From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Wang Subject: Re: [PATCH net-next v3 1/4] net: vhost: lock the vqs one by one Date: Mon, 2 Jul 2018 10:21:04 +0800 Message-ID: <25e69ba2-5ad3-17c6-0cc0-a02c9741b550@redhat.com> References: <1530340438-3039-1-git-send-email-xiangxia.m.yue@gmail.com> <1530340438-3039-2-git-send-email-xiangxia.m.yue@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Cc: mst@redhat.com, makita.toshiaki@lab.ntt.co.jp, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, Tonghao Zhang To: xiangxia.m.yue@gmail.com Return-path: Received: from mx3-rdu2.redhat.com ([66.187.233.73]:36286 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932421AbeGBCVN (ORCPT ); Sun, 1 Jul 2018 22:21:13 -0400 In-Reply-To: <1530340438-3039-2-git-send-email-xiangxia.m.yue@gmail.com> Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: On 2018年06月30日 14:33, xiangxia.m.yue@gmail.com wrote: > From: Tonghao Zhang > > This patch changes the way that lock all vqs > at the same, to lock them one by one. It will > be used for next patch to avoid the deadlock. > > Signed-off-by: Tonghao Zhang > --- > drivers/vhost/vhost.c | 24 +++++++----------------- > 1 file changed, 7 insertions(+), 17 deletions(-) > > diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c > index 895eaa2..4ca9383 100644 > --- a/drivers/vhost/vhost.c > +++ b/drivers/vhost/vhost.c > @@ -294,8 +294,11 @@ static void vhost_vq_meta_reset(struct vhost_dev *d) > { > int i; > > - for (i = 0; i < d->nvqs; ++i) > + for (i = 0; i < d->nvqs; ++i) { > + mutex_lock(&d->vqs[i]->mutex); > __vhost_vq_meta_reset(d->vqs[i]); > + mutex_unlock(&d->vqs[i]->mutex); > + } > } > > static void vhost_vq_reset(struct vhost_dev *dev, > @@ -887,20 +890,6 @@ static inline void __user *__vhost_get_user(struct vhost_virtqueue *vq, > #define vhost_get_used(vq, x, ptr) \ > vhost_get_user(vq, x, ptr, VHOST_ADDR_USED) > > -static void vhost_dev_lock_vqs(struct vhost_dev *d) > -{ > - int i = 0; > - for (i = 0; i < d->nvqs; ++i) > - mutex_lock_nested(&d->vqs[i]->mutex, i); > -} > - > -static void vhost_dev_unlock_vqs(struct vhost_dev *d) > -{ > - int i = 0; > - for (i = 0; i < d->nvqs; ++i) > - mutex_unlock(&d->vqs[i]->mutex); > -} > - > static int vhost_new_umem_range(struct vhost_umem *umem, > u64 start, u64 size, u64 end, > u64 userspace_addr, int perm) > @@ -950,7 +939,10 @@ static void vhost_iotlb_notify_vq(struct vhost_dev *d, > if (msg->iova <= vq_msg->iova && > msg->iova + msg->size - 1 > vq_msg->iova && > vq_msg->type == VHOST_IOTLB_MISS) { > + mutex_lock(&node->vq->mutex); > vhost_poll_queue(&node->vq->poll); > + mutex_unlock(&node->vq->mutex); > + > list_del(&node->node); > kfree(node); > } > @@ -982,7 +974,6 @@ static int vhost_process_iotlb_msg(struct vhost_dev *dev, > int ret = 0; > > mutex_lock(&dev->mutex); > - vhost_dev_lock_vqs(dev); > switch (msg->type) { > case VHOST_IOTLB_UPDATE: > if (!dev->iotlb) { > @@ -1016,7 +1007,6 @@ static int vhost_process_iotlb_msg(struct vhost_dev *dev, > break; > } > > - vhost_dev_unlock_vqs(dev); > mutex_unlock(&dev->mutex); > > return ret; Acked-by: Jason Wang Signed-off-by: Jason Wang Thanks