On Wed, 2014-01-08 at 18:49 +0000, Stefano Stabellini wrote: > 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 <[email protected]> > Acked-by: Christopher Covington <[email protected]>
Acked-by: Ian Campbell <[email protected]> > CC: [email protected] > CC: [email protected] > CC: [email protected] > CC: [email protected] > CC: [email protected] > CC: [email protected] > CC: [email protected] > > --- > > 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 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
