Hi Ivan.
> -----Original Message-----
> From: Ivan Malov <ivan.ma...@oktetlabs.ru>
> Sent: Sunday, October 10, 2021 4:30 PM
> Subject: Re: [PATCH v2 01/12] ethdev: add port representor item to flow API
>
> Hi Ori,
>
> Thanks a lot for reviewing this.
>
> On 10/10/2021 14:15, Ori Kam wrote:
> > Hi Ivan,
> >
> >>From the new patches I saw you choose port_representor and
> >>represented_port
> > Didn't we agree to go with ETHDEV_PORT and SHADOW_PORT?
>
> Yes, in the previous thread I suggested a different option. But I gave it
> more thought and decided to go for
> PORT_REPRESENTOR and REPRESENTED_PORT instead. In any case, I apologise for
> it being such short
> notice.
>
> > The only thing that worries me is that the naming are very easy to get
> > wrong.
> > port_representor and represented_port.
>
> Is that so? In "port representor", the key word is "representor", a noun. In
> "represented port", the key
> word is "port". Word "represented"
> acts like an adjective. More to that, the order of words is chosen on purpose
> to prevent someone from
> accidentally writing "representOR_port"
> in their code, for example. That simply won't compile.
>
> Well, at least, these two are harder to get wrong compared to "employer"
> and "employee", for example.
>
> The new names are better because they are paired terms. Each one suggests the
> existence of the other
> one. This spares one from the need to have wordy explanations of the symmetry
> of the diagram.
> The new names speak themselves.
>
> Saying "shadow" is in fact vague. The reader doesn't see clearly that it's
> the shadow of the ethdev. And, in
> turn, "ethdev" is also not as good as "representor". It's even hard to
> pronounce because of being a
> combination of multiple contractions.
>
> I hope you get the idea.
>
I get the idea, since my English is not perfect from my view point those are a
bit more confusing and easy
to get wrong but I have no objection to keep them.
Lets see what others will think about it.
> >
> > Also there is an issue with wording if we assume like in previous
> > thread that DPDK can have both the representor port and also the
> > represented_port.
> > While if we look at for example ethdev_port and shadow port are better
> > defined as ethdev_port -> the port that is closest to the DPDK ethdev
> > while shadow port is defined as the other side of the ethdev port.
> >
> > What do you think?
>
> The semantics hasn't changed since the previous thread.
> Representor coincides with the ethdev, so it's still the closest port.
> And represented port is still the other side. It's all the same in fact.
>
> If both VF and its representor are plugged to DPDK, they represent each other
> in fact. Mutual
> representors. You can equally name the first one a representor and the other
> one a represented port, -
> and vice versa.
>
> The new naming doesn't deny both these ports being ethdevs, while the
> previous option (ethdev and
> shadow) may trick the reader into thinking that only one of the two can be an
> ethdev. The reader may
> think that this use case (when VF and its representor are plugged to the
> application) is completely wrong.
> Let's avoid this mistake.
>
I agree those are semantics and there is no perfect world.
I accept your case.
> >
> >> -----Original Message-----
> >> From: Ivan Malov <ivan.ma...@oktetlabs.ru>
> >> Sent: Sunday, October 10, 2021 3:05 AM
> >> Subject: [PATCH v2 01/12] ethdev: add port representor item to flow
> >> API ?
> >> For use in "transfer" flows. Supposed to match traffic entering the
> >> embedded switch from the given ethdev.
> >
> >
> > I would also add a comment that says the since we are in transfer it
> > means that all rules are located in the E-Switch which means that the
> > matching is done on the source port of the traffic.
>
> Let me put it clear: I don't mind adding more comments. I can do that, yes.
> But look. You say "matching is
> done on the source port". Isn't that what "entering the embedded switch FROM
> the given ethdev" already
> says?
>
Yes, the idea of this series is to clear everything.
Do you think that someone who just read this commit log can without prior
knowledge of RTE flow
and transfer can fully understand the idea?
If so I'm, O.K. with leaving the comment as is.
In most related comment about pharsing I'm giving my view point with all
the comments I got about how much hard it is to create rules and understand the
documentation.
Unless there is something wrong or misleading I can except most answers and
comments,
but I steel think that sometime it is worth saying them even if it is just for
the developer to think
again if something can be improved.
> >
> > I think this will also help understand the view point that we are
> > looking from the point of the switch, and to add the drawing.
>
> Well, as I said, technically, I don't object adding more comments. But the
> above description says: "entering
> the embedded switch". Doesn't it indicate the viewpoint clear enough? Should
> I reword this?
>
> Also, "flow engine" is showed in the diagram. And there are arrows.
> Doesn't that explain the viewpoint fully?
>
> I'm ready to discuss / improve.
Yes, but I was thinking about also adding it in the commit log.
>
> >
> >>
> >> Must not be combined with direction attributes.
> >>
> >> Signed-off-by: Ivan Malov <ivan.ma...@oktetlabs.ru>
> >> ---
> >> app/test-pmd/cmdline_flow.c | 27 ++++++++++
> >> doc/guides/prog_guide/rte_flow.rst | 59 +++++++++++++++++++++
> >> doc/guides/rel_notes/release_21_11.rst | 2 +
> >> doc/guides/testpmd_app_ug/testpmd_funcs.rst | 4 ++
> >> lib/ethdev/rte_flow.c | 1 +
> >> lib/ethdev/rte_flow.h | 27 ++++++++++
> >> 6 files changed, 120 insertions(+)
> >>
> >> diff --git a/app/test-pmd/cmdline_flow.c
> >> b/app/test-pmd/cmdline_flow.c index
> >> bb22294dd3..a912a8d815 100644
> >> --- a/app/test-pmd/cmdline_flow.c
> >> +++ b/app/test-pmd/cmdline_flow.c
> >> @@ -306,6 +306,8 @@ enum index {
> >> ITEM_POL_PORT,
> >> ITEM_POL_METER,
> >> ITEM_POL_POLICY,
> >> + ITEM_PORT_REPRESENTOR,
> >> + ITEM_PORT_REPRESENTOR_PORT_ID,
> >>
> >> /* Validate/create actions. */
> >> ACTIONS,
> >> @@ -1000,6 +1002,7 @@ static const enum index next_item[] = {
> >> ITEM_GENEVE_OPT,
> >> ITEM_INTEGRITY,
> >> ITEM_CONNTRACK,
> >> + ITEM_PORT_REPRESENTOR,
> >> END_SET,
> >> ZERO,
> >> };
> >> @@ -1368,6 +1371,12 @@ static const enum index item_integrity_lv[] = {
> >> ZERO,
> >> };
> >>
> >> +static const enum index item_port_representor[] = {
> >> + ITEM_PORT_REPRESENTOR_PORT_ID,
> >> + ITEM_NEXT,
> >> + ZERO,
> >> +};
> >> +
> >> static const enum index next_action[] = {
> >> ACTION_END,
> >> ACTION_VOID,
> >> @@ -3608,6 +3617,21 @@ static const struct token token_list[] = {
> >> item_param),
> >> .args = ARGS(ARGS_ENTRY(struct rte_flow_item_conntrack, flags)),
> >> },
> >> + [ITEM_PORT_REPRESENTOR] = {
> >> + .name = "port_representor",
> >> + .help = "match traffic entering the embedded switch from the
> >> given ethdev",
> >> + .priv = PRIV_ITEM(PORT_REPRESENTOR,
> >> + sizeof(struct rte_flow_item_ethdev)),
> >> + .next = NEXT(item_port_representor),
> >> + .call = parse_vc,
> >> + },
> >> + [ITEM_PORT_REPRESENTOR_PORT_ID] = {
> >> + .name = "port_id",
> >> + .help = "ethdev port ID",
> >> + .next = NEXT(item_port_representor,
> >> NEXT_ENTRY(COMMON_UNSIGNED),
> >> + item_param),
> >> + .args = ARGS(ARGS_ENTRY(struct rte_flow_item_ethdev,
> >> port_id)),
> >> + },
> >> /* Validate/create actions. */
> >> [ACTIONS] = {
> >> .name = "actions",
> >> @@ -8343,6 +8367,9 @@ flow_item_default_mask(const struct
> >> rte_flow_item
> >> *item)
> >> case RTE_FLOW_ITEM_TYPE_PFCP:
> >> mask = &rte_flow_item_pfcp_mask;
> >> break;
> >> + case RTE_FLOW_ITEM_TYPE_PORT_REPRESENTOR:
> >> + mask = &rte_flow_item_ethdev_mask;
> >> + break;
> >> default:
> >> break;
> >> }
> >> diff --git a/doc/guides/prog_guide/rte_flow.rst
> >> b/doc/guides/prog_guide/rte_flow.rst
> >> index 2b42d5ec8c..2e0f590777 100644
> >> --- a/doc/guides/prog_guide/rte_flow.rst
> >> +++ b/doc/guides/prog_guide/rte_flow.rst
> >> @@ -1425,6 +1425,65 @@ Matches a conntrack state after conntrack action.
> >> - ``flags``: conntrack packet state flags.
> >> - Default ``mask`` matches all state bits.
> >>
> >> +Item: ``PORT_REPRESENTOR``
> >> +^^^^^^^^^^^^^^^^^^^^^^^^^^
> >> +
> >> +Matches traffic entering the embedded switch from the given ethdev.
> >> +
> >> +Term **ethdev** and the concept of **port representor** are synonymous.
> >> +The **represented port** is an *entity* plugged to the embedded
> >> +switch at the opposite end of the "wire" leading to the ethdev.
> >> +
> >> +::
> >> +
> >> + .------------------------.
> >> + | PORT_REPRESENTOR | Ethdev (Application Port Referred to by
> >> its ID)
> >> + '------------------------'
> >> + ||
> >> + \/
> >> + .------------------------.
> >> + | Embedded Switch Port | Logical Port
> >> + '------------------------'
> >> + ||
> >> + ||
> >> + ||
> >> + \/
> >> + .------------------------.
> >> + | Embedded Flow Engine |
> >> + '------------------------'
> >> + :
> >> + :
> >> + :
> >> + :
> >> + .------------------------.
> >> + | Embedded Switch Port | Logical Port
> >> + '------------------------'
> >> + :
> >> + :
> >> + .------------------------.
> >> + | REPRESENTED_PORT | Net / Guest / Another Ethdev (Same
> >> Application)
> >> + '------------------------'
> >> +
> >> +
> >
> > I think this drawing is harder to understand than the one you draw in
> > the previous thread (A-> ethdev, b-> embedded switch, switch , c-> embedded
> > switch, d -> represented
> entity (shadow port).
>
> Is that so? Here's the previous drawing:
>
>
> [ A ] <-- ethdev
> |
> [ B ] <-- embedded switch (logical) port
> |
> |
> |
> =============== <-- plane of symmetry
> |
> |
> |
> [ C ] <-- embedded switch (logical) port
> |
> [ D ] <-- represented entity
>
>
> Technically, these two are exactly the same. Yes, I use precise names instead
> of letters (A, B, C, D) and
> more formatting, but that should help, not confuse.
>
> And, as I say, in the new one, I don't have to use complex terms like "plane
> of symmetry". The names
> speak for it themselves.
>
That was what I was missing and the only difference between the two,
Th plane of symmetry (I'm not sure I like this name) but it is much cleared
them embedded engine.
Embedded engine has meaning for me which is very different.
maybe just replace it with switch? Or Embedded switch?
> >
> >> +- Incompatibe with `Attribute: Traffic direction`_.
> >> +- Requires `Attribute: Transfer`_.
> >> +
> >> +.. _table_rte_flow_item_ethdev:
> >> +
> >> +.. table:: ``struct rte_flow_item_ethdev``
> >> +
> >> + +----------+-------------+---------------------------+
> >> + | Field | Subfield | Value |
> >> + +==========+=============+===========================+
> >> + | ``spec`` | ``port_id`` | ethdev port ID |
> >> + +----------+-------------+---------------------------+
> >> + | ``last`` | ``port_id`` | upper range value |
> >> + +----------+-------------+---------------------------+
> >> + | ``mask`` | ``port_id`` | zeroed for wildcard match |
> >> + +----------+-------------+---------------------------+
> >> +
> >> +- Default ``mask`` provides exact match behaviour.
> >> +
> >> Actions
> >> ~~~~~~~
> >>
> >> diff --git a/doc/guides/rel_notes/release_21_11.rst
> >> b/doc/guides/rel_notes/release_21_11.rst
> >> index 89d4b33ef1..1261cb2bf3 100644
> >> --- a/doc/guides/rel_notes/release_21_11.rst
> >> +++ b/doc/guides/rel_notes/release_21_11.rst
> >> @@ -188,6 +188,8 @@ API Changes
> >> Also, make sure to start the actual text at the margin.
> >> =======================================================
> >>
> >> +* ethdev: Added item ``PORT_REPRESENTOR`` to flow API.
> >> +
> >> * kvargs: The experimental function ``rte_kvargs_strcmp()`` has been
> >> removed. Its usages have been replaced by a new function
> >> ``rte_kvargs_get_with_value()``.
> >> diff --git a/doc/guides/testpmd_app_ug/testpmd_funcs.rst
> >> b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
> >> index 8ead7a4a71..dcb9f47d98 100644
> >> --- a/doc/guides/testpmd_app_ug/testpmd_funcs.rst
> >> +++ b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
> >> @@ -3795,6 +3795,10 @@ This section lists supported pattern items and
> >> their attributes, if any.
> >>
> >> - ``conntrack``: match conntrack state.
> >>
> >> +- ``port_representor``: match traffic entering the embedded switch
> >> +from the given ethdev
> >> +
> >> + - ``port_id {unsigned}``: ethdev port ID
> >> +
> >> Actions list
> >> ^^^^^^^^^^^^
> >>
> >> diff --git a/lib/ethdev/rte_flow.c b/lib/ethdev/rte_flow.c index
> >> 8cb7a069c8..5e9317c6d1 100644
> >> --- a/lib/ethdev/rte_flow.c
> >> +++ b/lib/ethdev/rte_flow.c
> >> @@ -100,6 +100,7 @@ static const struct rte_flow_desc_data
> >> rte_flow_desc_item[] = {
> >> MK_FLOW_ITEM(GENEVE_OPT, sizeof(struct rte_flow_item_geneve_opt)),
> >> MK_FLOW_ITEM(INTEGRITY, sizeof(struct rte_flow_item_integrity)),
> >> MK_FLOW_ITEM(CONNTRACK, sizeof(uint32_t)),
> >> + MK_FLOW_ITEM(PORT_REPRESENTOR, sizeof(struct
> >> rte_flow_item_ethdev)),
> >> };
> >>
> >> /** Generate flow_action[] entry. */ diff --git
> >> a/lib/ethdev/rte_flow.h b/lib/ethdev/rte_flow.h index
> >> 7b1ed7f110..3625fd2c12 100644
> >> --- a/lib/ethdev/rte_flow.h
> >> +++ b/lib/ethdev/rte_flow.h
> >> @@ -574,6 +574,15 @@ enum rte_flow_item_type {
> >> * @see struct rte_flow_item_conntrack.
> >> */
> >> RTE_FLOW_ITEM_TYPE_CONNTRACK,
> >> +
> >> + /**
> >> + * [META]
> >> + *
> >> + * Matches traffic entering the embedded switch from the given ethdev.
> >> + *
> >> + * @see struct rte_flow_item_ethdev
> >> + */
> >> + RTE_FLOW_ITEM_TYPE_PORT_REPRESENTOR,
> >> };
> >>
> >> /**
> >> @@ -1799,6 +1808,24 @@ static const struct rte_flow_item_conntrack
> >> rte_flow_item_conntrack_mask = { }; #endif
> >>
> >> +/**
> >> + * @warning
> >> + * @b EXPERIMENTAL: this structure may change without prior notice
> >> + *
> >> + * Provides an ethdev port ID for use with the following items:
> >> + * RTE_FLOW_ITEM_TYPE_PORT_REPRESENTOR.
> >> + */
> >> +struct rte_flow_item_ethdev {
> >> + uint16_t port_id; /**< ethdev port ID */ };
> >> +
> >> +/** Default mask for items based on struct rte_flow_item_ethdev */
> >> +#ifndef __cplusplus static const struct rte_flow_item_ethdev
> >> +rte_flow_item_ethdev_mask = {
> >> + .port_id = 0xffff,
> >> +};
> >> +#endif
> >> +
> >> /**
> >> * Matching pattern item definition.
> >> *
> >> --
> >> 2.20.1
>
> --
> Ivan M
Best,
Ori
