From patchwork Wed Feb 26 00:23:51 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gavin Shan X-Patchwork-Id: 11405045 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 4CBEF930 for ; Wed, 26 Feb 2020 00:24:15 +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 14A5C21927 for ; Wed, 26 Feb 2020 00:24:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="EpTmTwJT"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="RtKDtPCn" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 14A5C21927 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.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:MIME-Version:Message-Id:Date:Subject:To :From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=sMytA7RXKCi6iF+o84AFnjSvdLDPtmK/uUQLDM4Px/E=; b=EpTmTwJTqWwS8b To7r/sW73EUfjNHFUPoySGStSISyzKOgqGvl6XWK3nCvv560d283peV1CROJuiR07pY+OkW7/MDGR 9Ev1lonRyYHzdaqB2iknLOo9sLxqn5Iz/RdY0N3DvjqpNYHsdgF9FNkM63Tq3VMin6ZZh2nQBO7kh 7VrtC7CjDiORfvxrpq0Yf0ieGRjx94XTNrCwcXwJOCBkOuZ3vFH64/5uH2LSZ8Xt/NY8VxZvOYjHy uLf4uPXvr+p7fWS9KMiX/n+RwuC/TCAEILlhMrh1OGgaLhv7GMkRbHF0mqb4JgKHk56SwcRkUXP19 7Vh1X4q8NcCZQ4o1ovYg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1j6kUo-00017S-LW; Wed, 26 Feb 2020 00:24:14 +0000 Received: from us-smtp-2.mimecast.com ([207.211.31.81] helo=us-smtp-delivery-1.mimecast.com) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1j6kUl-00016v-Oq for linux-arm-kernel@lists.infradead.org; Wed, 26 Feb 2020 00:24:13 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1582676650; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=xvRnwcA6y9Q6vt+IdJWl13EK/sQzHk/6x0Ri/upM/Nw=; b=RtKDtPCn5JmtjeNXctmw2eZNXqA+v1Mi312hEFuAWucqLKG9XPxXQvDn+xYrEp3OKRcd5Q dlsBSXXRjXLmx/6UjsPCyBi3xkgu+kFqxhySgJD9Tln8VuqrvajOZKy5S0gOnJzFF+Gyx/ Y2P3t6zeqcSVDg5OYKPXEWeMQ6JP3sw= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-293-C9CrSTxXNBut2u7DYP2a2Q-1; Tue, 25 Feb 2020 19:24:06 -0500 X-MC-Unique: C9CrSTxXNBut2u7DYP2a2Q-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D1970107ACC9; Wed, 26 Feb 2020 00:24:04 +0000 (UTC) Received: from localhost.localdomain.com (vpn2-54-83.bne.redhat.com [10.64.54.83]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0DE885C21B; Wed, 26 Feb 2020 00:24:01 +0000 (UTC) From: Gavin Shan To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v4 0/5] arm64: Dereference CPU operations indirectly Date: Wed, 26 Feb 2020 11:23:51 +1100 Message-Id: <20200226002356.86986-1-gshan@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200225_162411_884243_28F19867 X-CRM114-Status: UNSURE ( 9.66 ) X-CRM114-Notice: Please train this message. X-Spam-Score: -0.2 (/) X-Spam-Report: SpamAssassin version 3.4.3 on bombadil.infradead.org summary: Content analysis details: (-0.2 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at https://www.dnswl.org/, no trust [207.211.31.81 listed in list.dnswl.org] 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.0 SPF_PASS SPF: sender matches SPF record 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature -0.0 DKIMWL_WL_HIGH DKIMwl.org - Whitelisted High sender 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: mark.rutland@arm.com, lorenzo.pieralisi@arm.com, catalin.marinas@arm.com, robin.murphy@arm.com, shan.gavin@gmail.com, sudeep.holla@arm.com, will@kernel.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org The subject perhaps can't precisely indicate what this series does, but keep it same as before for consistency. In current implementation, an array (@cpu_ops[NR_CPUS]) is maintained to dereference the CPU operations. 2KB memory are consumed when NR_CPUS is configured to 256. It's too much than what I expected. This series reworks the implementation to dereference the CPU operations by using a CPU operations pointer with assumption - all CPUs should have unified CPU operations. With this, 8-bytes memory will be used for same purpose. PATCH[1/5] isn't too much relevant, to declare ACPI parking protocol only when CONFIG_ARM64_ACPI_PARKING_PROTOCOL has been enabled. PATCH[2/5] renames cpu_read_ops() to init_cpu_ops(), which is obviously more precise because it's initializing the CPU operations. PATCH[3/5] introduces get_cpu_ops(), preparing for droping the array of CPU operations. PATCH[4/5] removes the CPU operations deferencing array and replaces it with a pointer with the assumption: all CPUs should have same enablement method. PATCH[5/5] removes the cpu argument of get_cpu_ops() as it's not used any more. Changelog ========= v4: * Rebase to 5.6.rc3 and retest (Gavin Shan) * Improved commit log for PATCH[4/5] with link tag (Lorenzo Pieralisi) * Using pointer instead of index to dereference the unified CPU operations (Lorenzo Pieralisi) * Merge logic of cpu_get_ops() to get_cpu_method() (Gavin Shan) v3: * Assume all CPUs have same enablement method. With this, the used memory is further squeezed from 64 bytes to 4 bytes (Lorenzo Pieralisi) * Add PATCH[5/5] to remove argument of get_cpu_ops() (Gavin Shan) v2: * Pack 4 CPUs' indexes into one byte. 64 bytes are consumed in order to get the CPU operations (Robin Murphy) * Use ARRAY_SIZE() to iterate @cpu_ops[] (Robin Murphy) * Make index-0 valid (Robin Murphy) Gavin Shan (5): arm64: Declare ACPI parking protocol CPU operation if needed arm64: Rename cpu_read_ops() to init_cpu_ops() arm64: Introduce get_cpu_ops() helper function arm64: Remove CPU operations dereferencing array arm64: Remove argument @cpu of get_cpu_ops() arch/arm64/include/asm/cpu_ops.h | 8 ++-- arch/arm64/kernel/cpu_ops.c | 77 ++++++++++++++++---------------- arch/arm64/kernel/cpuidle.c | 10 ++--- arch/arm64/kernel/setup.c | 8 ++-- arch/arm64/kernel/smp.c | 60 ++++++++++++++++--------- 5 files changed, 93 insertions(+), 70 deletions(-)