From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr1-f74.google.com (mail-wr1-f74.google.com [209.85.221.74]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2481B2E8E17 for ; Fri, 22 Aug 2025 07:59:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.74 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755849543; cv=none; b=lu5jS/P1MiDnL7T+RcjDiBOIJXr0eHC4arJ47Npz6guMFReHRqPZqmuaonr2+r1XGlF7EkUPt6OojCaGExUJy3NLutYdxgC4nYXm/4RbgBa7vxrlDOzsHxEkd9PY0I0fPCXnuZ1wz4XtVSz7mfTnlMKbh77t1Fx4Rn4gChOkuDI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755849543; c=relaxed/simple; bh=ZSQnUiBY+QjVWejECl7qq5B/ncsHvvBk+pJI9WWhJ14=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=CivolxuE8i13T4lqxB9uFfWZTgINMCnEJTirnUjFZ3lhxtq44dlbdnqZPmUryBUtar1muHhqerfUSckFFptayYe8NGC1wdlZNRzK43qP/7EtriuVxhCI6AmDRM6NUE57c8iophK3nZEzRGnUIiPHw2tSs/WtO94BDU92betR2gM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--aliceryhl.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=ePcWKAly; arc=none smtp.client-ip=209.85.221.74 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--aliceryhl.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="ePcWKAly" Received: by mail-wr1-f74.google.com with SMTP id ffacd0b85a97d-3b9e743736dso1034079f8f.3 for ; Fri, 22 Aug 2025 00:59:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1755849539; x=1756454339; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=OcR2vTnWvdHWsTxe8C4S1nf6KTHkxOneetmft7WPD4M=; b=ePcWKAlyd6NH3t/t6bnD3PFKLfRGfImvC3RUidWoW9fND1QrccadYRUIFhBvLuUrPi 1z0Ue9GfuDy/KNWa8BEoiGFtvFqNmhEUTY9y+D3PzJ74RWauKyeLYfeewp5qzsNRZUqS bIdUQ0XcJoKixgiwfNliuylJPblnZOj3Dy/V7TKxxV+DwnPDjZiB5faMhOALFsCcJHV6 4C5ffRZULjmQoWVOnbYds4qrLrkNJD/ifxpbbDbUDF5Rprija7rTnCwHUjJbYV0eI7Sm IJYiApmAZveZKooYwPjEpg1f3A2poSM8EDp8a6T3nmpL5tNLqJpnPe3IhNtbDYhcO6aq v2sQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1755849539; x=1756454339; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=OcR2vTnWvdHWsTxe8C4S1nf6KTHkxOneetmft7WPD4M=; b=DEwBup/9M8TLGict5sbrATN66fIwfTT+Z1yA0BkMUzzEJj7fbVe/MerNRtFe3r3iFK 4RmO6qXSLcJWRvmuGkovzwwqjhSVr+fQQ8hF8zdg5pXzGId7gdSQeHyCNqm4+FU7OU1p MtxbuFZLlsqfogDmj+szHJATV+PB+XDyBPRJEzMIPeAQKbhrjExisLDkbF7pJGt4sMRi ZLnNU1Yo3OpXctakAyEixD0LpmWAnz5cLm5GmFmg+4hbbzL9+hCNUOxf4TaJ+K7V7dp0 v87aguQJg0MgnGdSPyXDkxeU93Kts6ykdl9T2Q7xI4QDQ5pYXj4V0WPl5TmJ8XY7rhFI vnzg== X-Forwarded-Encrypted: i=1; AJvYcCX/lgqUT28iNkZZ5U5oGNOxHbIM42Zk6TBUe5WURL6ivhW3bFTLEQJBdDq0lGuIM2DC/ffAdBfCZQW8jfc=@vger.kernel.org X-Gm-Message-State: AOJu0YyEnxC7pLGg0NHVmeHFr/vjaVmyxUQ5JYRx5n/bH65tCUmpDj8T SOXgaasEZWxT7seMx1K+08rF3dv+hJON+j+N4BdvepxtWcQ5uOT0DHCRitq2UOwOizd6V2o0yJu Np///Et4PzTidatVmgg== X-Google-Smtp-Source: AGHT+IHHa6Gwb6EMwcReUb8w20SMBOY8HUqXKfoIIJGVFOjuon7/sYmIEhsZh0RUa04bS92rGVC4oCZ2kKrrErU= X-Received: from wmbdv11.prod.google.com ([2002:a05:600c:620b:b0:459:dac7:4ea6]) (user=aliceryhl job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6000:2583:b0:3b8:d893:524c with SMTP id ffacd0b85a97d-3c5dcdfb74cmr1360982f8f.53.1755849539448; Fri, 22 Aug 2025 00:58:59 -0700 (PDT) Date: Fri, 22 Aug 2025 07:58:58 +0000 In-Reply-To: <20250821-num-v4-1-1f3a425d7244@nvidia.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250821-num-v4-0-1f3a425d7244@nvidia.com> <20250821-num-v4-1-1f3a425d7244@nvidia.com> Message-ID: Subject: Re: [PATCH v4 1/2] rust: add `Alignment` type From: Alice Ryhl To: Alexandre Courbot Cc: Miguel Ojeda , Alex Gaynor , Boqun Feng , Gary Guo , "=?utf-8?B?QmrDtnJu?= Roy Baron" , Benno Lossin , Andreas Hindborg , Trevor Gross , Danilo Krummrich , linux-kernel@vger.kernel.org, rust-for-linux@vger.kernel.org, nouveau@lists.freedesktop.org Content-Type: text/plain; charset="utf-8" On Thu, Aug 21, 2025 at 09:42:17PM +0900, Alexandre Courbot wrote: > Alignment operations are very common in the kernel. Since they are > always performed using a power-of-two value, enforcing this invariant > through a dedicated type leads to fewer bugs and can improve the > generated code. > > Introduce the `Alignment` type, inspired by the nightly Rust type of the > same name and providing the same interface, and a new `Alignable` trait > allowing unsigned integers to be aligned up or down. > > Signed-off-by: Alexandre Courbot Reviewed-by: Alice Ryhl