diff options
Diffstat (limited to 'arch/loongarch/kernel/ftrace_dyn.c')
| -rw-r--r-- | arch/loongarch/kernel/ftrace_dyn.c | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/arch/loongarch/kernel/ftrace_dyn.c b/arch/loongarch/kernel/ftrace_dyn.c index 3b82bface840..5a801c328e2a 100644 --- a/arch/loongarch/kernel/ftrace_dyn.c +++ b/arch/loongarch/kernel/ftrace_dyn.c @@ -108,3 +108,47 @@ int __init ftrace_dyn_arch_init(void) { return 0; } + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent) +{ + unsigned long old; + unsigned long return_hooker = (unsigned long)&return_to_handler; + + if (unlikely(atomic_read(¤t->tracing_graph_pause))) + return; + + old = *parent; + + if (!function_graph_enter(old, self_addr, 0, NULL)) + *parent = return_hooker; +} + +static int ftrace_modify_graph_caller(bool enable) +{ + u32 branch, nop; + unsigned long pc, func; + extern void ftrace_graph_call(void); + + pc = (unsigned long)&ftrace_graph_call; + func = (unsigned long)&ftrace_graph_caller; + + nop = larch_insn_gen_nop(); + branch = larch_insn_gen_b(pc, func); + + if (enable) + return ftrace_modify_code(pc, nop, branch, true); + else + return ftrace_modify_code(pc, branch, nop, true); +} + +int ftrace_enable_ftrace_graph_caller(void) +{ + return ftrace_modify_graph_caller(true); +} + +int ftrace_disable_ftrace_graph_caller(void) +{ + return ftrace_modify_graph_caller(false); +} +#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |