From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roland Dreier Subject: Re: [PATCH] IB/mlx4: fix post_recv wq overflow check Date: Tue, 19 Jan 2010 08:13:35 -0800 Message-ID: References: <4B45913C.10405@Voltaire.com> <4B45A2E5.2070301@voltaire.com> <4B55D441.5050000@voltaire.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: In-Reply-To: <4B55D441.5050000-smomgflXvOZWk0Htik3J/w@public.gmane.org> (Or Gerlitz's message of "Tue, 19 Jan 2010 17:48:17 +0200") Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Or Gerlitz Cc: linux-rdma , Jack Morgenstein List-Id: linux-rdma@vger.kernel.org > mmm, why is that common? typically there's a higher layer to which the > IB ULP advertises some sort of maximal number of credits (e.g in the > SCSI case, iser and srp specify the maximal number of commands in the > scsi host template) or the ULP informs a higher layer that no more > sends can be done (e.g IPoIB calling netif_stop_queue once it sense > that the QP filled, etc). bugs in the ULP. And it seems to be a common kind of bug. In other words this check catches common bugs and makes them a gazillion times easier to find and fix. So unless the performance impact is extreme, I'm inclined to leave it. - R. -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html