From mboxrd@z Thu Jan 1 00:00:00 1970 From: nilal@redhat.com Subject: [Patch v6 1/7] KVM: Support for guest page hinting Date: Fri, 1 Dec 2017 12:31:30 -0500 Message-ID: <20171201173136.849-2-nilal@redhat.com> References: <20171201173136.849-1-nilal@redhat.com> To: kvm@vger.kernel.org, pbonzini@redhat.com, pagupta@redhat.com, wei.w.wang@intel.com, yang.zhang.wz@gmail.com, riel@redhat.com, david@redhat.com, mst@redhat.com, dodgen@google.com, konrad.wilk@oracle.com Return-path: Received: from mx1.redhat.com ([209.132.183.28]:55498 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751432AbdLARbl (ORCPT ); Fri, 1 Dec 2017 12:31:41 -0500 In-Reply-To: <20171201173136.849-1-nilal@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: From: Nitesh Narayan Lal 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 --- arch/x86/Kbuild | 2 +- arch/x86/kvm/Kconfig | 6 ++++++ arch/x86/kvm/Makefile | 2 ++ include/linux/gfp.h | 7 +++++++ virt/kvm/page_hinting.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 62 insertions(+), 1 deletion(-) create mode 100644 virt/kvm/page_hinting.c 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-$(CONFIG_XEN) += xen/ diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig index 3df51c2..a282713 100644 --- a/arch/x86/kvm/Kconfig +++ b/arch/x86/kvm/Kconfig @@ -88,6 +88,12 @@ config KVM_MMU_AUDIT This option adds a R/W kVM module parameter 'mmu_audit', which allows auditing of KVM MMU events at runtime. +config KVM_FREE_PAGE_HINTING + def_bool y + depends on KVM + select VIRTIO + select VIRTIO_BALLOON + # OK, it's a little counter-intuitive to do this, but it puts it neatly under # the virtualization menu. source drivers/vhost/Kconfig diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile index dc4f2fd..866dd56 100644 --- a/arch/x86/kvm/Makefile +++ b/arch/x86/kvm/Makefile @@ -16,6 +16,8 @@ kvm-y += x86.o mmu.o emulate.o i8259.o irq.o lapic.o \ i8254.o ioapic.o irq_comm.o cpuid.o pmu.o mtrr.o \ hyperv.o page_track.o debugfs.o +obj-$(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 1a4582b..e02369b 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 diff --git a/virt/kvm/page_hinting.c b/virt/kvm/page_hinting.c new file mode 100644 index 0000000..39d2b1d --- /dev/null +++ b/virt/kvm/page_hinting.c @@ -0,0 +1,46 @@ +#include +#include +#include +#include +#include + +#include + +#define MAX_FGPT_ENTRIES 1000 +#define HYPERLIST_THRESHOLD 500 +/* + * struct kvm_free_pages - Tracks the pages which are freed by the guest. + * @pfn - page frame number for the page which is to be freed + * @pages - number of pages which are supposed to be freed. + * A global array object is used to hold the list of pfn and number of pages + * which are freed by the guest. This list may also have fragmentated pages so + * defragmentation is a must prior to the hypercall. + */ +struct kvm_free_pages { + unsigned long pfn; + unsigned int pages; +}; + +/* + * hypervisor_pages - It is a dummy structure passed with the hypercall. + * @pfn - page frame number for the page which is to be freed. + * @pages - number of pages which are supposed to be freed. + * A global array object is used to to hold the list of pfn and pages and is + * passed as part of the hypercall. + */ +struct hypervisor_pages { + unsigned long pfn; + unsigned int pages; +}; + +DEFINE_PER_CPU(struct kvm_free_pages [MAX_FGPT_ENTRIES], kvm_pt); +DEFINE_PER_CPU(int, kvm_pt_idx); +struct hypervisor_pages hypervisor_pagelist[MAX_FGPT_ENTRIES]; + +void arch_alloc_page(struct page *page, int order) +{ +} + +void arch_free_page(struct page *page, int order) +{ +} -- 2.9.4