| Message ID | 1389292336-9292-4-git-send-email-stefano.stabellini@eu.citrix.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Jan 09, 2014 at 06:32:15PM +0000, Stefano Stabellini wrote: > 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 <stefano.stabellini@eu.citrix.com> > 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 Acked-by: Catalin Marinas <catalin.marinas@arm.com>
On Thu, 9 Jan 2014, Stefano Stabellini wrote: > 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 <stefano.stabellini@eu.citrix.com> > 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 Catalin, Will, are you happy with this patch for 3.15? > 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(+) > 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 6d4dd22..d1003ba 100644 > --- a/arch/arm64/Kconfig > +++ b/arch/arm64/Kconfig > @@ -212,6 +212,25 @@ config HAVE_ARCH_TRANSPARENT_HUGEPAGE > > 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 > @@ -220,6 +239,7 @@ config XEN > bool "Xen guest support on ARM64 (EXPERIMENTAL)" > depends on ARM64 && OF > select SWIOTLB_XEN > + 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 5ba2fd4..1dee735 100644 > --- a/arch/arm64/kernel/Makefile > +++ b/arch/arm64/kernel/Makefile > @@ -18,6 +18,7 @@ arm64-obj-$(CONFIG_SMP) += smp.o smp_spin_table.o > arm64-obj-$(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 <stefano.stabellini@eu.citrix.com> > + */ > + > +#include <linux/export.h> > +#include <linux/jump_label.h> > +#include <linux/types.h> > +#include <asm/paravirt.h> > + > +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); > -- > 1.7.10.4 >
On Mon, Feb 17, 2014 at 12:25:42PM +0000, Stefano Stabellini wrote: > On Thu, 9 Jan 2014, Stefano Stabellini wrote: > > 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 <stefano.stabellini@eu.citrix.com> > > 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 > > Catalin, Will, are you happy with this patch for 3.15? It's pretty small and looks fine to me. However, I would like someone with more virtualisation experience than me to ack it (e.g. Marc Z). Some nitpicks: > > +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--- For consistency with this file, just use "help" rather than "---help---". > > --- /dev/null > > +++ b/arch/arm64/include/asm/paravirt.h > > @@ -0,0 +1,20 @@ > > +#ifndef _ASM_ARM64_PARAVIRT_H > > +#define _ASM_ARM64_PARAVIRT_H __ASM_PARAVIRT_H for consistency.
On Mon, 17 Feb 2014, Catalin Marinas wrote: > On Mon, Feb 17, 2014 at 12:25:42PM +0000, Stefano Stabellini wrote: > > On Thu, 9 Jan 2014, Stefano Stabellini wrote: > > > 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 <stefano.stabellini@eu.citrix.com> > > > 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 > > > > Catalin, Will, are you happy with this patch for 3.15? > > It's pretty small and looks fine to me. However, I would like someone > with more virtualisation experience than me to ack it (e.g. Marc Z). Ping? Marc, could you please give it a review? > Some nitpicks: > > > > +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--- > > For consistency with this file, just use "help" rather than > "---help---". > > > > --- /dev/null > > > +++ b/arch/arm64/include/asm/paravirt.h > > > @@ -0,0 +1,20 @@ > > > +#ifndef _ASM_ARM64_PARAVIRT_H > > > +#define _ASM_ARM64_PARAVIRT_H > > __ASM_PARAVIRT_H for consistency. > > -- > Catalin >
On 25/03/14 11:19, Stefano Stabellini wrote: > On Mon, 17 Feb 2014, Catalin Marinas wrote: >> On Mon, Feb 17, 2014 at 12:25:42PM +0000, Stefano Stabellini wrote: >>> On Thu, 9 Jan 2014, Stefano Stabellini wrote: >>>> 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 <stefano.stabellini@eu.citrix.com> >>>> 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 >>> >>> Catalin, Will, are you happy with this patch for 3.15? >> >> It's pretty small and looks fine to me. However, I would like someone >> with more virtualisation experience than me to ack it (e.g. Marc Z). > > Ping? Marc, could you please give it a review? Yup, that looks OK to me. It's a generic feature anyway, so I don't see any harm in enabling it for Xen. We may also use it for KVM at some point. Acked-by: Marc Zyngier <marc.zyngier@arm.com> M.
On Tue, 25 Mar 2014, Marc Zyngier wrote: > On 25/03/14 11:19, Stefano Stabellini wrote: > > On Mon, 17 Feb 2014, Catalin Marinas wrote: > >> On Mon, Feb 17, 2014 at 12:25:42PM +0000, Stefano Stabellini wrote: > >>> On Thu, 9 Jan 2014, Stefano Stabellini wrote: > >>>> 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 <stefano.stabellini@eu.citrix.com> > >>>> 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 > >>> > >>> Catalin, Will, are you happy with this patch for 3.15? > >> > >> It's pretty small and looks fine to me. However, I would like someone > >> with more virtualisation experience than me to ack it (e.g. Marc Z). > > > > Ping? Marc, could you please give it a review? > > Yup, that looks OK to me. It's a generic feature anyway, so I don't see > any harm in enabling it for Xen. We may also use it for KVM at some point. > > Acked-by: Marc Zyngier <marc.zyngier@arm.com> Thanks!
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 6d4dd22..d1003ba 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -212,6 +212,25 @@ config HAVE_ARCH_TRANSPARENT_HUGEPAGE 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 @@ -220,6 +239,7 @@ config XEN bool "Xen guest support on ARM64 (EXPERIMENTAL)" depends on ARM64 && OF select SWIOTLB_XEN + 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 5ba2fd4..1dee735 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 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 <stefano.stabellini@eu.citrix.com> + */ + +#include <linux/export.h> +#include <linux/jump_label.h> +#include <linux/types.h> +#include <asm/paravirt.h> + +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);
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 <stefano.stabellini@eu.citrix.com> 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(+) create mode 100644 arch/arm64/include/asm/paravirt.h create mode 100644 arch/arm64/kernel/paravirt.c