I did a bit of research and I found out what's happening here. Here's an OVS command for DPDK:
/home/ryan/ovs/_build-gcc/vswitchd/ovs-vswitchd --dpdk -c 0x1 -n 4 -- unix:/home/alex/root/run/db.sock --pidfile --log-file --enable-dummy -vconsole:off --detach What will happen when running with DPDK is rte_eal_init will count the following arguments "--dpdk -c 0x1 -n 4". Hence, we'll be left to parse the remaining command "-- unix:/home/alex/root/run/db.sock --pidfile --log-file --enable-dummy -vconsole:off --detach". Without DPDK, we'll have to parse "/home/ryan/ovs/_build-gcc/vswitchd/ovs-vswitchd unix:/home/alex/root/run/db.sock --pidfile --log-file --enable-dummy -vconsole:off --detach". Thus, the only difference is the first argument here "--" vs. "/home/ryan/ovs/_build-gcc/vswitchd/ovs-vswitchd". Basically, the code always skips by default the first of the remaining arguments. With DPDK, its "--" but without DPDK, its the program name. So dpdk_init() actually does skip the program name, I believe. Anyways it doesn't really matter as long as this works. Ryan On 6/19/14 2:14 PM, "Pravin Shelar" <pshe...@nicira.com> wrote: >On Wed, Jun 18, 2014 at 4:54 PM, Ryan Wilson 76511 <wr...@vmware.com> >wrote: >> Well we're really not 'skipping' the '--dpdk' argument since that is >> passed to rte_eal_init() as well. We're skipping the program name which >>is >> the path to ovs-vswitchd. I'd change the comment in the patch to >>something >> like: >> >Well it depends on individual perspective, but vswitchd program name >is present with or without dpdk parameter, so I think we are skipping >--dpdk. > >> diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c >> index fbdb6b3..5cd4a07 100644 >> --- a/lib/netdev-dpdk.c >> +++ b/lib/netdev-dpdk.c >> @@ -1193,7 +1193,8 @@ dpdk_init(int argc, char **argv) >> rte_memzone_dump(); >> rte_eal_init_ret = 0; >> >> - return result; >> + /* We need to skip 'result' arguments plus the program name itself >>*/ >> + return result + 1; >> } >> >> void >> >> >> Otherwise, LGTM. >> >> Acked-by: Ryan Wilson <wr...@nicira.com> >> >> Can someone else review this and if they have no qualms, push it? This >>is >> necessary for DPDK to work properly. >> >> >> On 6/16/14 9:46 AM, "Daniele Di Proietto" <ddiproie...@vmware.com> >>wrote: >> >>>rte_eal_init() returns the number of parsed dpdk arguments to skip. >>>dpdk_init() should add 1 to that number, because it has already skipped >>>the >>>"--dpdk" argument itself >>> >>>Signed-off-by: Daniele Di Proietto <ddiproie...@vmware.com> >>>--- >>> lib/netdev-dpdk.c | 3 ++- >>> 1 file changed, 2 insertions(+), 1 deletion(-) >>> >>>diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c >>>index fbdb6b3..1ae5217 100644 >>>--- a/lib/netdev-dpdk.c >>>+++ b/lib/netdev-dpdk.c >>>@@ -1193,7 +1193,8 @@ dpdk_init(int argc, char **argv) >>> rte_memzone_dump(); >>> rte_eal_init_ret = 0; >>> >>>- return result; >>>+ /* We need to skip 'result' arguments plus the "--dpdk" argument >>>itself */ >>>+ return result + 1; >>> } >>> >>> void >>>-- >>>2.0.0 >>> >>>_______________________________________________ >>>dev mailing list >>>dev@openvswitch.org >>>https://urldefense.proofpoint.com/v1/url?u=http://openvswitch.org/mailma >>>n/ >>>listinfo/dev&k=oIvRg1%2BdGAgOoM1BIlLLqw%3D%3D%0A&r=TfBS78Vw3dzttvXidhbff >>>g% >>>3D%3D%0A&m=YHHbETWmp5Oa3XgP%2BcIg9XyAXHfV73IFEmQJ8uMHZcs%3D%0A&s=4306bd1 >>>6f >>>cbb62b8d4255b12d84dfc16ba8fde09d0d0bba9bf0e110877852ea2 >> >> _______________________________________________ >> dev mailing list >> dev@openvswitch.org >> >>https://urldefense.proofpoint.com/v1/url?u=http://openvswitch.org/mailman >>/listinfo/dev&k=oIvRg1%2BdGAgOoM1BIlLLqw%3D%3D%0A&r=TfBS78Vw3dzttvXidhbff >>g%3D%3D%0A&m=z3zvkqljqI%2BZ1%2B5CXFQJqhn%2BJeuJJy0OURBm8ICxMzc%3D%0A&s=97 >>339566f48e933a25c3fc3abff1f0bb66f1bfaca89edd76a88006c5929d9efe _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
