diff options
| -rw-r--r-- | kernel/trace/trace_events.c | 103 |
1 files changed, 38 insertions, 65 deletions
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 86db6ee6f26c..047d2775184b 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -1546,19 +1546,18 @@ event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt, if (ret) return ret; + guard(mutex)(&event_mutex); + switch (val) { case 0: case 1: - mutex_lock(&event_mutex); file = event_file_file(filp); - if (likely(file)) { - ret = tracing_update_buffers(file->tr); - if (ret >= 0) - ret = ftrace_event_enable_disable(file, val); - } else { - ret = -ENODEV; - } - mutex_unlock(&event_mutex); + if (!file) + return -ENODEV; + ret = tracing_update_buffers(file->tr); + if (ret < 0) + return ret; + ret = ftrace_event_enable_disable(file, val); if (ret < 0) return ret; break; @@ -2145,7 +2144,7 @@ event_pid_write(struct file *filp, const char __user *ubuf, if (ret < 0) return ret; - mutex_lock(&event_mutex); + guard(mutex)(&event_mutex); if (type == TRACE_PIDS) { filtered_pids = rcu_dereference_protected(tr->filtered_pids, @@ -2161,7 +2160,7 @@ event_pid_write(struct file *filp, const char __user *ubuf, ret = trace_pid_write(filtered_pids, &pid_list, ubuf, cnt); if (ret < 0) - goto out; + return ret; if (type == TRACE_PIDS) rcu_assign_pointer(tr->filtered_pids, pid_list); @@ -2186,11 +2185,7 @@ event_pid_write(struct file *filp, const char __user *ubuf, */ on_each_cpu(ignore_task_cpu, tr, 1); - out: - mutex_unlock(&event_mutex); - - if (ret > 0) - *ppos += ret; + *ppos += ret; return ret; } @@ -3257,13 +3252,13 @@ int trace_add_event_call(struct trace_event_call *call) int ret; lockdep_assert_held(&event_mutex); - mutex_lock(&trace_types_lock); + guard(mutex)(&trace_types_lock); ret = __register_event(call, NULL); - if (ret >= 0) - __add_event_to_tracers(call); + if (ret < 0) + return ret; - mutex_unlock(&trace_types_lock); + __add_event_to_tracers(call); return ret; } EXPORT_SYMBOL_GPL(trace_add_event_call); @@ -3517,30 +3512,21 @@ struct trace_event_file *trace_get_event_file(const char *instance, return ERR_PTR(ret); } - mutex_lock(&event_mutex); + guard(mutex)(&event_mutex); file = find_event_file(tr, system, event); if (!file) { trace_array_put(tr); - ret = -EINVAL; - goto out; + return ERR_PTR(-EINVAL); } /* Don't let event modules unload while in use */ ret = trace_event_try_get_ref(file->event_call); if (!ret) { trace_array_put(tr); - ret = -EBUSY; - goto out; + return ERR_PTR(-EBUSY); } - ret = 0; - out: - mutex_unlock(&event_mutex); - - if (ret) - file = ERR_PTR(ret); - return file; } EXPORT_SYMBOL_GPL(trace_get_event_file); @@ -3778,12 +3764,11 @@ event_enable_func(struct trace_array *tr, struct ftrace_hash *hash, event = strsep(¶m, ":"); - mutex_lock(&event_mutex); + guard(mutex)(&event_mutex); - ret = -EINVAL; file = find_event_file(tr, system, event); if (!file) - goto out; + return -EINVAL; enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; @@ -3792,19 +3777,14 @@ event_enable_func(struct trace_array *tr, struct ftrace_hash *hash, else ops = param ? &event_disable_count_probe_ops : &event_disable_probe_ops; - if (glob[0] == '!') { - ret = unregister_ftrace_function_probe_func(glob+1, tr, ops); - goto out; - } - - ret = -ENOMEM; + if (glob[0] == '!') + return unregister_ftrace_function_probe_func(glob+1, tr, ops); if (param) { number = strsep(¶m, ":"); - ret = -EINVAL; if (!strlen(number)) - goto out; + return -EINVAL; /* * We use the callback data field (which is a pointer) @@ -3812,20 +3792,19 @@ event_enable_func(struct trace_array *tr, struct ftrace_hash *hash, */ ret = kstrtoul(number, 0, &count); if (ret) - goto out; + return ret; } /* Don't let event modules unload while probe registered */ ret = trace_event_try_get_ref(file->event_call); - if (!ret) { - ret = -EBUSY; - goto out; - } + if (!ret) + return -EBUSY; ret = __ftrace_event_enable_disable(file, 1, 1); if (ret < 0) goto out_put; + ret = -ENOMEM; data = kzalloc(sizeof(*data), GFP_KERNEL); if (!data) goto out_put; @@ -3840,23 +3819,20 @@ event_enable_func(struct trace_array *tr, struct ftrace_hash *hash, * but if it didn't find any functions it returns zero. * Consider no functions a failure too. */ - if (!ret) { - ret = -ENOENT; - goto out_disable; - } else if (ret < 0) - goto out_disable; + /* Just return zero, not the number of enabled functions */ - ret = 0; - out: - mutex_unlock(&event_mutex); - return ret; + if (ret > 0) + return 0; - out_disable: kfree(data); + + if (!ret) + ret = -ENOENT; + __ftrace_event_enable_disable(file, 0, 1); out_put: trace_event_put_ref(file->event_call); - goto out; + return ret; } static struct ftrace_func_command event_enable_cmd = { @@ -4079,20 +4055,17 @@ early_event_add_tracer(struct dentry *parent, struct trace_array *tr) { int ret; - mutex_lock(&event_mutex); + guard(mutex)(&event_mutex); ret = create_event_toplevel_files(parent, tr); if (ret) - goto out_unlock; + return ret; down_write(&trace_event_sem); __trace_early_add_event_dirs(tr); up_write(&trace_event_sem); - out_unlock: - mutex_unlock(&event_mutex); - - return ret; + return 0; } /* Must be called with event_mutex held */ |