From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Gunthorpe Subject: Re: [PATCH 11/12] IB/core: add RW API support for signature MRs Date: Tue, 19 Apr 2016 11:26:27 -0600 Message-ID: <20160419172627.GC20844@obsidianresearch.com> References: <1461010463-6603-1-git-send-email-hch@lst.de> <1461010463-6603-12-git-send-email-hch@lst.de> <57163E99.8090301@grimberg.me> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <57163E99.8090301@grimberg.me> Sender: target-devel-owner@vger.kernel.org To: Sagi Grimberg Cc: Christoph Hellwig , dledford@redhat.com, bart.vanassche@sandisk.com, swise@opengridcomputing.com, linux-rdma@vger.kernel.org, target-devel@vger.kernel.org List-Id: linux-rdma@vger.kernel.org On Tue, Apr 19, 2016 at 05:20:09PM +0300, Sagi Grimberg wrote: > In isert if the we have a single sg entry, we use the local_dma_lkey > just so we can skip a registration (also for protection sg), perhaps > rdma_rw_init_one_mr can do this optimization too? Can't more than a single SG can be packed into a WR? Ideally this common code should try and max out the SG entries before falling back to using a WR? There is probably an interesting performance trade off around making the WR SG list bigger vs using the MR. But that could be done as a follow up patch... This series is a big, big improvement already. Jason