From mboxrd@z Thu Jan 1 00:00:00 1970 From: Linhaifeng Subject: vhost: virtio-net rx-ring stop work after work many hours, bug? Date: Tue, 27 Jan 2015 15:57:13 +0800 Message-ID: <54C744D9.3060900@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: liuyongan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org To: "dpd >> dev-VfR2kkLFssw@public.gmane.org" , "ms >> Michael S. Tsirkin" Return-path: List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces-VfR2kkLFssw@public.gmane.org Sender: "dev" Hi,all I use vhost-user to send data to VM at first it cant work well but after many hours VM can not receive data but can send data. (gdb)p avail_idx $4 = 2668 (gdb)p free_entries $5 = 0 (gdb)l /* check that we have enough buffers */ if (unlikely(count > free_entries)) count = free_entries; if (count == 0){ int b=0; if(b) { // when set b=1 to notify guest rx_ring will restart to work if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT)) { eventfd_write(vq->callfd, 1); } } return 0; } some info i print in guest: net eth3:vi->num=199 net eth3:rvq info: num_free=57, used->idx=2668, avail->idx=2668 net eth3:svq info: num_free=254, used->idx=1644, avail->idx=1644 net eth3:vi->num=199 net eth3:rvq info: num_free=57, used->idx=2668, avail->idx=2668 net eth3:svq info: num_free=254, used->idx=1645, avail->idx=1645 net eth3:vi->num=199 net eth3:rvq info: num_free=57, used->idx=2668, avail->idx=2668 net eth3:svq info: num_free=254, used->idx=1646, avail->idx=1646 # free total used free shared buffers cached Mem: 3924100 337252 3586848 0 95984 138060 -/+ buffers/cache: 103208 3820892 Swap: 970748 0 970748 I have two questions: 1.Should we need to notify guest when there is no buffer in vq->avail? 2.Why virtio_net stop to fill avail? -- Regards, Haifeng