---

yaml
---
r: 141011
b: refs/heads/master
c: cfb180f
h: refs/heads/master
i:
  141009: f4b3e20
  141007: 729f942
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 7ce7e4249921d5073e764f7ff7ad83cfa9894bd7
+refs/heads/master: cfb180f3e71b2a280a254c8646a9ab1beab63f84

trunk/kernel/trace/trace.h

@@ -804,6 +804,18 @@ struct ftrace_event_call {
 #endif
 };
 
+struct event_subsystem {
+	struct list_head	list;
+	const char		*name;
+	struct dentry		*entry;
+	struct filter_pred	**preds;
+};
+
+#define events_for_each(event)						\
+	for (event = __start_ftrace_events;				\
+	     (unsigned long)event < (unsigned long)__stop_ftrace_events; \
+	     event++)
+
 #define MAX_FILTER_PRED 8
 
 struct filter_pred;
@@ -832,6 +844,9 @@ extern int filter_add_pred(struct ftrace_event_call *call,
 			   struct filter_pred *pred);
 extern void filter_free_preds(struct ftrace_event_call *call);
 extern int filter_match_preds(struct ftrace_event_call *call, void *rec);
+extern void filter_free_subsystem_preds(struct event_subsystem *system);
+extern int filter_add_subsystem_pred(struct event_subsystem *system,
+				     struct filter_pred *pred);
 
 void event_trace_printk(unsigned long ip, const char *fmt, ...);
 extern struct ftrace_event_call __start_ftrace_events[];

trunk/kernel/trace/trace_events.c

@@ -524,6 +524,71 @@ event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
 	return cnt;
 }
 
+static ssize_t
+subsystem_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
+		      loff_t *ppos)
+{
+	struct event_subsystem *system = filp->private_data;
+	struct trace_seq *s;
+	int r;
+
+	if (*ppos)
+		return 0;
+
+	s = kmalloc(sizeof(*s), GFP_KERNEL);
+	if (!s)
+		return -ENOMEM;
+
+	trace_seq_init(s);
+
+	r = filter_print_preds(system->preds, s->buffer);
+	r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, r);
+
+	kfree(s);
+
+	return r;
+}
+
+static ssize_t
+subsystem_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
+		       loff_t *ppos)
+{
+	struct event_subsystem *system = filp->private_data;
+	char buf[64], *pbuf = buf;
+	struct filter_pred *pred;
+	int err;
+
+	if (cnt >= sizeof(buf))
+		return -EINVAL;
+
+	if (copy_from_user(&buf, ubuf, cnt))
+		return -EFAULT;
+
+	pred = kzalloc(sizeof(*pred), GFP_KERNEL);
+	if (!pred)
+		return -ENOMEM;
+
+	err = filter_parse(&pbuf, pred);
+	if (err < 0) {
+		filter_free_pred(pred);
+		return err;
+	}
+
+	if (pred->clear) {
+		filter_free_subsystem_preds(system);
+		return cnt;
+	}
+
+	if (filter_add_subsystem_pred(system, pred)) {
+		filter_free_pred(pred);
+		return -EINVAL;
+	}
+
+	*ppos += cnt;
+
+	return cnt;
+}
+
 static const struct seq_operations show_event_seq_ops = {
 	.start = t_start,
 	.next = t_next,
@@ -575,6 +640,12 @@ static const struct file_operations ftrace_event_filter_fops = {
 	.write = event_filter_write,
 };
 
+static const struct file_operations ftrace_subsystem_filter_fops = {
+	.open = tracing_open_generic,
+	.read = subsystem_filter_read,
+	.write = subsystem_filter_write,
+};
+
 static struct dentry *event_trace_events_dir(void)
 {
 	static struct dentry *d_tracer;
@@ -595,18 +666,13 @@ static struct dentry *event_trace_events_dir(void)
 	return d_events;
 }
 
-struct event_subsystem {
-	struct list_head	list;
-	const char		*name;
-	struct dentry		*entry;
-};
-
 static LIST_HEAD(event_subsystems);
 
 static struct dentry *
 event_subsystem_dir(const char *name, struct dentry *d_events)
 {
 	struct event_subsystem *system;
+	struct dentry *entry;
 
 	/* First see if we did not already create this dir */
 	list_for_each_entry(system, &event_subsystems, list) {
@@ -633,6 +699,14 @@ event_subsystem_dir(const char *name, struct dentry *d_events)
 	system->name = name;
 	list_add(&system->list, &event_subsystems);
 
+	system->preds = NULL;
+
+	entry = debugfs_create_file("filter", 0444, system->entry, system,
+				    &ftrace_subsystem_filter_fops);
+	if (!entry)
+		pr_warning("Could not create debugfs "
+			   "'%s/filter' entry\n", name);
+
 	return system->entry;
 }
 

trunk/kernel/trace/trace_events_filter.c

@@ -181,6 +181,27 @@ void filter_free_preds(struct ftrace_event_call *call)
 	}
 }
 
+void filter_free_subsystem_preds(struct event_subsystem *system)
+{
+	struct ftrace_event_call *call = __start_ftrace_events;
+	int i;
+
+	if (system->preds) {
+		for (i = 0; i < MAX_FILTER_PRED; i++)
+			filter_free_pred(system->preds[i]);
+		kfree(system->preds);
+		system->preds = NULL;
+	}
+
+	events_for_each(call) {
+		if (!call->name || !call->regfunc)
+			continue;
+
+		if (!strcmp(call->system, system->name))
+			filter_free_preds(call);
+	}
+}
+
 static int __filter_add_pred(struct ftrace_event_call *call,
 			     struct filter_pred *pred)
 {
@@ -250,6 +271,65 @@ int filter_add_pred(struct ftrace_event_call *call, struct filter_pred *pred)
 	return __filter_add_pred(call, pred);
 }
 
+static struct filter_pred *copy_pred(struct filter_pred *pred)
+{
+	struct filter_pred *new_pred = kmalloc(sizeof(*pred), GFP_KERNEL);
+	if (!new_pred)
+		return NULL;
+
+	memcpy(new_pred, pred, sizeof(*pred));
+	if (pred->str_val) {
+		new_pred->str_val = kstrdup(pred->str_val, GFP_KERNEL);
+		new_pred->field_name = kstrdup(pred->field_name, GFP_KERNEL);
+		if (!new_pred->str_val) {
+			kfree(new_pred);
+			return NULL;
+		}
+	}
+
+	return new_pred;
+}
+
+int filter_add_subsystem_pred(struct event_subsystem *system,
+			      struct filter_pred *pred)
+{
+	struct ftrace_event_call *call = __start_ftrace_events;
+	struct filter_pred *event_pred;
+	int i;
+
+	if (system->preds && !pred->compound)
+		filter_free_subsystem_preds(system);
+
+	if (!system->preds) {
+		system->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred),
+					GFP_KERNEL);
+		if (!system->preds)
+			return -ENOMEM;
+	}
+
+	for (i = 0; i < MAX_FILTER_PRED; i++) {
+		if (!system->preds[i]) {
+			system->preds[i] = pred;
+			break;
+		}
+		if (i == MAX_FILTER_PRED - 1)
+			return -EINVAL;
+	}
+
+	events_for_each(call) {
+		if (!call->name || !call->regfunc)
+			continue;
+
+		if (!strcmp(call->system, system->name)) {
+			event_pred = copy_pred(pred);
+			if (event_pred)
+				filter_add_pred(call, event_pred);
+		}
+	}
+
+	return 0;
+}
+
 int filter_parse(char **pbuf, struct filter_pred *pred)
 {
 	char *tmp, *tok, *val_str = NULL;