```
## <a name="vhost"></a> 6. Vhost Walkthrough
-
-DPDK 16.07 supports two types of vhost:
-
-1. vhost-user - enabled default
-
-2. vhost-cuse - Legacy, disabled by default
-
### 6.1 vhost-user
- Prerequisites:
Note: For information on libvirt and further tuning refer [libvirt].
-### 6.2 vhost-cuse
-
- - Prerequisites:
-
- QEMU version >= 2.2
-
- - Enable vhost-cuse support
-
- 1. Enable vhost cuse support in DPDK
-
- Set `CONFIG_RTE_LIBRTE_VHOST_USER=n` in config/common_linuxapp and follow the
- steps in 2.2 section of INSTALL.DPDK guide to build DPDK with cuse support.
- OVS will detect that DPDK has vhost-cuse libraries compiled and in turn will enable
- support for it in the switch and disable vhost-user support.
-
- 2. Insert the Cuse module
-
- `modprobe cuse`
-
- 3. Build and insert the `eventfd_link` module
-
- ```
- cd $DPDK_DIR/lib/librte_vhost/eventfd_link/
- make
- insmod $DPDK_DIR/lib/librte_vhost/eventfd_link.ko
- ```
-
- - Adding vhost-cuse ports to Switch
-
- Unlike DPDK ring ports, DPDK vhost-cuse ports can have arbitrary names.
- For vhost-cuse, the name of the port type is `dpdkvhostcuse`
-
- ```
- ovs-vsctl add-port br0 vhost-cuse-1 -- set Interface vhost-cuse-1
- type=dpdkvhostcuse
- ```
-
- When attaching vhost-cuse ports to QEMU, the name provided during the
- add-port operation must match the ifname parameter on the QEMU cmd line.
-
- - Adding vhost-cuse ports to VM
-
- vhost-cuse ports use a Linux* character device to communicate with QEMU.
- By default it is set to `/dev/vhost-net`. It is possible to reuse this
- standard device for DPDK vhost, which makes setup a little simpler but it
- is better practice to specify an alternative character device in order to
- avoid any conflicts if kernel vhost is to be used in parallel.
-
- 1. This step is only needed if using an alternative character device.
-
- ```
- ./utilities/ovs-vsctl --no-wait set Open_vSwitch . \
- other_config:cuse-dev-name=my-vhost-net
- ```
-
- In the example above, the character device to be used will be
- `/dev/my-vhost-net`.
-
- 2. In case of reusing kernel vhost character device, there would be conflict
- user should remove it.
-
- `rm -rf /dev/vhost-net`
-
- 3. Configure virtio-net adapters
-
- The following parameters must be passed to the QEMU binary, repeat
- the below parameters for multiple devices.
-
- ```
- -netdev tap,id=<id>,script=no,downscript=no,ifname=<name>,vhost=on
- -device virtio-net-pci,netdev=net1,mac=<mac>
- ```
-
- The DPDK vhost library will negotiate its own features, so they
- need not be passed in as command line params. Note that as offloads
- are disabled this is the equivalent of setting
-
- `csum=off,gso=off,guest_tso4=off,guest_tso6=off,guest_ecn=off`
-
- When using an alternative character device, it must be explicitly
- passed to QEMU using the `vhostfd` argument
-
- ```
- -netdev tap,id=<id>,script=no,downscript=no,ifname=<name>,vhost=on,
- vhostfd=<open_fd> -device virtio-net-pci,netdev=net1,mac=<mac>
- ```
-
- The open file descriptor must be passed to QEMU running as a child
- process. This could be done with a simple python script.
-
- ```
- #!/usr/bin/python
- fd = os.open("/dev/usvhost", os.O_RDWR)
- subprocess.call("qemu-system-x86_64 .... -netdev tap,id=vhostnet0,\
- vhost=on,vhostfd=" + fd +"...", shell=True)
- ```
-
- 4. Configure huge pages
-
- QEMU must allocate the VM's memory on hugetlbfs. Vhost ports access a
- virtio-net device's virtual rings and packet buffers mapping the VM's
- physical memory on hugetlbfs. To enable vhost-ports to map the VM's
- memory into their process address space, pass the following parameters
- to QEMU
-
- `-object memory-backend-file,id=mem,size=4096M,mem-path=/dev/hugepages,
- share=on -numa node,memdev=mem -mem-prealloc`
-
- - VM Configuration with QEMU wrapper
-
- The QEMU wrapper script automatically detects and calls QEMU with the
- necessary parameters. It performs the following actions:
-
- * Automatically detects the location of the hugetlbfs and inserts this
- into the command line parameters.
- * Automatically open file descriptors for each virtio-net device and
- inserts this into the command line parameters.
- * Calls QEMU passing both the command line parameters passed to the
- script itself and those it has auto-detected.
-
- Before use, you **must** edit the configuration parameters section of the
- script to point to the correct emulator location and set additional
- settings. Of these settings, `emul_path` and `us_vhost_path` **must** be
- set. All other settings are optional.
-
- To use directly from the command line simply pass the wrapper some of the
- QEMU parameters: it will configure the rest. For example:
-
- ```
- qemu-wrap.py -cpu host -boot c -hda <disk image> -m 4096 -smp 4
- --enable-kvm -nographic -vnc none -net none -netdev tap,id=net1,
- script=no,downscript=no,ifname=if1,vhost=on -device virtio-net-pci,
- netdev=net1,mac=00:00:00:00:00:01
- ```
-
- - VM Configuration with libvirt
-
- If you are using libvirt, you must enable libvirt to access the character
- device by adding it to controllers cgroup for libvirtd using the following
- steps.
-
- 1. In `/etc/libvirt/qemu.conf` add/edit the following lines:
-
- ```
- clear_emulator_capabilities = 0
- user = "root"
- group = "root"
- cgroup_device_acl = [
- "/dev/null", "/dev/full", "/dev/zero",
- "/dev/random", "/dev/urandom",
- "/dev/ptmx", "/dev/kvm", "/dev/kqemu",
- "/dev/rtc", "/dev/hpet", "/dev/net/tun",
- "/dev/<my-vhost-device>",
- "/dev/hugepages"]
- ```
-
- <my-vhost-device> refers to "vhost-net" if using the `/dev/vhost-net`
- device. If you have specificed a different name in the database
- using the "other_config:cuse-dev-name" parameter, please specify that
- filename instead.
-
- 2. Disable SELinux or set to permissive mode
-
- 3. Restart the libvirtd process
- For example, on Fedora:
-
- `systemctl restart libvirtd.service`
-
- After successfully editing the configuration, you may launch your
- vhost-enabled VM. The XML describing the VM can be configured like so
- within the <qemu:commandline> section:
-
- 1. Set up shared hugepages:
-
- ```
- <qemu:arg value='-object'/>
- <qemu:arg value='memory-backend-file,id=mem,size=4096M,mem-path=/dev/hugepages,share=on'/>
- <qemu:arg value='-numa'/>
- <qemu:arg value='node,memdev=mem'/>
- <qemu:arg value='-mem-prealloc'/>
- ```
-
- 2. Set up your tap devices:
-
- ```
- <qemu:arg value='-netdev'/>
- <qemu:arg value='type=tap,id=net1,script=no,downscript=no,ifname=vhost0,vhost=on'/>
- <qemu:arg value='-device'/>
- <qemu:arg value='virtio-net-pci,netdev=net1,mac=00:00:00:00:00:01'/>
- ```
-
- Repeat for as many devices as are desired, modifying the id, ifname
- and mac as necessary.
-
- Again, if you are using an alternative character device (other than
- `/dev/vhost-net`), please specify the file descriptor like so:
-
- `<qemu:arg value='type=tap,id=net3,script=no,downscript=no,ifname=vhost0,vhost=on,vhostfd=<open_fd>'/>`
-
- Where <open_fd> refers to the open file descriptor of the character device.
- Instructions of how to retrieve the file descriptor can be found in the
- "DPDK vhost VM configuration" section.
- Alternatively, the process is automated with the qemu-wrap.py script,
- detailed in the next section.
-
- Now you may launch your VM using virt-manager, or like so:
-
- `virsh create my_vhost_vm.xml`
-
- - VM Configuration with libvirt & QEMU wrapper
-
- To use the qemu-wrapper script in conjuntion with libvirt, follow the
- steps in the previous section before proceeding with the following steps:
-
- 1. Place `qemu-wrap.py` in libvirtd binary search PATH ($PATH)
- Ideally in the same directory that the QEMU binary is located.
-
- 2. Ensure that the script has the same owner/group and file permissions
- as the QEMU binary.
-
- 3. Update the VM xml file using "virsh edit VM.xml"
-
- Set the VM to use the launch script.
- Set the emulator path contained in the `<emulator><emulator/>` tags.
- For example, replace `<emulator>/usr/bin/qemu-kvm<emulator/>` with
- `<emulator>/usr/bin/qemu-wrap.py<emulator/>`
-
- 4. Edit the Configuration Parameters section of the script to point to
- the correct emulator location and set any additional options. If you are
- using a alternative character device name, please set "us_vhost_path" to the
- location of that device. The script will automatically detect and insert
- the correct "vhostfd" value in the QEMU command line arguments.
-
- 5. Use virt-manager to launch the VM
-
### 6.3 DPDK backend inside VM
Please note that additional configuration is required if you want to run
* Support for DPDK 16.07
* Optional support for DPDK pdump enabled.
* Jumbo frame support
+ * Remove dpdkvhostcuse port type.
- Increase number of registers to 16.
- ovs-benchmark: This utility has been removed due to lack of use and
bitrot.
LDFLAGS="$LDFLAGS -L${DPDK_LIB_DIR}"
fi
- AC_COMPILE_IFELSE([
- AC_LANG_PROGRAM(
- [
- #include <rte_config.h>
-#if !RTE_LIBRTE_VHOST_USER
-#error
-#endif
- ], [])
- ], [],
- [AC_DEFINE([VHOST_CUSE], [1], [DPDK vhost-cuse support enabled, vhost-user disabled.])
- DPDK_EXTRA_LIB="-lfuse"])
-
AC_COMPILE_IFELSE([
AC_LANG_PROGRAM(
[
#define OVS_VHOST_QUEUE_DISABLED (-2) /* Queue was disabled by guest and not
* yet mapped to another queue. */
-#ifdef VHOST_CUSE
-static char *cuse_dev_name = NULL; /* Character device cuse_dev_name. */
-#endif
static char *vhost_sock_dir = NULL; /* Location of vhost-user sockets */
#define VHOST_ENQ_RETRY_NUM 8
}
}
-static int
-vhost_construct_helper(struct netdev *netdev) OVS_REQUIRES(dpdk_mutex)
-{
- if (rte_eal_init_ret) {
- return rte_eal_init_ret;
- }
-
- return netdev_dpdk_init(netdev, -1, DPDK_DEV_VHOST);
-}
-
-static int
-netdev_dpdk_vhost_cuse_construct(struct netdev *netdev)
-{
- struct netdev_dpdk *dev = netdev_dpdk_cast(netdev);
- int err;
-
- if (rte_eal_init_ret) {
- return rte_eal_init_ret;
- }
-
- ovs_mutex_lock(&dpdk_mutex);
- strncpy(CONST_CAST(char *, dev->vhost_id), netdev->name,
- sizeof dev->vhost_id);
- err = vhost_construct_helper(netdev);
- ovs_mutex_unlock(&dpdk_mutex);
- return err;
-}
-
static int
netdev_dpdk_vhost_user_construct(struct netdev *netdev)
{
fatal_signal_add_file_to_unlink(dev->vhost_id);
VLOG_INFO("Socket %s created for vhost-user port %s\n",
dev->vhost_id, name);
- err = vhost_construct_helper(netdev);
+ err = netdev_dpdk_init(netdev, -1, DPDK_DEV_VHOST);
}
ovs_mutex_unlock(&dpdk_mutex);
start_vhost_loop(void *dummy OVS_UNUSED)
{
pthread_detach(pthread_self());
- /* Put the cuse thread into quiescent state. */
+ /* Put the vhost thread into quiescent state. */
ovsrcu_quiesce_start();
rte_vhost_driver_session_start();
return NULL;
return 0;
}
-static int
-dpdk_vhost_cuse_class_init(void)
-{
- return 0;
-}
-
static int
dpdk_vhost_user_class_init(void)
{
return 0;
}
-static int
-netdev_dpdk_vhost_cuse_reconfigure(struct netdev *netdev)
-{
- struct netdev_dpdk *dev = netdev_dpdk_cast(netdev);
-
- ovs_mutex_lock(&dpdk_mutex);
- ovs_mutex_lock(&dev->mutex);
-
- netdev->n_txq = dev->requested_n_txq;
- netdev->n_rxq = 1;
-
- if (dev->requested_mtu != dev->mtu) {
- if (!netdev_dpdk_mempool_configure(dev)) {
- netdev_change_seq_changed(netdev);
- }
- }
-
- ovs_mutex_unlock(&dev->mutex);
- ovs_mutex_unlock(&dpdk_mutex);
-
- return 0;
-}
-
#define NETDEV_DPDK_CLASS(NAME, INIT, CONSTRUCT, DESTRUCT, \
SET_CONFIG, SET_TX_MULTIQ, SEND, \
GET_CARRIER, GET_STATS, \
val = smap_get(ovs_other_config, flag);
- /* Depending on which version of vhost is in use, process the vhost-specific
- * flag if it is provided, otherwise resort to default value.
+ /* Process the vhost-sock-dir flag if it is provided, otherwise resort to
+ * default value.
*/
if (val && (strlen(val) <= size)) {
changed = 1;
bool auto_determine = true;
int err = 0;
cpu_set_t cpuset;
-#ifndef VHOST_CUSE
char *sock_dir_subcomponent;
-#endif
if (!smap_get_bool(ovs_other_config, "dpdk-init", false)) {
VLOG_INFO("DPDK Disabled - to change this requires a restart.\n");
}
VLOG_INFO("DPDK Enabled, initializing");
-
-#ifdef VHOST_CUSE
- if (process_vhost_flags("cuse-dev-name", xstrdup("vhost-net"),
- PATH_MAX, ovs_other_config, &cuse_dev_name)) {
-#else
if (process_vhost_flags("vhost-sock-dir", xstrdup(ovs_rundir()),
NAME_MAX, ovs_other_config,
&sock_dir_subcomponent)) {
free(sock_dir_subcomponent);
} else {
vhost_sock_dir = sock_dir_subcomponent;
-#endif
}
argv = grow_argv(&argv, 0, 1);
ovs_thread_create("dpdk_watchdog", dpdk_watchdog, NULL);
-#ifdef VHOST_CUSE
- /* Register CUSE device to handle IOCTLs.
- * Unless otherwise specified, cuse_dev_name is set to vhost-net.
- */
- err = rte_vhost_driver_register(cuse_dev_name, 0);
-
- if (err != 0) {
- VLOG_ERR("CUSE device setup failure.");
- return;
- }
-#endif
-
dpdk_vhost_class_init();
#ifdef DPDK_PDUMP
netdev_dpdk_reconfigure,
netdev_dpdk_rxq_recv);
-static const struct netdev_class OVS_UNUSED dpdk_vhost_cuse_class =
- NETDEV_DPDK_CLASS(
- "dpdkvhostcuse",
- dpdk_vhost_cuse_class_init,
- netdev_dpdk_vhost_cuse_construct,
- netdev_dpdk_vhost_destruct,
- NULL,
- NULL,
- netdev_dpdk_vhost_send,
- netdev_dpdk_vhost_get_carrier,
- netdev_dpdk_vhost_get_stats,
- NULL,
- NULL,
- netdev_dpdk_vhost_cuse_reconfigure,
- netdev_dpdk_vhost_rxq_recv);
-
-static const struct netdev_class OVS_UNUSED dpdk_vhost_user_class =
+static const struct netdev_class dpdk_vhost_user_class =
NETDEV_DPDK_CLASS(
"dpdkvhostuser",
dpdk_vhost_user_class_init,
dpdk_common_init();
netdev_register_provider(&dpdk_class);
netdev_register_provider(&dpdk_ring_class);
-#ifdef VHOST_CUSE
- netdev_register_provider(&dpdk_vhost_cuse_class);
-#else
netdev_register_provider(&dpdk_vhost_user_class);
-#endif
}
void
* "OVSDPDKRPort", if <name> is a DPDK ring port (name must
start with dpdkr and end with portid, eg "dpdkr0")
- * "OVSDPDKVhostPort" if <name> is a DPDK vhost-cuse port
-
* "OVSDPDKVhostUserPort" if <name> is a DPDK vhost-user port
* "OVSDPDKBond" if <name> is an OVS DPDK bond.
-- add-port "$OVS_BRIDGE" "$DEVICE" $OVS_OPTIONS \
-- set Interface "$DEVICE" type=dpdkr ${OVS_EXTRA+-- $OVS_EXTRA}
;;
- OVSDPDVhostPort)
- ifup_ovs_bridge
- ovs-vsctl -t ${TIMEOUT} \
- -- --if-exists del-port "$OVS_BRIDGE" "$DEVICE" \
- -- add-port "$OVS_BRIDGE" "$DEVICE" $OVS_OPTIONS \
- -- set Interface "$DEVICE" type=dpdkvhost ${OVS_EXTRA+-- $OVS_EXTRA}
- ;;
OVSDPDKVhostUserPort)
ifup_ovs_bridge
ovs-vsctl -t ${TIMEOUT} \
utilities/ovs-test.in \
utilities/ovs-vlan-test.in \
utilities/ovs-vsctl-bashcomp.bash \
- utilities/qemu-wrap.py \
utilities/checkpatch.py
MAN_ROOTS += \
utilities/ovs-appctl.8.in \
+++ /dev/null
-#! /usr/bin/env python
-#
-# BSD LICENSE
-#
-# Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
-# All rights reserved.
-#
-# Redistribution and use in source and binary forms, with or without
-# modification, are permitted provided that the following conditions
-# are met:
-#
-# * Redistributions of source code must retain the above copyright
-# notice, this list of conditions and the following disclaimer.
-# * Redistributions in binary form must reproduce the above copyright
-# notice, this list of conditions and the following disclaimer in
-# the documentation and/or other materials provided with the
-# distribution.
-# * Neither the name of Intel Corporation nor the names of its
-# contributors may be used to endorse or promote products derived
-# from this software without specific prior written permission.
-#
-# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-#
-
-#####################################################################
-# This script is designed to modify the call to the QEMU emulator
-# to support userspace vhost when starting a guest machine through
-# libvirt with vhost enabled. The steps to enable this are as follows
-# and should be run as root:
-#
-# 1. Place this script in a libvirtd's binary search PATH ($PATH)
-# A good location would be in the same directory that the QEMU
-# binary is located
-#
-# 2. Ensure that the script has the same owner/group and file
-# permissions as the QEMU binary
-#
-# 3. Update the VM xml file using "virsh edit VM.xml"
-#
-# 3.a) Set the VM to use the launch script
-#
-# Set the emulator path contained in the
-# <emulator><emulator/> tags
-#
-# e.g replace <emulator>/usr/bin/qemu-kvm<emulator/>
-# with <emulator>/usr/bin/qemu-wrap.py<emulator/>
-#
-# 3.b) Set the VM's device's to use vhost-net offload
-#
-# <interface type="network">
-# <model type="virtio"/>
-# <driver name="vhost"/>
-# <interface/>
-#
-# 4. Enable libvirt to access our userpace device file by adding it to
-# controllers cgroup for libvirtd using the following steps
-#
-# 4.a) In /etc/libvirt/qemu.conf add/edit the following lines:
-# 1) cgroup_controllers = [ ... "devices", ... ]
-# 2) clear_emulator_capabilities = 0
-# 3) user = "root"
-# 4) group = "root"
-# 5) cgroup_device_acl = [
-# "/dev/null", "/dev/full", "/dev/zero",
-# "/dev/random", "/dev/urandom",
-# "/dev/ptmx", "/dev/kvm", "/dev/kqemu",
-# "/dev/rtc", "/dev/hpet", "/dev/net/tun",
-# "/dev/<devbase-name>-<index>",
-# "/dev/hugepages"
-# ]
-#
-# 4.b) Disable SELinux or set to permissive mode
-#
-# 4.c) Mount cgroup device controller
-# "mkdir /dev/cgroup"
-# "mount -t cgroup none /dev/cgroup -o devices"
-#
-# 4.d) Set hugetlbfs_mount variable - ( Optional )
-# VMs using userspace vhost must use hugepage backed
-# memory. This can be enabled in the libvirt XML
-# config by adding a memory backing section to the
-# XML config e.g.
-# <memoryBacking>
-# <hugepages/>
-# </memoryBacking>
-# This memory backing section should be added after the
-# <memory> and <currentMemory> sections. This will add
-# flags "-mem-prealloc -mem-path <path>" to the QEMU
-# command line. The hugetlbfs_mount variable can be used
-# to override the default <path> passed through by libvirt.
-#
-# if "-mem-prealloc" or "-mem-path <path>" are not passed
-# through and a vhost device is detected then these options will
-# be automatically added by this script. This script will detect
-# the system hugetlbfs mount point to be used for <path>. The
-# default <path> for this script can be overidden by the
-# hugetlbfs_dir variable in the configuration section of this script.
-#
-#
-# 4.e) Restart the libvirtd system process
-# e.g. on Fedora "systemctl restart libvirtd.service"
-#
-#
-# 4.f) Edit the Configuration Parameters section of this script
-# to point to the correct emulator location and set any
-# addition options
-#
-# The script modifies the libvirtd Qemu call by modifying/adding
-# options based on the configuration parameters below.
-# NOTE:
-# emul_path and us_vhost_path must be set
-# All other parameters are optional
-#####################################################################
-
-
-#############################################
-# Configuration Parameters
-#############################################
-#Path to QEMU binary
-emul_path = "/usr/local/bin/qemu-system-x86_64"
-
-#Path to userspace vhost device file
-# This filename should match the --dev-basename --dev-index parameters of
-# the command used to launch the userspace vhost sample application e.g.
-# if the sample app lauch command is:
-# ./build/vhost-switch ..... --dev-basename usvhost --dev-index 1
-# then this variable should be set to:
-# us_vhost_path = "/dev/usvhost-1"
-us_vhost_path = "/dev/usvhost-1"
-
-#List of additional user defined emulation options. These options will
-#be added to all Qemu calls
-emul_opts_user = []
-
-#List of additional user defined emulation options for vhost only.
-#These options will only be added to vhost enabled guests
-emul_opts_user_vhost = []
-
-#For all VHOST enabled VMs, the VM memory is preallocated from hugetlbfs
-# Set this variable to one to enable this option for all VMs
-use_huge_all = 0
-
-#Instead of autodetecting, override the hugetlbfs directory by setting
-#this variable
-hugetlbfs_dir = ""
-
-#############################################
-
-
-#############################################
-# ****** Do Not Modify Below this Line ******
-#############################################
-
-import sys, os, subprocess
-import time
-import signal
-
-
-#List of open userspace vhost file descriptors
-fd_list = []
-
-#additional virtio device flags when using userspace vhost
-vhost_flags = [ "csum=off",
- "gso=off",
- "guest_tso4=off",
- "guest_tso6=off",
- "guest_ecn=off"
- ]
-
-#String of the path to the Qemu process pid
-qemu_pid = "/tmp/%d-qemu.pid" % os.getpid()
-
-#############################################
-# Signal haldler to kill Qemu subprocess
-#############################################
-def kill_qemu_process(signum, stack):
- pidfile = open(qemu_pid, 'r')
- pid = int(pidfile.read())
- os.killpg(pid, signal.SIGTERM)
- pidfile.close()
-
-
-#############################################
-# Find the system hugefile mount point.
-# Note:
-# if multiple hugetlbfs mount points exist
-# then the first one found will be used
-#############################################
-def find_huge_mount():
-
- if (len(hugetlbfs_dir)):
- return hugetlbfs_dir
-
- huge_mount = ""
-
- if (os.access("/proc/mounts", os.F_OK)):
- f = open("/proc/mounts", "r")
- line = f.readline()
- while line:
- line_split = line.split(" ")
- if line_split[2] == 'hugetlbfs':
- huge_mount = line_split[1]
- break
- line = f.readline()
- else:
- print "/proc/mounts not found"
- exit (1)
-
- f.close
- if len(huge_mount) == 0:
- print "Failed to find hugetlbfs mount point"
- exit (1)
-
- return huge_mount
-
-
-#############################################
-# Get a userspace Vhost file descriptor
-#############################################
-def get_vhost_fd():
-
- if (os.access(us_vhost_path, os.F_OK)):
- fd = os.open( us_vhost_path, os.O_RDWR)
- else:
- print ("US-Vhost file %s not found" %us_vhost_path)
- exit (1)
-
- return fd
-
-
-#############################################
-# Check for vhostfd. if found then replace
-# with our own vhost fd and append any vhost
-# flags onto the end
-#############################################
-def modify_netdev_arg(arg):
-
- global fd_list
- vhost_in_use = 0
- s = ''
- new_opts = []
- netdev_opts = arg.split(",")
-
- for opt in netdev_opts:
- #check if vhost is used
- if "vhost" == opt[:5]:
- vhost_in_use = 1
- else:
- new_opts.append(opt)
-
- #if using vhost append vhost options
- if vhost_in_use == 1:
- #append vhost on option
- new_opts.append('vhost=on')
- #append vhostfd ption
- new_fd = get_vhost_fd()
- new_opts.append('vhostfd=' + str(new_fd))
- fd_list.append(new_fd)
-
- #concatenate all options
- for opt in new_opts:
- if len(s) > 0:
- s+=','
-
- s+=opt
-
- return s
-
-
-#############################################
-# Main
-#############################################
-def main():
-
- global fd_list
- global vhost_in_use
- new_args = []
- num_cmd_args = len(sys.argv)
- emul_call = ''
- mem_prealloc_set = 0
- mem_path_set = 0
- num = 0;
-
- #parse the parameters
- while (num < num_cmd_args):
- arg = sys.argv[num]
-
- #Check netdev +1 parameter for vhostfd
- if arg == '-netdev':
- num_vhost_devs = len(fd_list)
- new_args.append(arg)
-
- num+=1
- arg = sys.argv[num]
- mod_arg = modify_netdev_arg(arg)
- new_args.append(mod_arg)
-
- #append vhost flags if this is a vhost device
- # and -device is the next arg
- # i.e -device -opt1,-opt2,...,-opt3,%vhost
- if (num_vhost_devs < len(fd_list)):
- num+=1
- arg = sys.argv[num]
- if arg == '-device':
- new_args.append(arg)
- num+=1
- new_arg = sys.argv[num]
- for flag in vhost_flags:
- new_arg = ''.join([new_arg,',',flag])
- new_args.append(new_arg)
- else:
- new_args.append(arg)
- elif arg == '-mem-prealloc':
- mem_prealloc_set = 1
- new_args.append(arg)
- elif arg == '-mem-path':
- mem_path_set = 1
- new_args.append(arg)
-
- else:
- new_args.append(arg)
-
- num+=1
-
- #Set Qemu binary location
- emul_call+=emul_path
- emul_call+=" "
-
- #Add prealloc mem options if using vhost and not already added
- if ((len(fd_list) > 0) and (mem_prealloc_set == 0)):
- emul_call += "-mem-prealloc "
-
- #Add mempath mem options if using vhost and not already added
- if ((len(fd_list) > 0) and (mem_path_set == 0)):
- #Detect and add hugetlbfs mount point
- mp = find_huge_mount()
- mp = "".join(["-mem-path ", mp])
- emul_call += mp
- emul_call += " "
-
- #add user options
- for opt in emul_opts_user:
- emul_call += opt
- emul_call += " "
-
- #Add add user vhost only options
- if len(fd_list) > 0:
- for opt in emul_opts_user_vhost:
- emul_call += opt
- emul_call += " "
-
- #Add updated libvirt options
- iter_args = iter(new_args)
- #skip 1st arg i.e. call to this script
- next(iter_args)
- for arg in iter_args:
- emul_call+=str(arg)
- emul_call+= " "
-
- emul_call += "-pidfile %s " % qemu_pid
- #Call QEMU
- process = subprocess.Popen(emul_call, shell=True, preexec_fn=os.setsid)
-
- for sig in [signal.SIGTERM, signal.SIGINT, signal.SIGHUP, signal.SIGQUIT]:
- signal.signal(sig, kill_qemu_process)
-
- process.wait()
-
- #Close usvhost files
- for fd in fd_list:
- os.close(fd)
- #Cleanup temporary files
- if os.access(qemu_pid, os.F_OK):
- os.remove(qemu_pid)
-
-
-
-if __name__ == "__main__":
- main()
</p>
</column>
- <column name="other_config" key="cuse-dev-name"
- type='{"type": "string"}'>
- <p>
- Specifies the name of the vhost-cuse character device to open for
- vhost-cuse support.
- </p>
- <p>
- The default is vhost-net. Changing this value requires restarting
- the daemon.
- </p>
- </column>
-
<column name="other_config" key="vhost-sock-dir"
type='{"type": "string"}'>
<p>