dpdk: reflect status and version in the database

The normal way of retrieving the running DPDK status involves parsing
log files and issuing various incantations of ovs-vsctl and ovs-appctl
commands to determine whether the rte_eal_init successfully started.

This commit adds two new records to reflect the dpdk version, and
the dpdk initialization status.

To support this, the other_config:dpdk-init configuration block supports
the 'true' and 'try' keywords now, instead of just 'true'.

Signed-off-by: Aaron Conole <aconole@redhat.com>
Acked-by: Kevin Traynor <ktraynor@redhat.com>
Signed-off-by: Ian Stokes <ian.stokes@intel.com>

Documentation/faq/configuration.rst

@@ -102,9 +102,11 @@ Q: How do I configure a DPDK port as an access port?
 
     A: Firstly, you must have a DPDK-enabled version of Open vSwitch.
 
-    If your version is DPDK-enabled it will support the other-config:dpdk-init
+    If your version is DPDK-enabled it may support the dpdk_version and
-    configuration in the database and will display lines with "EAL:..." during
+    dpdk_initialized keys in the configuration database.  Earlier versions
-    startup when other_config:dpdk-init is set to 'true'.
+    of Open vSwitch only supported the other-config:dpdk-init key in the
+    configuration in the database.  All versions 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 and valid dpdk-devargs must be specified. For example::

Documentation/intro/install/dpdk.rst

@@ -208,7 +208,8 @@ Open vSwitch should be started as described in :doc:`general` with the
 exception of ovs-vswitchd, which requires some special configuration to enable
 DPDK functionality. DPDK configuration arguments can be passed to ovs-vswitchd
 via the ``other_config`` column of the ``Open_vSwitch`` table. At a minimum,
-the ``dpdk-init`` option must be set to ``true``. For example::
+the ``dpdk-init`` option must be set to either ``true`` or ``try``.
+For example::
 
     $ export PATH=$PATH:/usr/local/share/openvswitch/scripts
     $ export DB_SOCK=/usr/local/var/run/openvswitch/db.sock
@@ -219,8 +220,12 @@ There are many other configuration options, the most important of which are
 listed below. Defaults will be provided for all values not explicitly set.
 
 ``dpdk-init``
-  Specifies whether OVS should initialize and support DPDK ports. This is a
+  Specifies whether OVS should initialize and support DPDK ports. This field
-  boolean, and defaults to false.
+  can either be ``true`` or ``try``.
+  A value of ``true`` will cause the ovs-vswitchd process to abort on
+  initialization failure.
+  A value of ``try`` will imply that the ovs-vswitchd process should
+  continue running even if the EAL initialization fails.
 
 ``dpdk-lcore-mask``
   Specifies the CPU cores on which dpdk lcore threads should be spawned and
@@ -257,6 +262,22 @@ See the section ``Performance Tuning`` for important DPDK customizations.
 Validating
 ----------
 
+DPDK support can be confirmed by validating the ``dpdk_initialized`` boolean
+value from the ovsdb.  A value of ``true`` means that the DPDK EAL
+initialization succeeded::
+
+  $ ovs-vsctl get Open_vSwitch . dpdk_initialized
+  true
+
+Additionally, the library version linked to ovs-vswitchd can be confirmed
+with either the ovs-vswitchd logs, or by running either of the commands::
+
+  $ ovs-vswitchd --version
+  ovs-vswitchd (Open vSwitch) 2.9.0
+  DPDK 17.11.0
+  $ ovs-vsctl get Open_vSwitch . dpdk_version
+  "DPDK 17.11.0"
+
 At this point you can use ovs-vsctl to set up bridges and other Open vSwitch
 features. Seeing as we've configured the DPDK datapath, we will use DPDK-type
 ports. For example, to create a userspace bridge named ``br0`` and add two

NEWS

@@ -30,6 +30,7 @@ Post-v2.9.0
      * New 'check-dpdk' Makefile target to run a new system testsuite.
        See Testing topic for the details.
      * Add LSC interrupt support for DPDK physical devices.
+     * Allow init to fail and record DPDK status/version in OVS database.
    - Userspace datapath:
      * Commands ovs-appctl dpif-netdev/pmd-*-show can now work on a single PMD
      * Detailed PMD performance metrics available with new command

lib/dpdk-stub.c

@@ -21,6 +21,7 @@
 #include "smap.h"
 #include "ovs-thread.h"
 #include "openvswitch/vlog.h"
+#include "vswitch-idl.h"
 
 VLOG_DEFINE_THIS_MODULE(dpdk);
 
@@ -59,3 +60,12 @@ void
 print_dpdk_version(void)
 {
 }
+
+void
+dpdk_status(const struct ovsrec_open_vswitch *cfg)
+{
+    if (cfg) {
+        ovsrec_open_vswitch_set_dpdk_initialized(cfg, false);
+        ovsrec_open_vswitch_set_dpdk_version(cfg, "none");
+    }
+}

lib/dpdk.c

@@ -37,6 +37,7 @@
 #include "openvswitch/dynamic-string.h"
 #include "openvswitch/vlog.h"
 #include "smap.h"
+#include "vswitch-idl.h"
 
 VLOG_DEFINE_THIS_MODULE(dpdk);
 
@@ -44,6 +45,8 @@ static FILE *log_stream = NULL;       /* Stream for DPDK log redirection */
 
 static char *vhost_sock_dir = NULL;   /* Location of vhost-user sockets */
 static bool vhost_iommu_enabled = false; /* Status of vHost IOMMU support */
+static bool dpdk_initialized = false; /* Indicates successful initialization
+                                       * of DPDK. */
 
 static int
 process_vhost_flags(char *flag, const char *default_val, int size,
@@ -474,7 +477,11 @@ dpdk_init(const struct smap *ovs_other_config)
         return;
     }
 
-    if (smap_get_bool(ovs_other_config, "dpdk-init", false)) {
+    const char *dpdk_init_val = smap_get_def(ovs_other_config, "dpdk-init",
+                                             "false");
+
+    bool try_only = !strcmp(dpdk_init_val, "try");
+    if (!strcmp(dpdk_init_val, "true") || try_only) {
         static struct ovsthread_once once_enable = OVSTHREAD_ONCE_INITIALIZER;
 
         if (ovsthread_once_start(&once_enable)) {
@@ -483,7 +490,7 @@ dpdk_init(const struct smap *ovs_other_config)
             enabled = dpdk_init__(ovs_other_config);
             if (enabled) {
                 VLOG_INFO("DPDK Enabled - initialized");
-            } else {
+            } else if (!try_only) {
                 ovs_abort(rte_errno, "Cannot init EAL");
             }
             ovsthread_once_done(&once_enable);
@@ -493,6 +500,7 @@ dpdk_init(const struct smap *ovs_other_config)
     } else {
         VLOG_INFO_ONCE("DPDK Disabled - Use other_config:dpdk-init to enable");
     }
+    dpdk_initialized = enabled;
 }
 
 const char *
@@ -520,3 +528,12 @@ print_dpdk_version(void)
 {
     puts(rte_version());
 }
+
+void
+dpdk_status(const struct ovsrec_open_vswitch *cfg)
+{
+    if (cfg) {
+        ovsrec_open_vswitch_set_dpdk_initialized(cfg, dpdk_initialized);
+        ovsrec_open_vswitch_set_dpdk_version(cfg, rte_version());
+    }
+}

lib/dpdk.h

@@ -33,11 +33,12 @@
 #endif /* DPDK_NETDEV */
 
 struct smap;
+struct ovsrec_open_vswitch;
 
 void dpdk_init(const struct smap *ovs_other_config);
 void dpdk_set_lcore_id(unsigned cpu);
 const char *dpdk_get_vhost_sock_dir(void);
 bool dpdk_vhost_iommu_enabled(void);
 void print_dpdk_version(void);
-
+void dpdk_status(const struct ovsrec_open_vswitch *);
 #endif /* dpdk.h */

vswitchd/bridge.c

@@ -407,6 +407,8 @@ bridge_init(const char *remote)
     ovsdb_idl_omit(idl, &ovsrec_open_vswitch_col_db_version);
     ovsdb_idl_omit(idl, &ovsrec_open_vswitch_col_system_type);
     ovsdb_idl_omit(idl, &ovsrec_open_vswitch_col_system_version);
+    ovsdb_idl_omit_alert(idl, &ovsrec_open_vswitch_col_dpdk_version);
+    ovsdb_idl_omit_alert(idl, &ovsrec_open_vswitch_col_dpdk_initialized);
 
     ovsdb_idl_omit_alert(idl, &ovsrec_bridge_col_datapath_id);
     ovsdb_idl_omit_alert(idl, &ovsrec_bridge_col_datapath_version);
@@ -2837,10 +2839,13 @@ run_status_update(void)
          * previous one is not done. */
         seq = seq_read(connectivity_seq_get());
         if (seq != connectivity_seqno || status_txn_try_again) {
+            const struct ovsrec_open_vswitch *cfg =
+                ovsrec_open_vswitch_first(idl);
             struct bridge *br;
 
             connectivity_seqno = seq;
             status_txn = ovsdb_idl_txn_create(idl);
+            dpdk_status(cfg);
             HMAP_FOR_EACH (br, node, &all_bridges) {
                 struct port *port;
 

vswitchd/vswitch.ovsschema

@@ -1,6 +1,6 @@
 {"name": "Open_vSwitch",
- "version": "7.15.1",
+ "version": "7.16.0",
- "cksum": "3682332033 23608",
+ "cksum": "2403910601 23776",
  "tables": {
    "Open_vSwitch": {
      "columns": {
@@ -47,7 +47,12 @@
                   "min": 0, "max": "unlimited"}},
        "iface_types": {
          "type": {"key": {"type": "string"},
-                  "min": 0, "max": "unlimited"}}},
+                  "min": 0, "max": "unlimited"}},
+       "dpdk_initialized": {
+         "type": "boolean"},
+       "dpdk_version": {
+         "type": {"key": {"type": "string"},
+                  "min": 0, "max": 1}}},
      "isRoot": true,
      "maxRows": 1},
    "Bridge": {

vswitchd/vswitch.xml

@@ -490,6 +490,11 @@
         configuration changes.
       </column>
 
+      <column name="dpdk_initialized">
+        True if <ref column="other_config" key="dpdk-init"/> is set to
+        true and the DPDK library is successfully initialized.
+      </column>
+
       <group title="Statistics">
         <p>
           The <code>statistics</code> column contains key-value pairs that
@@ -673,6 +678,12 @@
         </p>
       </column>
 
+      <column name="dpdk_version">
+        <p>
+          The version of the linked DPDK library.
+        </p>
+      </column>
+
     </group>
 
     <group title="Capabilities">