netdev-dpdk: Allow arbitrary eal arguments

A previous change moved some commonly used arguments from commandline to
the database, and with it the ability to pass arbitrary arguments to
EAL. This change allows arbitrary eal arguments to be provided
via a new db entry 'other_config:dpdk-extra' which will tokenize the
string and add it to the argument list. The only argument which will not
be supported with this change is '--no-huge', which appears to break the
system in other ways.

Signed-off-by: Aaron Conole <aconole@redhat.com>
Tested-by: Sean K Mooney <sean.k.mooney@intel.com>
Tested-by: RobertX Wojciechowicz <robertx.wojciechowicz@intel.com>
Tested-by: Kevin Traynor <kevin.traynor@intel.com>
Acked-by: Panu Matilainen <pmatilai@redhat.com>
Acked-by: Kevin Traynor <kevin.traynor@intel.com>
Acked-by: Flavio Leitner <fbl@sysclose.org>
Acked-by: Daniele Di Proietto <diproiettod@vmware.com>

INSTALL.DPDK.md

@@ -169,6 +169,11 @@ Using the DPDK with ovs-vswitchd:
    * dpdk-hugepage-dir
    Directory where hugetlbfs is mounted
 
+   * dpdk-extra
+   Extra arguments to provide to DPDK EAL, as previously specified on the
+   command line. Do not pass '--no-huge' to the system in this way. Support
+   for running the system without hugepages is nonexistent.
+
    * cuse-dev-name
    Option to set the vhost_cuse character device name.
 

NEWS

@@ -30,7 +30,8 @@ Post-v2.5.0
      * 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
+       arguments. Additional arguments can be passed via the dpdk-extra
+       entry.
    - ovs-benchmark: This utility has been removed due to lack of use and
      bitrot.
    - ovs-appctl:

lib/netdev-dpdk.c

@@ -39,6 +39,7 @@
 #include "netdev-provider.h"
 #include "netdev-vport.h"
 #include "odp-util.h"
+#include "openvswitch/dynamic-string.h"
 #include "openvswitch/list.h"
 #include "openvswitch/ofp-print.h"
 #include "openvswitch/vlog.h"
@@ -2772,6 +2773,23 @@ dpdk_option_extend(char ***argv, int argc, const char *option,
     newargv[argc+1] = xstrdup(value);
 }
 
+static int
+extra_dpdk_args(const char *ovs_extra_config, char ***argv, int argc)
+{
+    int ret = argc;
+    char *release_tok = xstrdup(ovs_extra_config);
+    char *tok = release_tok, *endptr = NULL;
+
+    for (tok = strtok_r(release_tok, " ", &endptr); tok != NULL;
+         tok = strtok_r(NULL, " ", &endptr)) {
+        char **newarg = grow_argv(argv, ret, 1);
+        *argv = newarg;
+        newarg[ret++] = xstrdup(tok);
+    }
+    free(release_tok);
+    return ret;
+}
+
 static int
 construct_dpdk_options(const struct smap *ovs_other_config,
                        char ***argv, const int initial_size)
@@ -2869,8 +2887,14 @@ static int
 get_dpdk_args(const struct smap *ovs_other_config, char ***argv,
               int argc)
 {
+    const char *extra_configuration;
     int i = construct_dpdk_options(ovs_other_config, argv, argc);
     i = construct_dpdk_mutex_options(ovs_other_config, argv, i);
+
+    extra_configuration = smap_get(ovs_other_config, "dpdk-extra");
+    if (extra_configuration) {
+        i = extra_dpdk_args(extra_configuration, argv, i);
+    }
     return i;
 }
 
@@ -2981,6 +3005,19 @@ dpdk_init__(const struct smap *ovs_other_config)
 
     optind = 1;
 
+    if (VLOG_IS_INFO_ENABLED()) {
+        struct ds eal_args;
+        int opt;
+        ds_init(&eal_args);
+        ds_put_cstr(&eal_args, "EAL ARGS:");
+        for (opt = 0; opt < argc; ++opt) {
+            ds_put_cstr(&eal_args, " ");
+            ds_put_cstr(&eal_args, argv[opt]);
+        }
+        VLOG_INFO("%s", ds_cstr_ro(&eal_args));
+        ds_destroy(&eal_args);
+    }
+
     /* Make sure things are initialized ... */
     result = rte_eal_init(argc, argv);
     if (result < 0) {

utilities/ovs-dev.py

@@ -267,6 +267,8 @@ def run():
     if options.dpdk:
         _sh("ovs-vsctl --no-wait set Open_vSwitch %s " \
             "other_config:dpdk-init=true" % root_uuid)
+        _sh("ovs-vsctl --no-wait set Open_vSwitch %s other_config:" \
+            "dpdk-extra=\"%s\"" % (root_uuid, ' '.join(options.dpdk)))
     else:
         _sh("ovs-vsctl --no-wait set Open_vSwitch %s " \
             "other_config:dpdk-init=false" % root_uuid)
@@ -423,8 +425,9 @@ def main():
                      help="run ovs-vswitchd under gdb")
     group.add_option("--valgrind", dest="valgrind", action="store_true",
                      help="run ovs-vswitchd under valgrind")
-    group.add_option("--dpdk", dest="dpdk", action="store_true",
-                     help="run ovs-vswitchd with dpdk")
+    group.add_option("--dpdk", dest="dpdk", action="callback",
+                     callback=parse_subargs,
+                     help="run ovs-vswitchd with dpdk subopts (ended by --)")
     group.add_option("--clang", dest="clang", action="store_true",
                      help="Use binaries built by clang")
     group.add_option("--user", dest="user", action="store", default="",

vswitchd/vswitch.xml

@@ -275,6 +275,17 @@
         </p>
       </column>
 
+      <column name="other_config" key="dpdk-extra"
+              type='{"type": "string"}'>
+        <p>
+          Specifies additional eal command line arguments for DPDK.
+        </p>
+        <p>
+          The default is empty. Changing this value requires restarting the
+          daemon
+        </p>
+      </column>
+
       <column name="other_config" key="cuse-dev-name"
               type='{"type": "string"}'>
         <p>