On Aug 24, 2015 21:54, "Zhang, Helin" <helin.zhang at intel.com> wrote: > > > > > -----Original Message----- > > From: Vlad Zolotarov [mailto:vladz at cloudius-systems.com] > > Sent: Monday, August 24, 2015 11:26 AM > > To: Zhang, Helin; Gleb Natapov > > Cc: dev at dpdk.org > > Subject: Re: [dpdk-dev] i40e and RSS woes > > > > > > > > On 08/24/15 20:51, Zhang, Helin wrote: > > > > > >> -----Original Message----- > > >> From: Vlad Zolotarov [mailto:vladz at cloudius-systems.com] > > >> Sent: Monday, August 24, 2015 4:14 AM > > >> To: Zhang, Helin; Gleb Natapov; dev at dpdk.org > > >> Subject: Re: [dpdk-dev] i40e and RSS woes > > >> > > >> > > >> > > >> On 03/05/15 07:56, Zhang, Helin wrote: > > >>> Hi Gleb > > >>> > > >>> Sorry for late! I am struggling on my tasks for the following DPDK > > >>> release these > > >> days. > > >>>> -----Original Message----- > > >>>> From: Gleb Natapov [mailto:gleb at cloudius-systems.com] > > >>>> Sent: Monday, March 2, 2015 8:56 PM > > >>>> To: dev at dpdk.org > > >>>> Cc: Zhang, Helin > > >>>> Subject: Re: i40e and RSS woes > > >>>> > > >>>> Ping. > > >>>> > > >>>> On Thu, Feb 19, 2015 at 04:50:10PM +0200, Gleb Natapov wrote: > > >>>>> CCing i40e driver author in a hope to get an answer. > > >>>>> > > >>>>> On Mon, Feb 16, 2015 at 03:36:54PM +0200, Gleb Natapov wrote: > > >>>>>> I have an application that works reasonably well with ixgbe > > >>>>>> driver, but when I try to use it with i40e I encounter various RSS related > > issues. > > >>>>>> > > >>>>>> First one is that for some reason i40e, when it builds default > > >>>>>> reta table, round down number of queues to power of two. Why is > > >>>>>> this? If > > >>> It seems because of i40e queue configuration. We will check it more > > >>> and see if it can be changed or improved later. > > >> Helin, hi! > > >> Sorry for bringing it back but it seems that the RSS queues number > > >> issue (rounding it down to the nearest power of 2) still hasn't been > > >> addressed in the master branch. > > >> > > >> Could u, pls., clarify what is that "i40e queue configuration" that > > >> requires this alignment u are referring above? > > >> > > >> From what i could see "num" parameter is not propagated outside the > > >> i40e_pf_config_rss() in any form except for RSS table contents. > > >> This means that any code that would need to know the number of Rx > > >> queues would use the dev_data->nb_rx_queues (e.g. i40e_dev_rx_init()) > > >> and wouldn't be able to know that i40e_pf_config_rss() something > > >> different except for scanning the RSS table in HW which is of course not an > > option. > > >> > > >> Therefore, from the first look it seems that this rounding may be > > >> safely removed unless I've missed something. > > > Could you help to refer to the data sheet of 'Hash Filter', 'Receive > > > Queue Regions', it is said that '1, 2, 4, 8, 16, 32, 64' are the supported queue > > regions. > > > Yes, we should support more than 64 queues per port, but for rss, it > > > should be one of '1, 2, 4, 8, 16, 32, 64'. > > > > "The VSIs support 8 regions of receive queues that are aimed mainly for the TCs. > > The TC regions are defined per VSI by the VSIQF_TCREGION register. The region > > sizes (defined by the TC_SIZE fields) can be any of the following value: 1, 2, 4, 8, > > 16, 32, 64 as long as the total number of queues do not exceed the VSI allocation. > > These regions starts at the offset defined by the TC_OFFSET parameter. > > According to the region size, the 'n' LS bits of the Queue Index from the LUT are > > enabled." > > > > I think the above says that the region sizes may only be one of the mentioned > > values. > > > > AFAIU this doesn't mean that the number or RSS queues has to be the same > > - it may not exceed it. > > > > Just like it's stated in the "Outcome Queue Index" definition the final mapping to > > the PF index space is done using the VSILAN_QTABLE or VSILAN_QBASE registers > > (a.k.a. RSS indirection table). > > > > For instance if u have a region of size 8 u may configure 3 RSS queues by setting > > the following RSS table: > > 0,1,2,0,1,2,0,1 > I tend to agree with you. Anyway, I am working on supporting more queues per port than 64, > and I will take this into account. If not other strong reasons, I will change it. Thank you very much!
Great! Thanks a lot, Helin. > > Regards, > Helin > > > > > > > > > Thanks, > > > Helin > > > > > >> Pls., comment. > > >> > > >> thanks, > > >> vlad > > >> > > >>>>>> I configure reta by my own using all of the queues everything > > >>>>>> seams to be working. To add insult to injury I do not get any > > >>>>>> errors during configuration some queues just do not receive any traffic. > > >>>>>> > > >>>>>> The second problem is that for some reason i40e does not use 40 > > >>>>>> byte toeplitz hash key like any other driver, but it expects the > > >>>>>> key to be 52 bytes. And it would have being fine (if we ignore > > >>>>>> the fact that it contradicts MS spec), but how my high level code > > >>>>>> suppose to know > > >>>> that? > > >>> Actually a rss_key_len was introduced in struct rte_eth_rss_conf > > >>> recently. So the length should be indicated clearly. But I found the > > >>> annotations of that structure should have been reworked. I will try > > >>> to rework it > > >> with clear descriptions. > > >>>>>> And again, device configuration does not fail when wrong key > > >>>>>> length is provided, it just uses some other key. Guys this kind > > >>>>>> of error handling is completely unacceptable. > > >>> If less length of key is provided, it will not be used at all, the > > >>> default key will be > > >> used. > > >>> So there is no issue as you said. But we need to add more clear > > >>> description for the structure of rte_eth_rss_conf. > > >>> > > >>> Thank you very much for the good comments! > > >>> > > >>> Regards, > > >>> Helin > > >>> > > >>>>>> The last one is more of a question. Why interface to change RSS > > >>>>>> hash function (XOR or toeplitz) is part of a filter configuration > > >>>>>> and not rss config? > > >>>>>> > > >>>>>> -- > > >>>>>> Gleb. > > >>>>> -- > > >>>>> Gleb. > > >>>> -- > > >>>> Gleb. >
