYtVHcQq/jga1dFo5+G/UIBGVst960vsB3PTa0TGHJqQTpCC6MIKDhrJSCW+4ArERfvVskmc1F5udFE54kzwOGnX/m4i3wh0f0p/Gv1ccpX7N8IyCOit9Z31k2jOr594io2D1bUQhKSg== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000001, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 10.09.24 20:26, Danilo Krummrich wrote: > On Tue, Sep 03, 2024 at 12:08:08PM -0700, Boqun Feng wrote: >> On Fri, Aug 16, 2024 at 02:10:55AM +0200, Danilo Krummrich wrote: >>> `Vec` provides a contiguous growable array type (such as `Vec`) with >>> contents allocated with the kernel's allocators (e.g. `Kmalloc`, >>> `Vmalloc` or `KVmalloc`). >>> >>> In contrast to Rust's `Vec` type, the kernel `Vec` type considers the >>> kernel's GFP flags for all appropriate functions, always reports >>> allocation failures through `Result<_, AllocError>` and remains >>> independent from unstable features. >>> >>> Signed-off-by: Danilo Krummrich >>> --- >> [...] >>> + >>> +impl Vec >>> +where >>> + A: Allocator, >>> +{ >> [...] >>> + /// Forcefully sets `self.len` to `new_len`. >>> + /// >>> + /// # Safety >>> + /// >>> + /// - `new_len` must be less than or equal to [`Self::capacity`]. >>> + /// - If `new_len` is greater than `self.len`, all elements within= the interval >>> + /// [`self.len`,`new_len`] must be initialized. >> >> Maybe use "[`self.len`, `new_len`)" to indicate `new_len` side is open? >=20 > Agreed. Alternatively just use the rust range operator `self.len..new_len`, it is exclusive by default (for an inclusive range you can use `..=3D`). >> Also `self.len` may confuse people whether it's the old length or new >> length, could you use `old_len` and add note saying "`old_len` is the >> length before `set_len()`? I personally think this is not a big issue, since safety requirements are preconditions to calling a function (so the function couldn't have been called yet). > What about: >=20 > /// - If `new_len` is greater than `self.len` (from before calling thi= s function), all elements > /// within the interval [`self.len`,`new_len`] must be initialized. You will still apply the range fix, right? --- Cheers, Benno