[dpdk-dev] 100% cpu of VM (OS windows 7)

[Wei Li]

If using linux bridge, there is no problem also.

ping from host to guest, when ovs call "eventfd_write((int)vq->callfd, 
1)", guest crash and cpu usagerate of qemu is 100%

#0  rte_vhost_enqueue_burst (dev=0x7fe970000900, queue_id=0, 
pkts=0x7fff12521870, count=1) at 
/usr/src/dpdk/lib/librte_vhost/vhost_rxtx.c:543
#1  0x0000000000654f75 in __netdev_dpdk_vhost_send 
(netdev=0x7fe740afed00, pkts=0x7fff12521870, cnt=1, may_steal=true) at 
lib/netdev-dpdk.c:970
#2  0x00000000006553f8 in dpdk_do_tx_copy (netdev=0x7fe740afed00, 
qid=16, pkts=0x7fff12523390, cnt=1) at lib/netdev-dpdk.c:1085
#3  0x000000000065549a in netdev_dpdk_vhost_send (netdev=0x7fe740afed00, 
qid=16, pkts=0x7fff12523390, cnt=1, may_steal=true) at 
lib/netdev-dpdk.c:1103
#4  0x000000000058842c in netdev_send (netdev=0x7fe740afed00, qid=16, 
buffers=0x7fff12523390, cnt=1, may_steal=true) at lib/netdev.c:742
#5  0x000000000055ff52 in dp_execute_cb (aux_=0x7fff12521f50, 
packets=0x7fff12523390, cnt=1, a=0x7fff12522058, may_steal=true) at 
lib/dpif-netdev.c:3434

On 2015/7/1 18:34, Wei Li wrote:
> dpdk: 2.0.0
> ovs:    2.4.90
> qemu:   2.3.0
> OS of vm: windows7 64bit
> driver of virtio for windows: virtio-win-0.1.96_amd64
>
> ovs-vsctl add-br br0 -- set bridge br0 datapath_type=netdev
> ovs-vsctl add-port br0 tap0 -- set Interface tap0 type=dpdkvhostuser
> qemu-system-x86_64 win.img -cpu host -smp 2 --enable-kvm -m 2G -vnc :1 
> -object 
> memory-backend-file,id=mem,size=2G,mem-path=/dev/hugepages,share=on 
> -numa node,memdev=mem -mem-prealloc -chardev 
> socket,id=char1,path=/var/run/openvswitch/tap0 -netdev 
> type=vhost-user,id=net1,chardev=char1,vhostforce -device 
> virtio-net-pci,netdev=net1,mac=00:00:00:00:00:01,csum=off,gso=off,guest_tso4=off,guest_tso6=off,guest_ecn=off 
> &
>
>
> |-----|    |-----|
> | VM  |----| ovs |    use vhostuser
> |-----|    |-----|
>
> When VM receiving packets from virtionet, the cpu of vm get 100%, but 
> sending packets looks like ok
>
> if the OS of VM is Linux, there is no problem
>
> what different between windows 7 and linux?
>
> Have anyone meet the problem?