On Mon, 11 Jun 2018 11:18:56 -0400
nilal@xxxxxxxxxx wrote:
> From: Nitesh Narayan Lal <nilal@xxxxxxxxxx>
>
> This patch includes the following:
> 1. Basic skeleton for the support
> 2. Enablement of x86 platform to use the same
>
> Signed-off-by: Nitesh Narayan Lal <nilal@xxxxxxxxxx>
> ---
> arch/x86/Kbuild | 2 +-
> arch/x86/kvm/Kconfig | 6 ++++++
> arch/x86/kvm/Makefile | 2 ++
> include/linux/gfp.h | 7 +++++++
> 4 files changed, 16 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/Kbuild b/arch/x86/Kbuild
> index 0038a2d..7d39d7d 100644
> --- a/arch/x86/Kbuild
> +++ b/arch/x86/Kbuild
> @@ -2,7 +2,7 @@ obj-y += entry/
>
> obj-$(CONFIG_PERF_EVENTS) += events/
>
> -obj-$(CONFIG_KVM) += kvm/
> +obj-$(subst m,y,$(CONFIG_KVM)) += kvm/
>
> # Xen paravirtualization support
> obj-$(CONFIG_XEN) += xen/
> diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
> index 92fd433..e8b1291 100644
> --- a/arch/x86/kvm/Kconfig
> +++ b/arch/x86/kvm/Kconfig
> @@ -96,6 +96,12 @@ config KVM_MMU_AUDIT
> This option adds a R/W kVM module parameter 'mmu_audit', which allows
> auditing of KVM MMU events at runtime.
>
> +config KVM_FREE_PAGE_HINTING
> + def_bool y
> + depends on KVM
> + select VIRTIO
> + select VIRTIO_BALLOON
I think it's a good practice to write the help text explaining what
the feature does and when to disable it.
> +
> # OK, it's a little counter-intuitive to do this, but it puts it neatly under
> # the virtualization menu.
> source drivers/vhost/Kconfig
> diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
> index dc4f2fd..866dd56 100644
> --- a/arch/x86/kvm/Makefile
> +++ b/arch/x86/kvm/Makefile
> @@ -16,6 +16,8 @@ kvm-y += x86.o mmu.o emulate.o i8259.o irq.o lapic.o \
> i8254.o ioapic.o irq_comm.o cpuid.o pmu.o mtrr.o \
> hyperv.o page_track.o debugfs.o
>
> +obj-$(CONFIG_KVM_FREE_PAGE_HINTING) += $(KVM)/page_hinting.o
> +
> kvm-intel-y += vmx.o pmu_intel.o
> kvm-amd-y += svm.o pmu_amd.o
>
> diff --git a/include/linux/gfp.h b/include/linux/gfp.h
> index a6afcec..72cd41b 100644
> --- a/include/linux/gfp.h
> +++ b/include/linux/gfp.h
> @@ -439,6 +439,13 @@ static inline struct zonelist *node_zonelist(int nid, gfp_t flags)
> return NODE_DATA(nid)->node_zonelists + gfp_zonelist(flags);
> }
>
> +#ifdef CONFIG_KVM_FREE_PAGE_HINTING
> +#define HAVE_ARCH_ALLOC_PAGE
> +#define HAVE_ARCH_FREE_PAGE
> +void arch_free_page(struct page *page, int order);
> +void arch_alloc_page(struct page *page, int order);
> +#endif
> +
> #ifndef HAVE_ARCH_FREE_PAGE
> static inline void arch_free_page(struct page *page, int order) { }
> #endif
