On Tue, 2016-19-07 at 04:48:30 UTC, Michael Ellerman wrote: > In __ftrace_make_nop() (the 64-bit version), we have code to deal with > two ftrace ABIs. There is the original ABI, which looks mostly like a > function call, and then the mprofile-kernel ABI which is just a branch. > > The code tries to handle both cases, by looking for the presence of a > load to restore the TOC pointer (PPC_INST_LD_TOC). If we detect the TOC > load, we assume the call site is for an mcount() call using the old ABI. > That means we patch the mcount() call with a b +8, to branch over the > TOC load. > > However if the kernel was built with mprofile-kernel, then there will > never be a call site using the original ftrace ABI. If for some reason > we do see a TOC load, then it's there for a good reason, and we should > not jump over it. > > So split the code, using the existing CC_USING_MPROFILE_KERNEL. Kernels > built with mprofile-kernel will only look for, and expect, the new ABI, > and similarly for the original ABI. > > Signed-off-by: Michael Ellerman <m...@ellerman.id.au>
Applied to powerpc next. https://git.kernel.org/powerpc/c/9d636109511a000882f8dff4ea cheers _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
