From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Netes Subject: Re: [PATCH 0/8] opensm: Improved mkey support Date: Mon, 23 Jul 2012 18:59:07 +0300 Message-ID: <20120723155907.GC2064@calypso> References: <1340672058.5218.97.camel@auk75.llnl.gov> <1341361508.5218.148.camel@auk75.llnl.gov> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1341361508.5218.148.camel-mxTxeWJot8FliZ7u+bvwcg@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Jim Foraker Cc: linux-rdma , "Weiny, Ira K." List-Id: linux-rdma@vger.kernel.org Hi Jim, Can you please add short description of the improved M_Key mechanism into the man page? On 17:25 Tue 03 Jul , Jim Foraker wrote: > I'm sending new versions of patches 1 and 3 to the list, which > correct merge/build issues introduced by other recently accepted > patches. They will be marked as "V1.1". > > Jim > > On Mon, 2012-06-25 at 17:54 -0700, Jim Foraker wrote: > > I'm about to post a set of patches intended to improve mkey support > > in OpenSM. These patches have been fairly rigorously tested on a small > > fabric, and I believe are sufficiently stable for inclusion. The > > primary intent here is threefold: > > > > 1) Fix a multitude of edge case issues with the existing > > single-mkey-per-subnet support in OpenSM. For instance, the current > > implementation provides no way to change an established non-zero mkey > > without rebooting or manually re-keying each CA on the entire subnet. > > > > 2) Enable mkey protection across the fabric. This involves not only > > setting a non-zero protection level, but also providing the SM with a > > sufficient information cache to initialize the subnet on restart without > > having to wait for mkey lease timeouts (provided one is set). > > > > 3) Provide a basis on which to build multiple-mkey systems for OpenSM > > (be they per-host, KDF, or random) in the future. > > > > The patches add two new cache files: a port guid-to-mkey cache, and > > a neighboring link (port guid to port guid) cache. > > The guid2mkey cache is used to provide a hint at the initial mkey > > for a CA during initialization. It is a hint only; the SM is capable of > > dealing with cases where the guid2mkey cache is incorrect, although it > > may require waiting for (potentially multiple) mkey lease timeouts at > > non-zero mkey protection levels. The guid2mkey cache is presented first > > in the patch set, as it ends up ameliorating several corner cases in a > > cleaner way than attacking them directly did. > > The neighbors cache file provides an initial hint to the SM of what > > port guid we may expect at the opposite end of a link that is being > > initialized. This is necessary at mkey protection level 2, where we > > cannot do the SubnGet necessary to determine the port guid to use in > > looking up an mkey hint. > > The changes to the osm_req functions to support mkeys in patch 2 > > now require plock to be held when called. This was generally already > > the case, but there were a few spots where it was not. In most of these > > cases, the plock is still not technically necessary, as they occur > > during hops 0/1 when DR path traversal is trivial. I wrapped all of > > these occurrences in locks in a separate patch (#3), in order to make > > the changes more obvious and invite comment. > > > > Jim > > -- > 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 -- 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