On Tue, 2020-04-28 at 15:45 +0100, Bruce Richardson wrote: > On Tue, Apr 28, 2020 at 03:06:20PM +0100, Ferruh Yigit wrote: > > On 4/27/2020 5:59 PM, Jerin Jacob wrote: > > > On Mon, Apr 27, 2020 at 10:19 PM Ferruh Yigit <[email protected]> > > > wrote: > > > > On 4/27/2020 5:29 PM, Jerin Jacob wrote: > > > > > On Mon, Apr 27, 2020 at 9:42 PM Ferruh Yigit <[email protected]> > > > > > wrote: > > > > > > On 4/27/2020 10:19 AM, Dumitrescu, Cristian wrote: > > > > > > > > > > > > > > > -----Original Message----- > > > > > > > > From: Yigit, Ferruh <[email protected]> > > > > > > > > Sent: Saturday, April 25, 2020 9:09 PM > > > > > > > > To: Dumitrescu, Cristian <[email protected]>; > > > > > > > > Nithin Dabilpuram > > > > > > > > <[email protected]>; Singh, Jasvinder > > > > > > > > <[email protected]>; > > > > > > > > Thomas Monjalon <[email protected]>; Andrew Rybchenko > > > > > > > > <[email protected]> > > > > > > > > Cc: [email protected]; [email protected]; [email protected]; Nithin > > > > > > > > Dabilpuram <[email protected]> > > > > > > > > Subject: Re: [PATCH v4 1/4] ethdev: add tm support for shaper > > > > > > > > config in pkt > > > > > > > > mode > > > > > > > > > > > > > > > > On 4/24/2020 11:28 AM, Dumitrescu, Cristian wrote: > > > > > > > > > > > > > > > > > > > -----Original Message----- > > > > > > > > > > From: Nithin Dabilpuram <[email protected]> > > > > > > > > > > Sent: Wednesday, April 22, 2020 6:21 PM > > > > > > > > > > To: Singh, Jasvinder <[email protected]>; > > > > > > > > > > Dumitrescu, Cristian > > > > > > > > > > <[email protected]>; Thomas Monjalon > > > > > > > > > > <[email protected]>; Yigit, Ferruh > > > > > > > > > > <[email protected]>; Andrew > > > > > > > > > > Rybchenko <[email protected]> > > > > > > > > > > Cc: [email protected]; [email protected]; [email protected]; > > > > > > > > > > Nithin > > > > > > > > > > Dabilpuram <[email protected]> > > > > > > > > > > Subject: [PATCH v4 1/4] ethdev: add tm support for shaper > > > > > > > > > > config in pkt > > > > > > > > > > mode > > > > > > > > > > > > > > > > > > > > From: Nithin Dabilpuram <[email protected]> > > > > > > > > > > > > > > > > > > > > Some NIC hardware support shaper to work in packet mode i.e > > > > > > > > > > shaping or ratelimiting traffic is in packets per second > > > > > > > > > > (PPS) as > > > > > > > > > > opposed to default bytes per second (BPS). Hence this patch > > > > > > > > > > adds support to configure shared or private shaper in > > > > > > > > > > packet mode, > > > > > > > > > > provide rate in PPS and add related tm capabilities in > > > > > > > > > > port/level/node > > > > > > > > > > capability structures. > > > > > > > > > > > > > > > > > > > > This patch also updates tm port/level/node capability > > > > > > > > > > structures with > > > > > > > > > > exiting features of scheduler wfq packet mode, scheduler > > > > > > > > > > wfq byte mode > > > > > > > > > > and private/shared shaper byte mode. > > > > > > > > > > > > > > > > > > > > SoftNIC PMD is also updated with new capabilities. > > > > > > > > > > > > > > > > > > > > Signed-off-by: Nithin Dabilpuram <[email protected]> > > > > > > > > > > --- > > > > > > > > > > v3..v4: > > > > > > > > > > - Update text under packet_mode as per Cristian. > > > > > > > > > > - Update rte_eth_softnic_tm.c based on Jasvinder's comments. > > > > > > > > > > - Add error enum > > > > > > > > RTE_TM_ERROR_TYPE_SHAPER_PROFILE_PACKET_MODE > > > > > > > > > > - Fix shaper_profile_check() with packet mode check > > > > > > > > > > - Fix typo's > > > > > > > > > > > > > > > > > > > > > > > > > > > > Acked-by: Cristian Dumitrescu <[email protected]> > > > > > > > > > > > > > > > > > > > > > > > > > Hi Nithin, > > > > > > > > > > > > > > > > It looks like patch is causing ABI break, I am getting > > > > > > > > following warning [1], > > > > > > > > can you please check? > > > > > > > > > > > > > > > > [1] > > > > > > > > https://pastebin.com/XYNFg14u > > > > > > > > > > > > > > Hi Ferruh, > > > > > > > > > > > > > > The RTE_TM API is marked as experimental, but it looks that this > > > > > > > was not correctly marked when __rte_experimental ABI checker was > > > > > > > introduced. > > > > > > > > > > > > > > It is marked as experimental at the top of the rte_tm.h, > > > > > > > similarly to other APIs introduced around same time, but it was > > > > > > > not correctly picked up by the ABI check procedure when later > > > > > > > introduced, so __rte_experimental was not added to every function. > > > > > > > > > > > > > > > > > > > :( > > > > > > > > > > > > Is it time to mature them? > > > > > > > > > > > > As you said they are not marked as experimental both in header file > > > > > > (function > > > > > > declarations) and .map file. > > > > > > > > > > > > The problem is, they are not marked as experimental in DPDK_20.0 > > > > > > ABI (v19.11), > > > > > > so marking them as experimental now will break the ABI. Not sure > > > > > > what to do, > > > > > > cc'ed a few ABI related names for comment. > > > > > > > > > > > > For me, we need to proceed as the experimental tag removed and APIs > > > > > > become > > > > > > mature starting from v19.11, since this is what happened in > > > > > > practice, and remove > > > > > > a few existing being experimental references in the doxygen > > > > > > comments. > > > > > > > > > > I think, accidentally we can not make a library as NON-experimental. > > > > > TM never went through experimental to mature transition(see git log > > > > > lib/librte_ethdev/rte_tm.h) > > > > > It was a bug to not mark as experimental in each function in the ABI > > > > > process. > > > > > Some of the features like packet marking are not even implemented by > > > > > any HW. > > > > > I think, we can make API stable only all the features are implemented > > > > > by one or two HW. > > > > > > > > Fair enough, specially if the API is not ready yet. > > > > > > > > But they were part of stable ABI, and marking them as experimental now > > > > will > > > > break the old applications using these APIs. > > > > > > it is still marked as EXPERIMENTAL everywhere and API is not ready yet. > > > > Existing experimental marks are text only for human parsing. > > > > The compiler attribute and build time checks are missing, and the symbol in > > the > > binary doesn't have experimental tag. Our scripts and automated checks won't > > detect it as experimental. > > > > My point is just having experimental comment in header file is not enough to > > qualify the APIs as experimental. > > > > > Anyway, we need to break the ABI to make it work on various HW. > > > I am not sure what to do? > > > IMO, We need to send a patch as Fixes: for the bug of not adding > > > __rte_experimental in each function. > > > > Yes, this is where we are, both you and Cristian suggest API is not ready > > and > > should be experimental, but they were part of stable ABI, making them > > experimental will break the ABI. > > It looks like there is no good option but we should select one of the bad > > ones. > > > > > Traffic Management API - EXPERIMENTAL > > > M: Cristian Dumitrescu <[email protected]> > > > T: git://dpdk.org/next/dpdk-next-qos > > > F: lib/librte_ethdev/rte_tm* > > > > > > Ray, Neil, David, Luca, Kevin, what do you think? > While I'm not called any of those names, allow me to give my 2c. > > Since these are marked in binaries as part of the stable ABI, I think we > need to honour that for the next two releases 20.05 and 20.08 [which means > that we need to put in versioned functions for any changes, not that we > can't change anything] > > For 20.11, I think these should then have one of two options taken: > * have these "fixed" and ready to be marked as stable, and officially part > of v21 ABI or > * mark them as experimental properly, and look to have them as part of the > v22 or subsequent ABI > > Given the comments here, I would tend towards the latter of the above two > options, but that's really a decision for the maintainers. > > Remember, this is not the first bug we have encountered where we messed up > some ABI versions in the 19.11 release, and, like the previous one with the > screwed up version number, I think we need to honour the ABI committments > made, especially since in this case it's only for a few more months till > 20.11 development starts. > > /Bruce
+1 If they are not ready now, they haven't been ready for the past 6 months either, so staying not ready for 6 more is the lesser evil. -- Kind regards, Luca Boccassi

