netdev-dpdk: Convert initialization from cmdline to db

Existing DPDK integration is provided by use of command line options which
must be split out and passed to librte in a special manner. However, this
forces any configuration to be passed by way of a special DPDK flag, and
interferes with ovs+dpdk packaging solutions.

This commit delays dpdk initialization until after the OVS database
connection is established, at which point ovs initializes librte. It
pulls all of the config data from the OVS database, and assembles a
new argv/argc pair to be passed along.

Signed-off-by: Aaron Conole <[email protected]>
Acked-by: Kevin Traynor <[email protected]>
Acked-by: Daniele Di Proietto <[email protected]>

FAQ.md

@@ -445,9 +445,9 @@ A: Yes.  How you configure it depends on what you mean by "promiscuous
 
 A: Firstly, you must have a DPDK-enabled version of Open vSwitch.
 
-   If your version is DPDK-enabled it will support the --dpdk
-   argument on the command line and will display lines with
-   "EAL:..." during startup when --dpdk is supplied.
+   If your version is DPDK-enabled it will support the other-config:dpdk-init
+   configuration in the database and will display lines with "EAL:..."
+   during startup when other_config:dpdk-init is set to 'true'.
 
    Secondly, when adding a DPDK port, unlike a system port, the
    type for the interface must be specified. For example;

INSTALL.DPDK.md

@@ -138,22 +138,62 @@ Using the DPDK with ovs-vswitchd:
 
 5. Start vswitchd:
 
-   DPDK configuration arguments can be passed to vswitchd via `--dpdk`
-   argument. This needs to be first argument passed to vswitchd process.
-   dpdk arg -c is ignored by ovs-dpdk, but it is a required parameter
-   for dpdk initialization.
+   DPDK configuration arguments can be passed to vswitchd via Open_vSwitch
+   other_config column. The recognized configuration options are listed.
+   Defaults will be provided for all values not explicitly set.
+
+   * dpdk-init
+   Specifies whether OVS should initialize and support DPDK ports. This is
+   a boolean, and defaults to false.
+
+   * dpdk-lcore-mask
+   Specifies the CPU cores on which dpdk lcore threads should be spawned.
+   The DPDK lcore threads are used for DPDK library tasks, such as
+   library internal message processing, logging, etc. Value should be in
+   the form of a hex string (so '0x123') similar to the 'taskset' mask
+   input.
+   If not specified, the value will be determined by choosing the lowest
+   CPU core from initial cpu affinity list. Otherwise, the value will be
+   passed directly to the DPDK library.
+   For performance reasons, it is best to set this to a single core on
+   the system, rather than allow lcore threads to float.
+
+   * dpdk-alloc-mem
+   This sets the total memory to preallocate from hugepages regardless of
+   processor socket. It is recommended to use dpdk-socket-mem instead.
+
+   * dpdk-socket-mem
+   Comma separated list of memory to pre-allocate from hugepages on specific
+   sockets.
+
+   * dpdk-hugepage-dir
+   Directory where hugetlbfs is mounted
+
+   * cuse-dev-name
+   Option to set the vhost_cuse character device name.
+
+   * vhost-sock-dir
+   Option to set the path to the vhost_user unix socket files.
+
+   NOTE: Changing any of these options requires restarting the ovs-vswitchd
+   application.
+
+   Open vSwitch can be started as normal. DPDK will be initialized as long
+   as the dpdk-init option has been set to 'true'.
+
 
    ```
    export DB_SOCK=/usr/local/var/run/openvswitch/db.sock
-   ovs-vswitchd --dpdk -c 0x1 -n 4 -- unix:$DB_SOCK --pidfile --detach
+   ovs-vsctl --no-wait set Open_vSwitch . other_config:dpdk-init=true
+   ovs-vswitchd unix:$DB_SOCK --pidfile --detach
    ```
 
    If allocated more than one GB hugepage (as for IVSHMEM), set amount and
    use NUMA node 0 memory:
 
    ```
-   ovs-vswitchd --dpdk -c 0x1 -n 4 --socket-mem 1024,0 \
-   -- unix:$DB_SOCK --pidfile --detach
+   ovs-vsctl --no-wait set Open_vSwitch . other_config:dpdk-socket-mem="1024,0"
+   ovs-vswitchd unix:$DB_SOCK --pidfile --detach
    ```
 
 6. Add bridge & ports
@@ -540,11 +580,12 @@ in the names.
      `/usr/local/var/run/openvswitch/vhost-user-1`, which you must provide
      to your VM on the QEMU command line. More instructions on this can be
      found in the next section "DPDK vhost-user VM configuration"
-     Note: If you wish for the vhost-user sockets to be created in a
-     directory other than `/usr/local/var/run/openvswitch`, you may specify
-     another location on the ovs-vswitchd command line like so:
+  - If you wish for the vhost-user sockets to be created in a directory other
+    than `/usr/local/var/run/openvswitch`, you may specify another location
+    in the ovsdb like so:
 
-      `./vswitchd/ovs-vswitchd --dpdk -vhost_sock_dir /my-dir -c 0x1 ...`
+      `./utilities/ovs-vsctl --no-wait \
+        set Open_vSwitch . other_config:vhost-sock-dir=path`
 
 DPDK vhost-user VM configuration:
 ---------------------------------
@@ -692,14 +733,13 @@ DPDK vhost-cuse VM configuration:
 
 1. This step is only needed if using an alternative character device.
 
-   The new character device filename must be specified on the vswitchd
-   commandline:
+   The new character device filename must be specified in the ovsdb:
 
-        `./vswitchd/ovs-vswitchd --dpdk --cuse_dev_name my-vhost-net -c 0x1 ...`
+        `./utilities/ovs-vsctl --no-wait set Open_vSwitch . \
+                          other_config:cuse-dev-name=my-vhost-net`
 
-   Note that the `--cuse_dev_name` argument and associated string must be the first
-   arguments after `--dpdk` and come before the EAL arguments. In the example
-   above, the character device to be used will be `/dev/my-vhost-net`.
+   In the example above, the character device to be used will be
+   `/dev/my-vhost-net`.
 
 2. This step is only needed if reusing the standard character device. It will
    conflict with the kernel vhost character device so the user must first
@@ -811,8 +851,8 @@ steps.
         ```
 
         <my-vhost-device> refers to "vhost-net" if using the `/dev/vhost-net`
-        device. If you have specificed a different name on the ovs-vswitchd
-        commandline using the "--cuse_dev_name" parameter, please specify that
+        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

NEWS

@@ -26,6 +26,11 @@ Post-v2.5.0
        assignment.
      * Type of log messages from PMD threads changed from INFO to DBG.
      * QoS functionality with sample egress-policer implementation.
+     * The mechanism for configuring DPDK has changed to use database
+     * Sensible defaults have been introduced for many of the required
+       configuration options
+     * DB entries have been added for many of the DPDK EAL command line
+       arguments
    - ovs-benchmark: This utility has been removed due to lack of use and
      bitrot.
    - ovs-appctl:

lib/automake.mk

@@ -354,6 +354,10 @@ if DPDK_NETDEV
 lib_libopenvswitch_la_SOURCES += \
        lib/netdev-dpdk.c \
        lib/netdev-dpdk.h
+else
+lib_libopenvswitch_la_SOURCES += \
+	lib/netdev-nodpdk.c \
+	lib/netdev-dpdk.h
 endif
 
 if WIN32