From patchwork Fri Dec 6 10:17:26 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jinjie Ruan X-Patchwork-Id: 13896829 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 lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 984E6E77182 for ; Fri, 6 Dec 2024 10:18:29 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.849982.1264451 (Exim 4.92) (envelope-from ) id 1tJVPd-00023Q-TP; Fri, 06 Dec 2024 10:18:17 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 849982.1264451; Fri, 06 Dec 2024 10:18:17 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1tJVPd-00023J-Qk; Fri, 06 Dec 2024 10:18:17 +0000 Received: by outflank-mailman (input) for mailman id 849982; Fri, 06 Dec 2024 10:18:16 +0000 Received: from se1-gles-sth1-in.inumbo.com ([159.253.27.254] helo=se1-gles-sth1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1tJVPc-0001of-PX for xen-devel@lists.xenproject.org; Fri, 06 Dec 2024 10:18:16 +0000 Received: from szxga07-in.huawei.com (szxga07-in.huawei.com [45.249.212.35]) by se1-gles-sth1.inumbo.com (Halon) with ESMTPS id 66547a32-b3bb-11ef-a0d5-8be0dac302b0; Fri, 06 Dec 2024 11:18:15 +0100 (CET) Received: from mail.maildlp.com (unknown [172.19.162.112]) by szxga07-in.huawei.com (SkyGuard) with ESMTP id 4Y4Rwm0C8Qz1T4md; Fri, 6 Dec 2024 18:15:52 +0800 (CST) Received: from kwepemg200008.china.huawei.com (unknown [7.202.181.35]) by mail.maildlp.com (Postfix) with ESMTPS id EF8031401DC; Fri, 6 Dec 2024 18:18:11 +0800 (CST) Received: from huawei.com (10.90.53.73) 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; Fri, 6 Dec 2024 18:18:10 +0800 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 66547a32-b3bb-11ef-a0d5-8be0dac302b0 From: Jinjie Ruan To: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , Subject: [PATCH -next v5 04/22] arm64: entry: Rework arm64_preempt_schedule_irq() Date: Fri, 6 Dec 2024 18:17:26 +0800 Message-ID: <20241206101744.4161990-5-ruanjinjie@huawei.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20241206101744.4161990-1-ruanjinjie@huawei.com> References: <20241206101744.4161990-1-ruanjinjie@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.90.53.73] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To kwepemg200008.china.huawei.com (7.202.181.35) The generic entry do preempt_schedule_irq() by checking if need_resched() satisfied, but arm64 has some of its own additional checks such as GIC priority masking. In preparation for moving arm64 over to the generic entry code, rework arm64_preempt_schedule_irq() to check whether it need resched in a check function called arm64_need_resched(). No functional changes. Signed-off-by: Jinjie Ruan --- arch/arm64/kernel/entry-common.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) diff --git a/arch/arm64/kernel/entry-common.c b/arch/arm64/kernel/entry-common.c index 7a588515ee07..da68c089b74b 100644 --- a/arch/arm64/kernel/entry-common.c +++ b/arch/arm64/kernel/entry-common.c @@ -83,10 +83,10 @@ DEFINE_STATIC_KEY_TRUE(sk_dynamic_irqentry_exit_cond_resched); #define need_irq_preemption() (IS_ENABLED(CONFIG_PREEMPTION)) #endif -static void __sched arm64_preempt_schedule_irq(void) +static inline bool arm64_need_resched(void) { if (!need_irq_preemption()) - return; + return false; /* * Note: thread_info::preempt_count includes both thread_info::count @@ -94,7 +94,7 @@ static void __sched arm64_preempt_schedule_irq(void) * preempt_count(). */ if (READ_ONCE(current_thread_info()->preempt_count) != 0) - return; + return false; /* * DAIF.DA are cleared at the start of IRQ/FIQ handling, and when GIC @@ -103,7 +103,7 @@ static void __sched arm64_preempt_schedule_irq(void) * DAIF we must have handled an NMI, so skip preemption. */ if (system_uses_irq_prio_masking() && read_sysreg(daif)) - return; + return false; /* * Preempting a task from an IRQ means we leave copies of PSTATE @@ -113,8 +113,10 @@ static void __sched arm64_preempt_schedule_irq(void) * Only allow a task to be preempted once cpufeatures have been * enabled. */ - if (system_capabilities_finalized()) - preempt_schedule_irq(); + if (!system_capabilities_finalized()) + return false; + + return true; } /* @@ -139,7 +141,8 @@ static __always_inline void __exit_to_kernel_mode(struct pt_regs *regs, return; } - arm64_preempt_schedule_irq(); + if (arm64_need_resched()) + preempt_schedule_irq(); trace_hardirqs_on(); } else {