tracing/probe: Add trace_probe init and free functions

Add common trace_probe init and cleanup function in
trace_probe.c, and use it from trace_kprobe.c and trace_uprobe.c

Link: http://lkml.kernel.org/r/155931582664.28323.5934870189034740822.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 01fc49f08b70195b64644c3a77aee041ad325b38..c43c2d419dedf3d145c834682585b0a9b71d0c41 100644 (file)
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -197,6 +197,16 @@ static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs);
 static int kretprobe_dispatcher(struct kretprobe_instance *ri,
                                struct pt_regs *regs);
 
+static void free_trace_kprobe(struct trace_kprobe *tk)
+{
+       if (tk) {
+               trace_probe_cleanup(&tk->tp);
+               kfree(tk->symbol);
+               free_percpu(tk->nhit);
+               kfree(tk);
+       }
+}
+
 /*
  * Allocate new trace_probe and initialize it (including kprobes).
  */
@@ -235,49 +245,17 @@ static struct trace_kprobe *alloc_trace_kprobe(const char *group,
 
        tk->rp.maxactive = maxactive;
 
-       if (!event || !group) {
-               ret = -EINVAL;
-               goto error;
-       }
-
-       tk->tp.call.class = &tk->tp.class;
-       tk->tp.call.name = kstrdup(event, GFP_KERNEL);
-       if (!tk->tp.call.name)
-               goto error;
-
-       tk->tp.class.system = kstrdup(group, GFP_KERNEL);
-       if (!tk->tp.class.system)
+       ret = trace_probe_init(&tk->tp, event, group);
+       if (ret < 0)
                goto error;
 
        dyn_event_init(&tk->devent, &trace_kprobe_ops);
-       INIT_LIST_HEAD(&tk->tp.files);
        return tk;
 error:
-       kfree(tk->tp.call.name);
-       kfree(tk->symbol);
-       free_percpu(tk->nhit);
-       kfree(tk);
+       free_trace_kprobe(tk);
        return ERR_PTR(ret);
 }
 
-static void free_trace_kprobe(struct trace_kprobe *tk)
-{
-       int i;
-
-       if (!tk)
-               return;
-
-       for (i = 0; i < tk->tp.nr_args; i++)
-               traceprobe_free_probe_arg(&tk->tp.args[i]);
-
-       kfree(tk->tp.call.class->system);
-       kfree(tk->tp.call.name);
-       kfree(tk->tp.call.print_fmt);
-       kfree(tk->symbol);
-       free_percpu(tk->nhit);
-       kfree(tk);
-}
-
 static struct trace_kprobe *find_trace_kprobe(const char *event,
                                              const char *group)
 {
@@ -1400,7 +1378,6 @@ static struct trace_event_functions kprobe_funcs = {
 static inline void init_trace_event_call(struct trace_kprobe *tk,
                                         struct trace_event_call *call)
 {
-       INIT_LIST_HEAD(&call->class->fields);
        if (trace_kprobe_is_return(tk)) {
                call->event.funcs = &kretprobe_funcs;
                call->class->define_fields = kretprobe_event_define_fields;

diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index b6b0593844cde765deab726d33c90a811c562b25..fe4ee2e73d9203a5f1285ff83e799aaf917d5e91 100644 (file)
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -884,3 +884,39 @@ int traceprobe_define_arg_fields(struct trace_event_call *event_call,
        }
        return 0;
 }
+
+
+void trace_probe_cleanup(struct trace_probe *tp)
+{
+       int i;
+
+       for (i = 0; i < tp->nr_args; i++)
+               traceprobe_free_probe_arg(&tp->args[i]);
+
+       kfree(tp->call.class->system);
+       kfree(tp->call.name);
+       kfree(tp->call.print_fmt);
+}
+
+int trace_probe_init(struct trace_probe *tp, const char *event,
+                    const char *group)
+{
+       if (!event || !group)
+               return -EINVAL;
+
+       tp->call.class = &tp->class;
+       tp->call.name = kstrdup(event, GFP_KERNEL);
+       if (!tp->call.name)
+               return -ENOMEM;
+
+       tp->class.system = kstrdup(group, GFP_KERNEL);
+       if (!tp->class.system) {
+               kfree(tp->call.name);
+               tp->call.name = NULL;
+               return -ENOMEM;
+       }
+       INIT_LIST_HEAD(&tp->files);
+       INIT_LIST_HEAD(&tp->class.fields);
+
+       return 0;
+}

diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 42816358dd4826ec629b0701938555a5a6ceb683..818b1d7693babea664a768ea976c4bc18da4bdd8 100644 (file)
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -248,6 +248,10 @@ static inline bool trace_probe_is_registered(struct trace_probe *tp)
        return !!(tp->flags & TP_FLAG_REGISTERED);
 }
 
+int trace_probe_init(struct trace_probe *tp, const char *event,
+                    const char *group);
+void trace_probe_cleanup(struct trace_probe *tp);
+
 /* Check the name is good for event/group/fields */
 static inline bool is_good_name(const char *name)
 {

diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 34ce671b6080143e3718c47bb426be1d7b991234..b18b7eb1a76f2d3d84773317fec3faaf8bbc9f83 100644 (file)
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -300,25 +300,17 @@ static struct trace_uprobe *
 alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret)
 {
        struct trace_uprobe *tu;
-
-       if (!event || !group)
-               return ERR_PTR(-EINVAL);
+       int ret;
 
        tu = kzalloc(SIZEOF_TRACE_UPROBE(nargs), GFP_KERNEL);
        if (!tu)
                return ERR_PTR(-ENOMEM);
 
-       tu->tp.call.class = &tu->tp.class;
-       tu->tp.call.name = kstrdup(event, GFP_KERNEL);
-       if (!tu->tp.call.name)
-               goto error;
-
-       tu->tp.class.system = kstrdup(group, GFP_KERNEL);
-       if (!tu->tp.class.system)
+       ret = trace_probe_init(&tu->tp, event, group);
+       if (ret < 0)
                goto error;
 
        dyn_event_init(&tu->devent, &trace_uprobe_ops);
-       INIT_LIST_HEAD(&tu->tp.files);
        tu->consumer.handler = uprobe_dispatcher;
        if (is_ret)
                tu->consumer.ret_handler = uretprobe_dispatcher;
@@ -326,26 +318,18 @@ alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret)
        return tu;
 
 error:
-       kfree(tu->tp.call.name);
        kfree(tu);
 
-       return ERR_PTR(-ENOMEM);
+       return ERR_PTR(ret);
 }
 
 static void free_trace_uprobe(struct trace_uprobe *tu)
 {
-       int i;
-
        if (!tu)
                return;
 
-       for (i = 0; i < tu->tp.nr_args; i++)
-               traceprobe_free_probe_arg(&tu->tp.args[i]);
-
        path_put(&tu->path);
-       kfree(tu->tp.call.class->system);
-       kfree(tu->tp.call.name);
-       kfree(tu->tp.call.print_fmt);
+       trace_probe_cleanup(&tu->tp);
        kfree(tu->filename);
        kfree(tu);
 }
@@ -1351,7 +1335,6 @@ static struct trace_event_functions uprobe_funcs = {
 static inline void init_trace_event_call(struct trace_uprobe *tu,
                                         struct trace_event_call *call)
 {
-       INIT_LIST_HEAD(&call->class->fields);
        call->event.funcs = &uprobe_funcs;
        call->class->define_fields = uprobe_event_define_fields;