From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by dpdk.org (Postfix) with ESMTP id EAAEA2BA9 for ; Thu, 10 Mar 2016 07:25:12 +0100 (CET) Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga101.jf.intel.com with ESMTP; 09 Mar 2016 22:25:12 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.24,314,1455004800"; d="scan'208";a="666872186" Received: from shwdeisgchi083.ccr.corp.intel.com (HELO [10.239.67.193]) ([10.239.67.193]) by FMSMGA003.fm.intel.com with ESMTP; 09 Mar 2016 22:25:10 -0800 To: Tetsuya Mukawa , dev@dpdk.org References: <1457590462-3680-1-git-send-email-mukawa@igel.co.jp> From: "Tan, Jianfeng" Message-ID: <56E11345.7030404@intel.com> Date: Thu, 10 Mar 2016 14:25:09 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: <1457590462-3680-1-git-send-email-mukawa@igel.co.jp> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [dpdk-dev] [PATCH] vhost: Fix default value of kickfd and callfd X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 10 Mar 2016 06:25:13 -0000 On 3/10/2016 2:14 PM, Tetsuya Mukawa wrote: > Currently, default value of kickfd and callfd is -1. > If the value is -1, current code guess kickfd and callfd hasn't been > initialized yet. And vhost library will guess the virtqueue isn't ready > for processing. > But callfd and kickfd will be set as -1 when "--enable-kvm" > isn't specified in QEMU command line. It means we cannot treat -1 as > uninitialized state. The patch changes default value to -2. And the > patch defines -2 as VIRTIO_UNINITIALIZED_EVENTFD. > > Signed-off-by: Tetsuya Mukawa > --- > lib/librte_vhost/rte_virtio_net.h | 1 + > lib/librte_vhost/vhost_user/virtio-net-user.c | 7 ++++--- > lib/librte_vhost/virtio-net.c | 4 ++-- > 3 files changed, 7 insertions(+), 5 deletions(-) > > diff --git a/lib/librte_vhost/rte_virtio_net.h b/lib/librte_vhost/rte_virtio_net.h > index 7d1fde2..d745707 100644 > --- a/lib/librte_vhost/rte_virtio_net.h > +++ b/lib/librte_vhost/rte_virtio_net.h > @@ -89,6 +89,7 @@ struct vhost_virtqueue { > uint16_t vhost_hlen; /**< Vhost header length (varies depending on RX merge buffers. */ > volatile uint16_t last_used_idx; /**< Last index used on the available ring */ > volatile uint16_t last_used_idx_res; /**< Used for multiple devices reserving buffers. */ > +#define VIRTIO_UNINITIALIZED_EVENTFD (-2) > int callfd; /**< Used to notify the guest (trigger interrupt). */ > int kickfd; /**< Currently unused as polling mode is enabled. */ > int enabled; > diff --git a/lib/librte_vhost/vhost_user/virtio-net-user.c b/lib/librte_vhost/vhost_user/virtio-net-user.c > index 65b5652..591f9bf 100644 > --- a/lib/librte_vhost/vhost_user/virtio-net-user.c > +++ b/lib/librte_vhost/vhost_user/virtio-net-user.c > @@ -225,8 +225,8 @@ static int > vq_is_ready(struct vhost_virtqueue *vq) > { > return vq && vq->desc && > - vq->kickfd != -1 && > - vq->callfd != -1; > + vq->kickfd != VIRTIO_UNINITIALIZED_EVENTFD && > + vq->callfd != VIRTIO_UNINITIALIZED_EVENTFD; > } > > static int > @@ -318,7 +318,8 @@ user_get_vring_base(struct vhost_device_ctx ctx, > */ > if (dev->virtqueue[state->index]->kickfd >= 0) { > close(dev->virtqueue[state->index]->kickfd); Then -1 will be a valid value, need to check if it's not -1 to close()? Nevertheless, close(-1) brings no big problem. Thanks, Jianfeng > - dev->virtqueue[state->index]->kickfd = -1; > + dev->virtqueue[state->index]->kickfd = > + VIRTIO_UNINITIALIZED_EVENTFD; > } > > return 0; > diff --git a/lib/librte_vhost/virtio-net.c b/lib/librte_vhost/virtio-net.c > index fe1a77e..3498e9d 100644 > --- a/lib/librte_vhost/virtio-net.c > +++ b/lib/librte_vhost/virtio-net.c > @@ -263,8 +263,8 @@ init_vring_queue(struct vhost_virtqueue *vq, int qp_idx) > { > memset(vq, 0, sizeof(struct vhost_virtqueue)); > > - vq->kickfd = -1; > - vq->callfd = -1; > + vq->kickfd = VIRTIO_UNINITIALIZED_EVENTFD; > + vq->callfd = VIRTIO_UNINITIALIZED_EVENTFD; > > /* Backends are set to -1 indicating an inactive device. */ > vq->backend = -1;