On Sun, May 13, 2012 at 02:32:29PM -0400, David Miller wrote: > From: Sam Ravnborg <sam@xxxxxxxxxxxx> > Date: Sun, 13 May 2012 14:16:00 +0200 > > > I could try to come up with something myself - but if we already > > have it somewhere maybe there is something to be inspired by. > > You could relocatable link, record all the R_SPARC_WDISP30 relocations > into a special data file (which you'd link into vmlinux), then provide > a stub version of all the routines. > > At run time you walk through the relocations and resolve them just as > the linker or the module loader would. > > But I wouldn't do this, it's hairy with modules etc. > > Instead, I'd do for these routines what sparc64 does, which is patch > the actual code. > > You have a base implementation which is at least as large as the > largest implementation which exists. Then you simply copy the > instructions over from the implementation you want to use. All > branches must be relative and be to destination only within the > routine itself, otherwise you'd have to fixup their offsets since the > necessary branch displacement changes once you move the instruction > from one place to another. That makes sense - then we do not need to search for the callers etc. And we can use the base implemntation as the default case. But I need to brush up my sparc assembler skills a bit first, I'm afraid. I will put this on my todo list as this would be good to have, but I will postpone the idea for now. Sam -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
