From mboxrd@z Thu Jan 1 00:00:00 1970 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 D8DFDEEAA4F for ; Thu, 14 Sep 2023 14:41:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238205AbjINOlU (ORCPT ); Thu, 14 Sep 2023 10:41:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45666 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240273AbjINOlS (ORCPT ); Thu, 14 Sep 2023 10:41:18 -0400 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6EEDE1BE1; Thu, 14 Sep 2023 07:41:14 -0700 (PDT) Received: from lhrpeml500005.china.huawei.com (unknown [172.18.147.201]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4Rmfyl2yvtz6J7Pn; Thu, 14 Sep 2023 22:36:31 +0800 (CST) Received: from localhost (10.202.227.76) by lhrpeml500005.china.huawei.com (7.191.163.240) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Thu, 14 Sep 2023 15:41:12 +0100 Date: Thu, 14 Sep 2023 15:41:11 +0100 From: Jonathan Cameron To: James Morse CC: , , , , , , , , , Salil Mehta , Russell King , Jean-Philippe Brucker , , Subject: Re: [RFC PATCH v2 25/35] LoongArch: Use the __weak version of arch_unregister_cpu() Message-ID: <20230914154111.0000189d@Huawei.com> In-Reply-To: <20230913163823.7880-26-james.morse@arm.com> References: <20230913163823.7880-1-james.morse@arm.com> <20230913163823.7880-26-james.morse@arm.com> Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 4.1.0 (GTK 3.24.33; x86_64-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.202.227.76] X-ClientProxiedBy: lhrpeml500006.china.huawei.com (7.191.161.198) To lhrpeml500005.china.huawei.com (7.191.163.240) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org On Wed, 13 Sep 2023 16:38:13 +0000 James Morse wrote: > LoongArch provides its own arch_unregister_cpu(). This clears the > hotpluggable flag, then unregisters the CPU. > > It isn't necessary to clear the hotpluggable flag when unregistering > a cpu. unregister_cpu() writes NULL to the percpu cpu_sys_devices > pointer, meaning cpu_is_hotpluggable() will return false, as > get_cpu_device() has returned NULL. Thought that looked odd earlier but didn't care enough to dig. Seem unlikely state would persist for an unregistered cpu. Great to see confirmation. > > Remove arch_unregister_cpu() and use the __weak version. > > Signed-off-by: James Morse Reviewed-by: Jonathan Cameron > --- > arch/loongarch/kernel/topology.c | 9 --------- > 1 file changed, 9 deletions(-) > > diff --git a/arch/loongarch/kernel/topology.c b/arch/loongarch/kernel/topology.c > index 8e4441c1ff39..5a75e2cc0848 100644 > --- a/arch/loongarch/kernel/topology.c > +++ b/arch/loongarch/kernel/topology.c > @@ -16,13 +16,4 @@ int arch_register_cpu(int cpu) > return register_cpu(c, cpu); > } > EXPORT_SYMBOL(arch_register_cpu); > - > -void arch_unregister_cpu(int cpu) > -{ > - struct cpu *c = &per_cpu(cpu_devices, cpu); > - > - c->hotpluggable = 0; > - unregister_cpu(c); > -} > -EXPORT_SYMBOL(arch_unregister_cpu); > #endif