I did not understand the relation between ops.poll_cq() and ibv_cmd_poll_cq() correctly.
It is clear now. Thank you. --CQ > -----Original Message----- > From: Roland Dreier [mailto:[email protected]] > Sent: Wednesday, September 02, 2009 6:09 PM > To: Tang, Changqing > Cc: Sean Hefty; [email protected]; > [email protected] > Subject: Re: [ofa-general] performance to call ibv_poll_cq() > vs. call select() on completion channel > > > > I understand that ops.poll_cq is actually > ibv_cmd_poll_cq(), right ? > > No, not for most devices. Look at libmthca, etc to see what > the poll_cq method is set to. > > > Do you mean during ibv_poll_cq() call, there is no > system call involved ? > > Right, for most devices poll_cq can be done just by looking > at memory in userspace without involving the kernel at all. > _______________________________________________ general mailing list [email protected] http://lists.openfabrics.org/cgi-bin/mailman/listinfo/general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
