Re: [dpdk-dev] [PATCH v4 2/2] ethdev: update qfi definition

[Raslan Darawsheh <rasland@nvidia.com>]

Kindest regards,
Raslan Darawsheh

> -----Original Message-----
> From: Ferruh Yigit <ferruh.yigit@intel.com>
> Sent: Wednesday, April 14, 2021 3:17 PM
> To: Ori Kam <orika@nvidia.com>; Raslan Darawsheh <rasland@nvidia.com>;
> dev@dpdk.org; andrew.rybchenko@oktetlabs.ru
> Cc: ivan.malov@oktetlabs.ru; ying.a.wang@intel.com;
> olivier.matz@6wind.com; Slava Ovsiienko <viacheslavo@nvidia.com>; Shiri
> Kuzin <shirik@nvidia.com>; stable@dpdk.org; David Marchand
> <david.marchand@redhat.com>; NBU-Contact-Thomas Monjalon
> <thomas@monjalon.net>
> Subject: Re: [PATCH v4 2/2] ethdev: update qfi definition
> 
> On 4/13/2021 10:24 AM, Ori Kam wrote:
> > Hi Raslan,
> >
> >> -----Original Message-----
> >> From: Raslan Darawsheh <rasland@nvidia.com>
> >> Subject: RE: [PATCH v4 2/2] ethdev: update qfi definition
> >>
> >> Hi,
> >>
> >>> -----Original Message-----
> >>> From: Ferruh Yigit <ferruh.yigit@intel.com>
> >>> Sent: Tuesday, April 6, 2021 7:10 PM
> >>> To: Raslan Darawsheh <rasland@nvidia.com>; dev@dpdk.org; Ori Kam
> >>> <orika@nvidia.com>; andrew.rybchenko@oktetlabs.ru
> >>> Cc: ivan.malov@oktetlabs.ru; ying.a.wang@intel.com;
> >>> olivier.matz@6wind.com; Slava Ovsiienko <viacheslavo@nvidia.com>;
> Shiri
> >>> Kuzin <shirik@nvidia.com>; stable@dpdk.org; David Marchand
> >>> <david.marchand@redhat.com>; NBU-Contact-Thomas Monjalon
> >>> <thomas@monjalon.net>
> >>> Subject: Re: [PATCH v4 2/2] ethdev: update qfi definition
> >>>
> >>> On 4/4/2021 8:45 AM, Raslan Darawsheh wrote:
> >>>> qfi field is 8 bits which represent single bit for
> >>>> PPP (paging Policy Presence) single bit for RQI
> >>>> (Reflective QoS Indicator) and 6 bits for qfi
> >>>> (QoS Flow Identifier) based on RFC 38415-g30
> >>>>
> >>>> This update the doxygen format and the mask for qfi
> >>>> to properly identify the full 8 bits of the field.
> >>>>
> >>>> note: changing the default mask would cause different
> >>>> patterns generated by testpmd.
> >>>>
> >>>> Fixes: 346553db5bd1 ("ethdev: add GTP extension header to flow API")
> >>>> Cc: ying.a.wang@intel.com
> >>>> Cc: stable@dpdk.org
> >>>>
> >>>> Signed-off-by: Raslan Darawsheh <rasland@nvidia.com>
> >>>> ---
> >>>>    doc/guides/testpmd_app_ug/testpmd_funcs.rst |  3 ++-
> >>>>    lib/librte_ethdev/rte_flow.h                | 20 +++++++++++++++++---
> >>>>    2 files changed, 19 insertions(+), 4 deletions(-)
> >>>>
> >>>> diff --git a/doc/guides/testpmd_app_ug/testpmd_funcs.rst
> >>> b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
> >>>> index f59eb8a27d..dd39c4c3c2 100644
> >>>> --- a/doc/guides/testpmd_app_ug/testpmd_funcs.rst
> >>>> +++ b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
> >>>> @@ -3742,7 +3742,8 @@ This section lists supported pattern items and
> >>> their attributes, if any.
> >>>>    - ``gtp_psc``: match GTP PDU extension header with type 0x85.
> >>>>
> >>>>      - ``pdu_type {unsigned}``: PDU type.
> >>>> -  - ``qfi {unsigned}``: QoS flow identifier.
> >>>> +
> >>>> +  - ``qfi {unsigned}``: PPP, RQI and QoS flow identifier.
> >>>>
> >>>>    - ``pppoes``, ``pppoed``: match PPPoE header.
> >>>>
> >>>> diff --git a/lib/librte_ethdev/rte_flow.h b/lib/librte_ethdev/rte_flow.h
> >>>> index 6cc57136ac..20b4389429 100644
> >>>> --- a/lib/librte_ethdev/rte_flow.h
> >>>> +++ b/lib/librte_ethdev/rte_flow.h
> >>>> @@ -20,6 +20,7 @@
> >>>>    #include <rte_arp.h>
> >>>>    #include <rte_common.h>
> >>>>    #include <rte_ether.h>
> >>>> +#include <rte_gtp.h>
> >>>>    #include <rte_icmp.h>
> >>>>    #include <rte_ip.h>
> >>>>    #include <rte_sctp.h>
> >>>> @@ -1421,16 +1422,29 @@ static const struct rte_flow_item_meta
> >>> rte_flow_item_meta_mask = {
> >>>>     *
> >>>>     * Matches a GTP PDU extension header with type 0x85.
> >>>>     */
> >>>> +RTE_STD_C11
> >>>>    struct rte_flow_item_gtp_psc {
> >>>> -	uint8_t pdu_type; /**< PDU type. */
> >>>> -	uint8_t qfi; /**< QoS flow identifier. */
> >>>> +	union {
> >>>> +		struct {
> >>>> +			/*
> >>>> +			 * These fields are retained for compatibility.
> >>>> +			 * Please switch to the new header field below.
> >>>> +			 */
> >>>> +			uint8_t pdu_type; /**< PDU type. */
> >>>> +			uint8_t qfi; /**< PPP, RQI, QoS flow identifier. */
> >>>> +
> >>>> +		};
> >>>> +		struct rte_gtp_psc_hdr hdr;
> >>>> +	};
> >>>>    };
> >>>
> >>> This will change the struct size even with union, since old version is
> missing
> >>> all fields from protocol header. Struct size will go from 2 --> 5 bytes [1].
> >>>
> >>> Since this is public struct, we can't change its size.
> >>>
> >>> @Ori, Andrew,
> >>>
> >>> Do you have a suggestion for next step?
> >>>
> >
> > I think Ferruh is right, and I think that we should at this point just update
> the documentation.
> > Sorry for the detour
> > Just small comment about the original  patch.
> > I don't think you should change the default mask since it may break existing
> apps.
> >
> 
> I will continue with first patch [1], and will update the protocol reference in
> the commit log.
> 
> Meanwhile adding 'struct rte_gtp_psc_hdr' (patch v4 1/2) work can continue
> separately.
> And when it is added we can send a deprecation notice to update 'struct
> rte_flow_item_gtp_psc' and finally update it on v21.11 to have 'struct
> rte_gtp_psc_hdr' in it. Makes sense?
> 
Yes, makes sense to me, 
I'll work in the meanwhile on providing the new hdrs definition .

> [1]
> https://patches.dpdk.org/project/dpdk/patch/20210323121134.19113-1-
> rasland@nvidia.com/
> 
> >>> - We can still add the "struct rte_gtp_psc_hdr", and add a deprecation
> notice
> >>> for "struct rte_flow_item_gtp_psc" to say it will use  "struct
> >>> rte_gtp_psc_hdr"
> >>> on 21.11.
> >>>
> >>> - And for this release use the Raslan's first version:
> >>>     -	uint8_t qfi; /**< QoS flow identifier. */
> >>>     +	uint8_t qfi; /**< PPP, RQI, QoS flow identifier. */
> >>>
> >>>
> >>> Does it make sense? Any comments?
> >>>
> >> @Ori Kam, @andrew.rybchenko@oktetlabs.ru,
> >> This is a kind remainder of this patch,
> >>
> >>>
> >>>
> >>> [1]
> >>> struct rte_gtp_psc_hdr {
> >>>           uint8_t                    ext_hdr_len;          /*     0     1 */
> >>>           uint8_t                    type:4;               /*     1: 0  1 */
> >>>           uint8_t                    qmp:1;                /*     1: 4  1 */
> >>>
> >>>           /* XXX 3 bits hole, try to pack */
> >>>
> >>>           union {
> >>>                   struct {
> >>>                           uint8_t    snp:1;                /*     2: 0  1 */
> >>>                           uint8_t    spare_dl1:2;          /*     2: 1  1 */
> >>>                   };                                       /*     2     1 */
> >>>                   struct {
> >>>                           uint8_t    dl_delay_ind:1;       /*     2: 0  1 */
> >>>                           uint8_t    ul_delay_ind:1;       /*     2: 1  1 */
> >>>                           uint8_t    snp_ul1:1;            /*     2: 2  1 */
> >>>                   };                                       /*     2     1 */
> >>>           };                                               /*     2     1 */
> >>>           union {
> >>>                   struct {
> >>>                           uint8_t    ppp:1;                /*     3: 0  1 */
> >>>                           uint8_t    rqi:1;                /*     3: 1  1 */
> >>>                   };                                       /*     3     1 */
> >>>                   struct {
> >>>                           uint8_t    n_delay_ind:1;        /*     3: 0  1 */
> >>>                           uint8_t    spare_ul2:1;          /*     3: 1  1 */
> >>>                   };                                       /*     3     1 */
> >>>           };                                               /*     3     1 */
> >>>           uint8_t                    qfi:6;                /*     4: 0  1 */
> >>>
> >>>           /* XXX 2 bits hole, try to pack */
> >>>
> >>>           uint8_t                    data[];               /*     5     0 */
> >>>
> >>>           /* size: 5, cachelines: 1, members: 7 */
> >>>           /* sum members: 3 */
> >>>           /* sum bitfield members: 11 bits, bit holes: 2, sum bit holes: 5 bits
> */
> >>>           /* last cacheline: 5 bytes */
> >>> };
> >>>
> >>>>
> >>>>    /** Default mask for RTE_FLOW_ITEM_TYPE_GTP_PSC. */
> >>>>    #ifndef __cplusplus
> >>>>    static const struct rte_flow_item_gtp_psc
> >>>>    rte_flow_item_gtp_psc_mask = {
> >>>> -	.qfi = 0x3f,
> >>>> +	.hdr.ppp = 1,
> >>>> +	.hdr.rqi = 1,
> >>>> +	.hdr.qfi = 0x3f,
> >>>>    };
> >>>>    #endif
> >>>>
> >>>>
> >