> On 2/4/2015 6:29 PM, [email protected] wrote: > > From: Ira Weiny <[email protected]> > > > > OPA MADs share a common header with IBTA MADs but with a different > > base version and an extended length. These "jumbo" MADs increase the > > performance of management traffic. > > > > Sharing a common header with IBTA MADs allows us to share most of the > > MAD processing code when dealing with OPA MADs in addition to > > supporting some IBTA MADs on OPA devices. > > > > Add a device capability flag to indicate OPA MAD support on the device. > > > > Signed-off-by: Ira Weiny <[email protected]> > > > > --- > > include/rdma/ib_verbs.h | 5 +++++ > > 1 file changed, 5 insertions(+) > > > > diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h index > > 3ab4033..2614233 100644 > > --- a/include/rdma/ib_verbs.h > > +++ b/include/rdma/ib_verbs.h > > @@ -128,6 +128,10 @@ enum ib_device_cap_flags { > > IB_DEVICE_ON_DEMAND_PAGING = (1<<31), > > }; > > > > +enum ib_device_cap_flags2 { > > + IB_DEVICE_OPA_MAD_SUPPORT = 1 > > +}; > > + > > enum ib_signature_prot_cap { > > IB_PROT_T10DIF_TYPE_1 = 1, > > IB_PROT_T10DIF_TYPE_2 = 1 << 1, > > @@ -210,6 +214,7 @@ struct ib_device_attr { > > int sig_prot_cap; > > int sig_guard_cap; > > struct ib_odp_caps odp_caps; > > + u64 device_cap_flags2; > > u32 max_mad_size; > > }; > > > > Why is OPA support determined via a device capability flag ? What are the > tradeoffs for doing it this way versus the other choices that have been used > in > the past for other RDMA technologies like RoCE, iWARP, usNIC, ... ?
None of those technologies use the MAD stack for Subnet Management. Other MAD support is very limited (ie IB compatible PMA queries on the local port only). Do you have a suggestion for alternatives? Ira -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
