diff options
Diffstat (limited to 'arch/powerpc/kernel/entry_32.S')
| -rw-r--r-- | arch/powerpc/kernel/entry_32.S | 43 |
1 files changed, 42 insertions, 1 deletions
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S index fd54cb59728..12247b937d2 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S @@ -1199,9 +1199,11 @@ _GLOBAL(_mcount) mtctr r5 bctrl - nop +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + b ftrace_graph_caller +#endif MCOUNT_RESTORE_FRAME bctr @@ -1210,4 +1212,43 @@ _GLOBAL(_mcount) _GLOBAL(ftrace_stub) blr +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +_GLOBAL(ftrace_graph_caller) + /* load r4 with local address */ + lwz r4, 44(r1) + subi r4, r4, MCOUNT_INSN_SIZE + + /* get the parent address */ + addi r3, r1, 52 + + bl prepare_ftrace_return + nop + + MCOUNT_RESTORE_FRAME + /* old link register ends up in ctr reg */ + bctr + +_GLOBAL(return_to_handler) + /* need to save return values */ + stwu r1, -32(r1) + stw r3, 20(r1) + stw r4, 16(r1) + stw r31, 12(r1) + mr r31, r1 + + bl ftrace_return_to_handler + nop + + /* return value has real return address */ + mtlr r3 + + lwz r3, 20(r1) + lwz r4, 16(r1) + lwz r31,12(r1) + lwz r1, 0(r1) + + /* Jump back to real return address */ + blr +#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ + #endif /* CONFIG_MCOUNT */ |