Hi Cascardo,
thanks for your input on this. It's quite messy right now, but I believe
we have a chance
to fix this up.
Replies inline
2016-07-26 7:33 GMT-07:00 Thadeu Lima de Souza Cascardo <casca...@redhat.com
>:
> On Mon, Jul 25, 2016 at 11:03:29AM -0700, Daniele Di Proietto wrote:
> > 2016-07-25 9:57 GMT-07:00 Thadeu Lima de Souza Cascardo <
> casca...@redhat.com
> > >:
> >
> > > On Fri, Jul 22, 2016 at 02:49:39PM -0700, Daniele Di Proietto wrote:
> > > > I would prefer if dpctl kept using the datapath types. The
> translation
> > > > from database types to datapath type should happen in ofproto, dpctl
> is
> > > > supposed to be used to interact with the datapath directly.
> > > >
> > > > What do you guys think?
> > > >
> > > > The rest of the series looks good to me as well.
> > > >
> > > > Thanks,
> > > >
> > > > Daniele
> > > >
> > >
> > >
> > Hi Cascardo,
> >
> > Thanks for the detailed analysis. The problem is that there are three
> > types:
> >
> > a) the database type
> > b) the port type in dpif-netdev
> > c) the netdev type
> >
> > I was assuming that b and c are always equal, but they're not. The only
> > case
> > when they're not equal is the "ovs-netdev" (or "ovs-dummy") port.
> >
> > I think we can easily remove this case and make b and c always equal
> > with the following changes:
>
> Well, we also have ofproto type.
>
>
If I'm not mistaken, ofproto type is always equal to b) and therefore to c).
> I had a different approach, in which I would use the netdev_type when
> doing the
> query. That broke tests too. The affected tests were just dpctl output
> shown to
> the user. But I would expect some breakage when ofproto_query also used
> the same
> type and vswitchd would see the database type and ofproto type as
> different and
> try to reconfigure the port.
>
>
I don't think so. In bridge_delete_or_reconfigure() we compare the ofproto
type with
iface->netdev_type:
if (strcmp(ofproto_port.type, iface->netdev_type)
|| netdev_set_config(iface->netdev, &iface->cfg->options,
NULL)) {
/* The interface is the wrong type or can't be configured.
* Delete it. */
goto delete;
}
> Then, I looked at your patch below and noticed that you do the opposite,
> you
> eliminate the open_type and only use it for the internal type. Then I
> thought
> that would break other cases. But dpif_netdev_port_add uses the netdev_type
> already. Hey...
>
> So, dpctl does see it as tap when I add an internal port. Which probably
> means
> ofproto_type is also tap. I guess we will have to fix that too.
>
To sum up, why do we have to fix that? The translation between the database
type and the netdev type happens in vswitchd/bridge.c. The below layers,
ofproto
and dpif-netdev, deal with the netdev type directly.
Is there a problem with this approach?
The few changes I suggested fix the confusion for the "ovs-netdev" port.
>
> I am attaching my version of the patch here as well. Which of the 3
> versions do
> you think I should send? The original one I sent will not require changes
> in the
> tests and also doesn't change behavior for the user output, so I would
> stick to
> it for now.
>
Why is the code below necessary? ofproto already deals with the netdev
type only, right?
(maybe I'm missing something here, probably)
>
> Cascardo.
>
> ---8<---
> diff --git a/lib/dpif-netdev.c b/lib/dpif-netdev.c
> index 37c2631..19b1f87 100644
> --- a/lib/dpif-netdev.c
> +++ b/lib/dpif-netdev.c
> @@ -1437,11 +1437,12 @@ do_del_port(struct dp_netdev *dp, struct
> dp_netdev_port *port)
> }
>
> static void
> -answer_port_query(const struct dp_netdev_port *port,
> +answer_port_query(struct dp_netdev *dp OVS_UNUSED, const struct
> dp_netdev_port *port,
> struct dpif_port *dpif_port)
> {
> + const char *type = dpif_netdev_port_open_type(dp->class, port->type);
> dpif_port->name = xstrdup(netdev_get_name(port->netdev));
> - dpif_port->type = xstrdup(port->type);
> + dpif_port->type = xstrdup(type);
> dpif_port->port_no = port->port_no;
> }
>
> @@ -1456,7 +1457,7 @@ dpif_netdev_port_query_by_number(const struct dpif
> *dpif, odp_port_t port_no,
> ovs_mutex_lock(&dp->port_mutex);
> error = get_port_by_number(dp, port_no, &port);
> if (!error && dpif_port) {
> - answer_port_query(port, dpif_port);
> + answer_port_query(dp, port, dpif_port);
> }
> ovs_mutex_unlock(&dp->port_mutex);
>
> @@ -1474,7 +1475,7 @@ dpif_netdev_port_query_by_name(const struct dpif
> *dpif, const char *devname,
> ovs_mutex_lock(&dp->port_mutex);
> error = get_port_by_name(dp, devname, &port);
> if (!error && dpif_port) {
> - answer_port_query(port, dpif_port);
> + answer_port_query(dp, port, dpif_port);
> }
> ovs_mutex_unlock(&dp->port_mutex);
>
> ---8<---
>
> >
> > ---8<---
> > diff --git a/lib/dpif-netdev.c b/lib/dpif-netdev.c
> > index 787851d..effa7e0 100644
> > --- a/lib/dpif-netdev.c
> > +++ b/lib/dpif-netdev.c
> > @@ -941,7 +941,9 @@ create_dp_netdev(const char *name, const struct
> > dpif_class *class,
> > ovs_mutex_lock(&dp->port_mutex);
> > dp_netdev_set_nonpmd(dp);
> >
> > - error = do_add_port(dp, name, "internal", ODPP_LOCAL);
> > + error = do_add_port(dp, name, dpif_netdev_port_open_type(dp->class,
> > +
> "internal"),
> > + ODPP_LOCAL);
> > ovs_mutex_unlock(&dp->port_mutex);
> > if (error) {
> > dp_netdev_free(dp);
> > @@ -1129,7 +1131,7 @@ hash_port_no(odp_port_t port_no)
> > }
> >
> > static int
> > -port_create(const char *devname, const char *open_type, const char
> *type,
> > +port_create(const char *devname, const char *type,
> > odp_port_t port_no, struct dp_netdev_port **portp)
> > {
> > struct netdev_saved_flags *sf;
> > @@ -1142,7 +1144,7 @@ port_create(const char *devname, const char
> > *open_type, const char *type,
> > *portp = NULL;
> >
> > /* Open and validate network device. */
> > - error = netdev_open(devname, open_type, &netdev);
> > + error = netdev_open(devname, type, &netdev);
> > if (error) {
> > return error;
> > }
> > @@ -1233,8 +1235,7 @@ do_add_port(struct dp_netdev *dp, const char
> > *devname, const char *type,
> > return EEXIST;
> > }
> >
> > - error = port_create(devname, dpif_netdev_port_open_type(dp->class,
> > type),
> > - type, port_no, &port);
> > + error = port_create(devname, type, port_no, &port);
> > if (error) {
> > return error;
> > }
> > root@diproiettod-dev:~/ovs# git diff
> > diff --git a/lib/dpif-netdev.c b/lib/dpif-netdev.c
> > index 787851d..effa7e0 100644
> > --- a/lib/dpif-netdev.c
> > +++ b/lib/dpif-netdev.c
> > @@ -941,7 +941,9 @@ create_dp_netdev(const char *name, const struct
> > dpif_class *class,
> > ovs_mutex_lock(&dp->port_mutex);
> > dp_netdev_set_nonpmd(dp);
> >
> > - error = do_add_port(dp, name, "internal", ODPP_LOCAL);
> > + error = do_add_port(dp, name, dpif_netdev_port_open_type(dp->class,
> > +
> "internal"),
> > + ODPP_LOCAL);
> > ovs_mutex_unlock(&dp->port_mutex);
> > if (error) {
> > dp_netdev_free(dp);
> > @@ -1129,7 +1131,7 @@ hash_port_no(odp_port_t port_no)
> > }
> >
> > static int
> > -port_create(const char *devname, const char *open_type, const char
> *type,
> > +port_create(const char *devname, const char *type,
> > odp_port_t port_no, struct dp_netdev_port **portp)
> > {
> > struct netdev_saved_flags *sf;
> > @@ -1142,7 +1144,7 @@ port_create(const char *devname, const char
> > *open_type, const char *type,
> > *portp = NULL;
> >
> > /* Open and validate network device. */
> > - error = netdev_open(devname, open_type, &netdev);
> > + error = netdev_open(devname, type, &netdev);
> > if (error) {
> > return error;
> > }
> > @@ -1233,8 +1235,7 @@ do_add_port(struct dp_netdev *dp, const char
> > *devname, const char *type,
> > return EEXIST;
> > }
> >
> > - error = port_create(devname, dpif_netdev_port_open_type(dp->class,
> > type),
> > - type, port_no, &port);
> > + error = port_create(devname, type, port_no, &port);
> > if (error) {
> > return error;
> > }
> > ---8<---
> >
> > With this incremental case 2 is covered, dpctl/show always shows the
> > datapath type.
> > (The incremental also requires some testsuite changes)
> >
> > For case 1 and 3 is just a matter of deciding if we want to support
> database
> > types (in addition to netdev) in dpctl. I would lean towards no: I find
> it
> > confusing
> > that both types are acceptable.
> >
> > That said, I feel like I'm nitpicking, dpctl is a tool used for debugging
> > and I think
> > we should do whatever comes easier.
> >
> > Thanks,
> >
> > Daniele
> >
> > Hi, Daniele.
> > >
> > > Thanks for the comment.
> > >
> > > The best example that breaks currently is the internal type on the
> netdev
> > > datapath.
> > >
> > > There are three scenarios in dpctl, and two of them are changed with
> this
> > > patch.
> > >
> > > 1) The user input type, given for add-if. In this particular case, the
> code
> > > would try to use the "internal" type, but thinks would break as the
> Linux
> > > internal type would not work for the netdev datapath. The user was
> > > expected to
> > > use "tap" instead. We the patch applied, either way should work. So we
> are
> > > not
> > > breaking behavior.
> > >
> > > 2) When the type is output to the user. The current patch does not
> change
> > > its
> > > behavior, which basically prints what we get from dpif_port_query.
> However,
> > > dpif-netdev uses a cache of the database type and returns that, not the
> > > netdev
> > > type. That could be changed, but then the output to the user would be
> the
> > > real
> > > dpif. Would that be acceptable? It could break scripts out there which
> > > look for
> > > internal. Or would dpctl do the reverse mapping? That would require
> some
> > > new
> > > code on the dpif level.
> > >
> >
> > > 3) Using the dpif_port.type in netdev_open. We could use the same
> > > alternative
> > > solution here as proposed for scenario 2. Make dpif_port_query return
> the
> > > real
> > > netdev type. This would require the new reverse mapping in order to be
> > > used also
> > > at the ofproto level, so ofproto_port_query uses the database type.
> > >
> > > I have a patch that changes dpif-netdev to return the netdev open type.
> > > However,
> > > as it broke dpctl output, I decided to provice this current patch
> instead,
> > > as I
> > > realized a lot more would be needed on other code, and we risked
> breaking
> > > a lot
> > > of behavior.
> > >
> > > I would keep this patch as is in the series, as it keeps behavior, and
> > > improves
> > > the case in add-if, without breaking it; and leave the dpif_port_query
> fix
> > > and
> > > reverse mapping to another day.
> > >
> > > What do you think?
> > >
> > > Regards.
> > > Cascardo.
> > >
> > >
> > > > 2016-07-18 10:00 GMT-07:00 Thadeu Lima de Souza Cascardo <
> > > > casca...@redhat.com>:
> > > >
> > > > > dpctl uses a user or database defined type when calling
> netdev_open.
> > > > > Instead, it
> > > > > should use the type from dpif_port_open_type. Otherwise, when
> using the
> > > > > internal
> > > > > type, it could open it with that type instead of the correct one,
> which
> > > > > would be
> > > > > tap or dummy.
> > > > > ---
> > > > > lib/dpctl.c | 17 ++++++++++++-----
> > > > > 1 file changed, 12 insertions(+), 5 deletions(-)
> > > > >
> > > > > diff --git a/lib/dpctl.c b/lib/dpctl.c
> > > > > index 003602a..f896161 100644
> > > > > --- a/lib/dpctl.c
> > > > > +++ b/lib/dpctl.c
> > > > > @@ -274,7 +274,8 @@ dpctl_add_if(int argc OVS_UNUSED, const char
> > > *argv[],
> > > > > }
> > > > > }
> > > > >
> > > > > - error = netdev_open(name, type, &netdev);
> > > > > + error = netdev_open(name,
> dpif_port_open_type(dpif_type(dpif),
> > > > > type),
> > > > > + &netdev);
> > > > > if (error) {
> > > > > dpctl_error(dpctl_p, error, "%s: failed to open
> network
> > > > > device",
> > > > > name);
> > > > > @@ -356,7 +357,8 @@ dpctl_set_if(int argc, const char *argv[],
> struct
> > > > > dpctl_params *dpctl_p)
> > > > > dpif_port_destroy(&dpif_port);
> > > > >
> > > > > /* Retrieve its existing configuration. */
> > > > > - error = netdev_open(name, type, &netdev);
> > > > > + error = netdev_open(name,
> dpif_port_open_type(dpif_type(dpif),
> > > > > type),
> > > > > + &netdev);
> > > > > if (error) {
> > > > > dpctl_error(dpctl_p, error, "%s: failed to open
> network
> > > > > device",
> > > > > name);
> > > > > @@ -558,10 +560,13 @@ show_dpif(struct dpif *dpif, struct
> dpctl_params
> > > > > *dpctl_p)
> > > > > qsort(port_nos, n_port_nos, sizeof *port_nos,
> compare_port_nos);
> > > > >
> > > > > for (int i = 0; i < n_port_nos; i++) {
> > > > > + const char *type;
> > > > > if (dpif_port_query_by_number(dpif, port_nos[i],
> &dpif_port))
> > > {
> > > > > continue;
> > > > > }
> > > > >
> > > > > + type = dpif_port_open_type(dpif_type(dpif),
> dpif_port.type);
> > > > > +
> > > > > dpctl_print(dpctl_p, "\tport %u: %s",
> > > > > dpif_port.port_no, dpif_port.name);
> > > > >
> > > > > @@ -570,7 +575,7 @@ show_dpif(struct dpif *dpif, struct
> dpctl_params
> > > > > *dpctl_p)
> > > > >
> > > > > dpctl_print(dpctl_p, " (%s", dpif_port.type);
> > > > >
> > > > > - error = netdev_open(dpif_port.name, dpif_port.type,
> > > &netdev);
> > > > > + error = netdev_open(dpif_port.name, type, &netdev);
> > > > > if (!error) {
> > > > > struct smap config;
> > > > >
> > > > > @@ -603,7 +608,7 @@ show_dpif(struct dpif *dpif, struct
> dpctl_params
> > > > > *dpctl_p)
> > > > > struct netdev_stats s;
> > > > > int error;
> > > > >
> > > > > - error = netdev_open(dpif_port.name, dpif_port.type,
> > > &netdev);
> > > > > + error = netdev_open(dpif_port.name, type, &netdev);
> > > > > if (error) {
> > > > > dpctl_print(dpctl_p, ", open failed (%s)",
> > > > > ovs_strerror(error));
> > > > > @@ -891,6 +896,7 @@ get_in_port_netdev_from_key(struct dpif *dpif,
> > > const
> > > > > struct ofpbuf *key)
> > > > > struct dpif_port dpif_port;
> > > > > odp_port_t port_no;
> > > > > int error;
> > > > > + const char *type;
> > > > >
> > > > > port_no = ODP_PORT_C(nl_attr_get_u32(in_port_nla));
> > > > > error = dpif_port_query_by_number(dpif, port_no,
> &dpif_port);
> > > > > @@ -898,7 +904,8 @@ get_in_port_netdev_from_key(struct dpif *dpif,
> > > const
> > > > > struct ofpbuf *key)
> > > > > goto out;
> > > > > }
> > > > >
> > > > > - netdev_open(dpif_port.name, dpif_port.type, &dev);
> > > > > + type = dpif_port_open_type(dpif_type(dpif),
> dpif_port.type);
> > > > > + netdev_open(dpif_port.name, type, &dev);
> > > > > dpif_port_destroy(&dpif_port);
> > > > > }
> > > > >
> > > > > --
> > > > > 2.7.4
> > > > >
> > > > > _______________________________________________
> > > > > dev mailing list
> > > > > dev@openvswitch.org
> > > > > http://openvswitch.org/mailman/listinfo/dev
> > > > >
> > > > _______________________________________________
> > > > dev mailing list
> > > > dev@openvswitch.org
> > > > http://openvswitch.org/mailman/listinfo/dev
> > >
> > _______________________________________________
> > dev mailing list
> > dev@openvswitch.org
> > http://openvswitch.org/mailman/listinfo/dev
>
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