---

yaml
---
r: 100583
b: refs/heads/master
c: ecea656
h: refs/heads/master
i:
  100581: 3ed811d
  100579: d511b98
  100575: 5686918
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 785656a41f9a9c0e843a23d1ae05d900b5158f8f
+refs/heads/master: ecea656d1d5e912d2f3d332657ea4a6d8380f891

trunk/include/linux/ftrace.h

@@ -49,6 +49,7 @@ enum {
 	FTRACE_FL_ENABLED	= (1 << 3),
 	FTRACE_FL_NOTRACE	= (1 << 4),
 	FTRACE_FL_CONVERTED	= (1 << 5),
+	FTRACE_FL_FROZEN	= (1 << 6),
 };
 
 struct dyn_ftrace {
@@ -73,15 +74,18 @@ extern void ftrace_caller(void);
 extern void ftrace_call(void);
 extern void mcount_call(void);
 
+extern int skip_trace(unsigned long ip);
+
 void ftrace_disable_daemon(void);
 void ftrace_enable_daemon(void);
 
 #else
+# define skip_trace(ip)				({ 0; })
 # define ftrace_force_update()			({ 0; })
 # define ftrace_set_filter(buf, len, reset)	do { } while (0)
 # define ftrace_disable_daemon()		do { } while (0)
 # define ftrace_enable_daemon()			do { } while (0)
-#endif
+#endif /* CONFIG_DYNAMIC_FTRACE */
 
 /* totally disable ftrace - can not re-enable after this */
 void ftrace_kill(void);

trunk/kernel/trace/ftrace.c

@@ -163,6 +163,8 @@ enum {
 };
 
 static int ftrace_filtered;
+static int tracing_on;
+static int frozen_record_count;
 
 static struct hlist_head ftrace_hash[FTRACE_HASHSIZE];
 
@@ -195,6 +197,71 @@ static int ftrace_record_suspend;
 
 static struct dyn_ftrace *ftrace_free_records;
 
+
+#ifdef CONFIG_KPROBES
+static inline void freeze_record(struct dyn_ftrace *rec)
+{
+	if (!(rec->flags & FTRACE_FL_FROZEN)) {
+		rec->flags |= FTRACE_FL_FROZEN;
+		frozen_record_count++;
+	}
+}
+
+static inline void unfreeze_record(struct dyn_ftrace *rec)
+{
+	if (rec->flags & FTRACE_FL_FROZEN) {
+		rec->flags &= ~FTRACE_FL_FROZEN;
+		frozen_record_count--;
+	}
+}
+
+static inline int record_frozen(struct dyn_ftrace *rec)
+{
+	return rec->flags & FTRACE_FL_FROZEN;
+}
+#else
+# define freeze_record(rec)			({ 0; })
+# define unfreeze_record(rec)			({ 0; })
+# define record_frozen(rec)			({ 0; })
+#endif /* CONFIG_KPROBES */
+
+int skip_trace(unsigned long ip)
+{
+	unsigned long fl;
+	struct dyn_ftrace *rec;
+	struct hlist_node *t;
+	struct hlist_head *head;
+
+	if (frozen_record_count == 0)
+		return 0;
+
+	head = &ftrace_hash[hash_long(ip, FTRACE_HASHBITS)];
+	hlist_for_each_entry_rcu(rec, t, head, node) {
+		if (rec->ip == ip) {
+			if (record_frozen(rec)) {
+				if (rec->flags & FTRACE_FL_FAILED)
+					return 1;
+
+				if (!(rec->flags & FTRACE_FL_CONVERTED))
+					return 1;
+
+				if (!tracing_on || !ftrace_enabled)
+					return 1;
+
+				if (ftrace_filtered) {
+					fl = rec->flags & (FTRACE_FL_FILTER |
+							   FTRACE_FL_NOTRACE);
+					if (!fl || (fl & FTRACE_FL_NOTRACE))
+						return 1;
+				}
+			}
+			break;
+		}
+	}
+
+	return 0;
+}
+
 static inline int
 ftrace_ip_in_hash(unsigned long ip, unsigned long key)
 {
@@ -489,8 +556,11 @@ static int __ftrace_modify_code(void *data)
 		 */
 		__ftrace_update_code(NULL);
 		ftrace_replace_code(1);
-	} else if (*command & FTRACE_DISABLE_CALLS)
+		tracing_on = 1;
+	} else if (*command & FTRACE_DISABLE_CALLS) {
 		ftrace_replace_code(0);
+		tracing_on = 0;
+	}
 
 	if (*command & FTRACE_UPDATE_TRACE_FUNC)
 		ftrace_update_ftrace_func(ftrace_trace_function);

trunk/kernel/trace/trace.c

@@ -988,6 +988,9 @@ function_trace_call(unsigned long ip, unsigned long parent_ip)
 	if (unlikely(!tracer_enabled))
 		return;
 
+	if (skip_trace(ip))
+		return;
+
 	local_irq_save(flags);
 	cpu = raw_smp_processor_id();
 	data = tr->data[cpu];