tracing: correct module boundaries for ftrace_release

When the module is about the unload we release its call records.
The ftrace_release function was given wrong values representing
the module core boundaries, thus not releasing its call records.

Plus making ftrace_release function module specific.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
LKML-Reference: <1254934835-363-3-git-send-email-jolsa@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

include/linux/ftrace.h

@@ -241,7 +241,7 @@ extern void ftrace_enable_daemon(void);
 # define ftrace_set_filter(buf, len, reset)	do { } while (0)
 # define ftrace_disable_daemon()		do { } while (0)
 # define ftrace_enable_daemon()			do { } while (0)
-static inline void ftrace_release(void *start, unsigned long size) { }
+static inline void ftrace_release_mod(struct module *mod) {}
 static inline int register_ftrace_command(struct ftrace_func_command *cmd)
 {
 	return -EINVAL;

kernel/trace/ftrace.c

@@ -2658,19 +2658,17 @@ static int ftrace_convert_nops(struct module *mod,
 }
 
 #ifdef CONFIG_MODULES
-void ftrace_release(void *start, void *end)
+void ftrace_release_mod(struct module *mod)
 {
 	struct dyn_ftrace *rec;
 	struct ftrace_page *pg;
-	unsigned long s = (unsigned long)start;
-	unsigned long e = (unsigned long)end;
 
-	if (ftrace_disabled || !start || start == end)
+	if (ftrace_disabled)
 		return;
 
 	mutex_lock(&ftrace_lock);
 	do_for_each_ftrace_rec(pg, rec) {
-		if ((rec->ip >= s) && (rec->ip < e)) {
+		if (within_module_core(rec->ip, mod)) {
 			/*
 			 * rec->ip is changed in ftrace_free_rec()
 			 * It should not between s and e if record was freed.
@@ -2702,9 +2700,7 @@ static int ftrace_module_notify(struct notifier_block *self,
 				   mod->num_ftrace_callsites);
 		break;
 	case MODULE_STATE_GOING:
-		ftrace_release(mod->ftrace_callsites,
-			       mod->ftrace_callsites +
-			       mod->num_ftrace_callsites);
+		ftrace_release_mod(mod);
 		break;
 	}