From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) (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 00271EEC5 for ; Tue, 29 Oct 2024 02:34:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.188 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730169247; cv=none; b=pWlCM9+3gOfmPlKfH4u9qC7bb5Ql21jxXMhpITC9dB3a9v4Tk83H5CLsDL9OKxGg+x/+8apdwoJbNCvsmIBUI7V25RoR8UgQLKyPcMnL1Ei7WjfMKdJKusuZahc0iaEKQnLVTxrFnMj9HxzwlWOJNZ42igO0GxA2h/pRI56Hc4A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730169247; c=relaxed/simple; bh=VABOPakHa2apOv7zAxD6bUx1YB8Vlh4yW1SEAIF35Bw=; h=Message-ID:Date:MIME-Version:Subject:To:References:From: In-Reply-To:Content-Type; b=RULttwo0M3un3Bk7MuHgq0FA44N8d54ITNeVkY8xHKhG2JaGN6t+CbnXjaSJDg4O0QDLCTmLmsc8JPXAwZPTWdI9NIxoPzQdA5iRc+AAinng7PBf+rZyA/cwDWCRJJ/r/F2lljtPcvcLG1MOQBgVsTXcMtmzIxcoeIb2ougT6Oc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.188 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.163.48]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4XcvQQ6V28zfdZx; Tue, 29 Oct 2024 10:31:26 +0800 (CST) Received: from kwepemg200008.china.huawei.com (unknown [7.202.181.35]) by mail.maildlp.com (Postfix) with ESMTPS id D8120180064; Tue, 29 Oct 2024 10:33:59 +0800 (CST) Received: from [10.67.109.254] (10.67.109.254) by kwepemg200008.china.huawei.com (7.202.181.35) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Tue, 29 Oct 2024 10:33:57 +0800 Message-ID: <264f092c-dbaa-b475-831f-f50f4471de2f@huawei.com> Date: Tue, 29 Oct 2024 10:33:56 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.2.0 Subject: Re: [PATCH -next v4 15/19] entry: Add arch irqentry_exit_need_resched() for arm64 Content-Language: en-US To: Thomas Gleixner , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , References: <20241025100700.3714552-1-ruanjinjie@huawei.com> <20241025100700.3714552-16-ruanjinjie@huawei.com> <878qu82je2.ffs@tglx> From: Jinjie Ruan In-Reply-To: <878qu82je2.ffs@tglx> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To kwepemg200008.china.huawei.com (7.202.181.35) On 2024/10/29 2:05, Thomas Gleixner wrote: > On Fri, Oct 25 2024 at 18:06, Jinjie Ruan wrote: > >> As the front patch 6 ~ 13 did, the arm64_preempt_schedule_irq() is > > Once this series is applied nobody knows what 'front patch 6 ~ 13' did. Yes, if some of the previous patches are applied, the description will immediately become difficult to understand, the other patch's similar commit message will be updated too. > >> same with the irq preempt schedule code of generic entry besides those >> architecture-related logic called arm64_irqentry_exit_need_resched(). >> >> So add arch irqentry_exit_need_resched() to support architecture-related >> need_resched() check logic, which do not affect existing architectures >> that use generic entry, but support arm64 to use generic irq entry. > > Simply say: > > ARM64 requires an additional whether to reschedule on return from > interrupt. > > Add arch_irqentry_exit_need_resched() as the default NOOP > implementation and hook it up into the need_resched() condition in > raw_irqentry_exit_cond_resched(). > > This allows ARM64 to implement the architecture specific version for > switchting over to the generic entry code. > > That explains things completely independently. Hmm? Of course, this is clearer and not as coupled as other patches and describes how to implement it. > > Thanks, > > tglx >