Merge branch 'perf/urgent' into perf/core

[uclinux-h8/linux.git] / kernel / trace / trace_kprobe.c

diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index ae4147e..1cd3fb4 100644 (file)
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -462,6 +462,14 @@ disable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file)
                        disable_kprobe(&tk->rp.kp);
                wait = 1;
        }
+
+       /*
+        * if tk is not added to any list, it must be a local trace_kprobe
+        * created with perf_event_open. We don't need to wait for these
+        * trace_kprobes
+        */
+       if (list_empty(&tk->list))
+               wait = 0;
  out:
        if (wait) {
                /*
@@ -1358,12 +1366,9 @@ static struct trace_event_functions kprobe_funcs = {
        .trace          = print_kprobe_event
 };
 
-static int register_kprobe_event(struct trace_kprobe *tk)
+static inline void init_trace_event_call(struct trace_kprobe *tk,
+                                        struct trace_event_call *call)
 {
-       struct trace_event_call *call = &tk->tp.call;
-       int ret;
-
-       /* Initialize trace_event_call */
        INIT_LIST_HEAD(&call->class->fields);
        if (trace_kprobe_is_return(tk)) {
                call->event.funcs = &kretprobe_funcs;
@@ -1372,6 +1377,19 @@ static int register_kprobe_event(struct trace_kprobe *tk)
                call->event.funcs = &kprobe_funcs;
                call->class->define_fields = kprobe_event_define_fields;
        }
+
+       call->flags = TRACE_EVENT_FL_KPROBE;
+       call->class->reg = kprobe_register;
+       call->data = tk;
+}
+
+static int register_kprobe_event(struct trace_kprobe *tk)
+{
+       struct trace_event_call *call = &tk->tp.call;
+       int ret = 0;
+
+       init_trace_event_call(tk, call);
+
        if (set_print_fmt(&tk->tp, trace_kprobe_is_return(tk)) < 0)
                return -ENOMEM;
        ret = register_trace_event(&call->event);
@@ -1379,9 +1397,6 @@ static int register_kprobe_event(struct trace_kprobe *tk)
                kfree(call->print_fmt);
                return -ENODEV;
        }
-       call->flags = TRACE_EVENT_FL_KPROBE;
-       call->class->reg = kprobe_register;
-       call->data = tk;
        ret = trace_add_event_call(call);
        if (ret) {
                pr_info("Failed to register kprobe event: %s\n",
@@ -1403,6 +1418,66 @@ static int unregister_kprobe_event(struct trace_kprobe *tk)
        return ret;
 }
 
+#ifdef CONFIG_PERF_EVENTS
+/* create a trace_kprobe, but don't add it to global lists */
+struct trace_event_call *
+create_local_trace_kprobe(char *func, void *addr, unsigned long offs,
+                         bool is_return)
+{
+       struct trace_kprobe *tk;
+       int ret;
+       char *event;
+
+       /*
+        * local trace_kprobes are not added to probe_list, so they are never
+        * searched in find_trace_kprobe(). Therefore, there is no concern of
+        * duplicated name here.
+        */
+       event = func ? func : "DUMMY_EVENT";
+
+       tk = alloc_trace_kprobe(KPROBE_EVENT_SYSTEM, event, (void *)addr, func,
+                               offs, 0 /* maxactive */, 0 /* nargs */,
+                               is_return);
+
+       if (IS_ERR(tk)) {
+               pr_info("Failed to allocate trace_probe.(%d)\n",
+                       (int)PTR_ERR(tk));
+               return ERR_CAST(tk);
+       }
+
+       init_trace_event_call(tk, &tk->tp.call);
+
+       if (set_print_fmt(&tk->tp, trace_kprobe_is_return(tk)) < 0) {
+               ret = -ENOMEM;
+               goto error;
+       }
+
+       ret = __register_trace_kprobe(tk);
+       if (ret < 0)
+               goto error;
+
+       return &tk->tp.call;
+error:
+       free_trace_kprobe(tk);
+       return ERR_PTR(ret);
+}
+
+void destroy_local_trace_kprobe(struct trace_event_call *event_call)
+{
+       struct trace_kprobe *tk;
+
+       tk = container_of(event_call, struct trace_kprobe, tp.call);
+
+       if (trace_probe_is_enabled(&tk->tp)) {
+               WARN_ON(1);
+               return;
+       }
+
+       __unregister_trace_kprobe(tk);
+       free_trace_kprobe(tk);
+}
+#endif /* CONFIG_PERF_EVENTS */
+
 /* Make a tracefs interface for controlling probe points */
 static __init int init_kprobe_trace(void)
 {