From patchwork Fri Jun 28 11:20:45 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefano Stabellini X-Patchwork-Id: 2798401 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 1A1929F245 for ; Fri, 28 Jun 2013 11:25:47 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1F257201D3 for ; Fri, 28 Jun 2013 11:25:46 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 277AB200E0 for ; Fri, 28 Jun 2013 11:25:44 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1UsWlb-0005v2-HI; Fri, 28 Jun 2013 11:23:05 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1UsWkg-00028d-TU; Fri, 28 Jun 2013 11:22:06 +0000 Received: from smtp.citrix.com ([66.165.176.89]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1UsWkA-00024F-Ny for linux-arm-kernel@lists.infradead.org; Fri, 28 Jun 2013 11:21:39 +0000 X-IronPort-AV: E=Sophos;i="4.87,958,1363132800"; d="scan'208";a="34056485" Received: from accessns.citrite.net (HELO FTLPEX01CL02.citrite.net) ([10.9.154.239]) by FTLPIPO01.CITRIX.COM with ESMTP/TLS/AES128-SHA; 28 Jun 2013 11:21:05 +0000 Received: from ukmail1.uk.xensource.com (10.80.16.128) by smtprelay.citrix.com (10.13.107.79) with Microsoft SMTP Server id 14.2.342.4; Fri, 28 Jun 2013 07:21:04 -0400 Received: from kaball.uk.xensource.com ([10.80.2.59]) by ukmail1.uk.xensource.com with esmtp (Exim 4.69) (envelope-from ) id 1UsWjW-00088a-Ec; Fri, 28 Jun 2013 12:20:54 +0100 From: Stefano Stabellini To: Subject: [PATCH v7 4/6] arm64: introduce CONFIG_PARAVIRT, PARAVIRT_TIME_ACCOUNTING and pv_time_ops Date: Fri, 28 Jun 2013 12:20:45 +0100 Message-ID: <1372418447-24066-4-git-send-email-stefano.stabellini@eu.citrix.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: References: MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130628_072135_032672_B81B945B X-CRM114-Status: GOOD ( 15.24 ) X-Spam-Score: -8.2 (--------) Cc: linux@arm.linux.org.uk, Ian.Campbell@citrix.com, arnd@arndb.de, Stefano Stabellini , marc.zyngier@arm.com, Catalin.Marinas@arm.com, konrad.wilk@oracle.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, nico@linaro.org, olof@lixom.net, linux-arm-kernel@lists.infradead.org, cov@codeaurora.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-5.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Introduce CONFIG_PARAVIRT and PARAVIRT_TIME_ACCOUNTING on ARM64. Necessary duplication of paravirt.h and paravirt.c with ARM. The only paravirt interface supported is pv_time_ops.steal_clock, so no runtime pvops patching needed. This allows us to make use of steal_account_process_tick for stolen ticks accounting. Signed-off-by: Stefano Stabellini CC: will.deacon@arm.com CC: nico@linaro.org CC: marc.zyngier@arm.com CC: cov@codeaurora.org CC: arnd@arndb.de CC: olof@lixom.net CC: Catalin.Marinas@arm.com --- Changes in v7: - ifdef CONFIG_PARAVIRT the content of paravirt.h. --- arch/arm64/Kconfig | 20 ++++++++++++++++++++ arch/arm64/include/asm/paravirt.h | 20 ++++++++++++++++++++ arch/arm64/kernel/Makefile | 1 + arch/arm64/kernel/paravirt.c | 25 +++++++++++++++++++++++++ 4 files changed, 66 insertions(+), 0 deletions(-) create mode 100644 arch/arm64/include/asm/paravirt.h create mode 100644 arch/arm64/kernel/paravirt.c diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 1fac4e5..4c4f213 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -190,6 +190,25 @@ config HW_PERF_EVENTS source "mm/Kconfig" +config PARAVIRT + bool "Enable paravirtualization code" + ---help--- + This changes the kernel so it can modify itself when it is run + under a hypervisor, potentially improving performance significantly + over full virtualization. + +config PARAVIRT_TIME_ACCOUNTING + bool "Paravirtual steal time accounting" + select PARAVIRT + default n + ---help--- + Select this option to enable fine granularity task steal time + accounting. Time spent executing other tasks in parallel with + the current vCPU is discounted from the vCPU power. To account for + that, there can be a small performance impact. + + If in doubt, say N here. + config XEN_DOM0 def_bool y depends on XEN @@ -197,6 +216,7 @@ config XEN_DOM0 config XEN bool "Xen guest support on ARM64 (EXPERIMENTAL)" depends on ARM64 && OF + select PARAVIRT help Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64. diff --git a/arch/arm64/include/asm/paravirt.h b/arch/arm64/include/asm/paravirt.h new file mode 100644 index 0000000..fd5f428 --- /dev/null +++ b/arch/arm64/include/asm/paravirt.h @@ -0,0 +1,20 @@ +#ifndef _ASM_ARM64_PARAVIRT_H +#define _ASM_ARM64_PARAVIRT_H + +#ifdef CONFIG_PARAVIRT +struct static_key; +extern struct static_key paravirt_steal_enabled; +extern struct static_key paravirt_steal_rq_enabled; + +struct pv_time_ops { + unsigned long long (*steal_clock)(int cpu); +}; +extern struct pv_time_ops pv_time_ops; + +static inline u64 paravirt_steal_clock(int cpu) +{ + return pv_time_ops.steal_clock(cpu); +} +#endif + +#endif diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index 7b4b564..17613ad 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -18,6 +18,7 @@ arm64-obj-$(CONFIG_SMP) += smp.o smp_spin_table.o smp_psci.o arm64-obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o arm64-obj-$(CONFIG_HAVE_HW_BREAKPOINT)+= hw_breakpoint.o arm64-obj-$(CONFIG_EARLY_PRINTK) += early_printk.o +arm64-obj-$(CONFIG_PARAVIRT) += paravirt.o obj-y += $(arm64-obj-y) vdso/ obj-m += $(arm64-obj-m) diff --git a/arch/arm64/kernel/paravirt.c b/arch/arm64/kernel/paravirt.c new file mode 100644 index 0000000..53f371e --- /dev/null +++ b/arch/arm64/kernel/paravirt.c @@ -0,0 +1,25 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * Copyright (C) 2013 Citrix Systems + * + * Author: Stefano Stabellini + */ + +#include +#include +#include +#include + +struct static_key paravirt_steal_enabled; +struct static_key paravirt_steal_rq_enabled; + +struct pv_time_ops pv_time_ops; +EXPORT_SYMBOL_GPL(pv_time_ops);