Le 05/09/2012 17:40, Jeff Squyres a écrit : > I agree -- all of the things you mention are do-able. > > But it's a whole lot more bookkeeping and care/feeding to ensure that nothing > goes wrong vs. just calling a hwloc core function and assuming it's there. > Such things will require maintenance over time. > > In the end -- it's a tradeoff: > > - do we want the maintenance associated with a struct full of core function > pointers? > > or > > - do we want to use the solution I mentioned in > http://www.open-mpi.org/community/lists/hwloc-devel/2012/09/3253.php?
It may even be easier in hwloc since plugins are disabled by default. We may just need to forbid --enable-static and --enabled-plugins simultaneously. Did anybody ever complained about shared+static not being allowed simultaneously in OMPI? Brice > > Both have strengths / weaknesses. > > > > On Sep 5, 2012, at 11:25 AM, Samuel Thibault wrote: > >> Jeff Squyres, le Wed 05 Sep 2012 17:13:56 +0200, a écrit : >>>> The source code shouldn't need to be modified: >>>> >>>> #define hwloc_foo_bar(arg1, arg2) hwloc_funcs->foo_bar(arg1, arg2) >>> You need to make sure that #define is only effected in certain places in >>> the code. >> Well, all the places that will constitute a plugin, no? >> >>> And you need to ensure that hwloc_funcs->[foo] isn't attempted to be used >>> before it has been filled in. >> As I said in my earlier mail, hwloc_funcs would be provided by the >> loader of the plugin, so it can make sure it's filled in (I forgot to >> mention that what I call hwloc_funcs above is an internal variable of >> the plugin, not a symbol provided by libhwloc.so). >> >>> And unless there is a very fixed set of functions that can be called by >>> plugins, >> Well, I believe we'll have to have that anyway. That was part of the >> whole discussion about plugins a long time ago. >> >>> you'll probably need to grow hwloc_funcs over time, which may lead to ABI >>> issues...? >> Sure. We can for instance make the plugin check for the size of >> hwloc_funcs provided by the plugin loader vs the size that it was >> compiled against, and thus refuse to get loaded by an older hwloc. >> >> Samuel >> _______________________________________________ >> hwloc-devel mailing list >> hwloc-de...@open-mpi.org >> http://www.open-mpi.org/mailman/listinfo.cgi/hwloc-devel >
