2017-01-30 13:38, Aaron Conole: > Stephen Hemminger <step...@networkplumber.org> writes: > > Bruce Richardson <bruce.richard...@intel.com> wrote: > >> On Fri, Jan 27, 2017 at 08:33:46AM -0800, Stephen Hemminger wrote: > >> > Why use rte_errno? > >> > Most DPDK calls just return negative value on error which > >> > corresponds to error number. > >> > Are you trying to keep ABI compatibility? Doesn't make sense > >> > because before all these > >> > errors were panic's no working application is going to care. > >> > >> Either will work, but I actually prefer this way. I view using rte_errno > >> to be better as it can work in just about all cases, including with > >> functions which return pointers. This allows you to have a standard > >> method across all functions for returning error codes, and it only > >> requires a single sentinal value to indicate error, rather than using a > >> whole range of values. > > > > The problem is DPDK is getting more inconsistent on how this is done. > > As long as error returns are always same as kernel/glibc errno's it really > > doesn't > > matter much which way the value is returned from a technical point of view > > but the inconsistency is sure to be a usability problem and source of > > errors. > > I am using rte_errno here because I assumed it was the preferred > method. In fact, looking at some recently contributed modules (for > instance pdump), it seems that folks are using it. > > I'm not really sure the purpose of having rte_errno if it isn't used, so > it'd be helpful to know if there's some consensus on reflecting errors > via this variable, or on returning error codes. Whichever is the more > consistent with the way the DPDK project does things, I'm game :).
I think we can use both return value and rte_errno. We could try to enforce rte_errno as mandatory everywhere. Adrien did the recent rte_flow API. Please Adrien, could you give your thought?
