From patchwork Mon Feb 4 20:20:38 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nitesh Narayan Lal X-Patchwork-Id: 10796545 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9E40C6C2 for ; Mon, 4 Feb 2019 20:20:57 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8DDEF2C244 for ; Mon, 4 Feb 2019 20:20:57 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 81ACF2C242; Mon, 4 Feb 2019 20:20:57 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CE2BD2C1EF for ; Mon, 4 Feb 2019 20:20:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728880AbfBDUUz (ORCPT ); Mon, 4 Feb 2019 15:20:55 -0500 Received: from mx1.redhat.com ([209.132.183.28]:52276 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728848AbfBDUUy (ORCPT ); Mon, 4 Feb 2019 15:20:54 -0500 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id A74202CD811; Mon, 4 Feb 2019 20:20:53 +0000 (UTC) Received: from virtlab420.virt.lab.eng.bos.redhat.com (virtlab420.virt.lab.eng.bos.redhat.com [10.19.152.148]) by smtp.corp.redhat.com (Postfix) with ESMTP id 757238E8F3; Mon, 4 Feb 2019 20:20:51 +0000 (UTC) From: Nitesh Narayan Lal To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, pbonzini@redhat.com, lcapitulino@redhat.com, pagupta@redhat.com, wei.w.wang@intel.com, yang.zhang.wz@gmail.com, riel@surriel.com, david@redhat.com, mst@redhat.com, dodgen@google.com, konrad.wilk@oracle.com, dhildenb@redhat.com, aarcange@redhat.com Cc: Nitesh Narayan Lal Subject: [RFC][QEMU PATCH] KVM: Support for guest free page hinting Date: Mon, 4 Feb 2019 15:20:38 -0500 Message-Id: <20190204202038.2471-1-nitesh@redhat.com> In-Reply-To: <20190204201854.2328-1-nitesh@redhat.com> References: <20190204201854.2328-1-nitesh@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.29]); Mon, 04 Feb 2019 20:20:54 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch enables QEMU to recieve free page address from the guest and to use madvise to make them available to the host. --- hw/virtio/trace-events | 1 + hw/virtio/virtio-balloon.c | 82 +++++++++++++++++++ hw/virtio/virtio.c | 25 ++++++ include/hw/virtio/virtio-access.h | 1 + include/hw/virtio/virtio-balloon.h | 2 +- .../standard-headers/linux/virtio_balloon.h | 1 + 6 files changed, 111 insertions(+), 1 deletion(-) diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events index 07bcbe9e85..e3ab66f126 100644 --- a/hw/virtio/trace-events +++ b/hw/virtio/trace-events @@ -46,3 +46,4 @@ virtio_balloon_handle_output(const char *name, uint64_t gpa) "section name: %s g virtio_balloon_get_config(uint32_t num_pages, uint32_t actual) "num_pages: %d actual: %d" virtio_balloon_set_config(uint32_t actual, uint32_t oldactual) "actual: %d oldactual: %d" virtio_balloon_to_target(uint64_t target, uint32_t num_pages) "balloon target: 0x%"PRIx64" num_pages: %d" +virtio_balloon_hinting_request(unsigned long pfn, unsigned int num_pages) "Guest page hinting request: %lu num_pages: %d" diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c index a12677d4d5..464d7d0d82 100644 --- a/hw/virtio/virtio-balloon.c +++ b/hw/virtio/virtio-balloon.c @@ -33,6 +33,13 @@ #define BALLOON_PAGE_SIZE (1 << VIRTIO_BALLOON_PFN_SHIFT) +struct guest_pages { + unsigned long pfn; + unsigned int order; +}; + +void page_hinting_request(uint64_t addr, uint32_t len); + static void balloon_page(void *addr, int deflate) { if (!qemu_balloon_is_inhibited()) { @@ -207,6 +214,77 @@ static void balloon_stats_set_poll_interval(Object *obj, Visitor *v, balloon_stats_change_timer(s, 0); } +static void *gpa2hva(MemoryRegion **p_mr, hwaddr addr, Error **errp) +{ + MemoryRegionSection mrs = memory_region_find(get_system_memory(), + addr, 1); + + if (!mrs.mr) { + error_setg(errp, "No memory is mapped at address 0x%" HWADDR_PRIx, addr); + return NULL; + } + + if (!memory_region_is_ram(mrs.mr) && !memory_region_is_romd(mrs.mr)) { + error_setg(errp, "Memory at address 0x%" HWADDR_PRIx "is not RAM", addr); + memory_region_unref(mrs.mr); + return NULL; + } + + *p_mr = mrs.mr; + return qemu_map_ram_ptr(mrs.mr->ram_block, mrs.offset_within_region); +} + +void page_hinting_request(uint64_t addr, uint32_t len) +{ + Error *local_err = NULL; + MemoryRegion *mr = NULL; + void *hvaddr; + int ret = 0; + struct guest_pages *guest_obj; + int i = 0; + void *hvaddr_to_free; + unsigned long pfn, pfn_end; + uint64_t gpaddr_to_free; + + hvaddr = gpa2hva(&mr, addr, &local_err); + if (local_err) { + error_report_err(local_err); + return; + } + guest_obj = hvaddr; + + while (i < len) { + pfn = guest_obj[i].pfn; + pfn_end = guest_obj[i].pfn + (1 << guest_obj[i].order) - 1; + trace_virtio_balloon_hinting_request(pfn,(1 << guest_obj[i].order)); + while (pfn <= pfn_end) { + gpaddr_to_free = pfn << VIRTIO_BALLOON_PFN_SHIFT; + hvaddr_to_free = gpa2hva(&mr, gpaddr_to_free, &local_err); + if (local_err) { + error_report_err(local_err); + return; + } + ret = qemu_madvise((void *)hvaddr_to_free, 4096, QEMU_MADV_DONTNEED); + if (ret == -1) + printf("\n%d:%s Error: Madvise failed with error:%d\n", __LINE__, __func__, ret); + pfn++; + } + i++; + } +} + +static void virtio_balloon_page_hinting(VirtIODevice *vdev, VirtQueue *vq) +{ + uint64_t addr; + uint32_t len; + VirtQueueElement elem = {}; + + pop_hinting_addr(vq, &addr, &len); + page_hinting_request(addr, len); + virtqueue_push(vq, &elem, 0); + virtio_notify(vdev, vq); +} + static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq) { VirtIOBalloon *s = VIRTIO_BALLOON(vdev); @@ -376,6 +454,7 @@ static uint64_t virtio_balloon_get_features(VirtIODevice *vdev, uint64_t f, VirtIOBalloon *dev = VIRTIO_BALLOON(vdev); f |= dev->host_features; virtio_add_feature(&f, VIRTIO_BALLOON_F_STATS_VQ); + virtio_add_feature(&f, VIRTIO_BALLOON_F_HINTING); return f; } @@ -445,6 +524,7 @@ static void virtio_balloon_device_realize(DeviceState *dev, Error **errp) s->ivq = virtio_add_queue(vdev, 128, virtio_balloon_handle_output); s->dvq = virtio_add_queue(vdev, 128, virtio_balloon_handle_output); s->svq = virtio_add_queue(vdev, 128, virtio_balloon_receive_stats); + s->hvq = virtio_add_queue(vdev, 128, virtio_balloon_page_hinting); reset_stats(s); } @@ -488,6 +568,8 @@ static void virtio_balloon_instance_init(Object *obj) object_property_add(obj, "guest-stats", "guest statistics", balloon_stats_get_all, NULL, NULL, s, NULL); + object_property_add(obj, "guest-page-hinting", "guest page hinting", + NULL, NULL, NULL, s, NULL); object_property_add(obj, "guest-stats-polling-interval", "int", balloon_stats_get_poll_interval, diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 22bd1ac34e..a0cdb232f0 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -847,6 +847,31 @@ static void *virtqueue_alloc_element(size_t sz, unsigned out_num, unsigned in_nu return elem; } +void pop_hinting_addr(VirtQueue *vq, uint64_t *addr, uint32_t *len) +{ + VRingMemoryRegionCaches *caches; + VRingDesc desc; + MemoryRegionCache *desc_cache; + VirtIODevice *vdev = vq->vdev; + unsigned int head, max; + + max = vq->vring.num; + if (!virtqueue_get_head(vq, vq->last_avail_idx++, &head)) { + virtio_error(vdev, "Unable to read head"); + return; + } + + caches = vring_get_region_caches(vq); + if (caches->desc.len < max * sizeof(VRingDesc)) { + virtio_error(vdev, "Cannot map descriptor ring"); + return; + } + desc_cache = &caches->desc; + vring_desc_read(vdev, &desc, desc_cache, head); + *addr = desc.addr; + *len = desc.len; +} + void *virtqueue_pop(VirtQueue *vq, size_t sz) { unsigned int i, head, max; diff --git a/include/hw/virtio/virtio-access.h b/include/hw/virtio/virtio-access.h index bdf58f3119..0a55f2626f 100644 --- a/include/hw/virtio/virtio-access.h +++ b/include/hw/virtio/virtio-access.h @@ -23,6 +23,7 @@ #define LEGACY_VIRTIO_IS_BIENDIAN 1 #endif +void pop_hinting_addr(VirtQueue *vq, uint64_t *addr, uint32_t *len); static inline bool virtio_access_is_big_endian(VirtIODevice *vdev) { #if defined(LEGACY_VIRTIO_IS_BIENDIAN) diff --git a/include/hw/virtio/virtio-balloon.h b/include/hw/virtio/virtio-balloon.h index e0df3528c8..774498a6ca 100644 --- a/include/hw/virtio/virtio-balloon.h +++ b/include/hw/virtio/virtio-balloon.h @@ -32,7 +32,7 @@ typedef struct virtio_balloon_stat_modern { typedef struct VirtIOBalloon { VirtIODevice parent_obj; - VirtQueue *ivq, *dvq, *svq; + VirtQueue *ivq, *dvq, *svq, *hvq; uint32_t num_pages; uint32_t actual; uint64_t stats[VIRTIO_BALLOON_S_NR]; diff --git a/include/standard-headers/linux/virtio_balloon.h b/include/standard-headers/linux/virtio_balloon.h index 4dbb7dc6c0..f50c0d95ea 100644 --- a/include/standard-headers/linux/virtio_balloon.h +++ b/include/standard-headers/linux/virtio_balloon.h @@ -34,6 +34,7 @@ #define VIRTIO_BALLOON_F_MUST_TELL_HOST 0 /* Tell before reclaiming pages */ #define VIRTIO_BALLOON_F_STATS_VQ 1 /* Memory Stats virtqueue */ #define VIRTIO_BALLOON_F_DEFLATE_ON_OOM 2 /* Deflate balloon on OOM */ +#define VIRTIO_BALLOON_F_HINTING 5 /* Page hinting virtqueue */ /* Size of a PFN in the balloon interface. */ #define VIRTIO_BALLOON_PFN_SHIFT 12