On 10/5/2018 12:30 PM, Neil Horman wrote: > On Fri, Oct 05, 2018 at 11:17:30AM +0100, Ferruh Yigit wrote: >> On 10/5/2018 10:13 AM, Bruce Richardson wrote: >>> On Thu, Oct 04, 2018 at 05:55:34PM +0200, Thomas Monjalon wrote: >>>> 04/10/2018 17:28, Ferruh Yigit: >>>>> On 10/4/2018 4:10 PM, Thomas Monjalon wrote: >>>>>> 04/10/2018 17:48, Ferruh Yigit: >>>>>>> Enabling RTE_NEXT_ABI means to enable APIs that break the ABI for >>>>>>> the current release and these APIs are targeted for further release. >>>>>> >>>>>> It seems nobody is using it in last releases. >>>>>> >>>>>>> RTE_NEXT_ABI shouldn't be enabled by default. >>>>>> >>>>>> The reason for having it enabled by default is that when you build DPDK >>>>>> yourself, you probably want the latest features. >>>>>> If packaged properly for stability, it is easy to disable it in >>>>>> the package recipe. >>>>> >>>>> My concern was (if this has been used), user may get unstable APIs and >>>>> without >>>>> explicitly being aware of it. >>>> >>>> I am OK with both defaults (enabled or disabled). >>>> >>> I'd keep it as is. As said, I'm not sure it's being used right now anyway. >> >> No, not used right now. >> But I think we can use it, did you able to find chance to check: >> >> https://mails.dpdk.org/archives/dev/2018-October/114372.html >> >> Option D. >> > > Just to propose something else, We also have the ALLOW_EXPERIMENTAL_API flag > that we IIRC default to on. Would it be worth consolidating these two > mechanisms into one? Currently ALLOW_EXPERIMENTAL_API lets us flag symbols > that > are not yet stable, and it seems to work well. It does not however let us > simply define out structures/variables that might adversely affect the ABI. > Would it be worth considering adding a macro (something like > __rte_experimental_symbol()), that allows a variable/struct to be defined if > ALLOW_EXPERIMENTAL_API is set, and squashed otherwise?
RTE_NEXT_ABI is not just for symbols. If there a new API foo(), __rte_experimental works fine to mark it experimental. But if there is an _existing API_ "bar(char)", and we plan to change it to "bar(int, int)", to publish the change early in this release we need RTE_NEXT_ABI ifdef since both can't exist together, so it will be used as: Release N: #ifdef RTE_NEXT_ABI bar(int, int); #else bar(char); #endif Release N + 1: bar(int, int);
