On Thu, Jul 04, 2019 at 01:55:14PM +0000, Zhang, Qi Z wrote: > > > > -----Original Message----- > > From: Adrien Mazarguil [mailto:adrien.mazarg...@6wind.com] > > Sent: Thursday, July 4, 2019 5:07 PM > > To: Su, Simei <simei...@intel.com> > > Cc: Zhang, Qi Z <qi.z.zh...@intel.com>; Wu, Jingjing > > <jingjing...@intel.com>; > > Xing, Beilei <beilei.x...@intel.com>; Yang, Qiming <qiming.y...@intel.com>; > > dev@dpdk.org > > Subject: Re: [dpdk-dev] [RFC] ethdev: support input set change by RSS action > > > > On Thu, Jul 04, 2019 at 12:47:09PM +0800, simei wrote: > > > From: Simei Su <simei...@intel.com> > > > > > > This RFC introduces inputset structure to rte_flow_action_rss to > > > support input set specific configuration by rte_flow RSS action. > > > > > > We can give an testpmd command line example to make it more clear. > > > > > > For example, below flow selects the l4 port as inputset for any > > > eth/ipv4/tcp packet: #flow create 0 ingress pattern eth / ipv4 / tcp / > > > end actions rss inputset tcp src mask 0xffff dst mask 0xffff /end > > > > > > Signed-off-by: Simei Su <simei...@intel.com> > > > --- > > > lib/librte_ethdev/rte_flow.h | 3 +++ > > > 1 file changed, 3 insertions(+) > > > > > > diff --git a/lib/librte_ethdev/rte_flow.h > > > b/lib/librte_ethdev/rte_flow.h index f3a8fb1..2a455b6 100644 > > > --- a/lib/librte_ethdev/rte_flow.h > > > +++ b/lib/librte_ethdev/rte_flow.h > > > @@ -1796,6 +1796,9 @@ struct rte_flow_action_rss { > > > uint32_t queue_num; /**< Number of entries in @p queue. */ > > > const uint8_t *key; /**< Hash key. */ > > > const uint16_t *queue; /**< Queue indices to use. */ > > > + struct rte_flow_item *inputset; /** Provide more specific inputset > > configuration. > > > + * ignore spec, only mask. > > > + */ > > > }; > > > > > > /** > > > > To make sure I understand, is this kind of a more flexible version of > > rte_flow_action_rss.types? > > Yes > > > > For instance while specifying .types = ETH_RSS_IPV4 normally covers both > > source and destination addresses, does this approach enable users to perform > > RSS on source IP only? > > Yes, .it is the case to select any subset of 5 tuples or even tunnel header's > id for hash > > > In which case, what value does the Toeplitz algorithm > > assume for the destination, 0x0? (note: must be documented) > > My understanding is src/dst pair is only required for a symmetric case > But for Toeplitz, it is just a hash function, it process a serial of data > with specific algorithm, have no idea about which part is src and dst , > So for ip src only with Toeplitz, dst is not required to be a placeholder..
Right, I had symmetric Toeplitz in mind and wondered what would happen when users would not select the required fields. I guess the PMD would have to reject unsupported combinations. > anything I missed, would you share more insight? No, that answers the question, thanks. Now what about my suggestion below? In short: extending ETH_RSS_* assuming there's enough bits left in there, instead of adding a whole new framework and breaking ABI in the process. > > My opinion is that, unless you know of a hardware which can perform RSS on > > random bytes of a packet, this approach is a bit overkill at this point. > > > > How about simply adding the needed ETH_RSS_* definitions (e.g. > > ETH_RSS_IPV4_(SRC|DST))? How many are needed? > > > > There are currently 20 used bits and struct rte_flow_action_rss.types is > > 64-bit > > wide. I'm sure we can manage something without harming the ABI. Even > > better, you wouldn't need a deprecation notice. > > > > If you use the suggested approach, please update testpmd and its > > documentation as part of the same patch, thanks. -- Adrien Mazarguil 6WIND
