From nobody Sat Feb 7 08:02:25 2026 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 269BE3A4F5A for ; Wed, 21 Jan 2026 22:40:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769035251; cv=none; b=dPTQYHNh7kPOza0CRsRW2l7j1TZqdq35hd9nQKX/M7wHyEg1aXfJpApr3yOA4iwcOPL1bfO5lvzkUI6u4dRs1M3GHLpxX3T9IduNETCW7PFYX6Am3jqZvPQX+88Yh5MTlvxKSW1idJrfyk3G1QgeKIluKOAOqCMLeob0OB/RgYg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769035251; c=relaxed/simple; bh=3//OycOmD4rBumI17D3kBTe6WK01LnbBe128wnNQEvA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Gc/gSsl33wK5hGZNse1MXG1/swf8JFDjwjWmKtI+9QFIdcLXg8Sn9D70o4L7TXqqmKstvwNG7mdU/Pq9MUqZEXo1fcwFQ9J7D7gqLinjuzWNUdNzf24eDzCzdktB3M9Z/EPi0k8KO9Inom3D3igQvHmHEnJc88EF3ytNNZKdzKY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=WJQmtspm; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="WJQmtspm" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1769035242; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=PfPmdWNG75YWfsGCPexjvl6kzyToE8Zc5DDeinRfGW0=; b=WJQmtspm/jcj4JRzWR8ZKxH1+cPEl9d7R3m5IWZPTSE91vx7hMqhNxZvx1BFo8RXJ8sHgj CJbzAxauNxDrbpBmM/PU+DO99foI5jS9E/ubU5MaQG8L9LXowgE4n3Vv1fwnzwRQiaBGhW a2qDbqr7MDPd/h5TNfxQxpQccV+/m/k= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-94-V--cIc5pMGaCi0y-zM3wHQ-1; Wed, 21 Jan 2026 17:40:36 -0500 X-MC-Unique: V--cIc5pMGaCi0y-zM3wHQ-1 X-Mimecast-MFC-AGG-ID: V--cIc5pMGaCi0y-zM3wHQ_1769035234 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 97696180034A; Wed, 21 Jan 2026 22:40:34 +0000 (UTC) Received: from GoldenWind.redhat.com (unknown [10.22.89.232]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id C44C419560AB; Wed, 21 Jan 2026 22:40:31 +0000 (UTC) From: Lyude Paul To: rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org, Thomas Gleixner Cc: Boqun Feng , Daniel Almeida , Miguel Ojeda , Alex Gaynor , Gary Guo , =?UTF-8?q?Bj=C3=B6rn=20Roy=20Baron?= , Benno Lossin , Andreas Hindborg , Alice Ryhl , Trevor Gross , Danilo Krummrich , Andrew Morton , Peter Zijlstra , Ingo Molnar , Will Deacon , Waiman Long Subject: [PATCH v17 14/16] rust: sync: lock/global: Add Backend parameter to GlobalGuard Date: Wed, 21 Jan 2026 17:39:17 -0500 Message-ID: <20260121223933.1568682-15-lyude@redhat.com> In-Reply-To: <20260121223933.1568682-1-lyude@redhat.com> References: <20260121223933.1568682-1-lyude@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Content-Type: text/plain; charset="utf-8" Due to the introduction of sync::lock::Backend::Context, it's now possible for normal locks to return a Guard with a different Backend than their respective lock (e.g. Backend::BackendInContext). We want to be able to support global locks with contexts as well, so add a trait bound to explicitly specify which Backend is in use for a GlobalGuard. Signed-off-by: Lyude Paul Reviewed-by: Benno Lossin --- V17: * Add default parameter for generic `B` to `GlobalGuard` rust/kernel/sync/lock/global.rs | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/rust/kernel/sync/lock/global.rs b/rust/kernel/sync/lock/global= .rs index be17a30c66bf8..94f6b3b21324f 100644 --- a/rust/kernel/sync/lock/global.rs +++ b/rust/kernel/sync/lock/global.rs @@ -77,14 +77,14 @@ pub unsafe fn init(&'static self) { } =20 /// Lock this global lock. - pub fn lock(&'static self) -> GlobalGuard<'static, G> { + pub fn lock(&'static self) -> GlobalGuard<'static, G, G::Backend> { GlobalGuard { inner: self.inner.lock(), } } =20 /// Try to lock this global lock. - pub fn try_lock(&'static self) -> Option> { + pub fn try_lock(&'static self) -> Option> { Some(GlobalGuard { inner: self.inner.try_lock()?, }) @@ -94,11 +94,11 @@ pub fn try_lock(&'static self) -> Option> { /// A guard for a [`GlobalLock`]. /// /// See [`global_lock!`] for examples. -pub struct GlobalGuard<'a, G: GlobalLockBackend> { - inner: Guard<'a, G::Item, G::Backend>, +pub struct GlobalGuard<'a, G: GlobalLockBackend, B: Backend =3D ::Backend> { + inner: Guard<'a, G::Item, B>, } =20 -impl<'a, G: GlobalLockBackend> core::ops::Deref for GlobalGuard<'a, G> { +impl<'a, G: GlobalLockBackend, B: Backend> core::ops::Deref for GlobalGuar= d<'a, G, B> { type Target =3D G::Item; =20 fn deref(&self) -> &Self::Target { @@ -106,7 +106,7 @@ fn deref(&self) -> &Self::Target { } } =20 -impl<'a, G: GlobalLockBackend> core::ops::DerefMut for GlobalGuard<'a, G> +impl<'a, G: GlobalLockBackend, B: Backend> core::ops::DerefMut for GlobalG= uard<'a, G, B> where G::Item: Unpin, { @@ -157,7 +157,7 @@ impl GlobalLockedBy { /// Access the value immutably. /// /// The caller must prove shared access to the lock. - pub fn as_ref<'a>(&'a self, _guard: &'a GlobalGuard<'_, G>) -> &'a T { + pub fn as_ref<'a, B: Backend>(&'a self, _guard: &'a GlobalGuard<'_, G,= B>) -> &'a T { // SAFETY: The lock is globally unique, so there can only be one g= uard. unsafe { &*self.value.get() } } @@ -165,7 +165,7 @@ pub fn as_ref<'a>(&'a self, _guard: &'a GlobalGuard<'_,= G>) -> &'a T { /// Access the value mutably. /// /// The caller must prove shared exclusive to the lock. - pub fn as_mut<'a>(&'a self, _guard: &'a mut GlobalGuard<'_, G>) -> &'a= mut T { + pub fn as_mut<'a, B: Backend>(&'a self, _guard: &'a mut GlobalGuard<'_= , G, B>) -> &'a mut T { // SAFETY: The lock is globally unique, so there can only be one g= uard. unsafe { &mut *self.value.get() } } @@ -219,7 +219,7 @@ pub fn get_mut(&mut self) -> &mut T { /// ``` /// # mod ex { /// # use kernel::prelude::*; -/// use kernel::sync::{GlobalGuard, GlobalLockedBy}; +/// use kernel::sync::{Backend, GlobalGuard, GlobalLockedBy}; /// /// kernel::sync::global_lock! { /// // SAFETY: Initialized in module initializer before first use. @@ -235,7 +235,7 @@ pub fn get_mut(&mut self) -> &mut T { /// /// Increment the counter in this instance. /// /// /// /// The caller must hold the `MY_MUTEX` mutex. -/// fn increment(&self, guard: &mut GlobalGuard<'_, MY_MUTEX>) -> u32 { +/// fn increment(&self, guard: &mut GlobalGuard<'_, MY_MUT= EX, B>) -> u32 { /// let my_counter =3D self.my_counter.as_mut(guard); /// *my_counter +=3D 1; /// *my_counter --=20 2.52.0