From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Monjalon Subject: Re: [PATCH] mk: fix missing link of librte_vhost in shared, non-combined config Date: Fri, 13 Feb 2015 14:18:48 +0100 Message-ID: <4225678.HUzObN4r7D@xps13> References: <6ca22ee1257e34ee2b89f2fb354d6c382b8f3e29.1423644785.git.pmatilai@redhat.com> <12066921.2HzVPH8BW6@xps13> <54DDD2EE.7070505@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: dev-VfR2kkLFssw@public.gmane.org To: Panu Matilainen Return-path: In-Reply-To: <54DDD2EE.7070505-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces-VfR2kkLFssw@public.gmane.org Sender: "dev" 2015-02-13 12:33, Panu Matilainen: > On 02/13/2015 11:28 AM, Thomas Monjalon wrote: > > 2015-02-13 09:27, Panu Matilainen: > >> On 02/12/2015 05:44 PM, Thomas Monjalon wrote: > >>> A library is considered as a plugin if there is no public API and it > >>> registers itself. That's the case of normal PMD. > >>> But bonding and Xen have some library parts with public API. > >>> It has been discussed and agreed for bonding but I'm not aware of the Xen case. > >> > >> Fair enough, thanks for the explanation. > >> > >> Just wondering about versioning of these things - currently all the PMDs > >> are versioned as well, which is slightly at odds with their expected > >> usage, dlopen()'ed items usually are not versioned because it makes the > >> files moving targets. But if a plugin can be an library too then it > >> clearly needs to be versioned as well. > > > > Not sure to understand your considerations. > > Plugins must be versioned because there can be some incompatibilities > > like mbuf rework. > > Plugins are version-dependent obviously, but the issue is somewhat > different from library versioning. Plugins are generally consumers of > the versioned ABIs, whereas libraries are the providers. > > >> I'm just thinking of typical packaging where the unversioned *.so > >> symlinks are in a -devel subpackage and the versioned libraries are in > >> the main runtime package. Plugins should be loadable by a stable > >> unversioned name always, for libraries the linker handles it behind the > >> scenes. So in packaging these things, plugin *.so links need to be > >> handled differently (placed into the main package) from others. Not > >> rocket science to filter by 'pmd' in the name, but a new twist anyway > >> and easy to get wrong. > >> > >> One possibility to make it all more obvious might be having a separate > >> directory for plugins, the mixed case ccould be handled by symlinks. > > > > I think I don't understand which use case you are trying to solve. > > Its a usability/documentation issue more than a technical one. If plugin > DSO's are versioned (like they currently are), then loading them via eg > -d becomes cumbersome since you need to hunt down and provide the > versioned name, eg "testpmd -d librte_pmd_pcap.so.1 [...]" > > Like said above, it can be worked around by leaving the unversioned > symlinks in place for plugins in runtime (library) packages, but that > sort of voids the point of versioning. One possibility would be > introducing a per-version plugin directory that would be used as the > default path for dlopen() unless an absolute path is used. It makes me think that instead of using a -d option per plugin, why not adding a -D option to load all plugins from a directory?