From patchwork Wed Oct 9 04:45:16 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yunfeng Ye X-Patchwork-Id: 11180495 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 631EB112B for ; Wed, 9 Oct 2019 04:46:02 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 40A1C21835 for ; Wed, 9 Oct 2019 04:46:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="MWCpdJr/" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 40A1C21835 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date: Message-ID:References:To:From:Subject:Reply-To:Content-ID:Content-Description :Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=/GDPwMvuThx9jq0ELPAagT5FnZLswhmqXZyl97+yhOs=; b=MWCpdJr/FR+xU+ nbCe6IKbluIl3UeIKkeopJPgnInOcqdUQILia1Bm27RZeSfunLK/8Ex3VjVRrPRqjNofhIHsIhv+u 1uQJMGnr9IQZ5zUdHXJVvVNv77q5D/2f5m2QW1IbEmoEDzO9HlsPG+7mftMAYI3g+ntqIy9mAgUdm 1olXp/MjwJy7xYTtnUIAE3zK5Vv+VHqwcXNV4FHHRZ//zIMJbe3OAK1yyn+hXNHo8wtaCnPu3mKIL 8eayGtNkepZVT6Srv/O//uhZMxS+T1LuHZZq/o/WdFAil5vRPqmolaG0bps1AxrrYPFvf4DGUCMn5 n/qckSq6QXyDRwzA3O1g==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.2 #3 (Red Hat Linux)) id 1iI3rM-0003MN-CY; Wed, 09 Oct 2019 04:46:00 +0000 Received: from szxga05-in.huawei.com ([45.249.212.191] helo=huawei.com) by bombadil.infradead.org with esmtps (Exim 4.92.2 #3 (Red Hat Linux)) id 1iI3rJ-0003Lm-4j for linux-arm-kernel@lists.infradead.org; Wed, 09 Oct 2019 04:45:58 +0000 Received: from DGGEMS403-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 536C27FB91AF7942FE52; Wed, 9 Oct 2019 12:45:51 +0800 (CST) Received: from [127.0.0.1] (10.177.251.225) by DGGEMS403-HUB.china.huawei.com (10.3.19.203) with Microsoft SMTP Server id 14.3.439.0; Wed, 9 Oct 2019 12:45:44 +0800 Subject: [PATCH V2] arm64: psci: Reduce waiting time of cpu_psci_cpu_kill() From: Yunfeng Ye To: David Laight , "catalin.marinas@arm.com" , "will@kernel.org" , "kstewart@linuxfoundation.org" , "gregkh@linuxfoundation.org" , "ard.biesheuvel@linaro.org" , "tglx@linutronix.de" References: <18068756-0f39-6388-3290-cf03746e767d@huawei.com> Message-ID: <9df267db-e647-a81d-16bb-b8bfb06c2624@huawei.com> Date: Wed, 9 Oct 2019 12:45:16 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <18068756-0f39-6388-3290-cf03746e767d@huawei.com> Content-Language: en-US X-Originating-IP: [10.177.251.225] X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191008_214557_358680_8469799E X-CRM114-Status: GOOD ( 14.40 ) X-Spam-Score: -2.3 (--) X-Spam-Report: SpamAssassin version 3.4.2 on bombadil.infradead.org summary: Content analysis details: (-2.3 points) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at https://www.dnswl.org/, medium trust [45.249.212.191 listed in list.dnswl.org] -0.0 SPF_HELO_PASS SPF: HELO matches SPF record -0.0 SPF_PASS SPF: sender matches SPF record X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "wuyun.wu@huawei.com" , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org If psci_ops.affinity_info() fails, it will sleep 10ms, which will not take so long in the right case. Use usleep_range() instead of msleep(), reduce the waiting time, and give a chance to busy wait before sleep. Signed-off-by: Yunfeng Ye --- V1->V2: - use usleep_range() instead of udelay() after waiting for a while arch/arm64/kernel/psci.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c index c9f72b2..99b3122 100644 --- a/arch/arm64/kernel/psci.c +++ b/arch/arm64/kernel/psci.c @@ -82,6 +82,7 @@ static void cpu_psci_cpu_die(unsigned int cpu) static int cpu_psci_cpu_kill(unsigned int cpu) { int err, i; + unsigned long timeout; if (!psci_ops.affinity_info) return 0; @@ -91,16 +92,24 @@ static int cpu_psci_cpu_kill(unsigned int cpu) * while it is dying. So, try again a few times. */ - for (i = 0; i < 10; i++) { + i = 0; + timeout = jiffies + msecs_to_jiffies(100); + do { err = psci_ops.affinity_info(cpu_logical_map(cpu), 0); if (err == PSCI_0_2_AFFINITY_LEVEL_OFF) { pr_info("CPU%d killed.\n", cpu); return 0; } - msleep(10); - pr_info("Retrying again to check for CPU kill\n"); - } + /* busy-wait max 1ms */ + if (i++ < 100) { + cond_resched(); + udelay(10); + continue; + } + + usleep_range(100, 1000); + } while (time_before(jiffies, timeout)); pr_warn("CPU%d may not have shut down cleanly (AFFINITY_INFO reports %d)\n", cpu, err);