diff options
Diffstat (limited to 'arch/powerpc')
| -rw-r--r-- | arch/powerpc/kernel/ftrace.c | 35 |
1 files changed, 18 insertions, 17 deletions
diff --git a/arch/powerpc/kernel/ftrace.c b/arch/powerpc/kernel/ftrace.c index 7af6c4de044b..cc52d9795f88 100644 --- a/arch/powerpc/kernel/ftrace.c +++ b/arch/powerpc/kernel/ftrace.c @@ -144,6 +144,21 @@ __ftrace_make_nop(struct module *mod, return -EINVAL; } +#ifdef CC_USING_MPROFILE_KERNEL + /* When using -mkernel_profile there is no load to jump over */ + pop = PPC_INST_NOP; + + if (probe_kernel_read(&op, (void *)(ip - 4), 4)) { + pr_err("Fetching instruction at %lx failed.\n", ip - 4); + return -EFAULT; + } + + /* We expect either a mflr r0, or a std r0, LRSAVE(r1) */ + if (op != PPC_INST_MFLR && op != PPC_INST_STD_LR) { + pr_err("Unexpected instruction %08x around bl _mcount\n", op); + return -EINVAL; + } +#else /* * Our original call site looks like: * @@ -170,24 +185,10 @@ __ftrace_make_nop(struct module *mod, } if (op != PPC_INST_LD_TOC) { - unsigned int inst; - - if (probe_kernel_read(&inst, (void *)(ip - 4), 4)) { - pr_err("Fetching instruction at %lx failed.\n", ip - 4); - return -EFAULT; - } - - /* We expect either a mlfr r0, or a std r0, LRSAVE(r1) */ - if (inst != PPC_INST_MFLR && inst != PPC_INST_STD_LR) { - pr_err("Unexpected instructions around bl _mcount\n" - "when enabling dynamic ftrace!\t" - "(%08x,bl,%08x)\n", inst, op); - return -EINVAL; - } - - /* When using -mkernel_profile there is no load to jump over */ - pop = PPC_INST_NOP; + pr_err("Expected %08x found %08x\n", PPC_INST_LD_TOC, op); + return -EINVAL; } +#endif /* CC_USING_MPROFILE_KERNEL */ if (patch_instruction((unsigned int *)ip, pop)) { pr_err("Patching NOP failed.\n"); |