diff options
| -rw-r--r-- | kernel/trace/ftrace.c | 68 |
1 files changed, 34 insertions, 34 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 58839d9a3b8b..d40d7f6f3c51 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -259,9 +259,6 @@ static int remove_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) static int __register_ftrace_function(struct ftrace_ops *ops) { - if (ftrace_disabled) - return -ENODEV; - if (FTRACE_WARN_ON(ops == &global_ops)) return -EINVAL; @@ -290,9 +287,6 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops) { int ret; - if (ftrace_disabled) - return -ENODEV; - if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED))) return -EBUSY; @@ -1703,10 +1697,15 @@ static void ftrace_startup_enable(int command) static int ftrace_startup(struct ftrace_ops *ops, int command) { bool hash_enable = true; + int ret; if (unlikely(ftrace_disabled)) return -ENODEV; + ret = __register_ftrace_function(ops); + if (ret) + return ret; + ftrace_start_up++; command |= FTRACE_UPDATE_CALLS; @@ -1728,12 +1727,17 @@ static int ftrace_startup(struct ftrace_ops *ops, int command) return 0; } -static void ftrace_shutdown(struct ftrace_ops *ops, int command) +static int ftrace_shutdown(struct ftrace_ops *ops, int command) { bool hash_disable = true; + int ret; if (unlikely(ftrace_disabled)) - return; + return -ENODEV; + + ret = __unregister_ftrace_function(ops); + if (ret) + return ret; ftrace_start_up--; /* @@ -1768,9 +1772,10 @@ static void ftrace_shutdown(struct ftrace_ops *ops, int command) } if (!command || !ftrace_enabled) - return; + return 0; ftrace_run_update_code(command); + return 0; } static void ftrace_startup_sysctl(void) @@ -2622,16 +2627,13 @@ static void __enable_ftrace_function_probe(void) if (i == FTRACE_FUNC_HASHSIZE) return; - ret = __register_ftrace_function(&trace_probe_ops); - if (!ret) - ret = ftrace_startup(&trace_probe_ops, 0); + ret = ftrace_startup(&trace_probe_ops, 0); ftrace_probe_registered = 1; } static void __disable_ftrace_function_probe(void) { - int ret; int i; if (!ftrace_probe_registered) @@ -2644,9 +2646,7 @@ static void __disable_ftrace_function_probe(void) } /* no more funcs left */ - ret = __unregister_ftrace_function(&trace_probe_ops); - if (!ret) - ftrace_shutdown(&trace_probe_ops, 0); + ftrace_shutdown(&trace_probe_ops, 0); ftrace_probe_registered = 0; } @@ -3619,12 +3619,15 @@ device_initcall(ftrace_nodyn_init); static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; } static inline void ftrace_startup_enable(int command) { } /* Keep as macros so we do not need to define the commands */ -# define ftrace_startup(ops, command) \ - ({ \ - (ops)->flags |= FTRACE_OPS_FL_ENABLED; \ - 0; \ +# define ftrace_startup(ops, command) \ + ({ \ + int ___ret = __register_ftrace_function(ops); \ + if (!___ret) \ + (ops)->flags |= FTRACE_OPS_FL_ENABLED; \ + ___ret; \ }) -# define ftrace_shutdown(ops, command) do { } while (0) +# define ftrace_shutdown(ops, command) __unregister_ftrace_function(ops) + # define ftrace_startup_sysctl() do { } while (0) # define ftrace_shutdown_sysctl() do { } while (0) @@ -3964,15 +3967,8 @@ int register_ftrace_function(struct ftrace_ops *ops) mutex_lock(&ftrace_lock); - if (unlikely(ftrace_disabled)) - goto out_unlock; - - ret = __register_ftrace_function(ops); - if (!ret) - ret = ftrace_startup(ops, 0); - + ret = ftrace_startup(ops, 0); - out_unlock: mutex_unlock(&ftrace_lock); return ret; } @@ -3989,9 +3985,7 @@ int unregister_ftrace_function(struct ftrace_ops *ops) int ret; mutex_lock(&ftrace_lock); - ret = __unregister_ftrace_function(ops); - if (!ret) - ftrace_shutdown(ops, 0); + ret = ftrace_shutdown(ops, 0); mutex_unlock(&ftrace_lock); return ret; @@ -4185,6 +4179,12 @@ ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state, return NOTIFY_DONE; } +/* Just a place holder for function graph */ +static struct ftrace_ops fgraph_ops __read_mostly = { + .func = ftrace_stub, + .flags = FTRACE_OPS_FL_GLOBAL, +}; + int register_ftrace_graph(trace_func_graph_ret_t retfunc, trace_func_graph_ent_t entryfunc) { @@ -4211,7 +4211,7 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc, ftrace_graph_return = retfunc; ftrace_graph_entry = entryfunc; - ret = ftrace_startup(&global_ops, FTRACE_START_FUNC_RET); + ret = ftrace_startup(&fgraph_ops, FTRACE_START_FUNC_RET); out: mutex_unlock(&ftrace_lock); @@ -4228,7 +4228,7 @@ void unregister_ftrace_graph(void) ftrace_graph_active--; ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; ftrace_graph_entry = ftrace_graph_entry_stub; - ftrace_shutdown(&global_ops, FTRACE_STOP_FUNC_RET); + ftrace_shutdown(&fgraph_ops, FTRACE_STOP_FUNC_RET); unregister_pm_notifier(&ftrace_suspend_notifier); unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |