summaryrefslogtreecommitdiff
path: root/kernel/trace/trace_events.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/trace/trace_events.c')
-rw-r--r--kernel/trace/trace_events.c207
1 files changed, 22 insertions, 185 deletions
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 29a7ebcfb426..368a4d50cc30 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -1489,12 +1489,7 @@ event_subsystem_dir(struct trace_array *tr, const char *name,
}
static int
-event_create_dir(struct dentry *parent,
- struct ftrace_event_file *file,
- const struct file_operations *id,
- const struct file_operations *enable,
- const struct file_operations *filter,
- const struct file_operations *format)
+event_create_dir(struct dentry *parent, struct ftrace_event_file *file)
{
struct ftrace_event_call *call = file->event_call;
struct trace_array *tr = file->tr;
@@ -1522,12 +1517,13 @@ event_create_dir(struct dentry *parent,
if (call->class->reg && !(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE))
trace_create_file("enable", 0644, file->dir, file,
- enable);
+ &ftrace_enable_fops);
#ifdef CONFIG_PERF_EVENTS
if (call->event.type && call->class->reg)
trace_create_file("id", 0444, file->dir,
- (void *)(long)call->event.type, id);
+ (void *)(long)call->event.type,
+ &ftrace_event_id_fops);
#endif
/*
@@ -1544,10 +1540,10 @@ event_create_dir(struct dentry *parent,
}
}
trace_create_file("filter", 0644, file->dir, call,
- filter);
+ &ftrace_event_filter_fops);
trace_create_file("format", 0444, file->dir, call,
- format);
+ &ftrace_event_format_fops);
return 0;
}
@@ -1648,12 +1644,7 @@ trace_create_new_event(struct ftrace_event_call *call,
/* Add an event to a trace directory */
static int
-__trace_add_new_event(struct ftrace_event_call *call,
- struct trace_array *tr,
- const struct file_operations *id,
- const struct file_operations *enable,
- const struct file_operations *filter,
- const struct file_operations *format)
+__trace_add_new_event(struct ftrace_event_call *call, struct trace_array *tr)
{
struct ftrace_event_file *file;
@@ -1661,7 +1652,7 @@ __trace_add_new_event(struct ftrace_event_call *call,
if (!file)
return -ENOMEM;
- return event_create_dir(tr->event_dir, file, id, enable, filter, format);
+ return event_create_dir(tr->event_dir, file);
}
/*
@@ -1683,8 +1674,7 @@ __trace_early_add_new_event(struct ftrace_event_call *call,
}
struct ftrace_module_file_ops;
-static void __add_event_to_tracers(struct ftrace_event_call *call,
- struct ftrace_module_file_ops *file_ops);
+static void __add_event_to_tracers(struct ftrace_event_call *call);
/* Add an additional event_call dynamically */
int trace_add_event_call(struct ftrace_event_call *call)
@@ -1695,7 +1685,7 @@ int trace_add_event_call(struct ftrace_event_call *call)
ret = __register_event(call, NULL);
if (ret >= 0)
- __add_event_to_tracers(call, NULL);
+ __add_event_to_tracers(call);
mutex_unlock(&event_mutex);
mutex_unlock(&trace_types_lock);
@@ -1769,100 +1759,21 @@ int trace_remove_event_call(struct ftrace_event_call *call)
#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 *
-find_ftrace_file_ops(struct ftrace_module_file_ops *file_ops, struct module *mod)
-{
- /*
- * As event_calls are added in groups by module,
- * when we find one file_ops, we don't need to search for
- * each call in that module, as the rest should be the
- * same. Only search for a new one if the last one did
- * not match.
- */
- if (file_ops && mod == file_ops->mod)
- return file_ops;
-
- list_for_each_entry(file_ops, &ftrace_module_file_list, list) {
- if (file_ops->mod == mod)
- return file_ops;
- }
- return NULL;
-}
-
-static struct ftrace_module_file_ops *
-trace_create_file_ops(struct module *mod)
-{
- struct ftrace_module_file_ops *file_ops;
-
- /*
- * This is a bit of a PITA. To allow for correct reference
- * counting, modules must "own" their file_operations.
- * To do this, we allocate the file operations that will be
- * used in the event directory.
- */
-
- file_ops = kmalloc(sizeof(*file_ops), GFP_KERNEL);
- if (!file_ops)
- return NULL;
-
- file_ops->mod = mod;
-
- file_ops->id = ftrace_event_id_fops;
- file_ops->id.owner = mod;
-
- file_ops->enable = ftrace_enable_fops;
- file_ops->enable.owner = mod;
-
- file_ops->filter = ftrace_event_filter_fops;
- file_ops->filter.owner = mod;
-
- file_ops->format = ftrace_event_format_fops;
- file_ops->format.owner = mod;
-
- list_add(&file_ops->list, &ftrace_module_file_list);
-
- return file_ops;
-}
-
static void trace_module_add_events(struct module *mod)
{
- struct ftrace_module_file_ops *file_ops = NULL;
struct ftrace_event_call **call, **start, **end;
start = mod->trace_events;
end = mod->trace_events + mod->num_trace_events;
- if (start == end)
- return;
-
- file_ops = trace_create_file_ops(mod);
- if (!file_ops)
- return;
-
for_each_event(call, start, end) {
__register_event(*call, mod);
- __add_event_to_tracers(*call, file_ops);
+ __add_event_to_tracers(*call);
}
}
static void trace_module_remove_events(struct module *mod)
{
- struct ftrace_module_file_ops *file_ops;
struct ftrace_event_call *call, *p;
bool clear_trace = false;
@@ -1874,16 +1785,6 @@ static void trace_module_remove_events(struct module *mod)
__trace_remove_event_call(call);
}
}
-
- /* Now free the file_operations */
- list_for_each_entry(file_ops, &ftrace_module_file_list, list) {
- if (file_ops->mod == mod)
- break;
- }
- if (&file_ops->list != &ftrace_module_file_list) {
- list_del(&file_ops->list);
- kfree(file_ops);
- }
up_write(&trace_event_sem);
/*
@@ -1919,67 +1820,21 @@ static int trace_module_notify(struct notifier_block *self,
return 0;
}
-static int
-__trace_add_new_mod_event(struct ftrace_event_call *call,
- struct trace_array *tr,
- struct ftrace_module_file_ops *file_ops)
-{
- return __trace_add_new_event(call, tr,
- &file_ops->id, &file_ops->enable,
- &file_ops->filter, &file_ops->format);
-}
-
-#else
-static inline struct ftrace_module_file_ops *
-find_ftrace_file_ops(struct ftrace_module_file_ops *file_ops, struct module *mod)
-{
- return NULL;
-}
-static inline int trace_module_notify(struct notifier_block *self,
- unsigned long val, void *data)
-{
- return 0;
-}
-static inline int
-__trace_add_new_mod_event(struct ftrace_event_call *call,
- struct trace_array *tr,
- struct ftrace_module_file_ops *file_ops)
-{
- return -ENODEV;
-}
+static struct notifier_block trace_module_nb = {
+ .notifier_call = trace_module_notify,
+ .priority = 0,
+};
#endif /* CONFIG_MODULES */
/* Create a new event directory structure for a trace directory. */
static void
__trace_add_event_dirs(struct trace_array *tr)
{
- struct ftrace_module_file_ops *file_ops = NULL;
struct ftrace_event_call *call;
int ret;
list_for_each_entry(call, &ftrace_events, list) {
- if (call->mod) {
- /*
- * Directories for events by modules need to
- * keep module ref counts when opened (as we don't
- * want the module to disappear when reading one
- * of these files). The file_ops keep account of
- * the module ref count.
- */
- file_ops = find_ftrace_file_ops(file_ops, call->mod);
- if (!file_ops)
- continue; /* Warn? */
- ret = __trace_add_new_mod_event(call, tr, file_ops);
- if (ret < 0)
- pr_warning("Could not create directory for event %s\n",
- call->name);
- continue;
- }
- ret = __trace_add_new_event(call, tr,
- &ftrace_event_id_fops,
- &ftrace_enable_fops,
- &ftrace_event_filter_fops,
- &ftrace_event_format_fops);
+ ret = __trace_add_new_event(call, tr);
if (ret < 0)
pr_warning("Could not create directory for event %s\n",
call->name);
@@ -2287,11 +2142,7 @@ __trace_early_add_event_dirs(struct trace_array *tr)
list_for_each_entry(file, &tr->events, list) {
- ret = event_create_dir(tr->event_dir, file,
- &ftrace_event_id_fops,
- &ftrace_enable_fops,
- &ftrace_event_filter_fops,
- &ftrace_event_format_fops);
+ ret = event_create_dir(tr->event_dir, file);
if (ret < 0)
pr_warning("Could not create directory for event %s\n",
file->event_call->name);
@@ -2332,29 +2183,14 @@ __trace_remove_event_dirs(struct trace_array *tr)
remove_event_file_dir(file);
}
-static void
-__add_event_to_tracers(struct ftrace_event_call *call,
- struct ftrace_module_file_ops *file_ops)
+static void __add_event_to_tracers(struct ftrace_event_call *call)
{
struct trace_array *tr;
- list_for_each_entry(tr, &ftrace_trace_arrays, list) {
- if (file_ops)
- __trace_add_new_mod_event(call, tr, file_ops);
- else
- __trace_add_new_event(call, tr,
- &ftrace_event_id_fops,
- &ftrace_enable_fops,
- &ftrace_event_filter_fops,
- &ftrace_event_format_fops);
- }
+ list_for_each_entry(tr, &ftrace_trace_arrays, list)
+ __trace_add_new_event(call, tr);
}
-static struct notifier_block trace_module_nb = {
- .notifier_call = trace_module_notify,
- .priority = 0,
-};
-
extern struct ftrace_event_call *__start_ftrace_events[];
extern struct ftrace_event_call *__stop_ftrace_events[];
@@ -2559,10 +2395,11 @@ static __init int event_trace_init(void)
if (ret)
return ret;
+#ifdef CONFIG_MODULES
ret = register_module_notifier(&trace_module_nb);
if (ret)
pr_warning("Failed to register trace events module notifier\n");
-
+#endif
return 0;
}
early_initcall(event_trace_memsetup);