On Wed, Mar 31, 2010 at 8:18 PM, Roland Dreier <rdre...@cisco.com> wrote: > > > The SRP initiator works fine without this patch, and this patch slows > > down the SRP initiator. > > I do agree that there are no missed callbacks without this patch, but I > don't see how it would slow things down... it seems to me it would avoid > some CQ event callbacks, especially for HCAs where > IB_CQ_REPORT_MISSED_EVENTS never returns >0 for missed events.
Processing the flag IB_CQ_REPORT_MISSED_EVENTS causes several IB drivers to lock and unlock a spinlock. Full-speed SRP I/O can cause this operation to be invoked more than 100.000 times a second, so the flag IB_CQ_REPORT_MISSED_EVENTS will have a small but measurable impact on SRP I/O performance. Bart. -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
