From nobody Tue Oct 7 17:46:31 2025 Received: from forward205d.mail.yandex.net (forward205d.mail.yandex.net [178.154.239.216]) (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 A65DF28724C; Tue, 8 Jul 2025 08:05:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=178.154.239.216 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751961947; cv=none; b=j3NZQMmmkfLHQhax/7FVkvdjHmGA6hQWx9GbAupbN9IAa78zxywQBOuWP1HLuh9fbNzrPLmE66hb+s2UR4cYcbM6Y8RpkjYk1igC2E4qX5NPFyKqr7gArPjFdiztWk9s4r0qGn8TgaK/HiZEMynGMi/In3VJ0QgS813FgCy85D4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751961947; c=relaxed/simple; bh=B9g4G0fmY0TM8gPgXVh0P51IjPxPoN5B1QUDLCyNUbs=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=hYWDB2hJ6BEJxUcF4ies55thoJkYGKHT8Ht6T09kXQzw0yjWjOIdp7Pk+18YnjGYA1aqepBLaCAKVPUsMVlkiINmPrkl1dt/wuiEGluZh7Jn7M3Vqvr20y9Y+SQeFc+yfDxkjy8hc7b9qxfKfU/zBgftkhfJWG4jre6Pw1QYCI0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=onurozkan.dev; spf=pass smtp.mailfrom=onurozkan.dev; dkim=pass (1024-bit key) header.d=onurozkan.dev header.i=@onurozkan.dev header.b=Wz9rjR/r; arc=none smtp.client-ip=178.154.239.216 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=onurozkan.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=onurozkan.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=onurozkan.dev header.i=@onurozkan.dev header.b="Wz9rjR/r" Received: from forward103d.mail.yandex.net (forward103d.mail.yandex.net [IPv6:2a02:6b8:c41:1300:1:45:d181:d103]) by forward205d.mail.yandex.net (Yandex) with ESMTPS id C57B16571A; Tue, 8 Jul 2025 10:59:18 +0300 (MSK) Received: from mail-nwsmtp-smtp-production-main-76.iva.yp-c.yandex.net (mail-nwsmtp-smtp-production-main-76.iva.yp-c.yandex.net [IPv6:2a02:6b8:c0c:bc97:0:640:ee90:0]) by forward103d.mail.yandex.net (Yandex) with ESMTPS id DE2606094D; Tue, 8 Jul 2025 10:59:09 +0300 (MSK) Received: by mail-nwsmtp-smtp-production-main-76.iva.yp-c.yandex.net (smtp/Yandex) with ESMTPSA id qwbJulRMP0U0-RRg8OCpJ; Tue, 08 Jul 2025 10:59:09 +0300 X-Yandex-Fwd: 1 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=onurozkan.dev; s=mail; t=1751961549; bh=HZ89twN1G4Cm9f2TIXMWWBwShVSIJsgKl5vc8RLmyvg=; h=Message-ID:Date:Cc:Subject:To:From; b=Wz9rjR/r7aBSM/7V5wHASnCAA1N08PXykrvUMRt+YjCZwh5sSOIt+7VQiIrGTKEgf JUN7978exZ59oG3Z8YsE6ChjnGeXpld/HJf1Mz4z/qMyWjOMrMV4UlkCqE/gXeLjxy HYjlDZ0dHwPPR7Ij8OVV5AKaMuqJn1ZqoGGFcgbk= Authentication-Results: mail-nwsmtp-smtp-production-main-76.iva.yp-c.yandex.net; dkim=pass header.i=@onurozkan.dev From: =?UTF-8?q?Onur=20=C3=96zkan?= To: rust-for-linux@vger.kernel.org Cc: linux-kernel@vger.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, dakr@kernel.org, mattgilbride@google.com, wedsonaf@gmail.com, daniel@sedlak.dev, tamird@gmail.com, =?UTF-8?q?Onur=20=C3=96zkan?= Subject: [PATCH v2] rust: rbtree: simplify finding `current` in `remove_current` Date: Tue, 8 Jul 2025 10:58:50 +0300 Message-ID: <20250708075850.25789-1-work@onurozkan.dev> X-Mailer: git-send-email 2.50.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable The previous version used a verbose `match` to get `current`, which may be slightly confusing at first glance. This change makes it shorter and more clearly expresses the intent: prefer `next` if available, otherwise fall back to `prev`. Signed-off-by: Onur =C3=96zkan Reviewed-by: Alexandre Courbot Reviewed-by: Alice Ryhl --- rust/kernel/rbtree.rs | 23 +++++++---------------- 1 file changed, 7 insertions(+), 16 deletions(-) diff --git a/rust/kernel/rbtree.rs b/rust/kernel/rbtree.rs index 8d978c896747..58ad52a07c92 100644 --- a/rust/kernel/rbtree.rs +++ b/rust/kernel/rbtree.rs @@ -769,23 +769,14 @@ pub fn remove_current(self) -> (Option, RBTreeN= ode) { // the tree cannot change. By the tree invariant, all nodes are va= lid. unsafe { bindings::rb_erase(&mut (*this).links, addr_of_mut!(self.= tree.root)) }; - let current =3D match (prev, next) { - (_, Some(next)) =3D> next, - (Some(prev), None) =3D> prev, - (None, None) =3D> { - return (None, node); - } - }; + // INVARIANT: + // - `current` is a valid node in the [`RBTree`] pointed to by `se= lf.tree`. + let cursor =3D next.or(prev).map(|current| Self { + current, + tree: self.tree, + }); - ( - // INVARIANT: - // - `current` is a valid node in the [`RBTree`] pointed to by= `self.tree`. - Some(Self { - current, - tree: self.tree, - }), - node, - ) + (cursor, node) } /// Remove the previous node, returning it if it exists. -- 2.50.0