X-Git-Url: http://git.droids-corp.org/?a=blobdiff_plain;f=doc%2Fguides%2Fsample_app_ug%2Fvhost.rst;h=b7ed4f8bdf76b387dca88ba3aaa80eb1dea06fc9;hb=d7e66b69ddc947a1263e8d489483a5bd7c7aa6b5;hp=5e7f24c4e8bd75f940b176c1aba655c3825d78d2;hpb=e3075e969eff1d4746b58172a188a4dc12194ef6;p=dpdk.git diff --git a/doc/guides/sample_app_ug/vhost.rst b/doc/guides/sample_app_ug/vhost.rst index 5e7f24c4e8..b7ed4f8bdf 100644 --- a/doc/guides/sample_app_ug/vhost.rst +++ b/doc/guides/sample_app_ug/vhost.rst @@ -78,7 +78,7 @@ could be done by: .. code-block:: console modprobe uio_pci_generic - $RTE_SDK/usertools/dpdk-devbind.py -b=uio_pci_generic 0000:00:04.0 + $RTE_SDK/usertools/dpdk-devbind.py -b uio_pci_generic 0000:00:04.0 Then start testpmd for packet forwarding testing. @@ -116,7 +116,7 @@ will create it. Put simply, it's the server to create the socket file. The vm2vm parameter sets the mode of packet switching between guests in the host. -- 0 disables vm2vm, impling that VM's packets will always go to the NIC port. +- 0 disables vm2vm, implying that VM's packets will always go to the NIC port. - 1 means a normal mac lookup packet routing. - 2 means hardware mode packet forwarding between guests, it allows packets go to the NIC port, hardware L2 switch will determine which guest the @@ -148,7 +148,7 @@ default value is 15. **--dequeue-zero-copy** Dequeue zero copy will be enabled when this option is given. it is worth to -note that if NIC is binded to driver with iommu enabled, dequeue zero copy +note that if NIC is bound to driver with iommu enabled, dequeue zero copy cannot work at VM2NIC mode (vm2vm=0) due to currently we don't setup iommu dma mapping for guest memory. @@ -158,6 +158,10 @@ when disabling VLAN strip. Such feature, which heavily depends on hardware, should be removed from this example to reduce confusion. Now, VLAN strip is enabled and cannot be disabled. +**--builtin-net-driver** +A very simple vhost-user net driver which demonstrates how to use the generic +vhost APIs will be used when this option is given. It is disabled by default. + Common Issues ------------- @@ -181,3 +185,26 @@ Common Issues * Failed to build DPDK in VM Make sure "-cpu host" QEMU option is given. + +* Device start fails if NIC's max queues > the default number of 128 + + mbuf pool size is dependent on the MAX_QUEUES configuration, if NIC's + max queue number is larger than 128, device start will fail due to + insufficient mbuf. + + Change the default number to make it work as below, just set the number + according to the NIC's property. :: + + make EXTRA_CFLAGS="-DMAX_QUEUES=320" + +* Option "builtin-net-driver" is incompatible with QEMU + + QEMU vhost net device start will fail if protocol feature is not negotiated. + DPDK virtio-user pmd can be the replacement of QEMU. + +* Device start fails when enabling "builtin-net-driver" without memory + pre-allocation + + The builtin example doesn't support dynamic memory allocation. When vhost + backend enables "builtin-net-driver", "--socket-mem" option should be + added at virtio-user pmd side as a startup item.