On Mon, Oct 20, 2008 at 12:30:33PM -0400, Steven Rostedt wrote: >> Anyway, if you want a tester let me know. It seems 2.6.27.1 should be >> fine since FTRACE was disabled, but for .28-rc1 it would be cool if it >> worked :). > >Hi Josh, > >I've been looking deeper at the code for PPC. I realized that my PPC64 box >that I've been testing on did not use modules. While looking at the module >code it dawned on me the dynamic ftrace needs a bit of work. This is >because the way modules are handled in PPC (and other architectures as >well). The jmps used by mcount is a 24 bit jump. Since the modules are >loaded farther than 24bits away, a trampoline is needed.
Ah, indeed. >A bit of rework is needed in the ftrace infrastructure to handle the >trampoline. Too much work to go into 28. I'll start working on code that >can hopefully be ready and tested for 29. It's not that major of a change, >but since the merge window for 28 has already been opened, we would like >to get a bit more testing in before we hand it over to Linus. That seems like a good plan. Should we mark dynamic ftrace as X86 only in Kconfig for .28 to prevent people from inadvertently setting it? josh _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
