From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0426CC74A51 for ; Thu, 11 Jul 2019 08:49:34 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id B02F121537 for ; Thu, 11 Jul 2019 08:49:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B02F121537 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 4663E8E00AC; Thu, 11 Jul 2019 04:49:33 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 416B28E0032; Thu, 11 Jul 2019 04:49:33 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2B81B8E00AC; Thu, 11 Jul 2019 04:49:33 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from mail-ua1-f72.google.com (mail-ua1-f72.google.com [209.85.222.72]) by kanga.kvack.org (Postfix) with ESMTP id EC9A58E0032 for ; Thu, 11 Jul 2019 04:49:32 -0400 (EDT) Received: by mail-ua1-f72.google.com with SMTP id s1so935676uao.2 for ; Thu, 11 Jul 2019 01:49:32 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-original-authentication-results:x-gm-message-state:date:from:to :cc:subject:message-id:in-reply-to:references:organization :mime-version:content-transfer-encoding; bh=uzboYqu/EnutsUfDvdzc2QGLrZgrkC1MIL9crIUqBoM=; b=FrZtIMNmRjV1fx/812Lwy9hCFlh3iXdvg14HBCE+yDbNuRcMSmLqz15cWsKPmyWkpd Z1U2e0mIjhr4PKOWgIqjE6lzoeSAZJzL7x7SyJfUUKfLGp4bKG0O+bssr18Na6QrthoD nmI8vAOSi/OimToIoFPum59i0rgzxv/0S8GoEK/bGFmD9DIBLudRxzVkcXxPZvDWkuUv J1L3kZ9WtT4fGXZU31i2LZymr53LpIRO1Q4WmKmYUpN4TG7DxfrSSx23Kg87i0ghVKQr KyrjsQZT3mfu03EocDEkrZl7791lvvadR2mcV6jK2G+PC0+1om0mC9DFGf0xcOJ0iq6M dsew== X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of cohuck@redhat.com designates 209.132.183.28 as permitted sender) smtp.mailfrom=cohuck@redhat.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com X-Gm-Message-State: APjAAAX0j9K3o2+x41tzlyt6DopR4ARvjFYoiEBhBB4J6jHtlFnc8yt3 66ygcyFT8CuLWJcgH3H5UlSSGpFJ3QeM5v6AURsi5dYB1eUGxTW2FTISy4+T9U7ZxaJ0ZbudqwY An+Rzm64DE290OI0FXpw0r3U4qdAnLlfrppW10O8DahpO4cc/+/EuU1Dpx2rfDGDNIw== X-Received: by 2002:a67:edcf:: with SMTP id e15mr2485845vsp.75.1562834972638; Thu, 11 Jul 2019 01:49:32 -0700 (PDT) X-Google-Smtp-Source: APXvYqyp6FWlBncMvBHopJ4gSA5rjwP3zKi8SZCvHDphE55A7XKE/dA5FjLVweDbHCwbV4Y8/rmT X-Received: by 2002:a67:edcf:: with SMTP id e15mr2485790vsp.75.1562834971989; Thu, 11 Jul 2019 01:49:31 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1562834971; cv=none; d=google.com; s=arc-20160816; b=yy2rs14mwwp8zeyLnmt2dYXM8W8JJW+c66t4A/fuJKQ09saUIm+vxQm1ZjoF7B5uLp fbjemenWSGFx8DWZXtgIuzDqUiUM21dRMGWNEinusSvJsCu56jx7tSU9DuuxUUhkJg4/ d2t9L/Pkhxgk5dTjnkpgAMBoc/B8muOOomLwgEiNTn+07WXwYnwlwwG7RbHY7f2jo5VE 9W8ULF+kHi0z+pupr5+7vKHsmXLomDpRI8T6AFl+go2iQBvamA5mmp4adQtIf5PJk4EQ o7JSOOSQKrmAW0AD4+N6wuk6L/k02W4K8AAY9duqVB2YJzQ34J+uJ/qiIdNdenGVqKw6 8fgA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-transfer-encoding:mime-version:organization:references :in-reply-to:message-id:subject:cc:to:from:date; bh=uzboYqu/EnutsUfDvdzc2QGLrZgrkC1MIL9crIUqBoM=; b=Ab6HJHVHPL1gcB4+xrxOnNK3AZ4DZ+g5UeNREqE998AVU4qOl4+hFRhB5lfZQbPWkL DppFFbtWMuebhqowykMzdndl7a+FFiWgL/+mDKuTPB+NMX00PTO1O4EQ7YdOgzA6FYAA MA515ksMCK2efI8Kd9jD7YQY63ixDFMxHGeEd/Yio4izKQ4qZ/+PsHk+teEEvksxEpN6 6JtkdPSv63ZgMBRNkWtHKn3PBGW5V+6YW+G+3xS78odXKw6S7RU0wdoVOGKuBskf1OgU H4IhrvADrFLdNN0Ef587EwpiYI/KjsYUF5dkNSL80M/5Dp+S5lCvko4K10Xwo+eQ0aKm 5ZHw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of cohuck@redhat.com designates 209.132.183.28 as permitted sender) smtp.mailfrom=cohuck@redhat.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: from mx1.redhat.com (mx1.redhat.com. [209.132.183.28]) by mx.google.com with ESMTPS id y23si1219633vsn.156.2019.07.11.01.49.31 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 11 Jul 2019 01:49:31 -0700 (PDT) Received-SPF: pass (google.com: domain of cohuck@redhat.com designates 209.132.183.28 as permitted sender) client-ip=209.132.183.28; Authentication-Results: mx.google.com; spf=pass (google.com: domain of cohuck@redhat.com designates 209.132.183.28 as permitted sender) smtp.mailfrom=cohuck@redhat.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 13A2D81F07; Thu, 11 Jul 2019 08:49:30 +0000 (UTC) Received: from gondolin (ovpn-117-213.ams2.redhat.com [10.36.117.213]) by smtp.corp.redhat.com (Postfix) with ESMTP id 324321001B05; Thu, 11 Jul 2019 08:49:15 +0000 (UTC) Date: Thu, 11 Jul 2019 10:49:12 +0200 From: Cornelia Huck To: Nitesh Narayan Lal Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.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, alexander.duyck@gmail.com, john.starks@microsoft.com, dave.hansen@intel.com, mhocko@suse.com Subject: Re: [QEMU Patch] virtio-baloon: Support for page hinting Message-ID: <20190711104912.2cd79aeb.cohuck@redhat.com> In-Reply-To: <20190710195303.19690-1-nitesh@redhat.com> References: <20190710195158.19640-1-nitesh@redhat.com> <20190710195303.19690-1-nitesh@redhat.com> Organization: Red Hat GmbH MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Thu, 11 Jul 2019 08:49:31 +0000 (UTC) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, 10 Jul 2019 15:53:03 -0400 Nitesh Narayan Lal wrote: $SUBJECT: s/baloon/balloon/ > Enables QEMU to perform madvise free on the memory range reported > by the vm. [No comments on the actual functionality; just some stuff I noticed.] > > Signed-off-by: Nitesh Narayan Lal > --- > hw/virtio/trace-events | 1 + > hw/virtio/virtio-balloon.c | 59 +++++++++++++++++++ > include/hw/virtio/virtio-balloon.h | 2 +- > include/qemu/osdep.h | 7 +++ > .../standard-headers/linux/virtio_balloon.h | 1 + > 5 files changed, 69 insertions(+), 1 deletion(-) > (...) > diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c > index 2112874055..5d186707b5 100644 > --- a/hw/virtio/virtio-balloon.c > +++ b/hw/virtio/virtio-balloon.c > @@ -34,6 +34,9 @@ > > #define BALLOON_PAGE_SIZE (1 << VIRTIO_BALLOON_PFN_SHIFT) > > +#define VIRTIO_BALLOON_PAGE_HINTING_MAX_PAGES 16 > +void free_mem_range(uint64_t addr, uint64_t len); > + > struct PartiallyBalloonedPage { > RAMBlock *rb; > ram_addr_t base; > @@ -328,6 +331,58 @@ static void balloon_stats_set_poll_interval(Object *obj, Visitor *v, > balloon_stats_change_timer(s, 0); > } > > +void free_mem_range(uint64_t addr, uint64_t len) > +{ > + int ret = 0; > + void *hvaddr_to_free; > + MemoryRegionSection mrs = memory_region_find(get_system_memory(), > + addr, 1); > + if (!mrs.mr) { > + warn_report("%s:No memory is mapped at address 0x%lu", __func__, addr); Indentation seems to be off here (also in other places; please double check.) > + return; > + } > + > + if (!memory_region_is_ram(mrs.mr) && !memory_region_is_romd(mrs.mr)) { > + warn_report("%s:Memory at address 0x%s is not RAM:0x%lu", __func__, > + HWADDR_PRIx, addr); > + memory_region_unref(mrs.mr); > + return; > + } > + > + hvaddr_to_free = qemu_map_ram_ptr(mrs.mr->ram_block, mrs.offset_within_region); > + trace_virtio_balloon_hinting_request(addr, len); > + ret = qemu_madvise(hvaddr_to_free,len, QEMU_MADV_FREE); > + if (ret == -1) { > + warn_report("%s: Madvise failed with error:%d", __func__, ret); > + } > +} > + > +static void virtio_balloon_handle_page_hinting(VirtIODevice *vdev, > + VirtQueue *vq) > +{ > + VirtQueueElement *elem; > + size_t offset = 0; > + uint64_t gpa, len; > + elem = virtqueue_pop(vq, sizeof(VirtQueueElement)); > + if (!elem) { > + return; > + } > + /* For pending hints which are < max_pages(16), 'gpa != 0' ensures that we > + * only read the buffer which holds a valid PFN value. > + * TODO: Find a better way to do this. > + */ > + while (iov_to_buf(elem->out_sg, elem->out_num, offset, &gpa, 8) == 8 && gpa != 0) { > + offset += 8; > + offset += iov_to_buf(elem->out_sg, elem->out_num, offset, &len, 8); > + if (!qemu_balloon_is_inhibited()) { > + free_mem_range(gpa, len); > + } > + } > + virtqueue_push(vq, elem, offset); > + virtio_notify(vdev, vq); > + g_free(elem); > +} > + > static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq) > { > VirtIOBalloon *s = VIRTIO_BALLOON(vdev); > @@ -694,6 +749,7 @@ 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); I don't think you can add this unconditionally if you want to keep this migratable. This should be done via a property (as for deflate-on-oom and free-page-hint) so it can be turned off in compat machines. > > return f; > } > @@ -780,6 +836,7 @@ 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_handle_page_hinting); This should probably be conditional in the same way as the free page hint queue (also see above). > > if (virtio_has_feature(s->host_features, > VIRTIO_BALLOON_F_FREE_PAGE_HINT)) { > @@ -875,6 +932,8 @@ 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); This object does not have any accessors; what purpose does it serve? > > object_property_add(obj, "guest-stats-polling-interval", "int", > balloon_stats_get_poll_interval, (...) > diff --git a/include/standard-headers/linux/virtio_balloon.h b/include/standard-headers/linux/virtio_balloon.h > index 9375ca2a70..f9e3e82562 100644 > --- a/include/standard-headers/linux/virtio_balloon.h > +++ b/include/standard-headers/linux/virtio_balloon.h > @@ -36,6 +36,7 @@ > #define VIRTIO_BALLOON_F_DEFLATE_ON_OOM 2 /* Deflate balloon on OOM */ > #define VIRTIO_BALLOON_F_FREE_PAGE_HINT 3 /* VQ to report free pages */ > #define VIRTIO_BALLOON_F_PAGE_POISON 4 /* Guest is using page poisoning */ > +#define VIRTIO_BALLOON_F_HINTING 5 /* Page hinting virtqueue */ > > /* Size of a PFN in the balloon interface. */ > #define VIRTIO_BALLOON_PFN_SHIFT 12 Please split off any update to these headers into a separate patch, so that it can be replaced by a proper headers update when it is merged.