From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt1-f198.google.com (mail-qt1-f198.google.com [209.85.160.198]) by kanga.kvack.org (Postfix) with ESMTP id 3B1B38E0001 for ; Thu, 27 Dec 2018 07:05:52 -0500 (EST) Received: by mail-qt1-f198.google.com with SMTP id 42so23973549qtr.7 for ; Thu, 27 Dec 2018 04:05:52 -0800 (PST) Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com. [148.163.158.5]) by mx.google.com with ESMTPS id h39si5554973qth.232.2018.12.27.04.05.51 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 27 Dec 2018 04:05:51 -0800 (PST) Received: from pps.filterd (m0098420.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id wBRC5HtP118612 for ; Thu, 27 Dec 2018 07:05:50 -0500 Received: from e06smtp04.uk.ibm.com (e06smtp04.uk.ibm.com [195.75.94.100]) by mx0b-001b2d01.pphosted.com with ESMTP id 2pmushdxts-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 27 Dec 2018 07:05:45 -0500 Received: from localhost by e06smtp04.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 27 Dec 2018 12:03:56 -0000 Subject: Re: [PATCH v37 1/3] virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT References: <1535333539-32420-1-git-send-email-wei.w.wang@intel.com> <1535333539-32420-2-git-send-email-wei.w.wang@intel.com> From: Christian Borntraeger Date: Thu, 27 Dec 2018 13:03:44 +0100 MIME-Version: 1.0 In-Reply-To: <1535333539-32420-2-git-send-email-wei.w.wang@intel.com> Content-Language: en-US Message-Id: <49d706f7-a0ee-e571-7d02-bcadac5ce742@de.ibm.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: Wei Wang , virtio-dev@lists.oasis-open.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, linux-mm@kvack.org, mst@redhat.com, mhocko@kernel.org, akpm@linux-foundation.org, dgilbert@redhat.com Cc: torvalds@linux-foundation.org, pbonzini@redhat.com, liliang.opensource@gmail.com, yang.zhang.wz@gmail.com, quan.xu0@gmail.com, nilal@redhat.com, riel@redhat.com, peterx@redhat.com, quintela@redhat.com, Cornelia Huck , Halil Pasic On 27.08.2018 03:32, Wei Wang wrote: > static int init_vqs(struct virtio_balloon *vb) > { > - struct virtqueue *vqs[3]; > - vq_callback_t *callbacks[] = { balloon_ack, balloon_ack, stats_request }; > - static const char * const names[] = { "inflate", "deflate", "stats" }; > - int err, nvqs; > + struct virtqueue *vqs[VIRTIO_BALLOON_VQ_MAX]; > + vq_callback_t *callbacks[VIRTIO_BALLOON_VQ_MAX]; > + const char *names[VIRTIO_BALLOON_VQ_MAX]; > + int err; > > /* > - * We expect two virtqueues: inflate and deflate, and > - * optionally stat. > + * Inflateq and deflateq are used unconditionally. The names[] > + * will be NULL if the related feature is not enabled, which will > + * cause no allocation for the corresponding virtqueue in find_vqs. > */ This might be true for virtio-pci, but it is not for virtio-ccw. > - nvqs = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_STATS_VQ) ? 3 : 2; > - err = virtio_find_vqs(vb->vdev, nvqs, vqs, callbacks, names, NULL); > + callbacks[VIRTIO_BALLOON_VQ_INFLATE] = balloon_ack; > + names[VIRTIO_BALLOON_VQ_INFLATE] = "inflate"; > + callbacks[VIRTIO_BALLOON_VQ_DEFLATE] = balloon_ack; > + names[VIRTIO_BALLOON_VQ_DEFLATE] = "deflate"; > + names[VIRTIO_BALLOON_VQ_STATS] = NULL; > + names[VIRTIO_BALLOON_VQ_FREE_PAGE] = NULL; > + > + if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_STATS_VQ)) { > + names[VIRTIO_BALLOON_VQ_STATS] = "stats"; > + callbacks[VIRTIO_BALLOON_VQ_STATS] = stats_request; > + } > + > + if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) { > + names[VIRTIO_BALLOON_VQ_FREE_PAGE] = "free_page_vq"; > + callbacks[VIRTIO_BALLOON_VQ_FREE_PAGE] = NULL; > + } > + > + err = vb->vdev->config->find_vqs(vb->vdev, VIRTIO_BALLOON_VQ_MAX, [...]