From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7C1A9203706; Thu, 26 Jun 2025 20:01:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750968061; cv=none; b=kebGkfBDPhqyiX2AkomfMx4DL37n2Dy40VQq65aIlGXEg+od3vF8QAAlSm4b+p1lxkwfoM6eZIdpdgSMuwQUCIHx+mvS02LrcXzfy6CdBAmHzBn30lm2jKlxLwC0clDh76Gukx3IFHxXuy4PP/G8aBUaJPfP4teIUViXACMYoOc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750968061; c=relaxed/simple; bh=NOy9Y3ciqqS6T9tSszDCtRx8iD4avruD6fPvrBwcEnU=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=LtM9mP0wYgeylT2SSh/aaK2rxotmkTNZZ1PLDYunINSOKdKBjWXZmpQLdwjSIAWC24kwH6RGcuMYyUeQwn1uOu77HKI9a6woe9bVw3JhYqEaMKdI3uWszHY3N2FtEa/PvDiq2jy2DtO9GJ3xY3UMuWrcmxqenqUxYBUjNEtMsnQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=WFkD0Ozu; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="WFkD0Ozu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F2FDEC4CEEB; Thu, 26 Jun 2025 20:00:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1750968061; bh=NOy9Y3ciqqS6T9tSszDCtRx8iD4avruD6fPvrBwcEnU=; h=From:To:Cc:Subject:Date:From; b=WFkD0OzuYSAfTGms9/4M1NA73AYVCJ5kNW5mY+WslIXIceiLMwcMwq+DDcJeutZ9X XAI+Xrpe3yM5ycaoW6WadEBNfONuTuOMbd3Ropiq+tBRsybSOjWhy6yK7pUWr+Em99 b8MyDbuUwHkTjnvBtI5w4AUxbcL43CLU87vos8DSOKZ8GavfILc+gKzuxvAtCFyFYn DS1mfi1tuP20c/S1t56WsBhxelSPUL4xYOWjHD2H+Zfoo57J2nrqm7e/OyGD8ulREW 2SDlJkKZ7gJ4BIwaFwT5ysBz/AR1Aa0ltl0s+I07afvtn5CrWzXpf3XWyZ1Mn2psqu 4Ei7Wt/SIEWMA== From: Danilo Krummrich To: gregkh@linuxfoundation.org, rafael@kernel.org, ojeda@kernel.org, alex.gaynor@gmail.com, boqun.feng@gmail.com, gary@garyguo.net, bjorn3_gh@protonmail.com, lossin@kernel.org, a.hindborg@kernel.org, aliceryhl@google.com, tmgross@umich.edu, david.m.ertman@intel.com, ira.weiny@intel.com, leon@kernel.org, kwilczynski@kernel.org, bhelgaas@google.com Cc: rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, Danilo Krummrich Subject: [PATCH v4 0/5] Improvements for Devres Date: Thu, 26 Jun 2025 22:00:38 +0200 Message-ID: <20250626200054.243480-1-dakr@kernel.org> X-Mailer: git-send-email 2.49.0 Precedence: bulk X-Mailing-List: rust-for-linux@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit This patch series provides some optimizations for Devres: 1) Provide a more lightweight replacement for Devres::new_foreign_owned(). 2) Get rid of Devres' inner Arc and instead consume and provide an impl PinInit instead. Additionally, having the resulting explicit synchronization in Devres::drop() prevents potential subtle undesired side effects of the devres callback dropping the final Arc reference asynchronously within the devres callback. 3) An optimization for when we never need to access the resource or release it manually. Thanks to Alice and Benno for some great offline discussions on this topic. This patch series depends on the Opaque patch in [1] and the pin-init patch in [2], which Benno will provide a signed tag for. A branch containing the patches can be found in [3]. [1] https://lore.kernel.org/lkml/20250610-b4-rust_miscdevice_registrationdata-v6-1-b03f5dfce998@gmail.com/ [2] https://lore.kernel.org/rust-for-linux/20250529081027.297648-2-lossin@kernel.org/ [3] https://git.kernel.org/pub/scm/linux/kernel/git/dakr/linux.git/log/?h=rust/devres Changes in v4: - devres::register: - require T: Send and ForeignOwnable: Send - Devres: - require T: Send - document possible changes when switching from Opaque to UnsafePinned, once possible - devres::register_release(): - rework to Benno's proposal of Release::Ptr - require P::Target: Send - add a patch adding ForeignOwnable::Target, i.e. the type of the payload data (required for devres::register_release()) Changes in v3: - devres::register: - add 'static bound for ForeignOwnable - use drop() instead of `let _ =` - Devres: - use ptr::from_ref() instead of Inner::as_ptr() - use &raw mut instead of addr_of_mut!() - use SAFETY comment proposal from Benno - add invariant for `Devres::inner` - use ScopeGuard in devres_callback() - devres::register_release(): - add impl Release for &T - add 'static bound for ForeignOwnable - use drop() instead of `let _ =` Changes in v2: - Revocable: - remove Error: From bound - devres::register: - rename devres::register_foreign_boxed() to just devres::register() - move T: 'static bound to the function rather than the impl block - Devres: - Fix aliasing issue by using an Opaque; should be UnsafePinned once available. - Add doc-comments for a couple of private fields. - Link Revocable on 'revoke' in Devres::new(). - devres::register_release(): - expand documentation of Release - rename devres::register_foreign_release() for devres::register_release() Danilo Krummrich (5): rust: revocable: support fallible PinInit types rust: devres: replace Devres::new_foreign_owned() rust: devres: get rid of Devres' inner Arc rust: types: ForeignOwnable: Add type Target rust: devres: implement register_release() drivers/gpu/nova-core/driver.rs | 7 +- drivers/gpu/nova-core/gpu.rs | 6 +- rust/helpers/device.c | 7 + rust/kernel/alloc/kbox.rs | 2 + rust/kernel/cpufreq.rs | 11 +- rust/kernel/devres.rs | 361 +++++++++++++++++++++++--------- rust/kernel/drm/driver.rs | 14 +- rust/kernel/pci.rs | 20 +- rust/kernel/revocable.rs | 6 +- rust/kernel/sync/arc.rs | 1 + rust/kernel/types.rs | 4 + samples/rust/rust_driver_pci.rs | 19 +- 12 files changed, 323 insertions(+), 135 deletions(-) base-commit: 7be11f5d927a548254be5c07291b32a6aa50917f -- 2.49.0