On Thu, May 24, 2012 at 1:07 AM, Ursula Braun <[email protected]> wrote: > we want to make use of Infiniband communication and I am working on the > Linux part. The peer can be a non-Linux system. Now we see a mismatch in > the size of the queue pair number in Linux (32 bits) and the Infiniband > Architecture Specification (24 bits). Will the additional 8 highest > order bits ever be used in Linux? And if yes, for which purpose? Is the > maximum queue pair number 0xFFFFFF?
The reason the queue pair number type is 32 bits in the Linux stack is that there is no u24 or uint24_t and very few processors have support for 24-bit integer types :) The queue pair numbers are allocated by the hardware drivers, and modulo bugs they should always return a QPN that complies with the IB architecture. So in other words, yes, you can safely assume that QPNs are in the range 0 ... 0xffffff. - R. -- 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
