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 BE8DB38DFC; Fri, 9 Feb 2024 16:22:26 +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=1707495746; cv=none; b=FSJKp0xqiJEttqrCFPYbKrr8ydR3U7532GYCuww5UeFjuReYBhf5Nu6Hf93BS4L1MxBLzV6aJxpwusSGIFjcFJeBy26dV4qgnLaLC84bBd7E5QmpOwpxnUO/bBWF/VkSOlZeT8e4N5xciS2LuRcleOVR4d4qrGQNEFag47GEjBc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707495746; c=relaxed/simple; bh=7dF/b+JRFiZgEhiWKo3f6FslMMwH634DNYt0JFfFAHI=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:To:Cc; b=evjAA/kWo+g/J1YjqEKVPkTj6dOVBRbBXy/WRnzctGGOqo2u3Eu4mChnGK0x0L8qjivaldN59NDWB1FEJYFdeXeU2jZyL7LPc1f7xbskU/Aac6/syF/hI9X4MRwwDYLrWJ5TLGKzqwx3h/A2OqPan4ZRLZbdOcJlFWIKQ7Pg8XQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=BZ+bo8+d; 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="BZ+bo8+d" Received: by smtp.kernel.org (Postfix) with ESMTPS id 4D197C433F1; Fri, 9 Feb 2024 16:22:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1707495746; bh=7dF/b+JRFiZgEhiWKo3f6FslMMwH634DNYt0JFfFAHI=; h=From:Date:Subject:To:Cc:Reply-To:From; b=BZ+bo8+dkvZ4tlM2n4uPdxkaMv3EDKqovpEmYIjOOkdhhcXdrZEQU8y0d0hX+hb9Q iHGZgY2yq8ANKwijpNIgBZnXNeXkRdbKev/wg0xv/c/xHCULnE3w5Kr40nrRpJb1p3 CxN/d1241Z9VlWkwHEZWAUyP6D/++IfOdoG/hmjqayijZir+I7vm7k/1onLDSaNuhz hcIYWVlVZGtrtU5JZgOs8VM6tSsx+p4Aa1ZCDClCa5uizjNbyHWwg0K5Ri3bzfnUVO 3HBuA2sizQVirnMUvmeFwpwE2SghWDeESTkgD5AJFO013qVN2o8WYR3vGDBUDnm1p6 qAVwZNA8/iFmg== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 384DCC48297; Fri, 9 Feb 2024 16:22:26 +0000 (UTC) From: Mathys-Gasnier via B4 Relay Date: Fri, 09 Feb 2024 17:22:24 +0100 Subject: [PATCH] rust: locks: Add `get_mut` method to `Lock` Precedence: bulk X-Mailing-List: rust-for-linux@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20240209-rust-locks-get-mut-v1-1-ce351fc3de47@gmail.com> X-B4-Tracking: v=1; b=H4sIAD9RxmUC/x3MSwqAMAwA0atI1gaaUlC8iriQGmvwS1NFEO9uc fkWMw8oR2GFpngg8iUq+5ZBZQF+6rfAKEM2WGOdIaoxnppw2f2sGDjheib0zprKkqGh6iGHR+R R7n/adu/7AZBaGoxkAAAA To: Miguel Ojeda , Alex Gaynor , Wedson Almeida Filho , Boqun Feng , Gary Guo , =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= , Benno Lossin , Andreas Hindborg , Alice Ryhl Cc: rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org, Mathys-Gasnier X-Mailer: b4 0.12.4 X-Developer-Signature: v=1; a=ed25519-sha256; t=1707495746; l=1162; i=mathys35.gasnier@gmail.com; s=20240118; h=from:subject:message-id; bh=BG0YFKP39LR9WWLZKQnZyk4pbHn9EQrD/0InazZ8oWY=; b=kYEX+M8gpUsUd4Tgnh+4FKAf2LwOpTAjIowMb+niPGNSrVk5nRPtPSng1HrJ1ib+p0Jdh5Gal q372/7CHy8aCPVbGpulcJ8Ud4Bdt2SJwWcgQKheYUB03W0kj/oaG8Mo X-Developer-Key: i=mathys35.gasnier@gmail.com; a=ed25519; pk=C5tqKAA3Ua7li5s3a+q2aDelT2j98/yjGg2nEVGArXE= X-Endpoint-Received: by B4 Relay for mathys35.gasnier@gmail.com/20240118 with auth_id=129 X-Original-From: Mathys-Gasnier Reply-To: From: Mathys-Gasnier Having a mutable reference guarantees that no other threads have access to the lock, so we can take advantage of that to grant callers access to the protected data without the the cost of acquiring and releasing the locks. Since the lifetime of the data is tied to the mutable reference, the borrow checker guarantees that the usage is safe. Signed-off-by: Mathys-Gasnier --- rust/kernel/sync/lock.rs | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/rust/kernel/sync/lock.rs b/rust/kernel/sync/lock.rs index f12a684bc957..7711c6313e14 100644 --- a/rust/kernel/sync/lock.rs +++ b/rust/kernel/sync/lock.rs @@ -121,6 +121,11 @@ pub fn lock(&self) -> Guard<'_, T, B> { // SAFETY: The lock was just acquired. unsafe { Guard::new(self, state) } } + + /// Gets the data contained in the lock + pub fn get_mut(&mut self) -> &mut T { + self.data.get_mut() + } } /// A lock guard. --- base-commit: 711cbfc717650532624ca9f56fbaf191bed56e67 change-id: 20240118-rust-locks-get-mut-c42072101d7a Best regards, -- Mathys-Gasnier