From patchwork Wed Jan 8 18:49:55 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefano Stabellini X-Patchwork-Id: 3455551 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 CCB349F374 for ; Wed, 8 Jan 2014 18:53:57 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id BDF6B2010C for ; Wed, 8 Jan 2014 18:53:56 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 94C7220103 for ; Wed, 8 Jan 2014 18:53:55 +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 1W0yEh-0002dS-N5; Wed, 08 Jan 2014 18:52:16 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1W0yEJ-0006TS-Pm; Wed, 08 Jan 2014 18:51:51 +0000 Received: from smtp02.citrix.com ([66.165.176.63]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1W0yDm-0006O1-Db for linux-arm-kernel@lists.infradead.org; Wed, 08 Jan 2014 18:51:23 +0000 X-IronPort-AV: E=Sophos;i="4.95,625,1384300800"; d="scan'208";a="88846947" Received: from accessns.citrite.net (HELO FTLPEX01CL01.citrite.net) ([10.9.154.239]) by FTLPIPO02.CITRIX.COM with ESMTP; 08 Jan 2014 18:50:56 +0000 Received: from ukmail1.uk.xensource.com (10.80.16.128) by smtprelay.citrix.com (10.13.107.78) with Microsoft SMTP Server id 14.2.342.4; Wed, 8 Jan 2014 13:50:56 -0500 Received: from kaball.uk.xensource.com ([10.80.2.59]) by ukmail1.uk.xensource.com with esmtp (Exim 4.69) (envelope-from ) id 1W0yDL-0005sr-54; Wed, 08 Jan 2014 18:50:51 +0000 From: Stefano Stabellini To: Subject: [PATCH v8 3/6] arm: introduce CONFIG_PARAVIRT, PARAVIRT_TIME_ACCOUNTING and pv_time_ops Date: Wed, 8 Jan 2014 18:49:55 +0000 Message-ID: <1389206998-27875-3-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-DLP: MIA1 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140108_135118_699094_935649D9 X-CRM114-Status: GOOD ( 10.14 ) X-Spam-Score: -2.7 (--) 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=-4.3 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 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 Acked-by: Christopher Covington CC: linux@arm.linux.org.uk 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 Acked-by: Ian Campbell --- Changes in v7: - ifdef CONFIG_PARAVIRT the content of paravirt.h. Changes in v3: - improve commit description and Kconfig help text; - no need to initialize pv_time_ops; - add PARAVIRT_TIME_ACCOUNTING. --- arch/arm/Kconfig | 20 ++++++++++++++++++++ arch/arm/kernel/Makefile | 1 + 2 files changed, 21 insertions(+) diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index c1f1a7e..d6c3ba1 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1874,6 +1874,25 @@ config SWIOTLB config IOMMU_HELPER def_bool SWIOTLB +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 @@ -1885,6 +1904,7 @@ config XEN depends on !GENERIC_ATOMIC64 select ARM_PSCI select SWIOTLB_XEN + select PARAVIRT help Say Y if you want to run Linux in a Virtual Machine on Xen on ARM. diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index a30fc9b..bcd2b38 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -87,6 +87,7 @@ obj-$(CONFIG_ARM_CPU_TOPOLOGY) += topology.o ifneq ($(CONFIG_ARCH_EBSA110),y) obj-y += io.o endif +obj-$(CONFIG_PARAVIRT) += paravirt.o head-y := head$(MMUEXT).o obj-$(CONFIG_DEBUG_LL) += debug.o