Hi
> -----Original Message-----
> From: Suanming Mou <suanmi...@nvidia.com>
> Sent: Wednesday, January 31, 2024 4:48 AM
>
> Hi,
>
> > -----Original Message-----
> > From: Ferruh Yigit <ferruh.yi...@amd.com>
> > Sent: Wednesday, January 31, 2024 1:34 AM
> > To: Suanming Mou <suanmi...@nvidia.com>; Ori Kam
> <or...@nvidia.com>;
> > Aman Singh <aman.deep.si...@intel.com>; Yuying Zhang
> > <yuying.zh...@intel.com>; NBU-Contact-Thomas Monjalon (EXTERNAL)
> > <tho...@monjalon.net>; Andrew Rybchenko
> > <andrew.rybche...@oktetlabs.ru>
> > Cc: dev@dpdk.org
> > Subject: Re: [PATCH v3 2/3] ethdev: add compare item
> >
> > On 1/15/2024 9:13 AM, Suanming Mou wrote:
> > > The new item type is added for the case user wants to match traffic
> > > based on packet field compare result with other fields or immediate
> > > value.
> > >
> > > e.g. take advantage the compare item user will be able to accumulate a
> > > IPv4/TCP packet's TCP data_offset and IPv4 IHL field to a tag
> > > register, then compare the tag register with IPv4 header total length
> > > to understand the packet has payload or not.
> > >
> >
> > ack, above sample makes it easier to understand.
> >
> > This patch is adding testpmd commands, can you please provide some
> sample
> > commands in commit log?
> > The more samples are better, as far as I remember there was a testpmd
> > documentation that documents the sample usages, can you please check
> for it?
[Snip ..]
> >
> > > +/**
> > > + * @warning
> > > + * @b EXPERIMENTAL: this structure may change without prior notice
> > > + *
> > > + * Field description for packet field.
> > > + */
> > > +struct rte_flow_field_data {
> > > + enum rte_flow_field_id field; /**< Field or memory type ID. */
> > > + union {
> > > + struct {
> > > + /** Encapsulation level and tag index or flex item
> > handle. */
> > > + union {
> > > + struct {
> > > + /**
> > > + * Packet encapsulation level
> containing
> > > + * the field to modify.
> > > + *
> > > + * - @p 0 requests the default
> behavior.
> > > + * Depending on the packet type, it
> > > + * can mean outermost, innermost
> or
> > > + * anything in between.
> > > + *
> > > + * It basically stands for the
> > > + * innermost encapsulation level.
> > > + * Modification can be performed
> > > + * according to PMD and device
> > > + * capabilities.
> > > + *
> > > + * - @p 1 requests modification to be
> > > + * performed on the outermost
> packet
> > > + * encapsulation level.
> > > + *
> > > + * - @p 2 and subsequent values
> > request
> > > + * modification to be performed on
> > > + * the specified inner packet
> > > + * encapsulation level, from
> > > + * outermost to innermost (lower to
> > > + * higher values).
> > > + *
> > > + * Values other than @p 0 are not
> > > + * necessarily supported.
> > > + *
> > > + * @note that for MPLS field,
> > > + * encapsulation level also include
> > > + * tunnel since MPLS may appear in
> > > + * outer, inner or tunnel.
> > > + */
> > > + uint8_t level;
> > > + union {
> > > + /**
> > > + * Tag index array inside
> > > + * encapsulation level.
> > > + * Used for VLAN, MPLS or
> TAG
> > types.
> > > + */
> > > + uint8_t tag_index;
> > > + /**
> > > + * Geneve option identifier.
> > > + * Relevant only for
> > > + *
> > RTE_FLOW_FIELD_GENEVE_OPT_XXXX
> > > + * modification type.
> > > + */
> > > + struct {
> > > + /**
> > > + * Geneve option
> type.
> > > + */
> > > + uint8_t type;
> > > + /**
> > > + * Geneve option
> class.
> > > + */
> > > + rte_be16_t class_id;
> > > + };
> > > + };
> > > + };
> > > + struct rte_flow_item_flex_handle
> *flex_handle;
> > > + };
> > > + /** Number of bits to skip from a field. */
> > > + uint32_t offset;
> > > + };
> > > + /**
> > > + * Immediate value for RTE_FLOW_FIELD_VALUE, presented
> in
> > the
> > > + * same byte order and length as in relevant
> rte_flow_item_xxx.
> > > + * The immediate source bitfield offset is inherited from
> > > + * the destination's one.
> > > + */
> > > + uint8_t value[16];
> > > + /**
> > > + * Memory address for RTE_FLOW_FIELD_POINTER, memory
> > layout
> > > + * should be the same as for relevant field in the
> > > + * rte_flow_item_xxx structure.
> > > + */
> > > + void *pvalue;
> > > + };
> > > +};
> > > +
> > >
> >
> > I am aware that you are just moving the above struct, but it is nested too
> much
> > which is making it hard to read.
> >
> > As you are touching it, can we extract some structs and make this struct
> > less
> > nested, what do you think?
> > Of course it needs to be done in separate patch, as a preperation/clean-up
> patch
> > before moving it around.
>
> Agree the struct maybe a bit nested. But not sure how it was discussed
> before during the last new member was added... @Ori, Do you have any idea
> about this?
>
As far as I remember, it was never discussed,
I think for this series we should keep it as is, and revise it later.
Best,
Ori
> And if it is really expected, I believe another new thread is worth for that
> change, better not be in that series.
> Need to discuss the new struct name and other stuff. What do you think?
>
> >
> > <...>
> >
> > > +/**
> > > + *
> > > + * RTE_FLOW_ITEM_TYPE_COMPARE
> > > + *
> > > + * Matches the packet with compare result.
> > > + *
> > > + * The operation means a compare with b result.
> > > + */
> > > +struct rte_flow_item_compare {
> > > + enum rte_flow_item_compare_op operation; /* The compare
> operation.
> > */
> > > + struct rte_flow_field_data a; /* Field be compared. */
> > > + struct rte_flow_field_data b; /* Field as comparator. */
> > >
> >
> > Variable names 'a' and 'b' are not descriptive although it may be OK since
> there is
> > no significance to the values, but other option can be 'first' and 'second',
> but
> > overall not strong opinion.
>
> Yes, thanks for the suggestion, in fact we also discussed about the name a
> lot,
> finally we choose the widely used 'a' and 'b'
>
> Thanks
