From nobody Tue Apr 7 16:29:59 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AB696ECAAD2 for ; Fri, 26 Aug 2022 09:57:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344121AbiHZJ5O (ORCPT ); Fri, 26 Aug 2022 05:57:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40168 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344132AbiHZJ5C (ORCPT ); Fri, 26 Aug 2022 05:57:02 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7B7FCD599C for ; Fri, 26 Aug 2022 02:56:54 -0700 (PDT) Received: from dggpemm500020.china.huawei.com (unknown [172.30.72.54]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4MDZsC1TxyzkWhK; Fri, 26 Aug 2022 17:53:19 +0800 (CST) Received: from dggpemm500006.china.huawei.com (7.185.36.236) by dggpemm500020.china.huawei.com (7.185.36.49) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Fri, 26 Aug 2022 17:56:20 +0800 Received: from thunder-town.china.huawei.com (10.174.178.55) by dggpemm500006.china.huawei.com (7.185.36.236) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Fri, 26 Aug 2022 17:56:20 +0800 From: Zhen Lei To: Catalin Marinas , Will Deacon , Mark Rutland , Russell King , , , CC: Zhen Lei Subject: [PATCH v2 1/2] arm64/traps: Replace this_cpu_* with raw_cpu_* in panic_bad_stack() Date: Fri, 26 Aug 2022 17:51:11 +0800 Message-ID: <20220826095112.289-2-thunder.leizhen@huawei.com> X-Mailer: git-send-email 2.26.0.windows.1 In-Reply-To: <20220826095112.289-1-thunder.leizhen@huawei.com> References: <20220826095112.289-1-thunder.leizhen@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.174.178.55] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggpemm500006.china.huawei.com (7.185.36.236) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" The hardware automatically disable the IRQ interrupt before jumping to the interrupt or exception vector. Therefore, the preempt_disable() operation in this_cpu_read() after macro expansion is unnecessary for exception handler. Use raw_cpu_* instead of this_cpu_* can reduce a few lines of assembly code. To be honest, the fewer unnecessary operations in exception handler, the better. Signed-off-by: Zhen Lei --- arch/arm64/kernel/traps.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index b7fed33981f7b76..e6b6f4650e3d895 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -871,8 +871,8 @@ DEFINE_PER_CPU(unsigned long [OVERFLOW_STACK_SIZE/sizeo= f(long)], overflow_stack) void panic_bad_stack(struct pt_regs *regs, unsigned long esr, unsigned lon= g far) { unsigned long tsk_stk =3D (unsigned long)current->stack; - unsigned long irq_stk =3D (unsigned long)this_cpu_read(irq_stack_ptr); - unsigned long ovf_stk =3D (unsigned long)this_cpu_ptr(overflow_stack); + unsigned long irq_stk =3D (unsigned long)raw_cpu_read(irq_stack_ptr); + unsigned long ovf_stk =3D (unsigned long)raw_cpu_ptr(overflow_stack); =20 console_verbose(); pr_emerg("Insufficient stack space to handle exception!"); --=20 2.25.1