From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753608Ab3F0Nyw (ORCPT ); Thu, 27 Jun 2013 09:54:52 -0400 Received: from smtp.citrix.com ([66.165.176.89]:9674 "EHLO SMTP.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753567Ab3F0Nyu (ORCPT ); Thu, 27 Jun 2013 09:54:50 -0400 X-IronPort-AV: E=Sophos;i="4.87,952,1363132800"; d="scan'208";a="33808354" From: Stefano Stabellini To: CC: , , , , , , , , , , , Stefano Stabellini , , , Subject: [PATCH v6 4/5] arm64: introduce CONFIG_PARAVIRT, PARAVIRT_TIME_ACCOUNTING and pv_time_ops Date: Thu, 27 Jun 2013 14:54:31 +0100 Message-ID: <1372341272-12512-4-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 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- arch/arm64/Kconfig | 20 ++++++++++++++++++++ arch/arm64/include/asm/paravirt.h | 19 +++++++++++++++++++ arch/arm64/kernel/Makefile | 1 + arch/arm64/kernel/paravirt.c | 25 +++++++++++++++++++++++++ 4 files changed, 65 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..54e895b --- /dev/null +++ b/arch/arm64/include/asm/paravirt.h @@ -0,0 +1,19 @@ +#ifndef _ASM_ARM64_PARAVIRT_H +#define _ASM_ARM64_PARAVIRT_H + +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 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); -- 1.7.2.5