X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=kernel%2Ftrace%2Ftrace_events.c;h=c697c70433494d6e41e51656a767c9f575cdccba;hb=a0de055cf61338549b13079a5677ef2e1b6472ef;hp=8c91b7c8f04731e488bb1131538d378176c8d1bf;hpb=f3f3f0092477d0165f3f1bf0fd518550b2abd097;p=safe%2Fjmp%2Flinux-2.6

diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 8c91b7c..c697c70 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -15,6 +15,7 @@
 #include <linux/uaccess.h>
 #include <linux/module.h>
 #include <linux/ctype.h>
+#include <linux/slab.h>
 #include <linux/delay.h>
 
 #include <asm/setup.h>
@@ -60,10 +61,8 @@ int trace_define_field(struct ftrace_event_call *call, const char *type,
 	return 0;
 
 err:
-	if (field) {
+	if (field)
 		kfree(field->name);
-		kfree(field->type);
-	}
 	kfree(field);
 
 	return -ENOMEM;
@@ -78,7 +77,7 @@ EXPORT_SYMBOL_GPL(trace_define_field);
 	if (ret)							\
 		return ret;
 
-int trace_define_common_fields(struct ftrace_event_call *call)
+static int trace_define_common_fields(struct ftrace_event_call *call)
 {
 	int ret;
 	struct trace_entry ent;
@@ -91,11 +90,8 @@ int trace_define_common_fields(struct ftrace_event_call *call)
 
 	return ret;
 }
-EXPORT_SYMBOL_GPL(trace_define_common_fields);
 
-#ifdef CONFIG_MODULES
-
-static void trace_destroy_fields(struct ftrace_event_call *call)
+void trace_destroy_fields(struct ftrace_event_call *call)
 {
 	struct ftrace_event_field *field, *next;
 
@@ -107,27 +103,49 @@ static void trace_destroy_fields(struct ftrace_event_call *call)
 	}
 }
 
-#endif /* CONFIG_MODULES */
+int trace_event_raw_init(struct ftrace_event_call *call)
+{
+	int id;
+
+	id = register_ftrace_event(call->event);
+	if (!id)
+		return -ENODEV;
+	call->id = id;
+	INIT_LIST_HEAD(&call->fields);
 
-static void ftrace_event_enable_disable(struct ftrace_event_call *call,
+	return 0;
+}
+EXPORT_SYMBOL_GPL(trace_event_raw_init);
+
+static int ftrace_event_enable_disable(struct ftrace_event_call *call,
 					int enable)
 {
+	int ret = 0;
+
 	switch (enable) {
 	case 0:
 		if (call->enabled) {
 			call->enabled = 0;
 			tracing_stop_cmdline_record();
-			call->unregfunc(call->data);
+			call->unregfunc(call);
 		}
 		break;
 	case 1:
 		if (!call->enabled) {
-			call->enabled = 1;
 			tracing_start_cmdline_record();
-			call->regfunc(call->data);
+			ret = call->regfunc(call);
+			if (ret) {
+				tracing_stop_cmdline_record();
+				pr_info("event trace: Could not enable event "
+					"%s\n", call->name);
+				break;
+			}
+			call->enabled = 1;
 		}
 		break;
 	}
+
+	return ret;
 }
 
 static void ftrace_clear_events(void)
@@ -232,10 +250,9 @@ ftrace_event_write(struct file *file, const char __user *ubuf,
 		   size_t cnt, loff_t *ppos)
 {
 	struct trace_parser parser;
-	size_t read = 0;
-	ssize_t ret;
+	ssize_t read, ret;
 
-	if (!cnt || cnt < 0)
+	if (!cnt)
 		return 0;
 
 	ret = tracing_update_buffers();
@@ -247,7 +264,7 @@ ftrace_event_write(struct file *file, const char __user *ubuf,
 
 	read = trace_get_user(&parser, ubuf, cnt, ppos);
 
-	if (trace_parser_loaded((&parser))) {
+	if (read >= 0 && trace_parser_loaded((&parser))) {
 		int set = 1;
 
 		if (*parser.buffer == '!')
@@ -271,42 +288,32 @@ ftrace_event_write(struct file *file, const char __user *ubuf,
 static void *
 t_next(struct seq_file *m, void *v, loff_t *pos)
 {
-	struct list_head *list = m->private;
-	struct ftrace_event_call *call;
+	struct ftrace_event_call *call = v;
 
 	(*pos)++;
 
-	for (;;) {
-		if (list == &ftrace_events)
-			return NULL;
-
-		call = list_entry(list, struct ftrace_event_call, list);
-
+	list_for_each_entry_continue(call, &ftrace_events, list) {
 		/*
 		 * The ftrace subsystem is for showing formats only.
 		 * They can not be enabled or disabled via the event files.
 		 */
 		if (call->regfunc)
-			break;
-
-		list = list->next;
+			return call;
 	}
 
-	m->private = list->next;
-
-	return call;
+	return NULL;
 }
 
 static void *t_start(struct seq_file *m, loff_t *pos)
 {
-	struct ftrace_event_call *call = NULL;
+	struct ftrace_event_call *call;
 	loff_t l;
 
 	mutex_lock(&event_mutex);
 
-	m->private = ftrace_events.next;
+	call = list_entry(&ftrace_events, struct ftrace_event_call, list);
 	for (l = 0; l <= *pos; ) {
-		call = t_next(m, NULL, &l);
+		call = t_next(m, call, &l);
 		if (!call)
 			break;
 	}
@@ -316,37 +323,28 @@ static void *t_start(struct seq_file *m, loff_t *pos)
 static void *
 s_next(struct seq_file *m, void *v, loff_t *pos)
 {
-	struct list_head *list = m->private;
-	struct ftrace_event_call *call;
+	struct ftrace_event_call *call = v;
 
 	(*pos)++;
 
- retry:
-	if (list == &ftrace_events)
-		return NULL;
-
-	call = list_entry(list, struct ftrace_event_call, list);
-
-	if (!call->enabled) {
-		list = list->next;
-		goto retry;
+	list_for_each_entry_continue(call, &ftrace_events, list) {
+		if (call->enabled)
+			return call;
 	}
 
-	m->private = list->next;
-
-	return call;
+	return NULL;
 }
 
 static void *s_start(struct seq_file *m, loff_t *pos)
 {
-	struct ftrace_event_call *call = NULL;
+	struct ftrace_event_call *call;
 	loff_t l;
 
 	mutex_lock(&event_mutex);
 
-	m->private = ftrace_events.next;
+	call = list_entry(&ftrace_events, struct ftrace_event_call, list);
 	for (l = 0; l <= *pos; ) {
-		call = s_next(m, NULL, &l);
+		call = s_next(m, call, &l);
 		if (!call)
 			break;
 	}
@@ -426,7 +424,7 @@ event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
 	case 0:
 	case 1:
 		mutex_lock(&event_mutex);
-		ftrace_event_enable_disable(call, val);
+		ret = ftrace_event_enable_disable(call, val);
 		mutex_unlock(&event_mutex);
 		break;
 
@@ -436,7 +434,7 @@ event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
 
 	*ppos += cnt;
 
-	return cnt;
+	return ret ? ret : cnt;
 }
 
 static ssize_t
@@ -521,41 +519,16 @@ out:
 	return ret;
 }
 
-extern char *__bad_type_size(void);
-
-#undef FIELD
-#define FIELD(type, name)						\
-	sizeof(type) != sizeof(field.name) ? __bad_type_size() :	\
-	#type, "common_" #name, offsetof(typeof(field), name),		\
-		sizeof(field.name)
-
-static int trace_write_header(struct trace_seq *s)
-{
-	struct trace_entry field;
-
-	/* struct trace_entry */
-	return trace_seq_printf(s,
-				"\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
-				"\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
-				"\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
-				"\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
-				"\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
-				"\n",
-				FIELD(unsigned short, type),
-				FIELD(unsigned char, flags),
-				FIELD(unsigned char, preempt_count),
-				FIELD(int, pid),
-				FIELD(int, lock_depth));
-}
-
 static ssize_t
 event_format_read(struct file *filp, char __user *ubuf, size_t cnt,
 		  loff_t *ppos)
 {
 	struct ftrace_event_call *call = filp->private_data;
+	struct ftrace_event_field *field;
 	struct trace_seq *s;
+	int common_field_count = 5;
 	char *buf;
-	int r;
+	int r = 0;
 
 	if (*ppos)
 		return 0;
@@ -566,14 +539,48 @@ event_format_read(struct file *filp, char __user *ubuf, size_t cnt,
 
 	trace_seq_init(s);
 
-	/* If any of the first writes fail, so will the show_format. */
-
 	trace_seq_printf(s, "name: %s\n", call->name);
 	trace_seq_printf(s, "ID: %d\n", call->id);
 	trace_seq_printf(s, "format:\n");
-	trace_write_header(s);
 
-	r = call->show_format(call, s);
+	list_for_each_entry_reverse(field, &call->fields, link) {
+		/*
+		 * Smartly shows the array type(except dynamic array).
+		 * Normal:
+		 *	field:TYPE VAR
+		 * If TYPE := TYPE[LEN], it is shown:
+		 *	field:TYPE VAR[LEN]
+		 */
+		const char *array_descriptor = strchr(field->type, '[');
+
+		if (!strncmp(field->type, "__data_loc", 10))
+			array_descriptor = NULL;
+
+		if (!array_descriptor) {
+			r = trace_seq_printf(s, "\tfield:%s %s;\toffset:%u;"
+					"\tsize:%u;\tsigned:%d;\n",
+					field->type, field->name, field->offset,
+					field->size, !!field->is_signed);
+		} else {
+			r = trace_seq_printf(s, "\tfield:%.*s %s%s;\toffset:%u;"
+					"\tsize:%u;\tsigned:%d;\n",
+					(int)(array_descriptor - field->type),
+					field->type, field->name,
+					array_descriptor, field->offset,
+					field->size, !!field->is_signed);
+		}
+
+		if (--common_field_count == 0)
+			r = trace_seq_printf(s, "\n");
+
+		if (!r)
+			break;
+	}
+
+	if (r)
+		r = trace_seq_printf(s, "\nprint fmt: %s\n",
+				call->print_fmt);
+
 	if (!r) {
 		/*
 		 * ug!  The format output is bigger than a PAGE!!
@@ -932,12 +939,14 @@ event_create_dir(struct ftrace_event_call *call, struct dentry *d_events,
 		trace_create_file("enable", 0644, call->dir, call,
 				  enable);
 
-	if (call->id && call->profile_enable)
+	if (call->id && call->perf_event_enable)
 		trace_create_file("id", 0444, call->dir, call,
 		 		  id);
 
 	if (call->define_fields) {
-		ret = call->define_fields(call);
+		ret = trace_define_common_fields(call);
+		if (!ret)
+			ret = call->define_fields(call);
 		if (ret < 0) {
 			pr_warning("Could not initialize trace point"
 				   " events/%s\n", call->name);
@@ -947,37 +956,52 @@ event_create_dir(struct ftrace_event_call *call, struct dentry *d_events,
 				  filter);
 	}
 
-	/* A trace may not want to export its format */
-	if (!call->show_format)
-		return 0;
-
 	trace_create_file("format", 0444, call->dir, call,
 			  format);
 
 	return 0;
 }
 
-#define for_each_event(event, start, end)			\
-	for (event = start;					\
-	     (unsigned long)event < (unsigned long)end;		\
-	     event++)
+static int __trace_add_event_call(struct ftrace_event_call *call)
+{
+	struct dentry *d_events;
+	int ret;
 
-#ifdef CONFIG_MODULES
+	if (!call->name)
+		return -EINVAL;
 
-static LIST_HEAD(ftrace_module_file_list);
+	if (call->raw_init) {
+		ret = call->raw_init(call);
+		if (ret < 0) {
+			if (ret != -ENOSYS)
+				pr_warning("Could not initialize trace "
+				"events/%s\n", call->name);
+			return ret;
+		}
+	}
 
-/*
- * Modules must own their file_operations to keep up with
- * reference counting.
- */
-struct ftrace_module_file_ops {
-	struct list_head		list;
-	struct module			*mod;
-	struct file_operations		id;
-	struct file_operations		enable;
-	struct file_operations		format;
-	struct file_operations		filter;
-};
+	d_events = event_trace_events_dir();
+	if (!d_events)
+		return -ENOENT;
+
+	ret = event_create_dir(call, d_events, &ftrace_event_id_fops,
+				&ftrace_enable_fops, &ftrace_event_filter_fops,
+				&ftrace_event_format_fops);
+	if (!ret)
+		list_add(&call->list, &ftrace_events);
+
+	return ret;
+}
+
+/* Add an additional event_call dynamically */
+int trace_add_event_call(struct ftrace_event_call *call)
+{
+	int ret;
+	mutex_lock(&event_mutex);
+	ret = __trace_add_event_call(call);
+	mutex_unlock(&event_mutex);
+	return ret;
+}
 
 static void remove_subsystem_dir(const char *name)
 {
@@ -1005,6 +1029,53 @@ static void remove_subsystem_dir(const char *name)
 	}
 }
 
+/*
+ * Must be called under locking both of event_mutex and trace_event_mutex.
+ */
+static void __trace_remove_event_call(struct ftrace_event_call *call)
+{
+	ftrace_event_enable_disable(call, 0);
+	if (call->event)
+		__unregister_ftrace_event(call->event);
+	debugfs_remove_recursive(call->dir);
+	list_del(&call->list);
+	trace_destroy_fields(call);
+	destroy_preds(call);
+	remove_subsystem_dir(call->system);
+}
+
+/* Remove an event_call */
+void trace_remove_event_call(struct ftrace_event_call *call)
+{
+	mutex_lock(&event_mutex);
+	down_write(&trace_event_mutex);
+	__trace_remove_event_call(call);
+	up_write(&trace_event_mutex);
+	mutex_unlock(&event_mutex);
+}
+
+#define for_each_event(event, start, end)			\
+	for (event = start;					\
+	     (unsigned long)event < (unsigned long)end;		\
+	     event++)
+
+#ifdef CONFIG_MODULES
+
+static LIST_HEAD(ftrace_module_file_list);
+
+/*
+ * Modules must own their file_operations to keep up with
+ * reference counting.
+ */
+struct ftrace_module_file_ops {
+	struct list_head		list;
+	struct module			*mod;
+	struct file_operations		id;
+	struct file_operations		enable;
+	struct file_operations		format;
+	struct file_operations		filter;
+};
+
 static struct ftrace_module_file_ops *
 trace_create_file_ops(struct module *mod)
 {
@@ -1062,7 +1133,7 @@ static void trace_module_add_events(struct module *mod)
 		if (!call->name)
 			continue;
 		if (call->raw_init) {
-			ret = call->raw_init();
+			ret = call->raw_init(call);
 			if (ret < 0) {
 				if (ret != -ENOSYS)
 					pr_warning("Could not initialize trace "
@@ -1080,10 +1151,11 @@ static void trace_module_add_events(struct module *mod)
 				return;
 		}
 		call->mod = mod;
-		list_add(&call->list, &ftrace_events);
-		event_create_dir(call, d_events,
-				 &file_ops->id, &file_ops->enable,
-				 &file_ops->filter, &file_ops->format);
+		ret = event_create_dir(call, d_events,
+				       &file_ops->id, &file_ops->enable,
+				       &file_ops->filter, &file_ops->format);
+		if (!ret)
+			list_add(&call->list, &ftrace_events);
 	}
 }
 
@@ -1097,14 +1169,7 @@ static void trace_module_remove_events(struct module *mod)
 	list_for_each_entry_safe(call, p, &ftrace_events, list) {
 		if (call->mod == mod) {
 			found = true;
-			ftrace_event_enable_disable(call, 0);
-			if (call->event)
-				__unregister_ftrace_event(call->event);
-			debugfs_remove_recursive(call->dir);
-			list_del(&call->list);
-			trace_destroy_fields(call);
-			destroy_preds(call);
-			remove_subsystem_dir(call->system);
+			__trace_remove_event_call(call);
 		}
 	}
 
@@ -1222,7 +1287,7 @@ static __init int event_trace_init(void)
 		if (!call->name)
 			continue;
 		if (call->raw_init) {
-			ret = call->raw_init();
+			ret = call->raw_init(call);
 			if (ret < 0) {
 				if (ret != -ENOSYS)
 					pr_warning("Could not initialize trace "
@@ -1230,10 +1295,12 @@ static __init int event_trace_init(void)
 				continue;
 			}
 		}
-		list_add(&call->list, &ftrace_events);
-		event_create_dir(call, d_events, &ftrace_event_id_fops,
-				 &ftrace_enable_fops, &ftrace_event_filter_fops,
-				 &ftrace_event_format_fops);
+		ret = event_create_dir(call, d_events, &ftrace_event_id_fops,
+				       &ftrace_enable_fops,
+				       &ftrace_event_filter_fops,
+				       &ftrace_event_format_fops);
+		if (!ret)
+			list_add(&call->list, &ftrace_events);
 	}
 
 	while (true) {