From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 7E1B73630B0; Tue, 26 May 2026 15:22:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779808943; cv=none; b=WK76XlsP+NHNy2Uzav1j6jrkrSVq9sOo/UX7VAc07918etIOK246g92SXaZz5BVRsp8Ir73pubyxkDTXyLx2s4uFt4IsfDSN+H5Uuq7w06R09Uqi6dKeXC0ThjA5CnDv1keiOdk77HU/u2Q2WYEBX9QYFVc5LsOJ84IoeLONmbg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779808943; c=relaxed/simple; bh=Z82SRTfViDGMogbdljsdRjgJQzLo4HNgFr7e4VKosb0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XBctrkf9Amw3a0ZXjWnaaB8N4wAySsA+08TDEwv9LlGeKlTNEZ9/3+f6aaoqRZo7si02zaZrBaDJImHdrAd+BXrxG63g1J7CyCCdJcsbGMuhkxTbrlnrjxTx5CDjA5OvEYOQotCpz6wXFb3Gs8BNHvf+eR2iIULiem7xBWmEJy0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=WtyQFD8v; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="WtyQFD8v" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5EEE41F00A3F; Tue, 26 May 2026 15:22:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1779808942; bh=v42NgC0fdcn56Nn20BKSdfY3OACyeZqMYj+lGiSubwU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=WtyQFD8vvtCxm7dwqYrHmP3rRVBhk2Z4Mtj7BasO4pF9yghxfXRaZJa/oiVvL7p/W vuAuEb6LlfM2bSthdzDsUENc6mO5UI999qaGFWnQQystTeBfrZWrSf/j0f5WT9hPQk FbUZmXb+x5KUgpuzveJfJsTk2SuP+p6NVOeNeBAJ5F0phZUn6d4h8UE08QEGeZDKfL K6vjDDN9ZQ7zwrYAb9V8QaEMm7upjI9zGmlc0FbXGUH+wTkOuQmDgfBVIkRIhkLpNl TA4AzVmBdqo0/Gt4uVjKtddeVjOVHDayhsVdM2/KMvUndwfb6smOwQ/msv8TacsoLj B+FTgRvF9A5og== Received: from phl-compute-04.internal (phl-compute-04.internal [10.202.2.44]) by mailfauth.phl.internal (Postfix) with ESMTP id ABCF7F40088; Tue, 26 May 2026 11:22:19 -0400 (EDT) Received: from phl-frontend-03 ([10.202.2.162]) by phl-compute-04.internal (MEProxy); Tue, 26 May 2026 11:22:19 -0400 X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: dmFkZTFpmA1McbnqjIdDoCcC8/dKh9RDeYcaA/XB6dgQZoHsdisS7Rnte/RUY2pDCqsaCf lYH/GXfkGRmzTYnB4S+g0DoIzy4KUSXH1v1hqWsXA4v5WIAvvT6c8zNgUsod23Kpq2+47O yYMzbMVdimQJPpKCDvwUMQiSwLgkBGzQ1ckebHI5CwcU5PXtm0paPap1/zDmdG+vWcQc/M pmWI2idDed0xMRSQV9XOsN/PBFcH6SBYELvyO/AtrMtpHg8r71AQlMzDlEp1H1iVazK3oS DonyrliF9qRbQD87XBn6QOt2bC/09pqeijaNsBJFU0GwQ/sar+bEYdVoRVtkXuEiBwHIVJ +vPnz7YRz2gRtfvdleAquLDzEvrynvx94NYhsHKQkHBAYDBJmTuhALx1WmJ0oQVkmj5ABW UtUh4XZureKmq68D7B+MJ1NE+qtTkPqUsgs7UFLReMFU7Uth479W+ocM97I1qfPl/F1LhS qloIyRSVZETQHrb0OqeC+IKcktI/o29cw0IsNSiQA6VV8Q0gO+9Yi7oaA9mx+x7RScD0EK 0KiuLh09SFrpIterdpQufJFc6lDZrOnzg5g5/cHE5HDzrM4BqcRXMrbhIbyKelQv1rW4s+ QKJKBJTXjKVO4MrZ1Qe0AuVk6j53/jm5tPzZ4bafWuOsGC/UB6YsUeyJ+meA X-ME-Proxy: Feedback-ID: i8dbe485b:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Tue, 26 May 2026 11:22:18 -0400 (EDT) From: Boqun Feng To: Peter Zijlstra Cc: Catalin Marinas , Will Deacon , Jonas Bonn , Stefan Kristiansson , Stafford Horne , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Arnd Bergmann , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , K Prateek Nayak , Boqun Feng , Waiman Long , Andrew Morton , Andrii Nakryiko , Eduard Zingerman , Alexei Starovoitov , Daniel Borkmann , Martin KaFai Lau , Kumar Kartikeya Dwivedi , Song Liu , Yonghong Song , Jiri Olsa , Shuah Khan , Miguel Ojeda , Gary Guo , =?UTF-8?q?Bj=C3=B6rn=20Roy=20Baron?= , Benno Lossin , Andreas Hindborg , Alice Ryhl , Trevor Gross , Danilo Krummrich , Jinjie Ruan , Lyude Paul , Thomas Huth , Sohil Mehta , "Xin Li (Intel)" , Pawan Gupta , Nikunj A Dadhania , Joel Fernandes , Andy Shevchenko , Randy Dunlap , Yury Norov , Sebastian Andrzej Siewior , linux-kernel@vger.kernel.org, linux-openrisc@vger.kernel.org, linux-s390@vger.kernel.org, linux-arch@vger.kernel.org, bpf@vger.kernel.org, linux-kselftest@vger.kernel.org, rust-for-linux@vger.kernel.org, =?UTF-8?q?Onur=20=C3=96zkan?= , Daniel Almeida Subject: [PATCH v2 11/12] arm64: sched/preempt: Enable HAS_SEPARATE_PREEMPT_RESCHED_BITS Date: Tue, 26 May 2026 08:21:47 -0700 Message-ID: <20260526152148.30514-12-boqun@kernel.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20260526152148.30514-1-boqun@kernel.org> References: <20260526152148.30514-1-boqun@kernel.org> 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 ARM64 already uses 64bit preempt count and the need reschedule bit is maintained in a separate 32bit than the preempt count. Therefore preempt count has enough bits to represent 16 level of NMI nesting, hence enable it for ARM64. This saves a per-CPU variable and additional instructions in the NMI path. Signed-off-by: Boqun Feng --- arch/arm64/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index fe60738e5943..8178cb857115 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -248,6 +248,7 @@ config ARM64 select PCI_SYSCALL if PCI select POWER_RESET select POWER_SUPPLY + select HAS_SEPARATE_PREEMPT_RESCHED_BITS select SPARSE_IRQ select SWIOTLB select SYSCTL_EXCEPTION_TRACE -- 2.50.1 (Apple Git-155)