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Diffstat (limited to 'kernel/trace/trace_events.c')
-rw-r--r--kernel/trace/trace_events.c199
1 files changed, 139 insertions, 60 deletions
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 368a4d50cc3..2de53628689 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -27,12 +27,6 @@
DEFINE_MUTEX(event_mutex);
-DEFINE_MUTEX(event_storage_mutex);
-EXPORT_SYMBOL_GPL(event_storage_mutex);
-
-char event_storage[EVENT_STORAGE_SIZE];
-EXPORT_SYMBOL_GPL(event_storage);
-
LIST_HEAD(ftrace_events);
static LIST_HEAD(ftrace_common_fields);
@@ -194,29 +188,60 @@ int trace_event_raw_init(struct ftrace_event_call *call)
}
EXPORT_SYMBOL_GPL(trace_event_raw_init);
+void *ftrace_event_buffer_reserve(struct ftrace_event_buffer *fbuffer,
+ struct ftrace_event_file *ftrace_file,
+ unsigned long len)
+{
+ struct ftrace_event_call *event_call = ftrace_file->event_call;
+
+ local_save_flags(fbuffer->flags);
+ fbuffer->pc = preempt_count();
+ fbuffer->ftrace_file = ftrace_file;
+
+ fbuffer->event =
+ trace_event_buffer_lock_reserve(&fbuffer->buffer, ftrace_file,
+ event_call->event.type, len,
+ fbuffer->flags, fbuffer->pc);
+ if (!fbuffer->event)
+ return NULL;
+
+ fbuffer->entry = ring_buffer_event_data(fbuffer->event);
+ return fbuffer->entry;
+}
+EXPORT_SYMBOL_GPL(ftrace_event_buffer_reserve);
+
+void ftrace_event_buffer_commit(struct ftrace_event_buffer *fbuffer)
+{
+ event_trigger_unlock_commit(fbuffer->ftrace_file, fbuffer->buffer,
+ fbuffer->event, fbuffer->entry,
+ fbuffer->flags, fbuffer->pc);
+}
+EXPORT_SYMBOL_GPL(ftrace_event_buffer_commit);
+
int ftrace_event_reg(struct ftrace_event_call *call,
enum trace_reg type, void *data)
{
struct ftrace_event_file *file = data;
+ WARN_ON(!(call->flags & TRACE_EVENT_FL_TRACEPOINT));
switch (type) {
case TRACE_REG_REGISTER:
- return tracepoint_probe_register(call->name,
+ return tracepoint_probe_register(call->tp,
call->class->probe,
file);
case TRACE_REG_UNREGISTER:
- tracepoint_probe_unregister(call->name,
+ tracepoint_probe_unregister(call->tp,
call->class->probe,
file);
return 0;
#ifdef CONFIG_PERF_EVENTS
case TRACE_REG_PERF_REGISTER:
- return tracepoint_probe_register(call->name,
+ return tracepoint_probe_register(call->tp,
call->class->perf_probe,
call);
case TRACE_REG_PERF_UNREGISTER:
- tracepoint_probe_unregister(call->name,
+ tracepoint_probe_unregister(call->tp,
call->class->perf_probe,
call);
return 0;
@@ -328,7 +353,7 @@ static int __ftrace_event_enable_disable(struct ftrace_event_file *file,
if (ret) {
tracing_stop_cmdline_record();
pr_info("event trace: Could not enable event "
- "%s\n", call->name);
+ "%s\n", ftrace_event_name(call));
break;
}
set_bit(FTRACE_EVENT_FL_ENABLED_BIT, &file->flags);
@@ -342,6 +367,12 @@ static int __ftrace_event_enable_disable(struct ftrace_event_file *file,
return ret;
}
+int trace_event_enable_disable(struct ftrace_event_file *file,
+ int enable, int soft_disable)
+{
+ return __ftrace_event_enable_disable(file, enable, soft_disable);
+}
+
static int ftrace_event_enable_disable(struct ftrace_event_file *file,
int enable)
{
@@ -421,11 +452,6 @@ static void remove_subsystem(struct ftrace_subsystem_dir *dir)
}
}
-static void *event_file_data(struct file *filp)
-{
- return ACCESS_ONCE(file_inode(filp)->i_private);
-}
-
static void remove_event_file_dir(struct ftrace_event_file *file)
{
struct dentry *dir = file->dir;
@@ -444,6 +470,7 @@ static void remove_event_file_dir(struct ftrace_event_file *file)
list_del(&file->list);
remove_subsystem(file->system);
+ free_event_filter(file->filter);
kmem_cache_free(file_cachep, file);
}
@@ -456,27 +483,29 @@ __ftrace_set_clr_event_nolock(struct trace_array *tr, const char *match,
{
struct ftrace_event_file *file;
struct ftrace_event_call *call;
+ const char *name;
int ret = -EINVAL;
list_for_each_entry(file, &tr->events, list) {
call = file->event_call;
+ name = ftrace_event_name(call);
- if (!call->name || !call->class || !call->class->reg)
+ if (!name || !call->class || !call->class->reg)
continue;
if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)
continue;
if (match &&
- strcmp(match, call->name) != 0 &&
+ strcmp(match, name) != 0 &&
strcmp(match, call->class->system) != 0)
continue;
if (sub && strcmp(sub, call->class->system) != 0)
continue;
- if (event && strcmp(event, call->name) != 0)
+ if (event && strcmp(event, name) != 0)
continue;
ftrace_event_enable_disable(file, set);
@@ -546,6 +575,9 @@ int trace_set_clr_event(const char *system, const char *event, int set)
{
struct trace_array *tr = top_trace_array();
+ if (!tr)
+ return -ENODEV;
+
return __ftrace_set_clr_event(tr, NULL, system, event, set);
}
EXPORT_SYMBOL_GPL(trace_set_clr_event);
@@ -674,7 +706,7 @@ static int t_show(struct seq_file *m, void *v)
if (strcmp(call->class->system, TRACE_SYSTEM) != 0)
seq_printf(m, "%s:", call->class->system);
- seq_printf(m, "%s\n", call->name);
+ seq_printf(m, "%s\n", ftrace_event_name(call));
return 0;
}
@@ -767,7 +799,7 @@ system_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
mutex_lock(&event_mutex);
list_for_each_entry(file, &tr->events, list) {
call = file->event_call;
- if (!call->name || !call->class || !call->class->reg)
+ if (!ftrace_event_name(call) || !call->class || !call->class->reg)
continue;
if (system && strcmp(call->class->system, system->name) != 0)
@@ -882,7 +914,7 @@ static int f_show(struct seq_file *m, void *v)
switch ((unsigned long)v) {
case FORMAT_HEADER:
- seq_printf(m, "name: %s\n", call->name);
+ seq_printf(m, "name: %s\n", ftrace_event_name(call));
seq_printf(m, "ID: %d\n", call->event.type);
seq_printf(m, "format:\n");
return 0;
@@ -989,7 +1021,7 @@ static ssize_t
event_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
loff_t *ppos)
{
- struct ftrace_event_call *call;
+ struct ftrace_event_file *file;
struct trace_seq *s;
int r = -ENODEV;
@@ -1004,12 +1036,12 @@ event_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
trace_seq_init(s);
mutex_lock(&event_mutex);
- call = event_file_data(filp);
- if (call)
- print_event_filter(call, s);
+ file = event_file_data(filp);
+ if (file)
+ print_event_filter(file, s);
mutex_unlock(&event_mutex);
- if (call)
+ if (file)
r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len);
kfree(s);
@@ -1021,7 +1053,7 @@ static ssize_t
event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
loff_t *ppos)
{
- struct ftrace_event_call *call;
+ struct ftrace_event_file *file;
char *buf;
int err = -ENODEV;
@@ -1039,9 +1071,9 @@ event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
buf[cnt] = '\0';
mutex_lock(&event_mutex);
- call = event_file_data(filp);
- if (call)
- err = apply_event_filter(call, buf);
+ file = event_file_data(filp);
+ if (file)
+ err = apply_event_filter(file, buf);
mutex_unlock(&event_mutex);
free_page((unsigned long) buf);
@@ -1062,6 +1094,9 @@ static int subsystem_open(struct inode *inode, struct file *filp)
struct trace_array *tr;
int ret;
+ if (tracing_is_disabled())
+ return -ENODEV;
+
/* Make sure the system still exists */
mutex_lock(&trace_types_lock);
mutex_lock(&event_mutex);
@@ -1108,6 +1143,9 @@ static int system_tr_open(struct inode *inode, struct file *filp)
struct trace_array *tr = inode->i_private;
int ret;
+ if (tracing_is_disabled())
+ return -ENODEV;
+
if (trace_array_get(tr) < 0)
return -ENODEV;
@@ -1124,11 +1162,12 @@ static int system_tr_open(struct inode *inode, struct file *filp)
if (ret < 0) {
trace_array_put(tr);
kfree(dir);
+ return ret;
}
filp->private_data = dir;
- return ret;
+ return 0;
}
static int subsystem_release(struct inode *inode, struct file *file)
@@ -1495,6 +1534,7 @@ event_create_dir(struct dentry *parent, struct ftrace_event_file *file)
struct trace_array *tr = file->tr;
struct list_head *head;
struct dentry *d_events;
+ const char *name;
int ret;
/*
@@ -1508,10 +1548,11 @@ event_create_dir(struct dentry *parent, struct ftrace_event_file *file)
} else
d_events = parent;
- file->dir = debugfs_create_dir(call->name, d_events);
+ name = ftrace_event_name(call);
+ file->dir = debugfs_create_dir(name, d_events);
if (!file->dir) {
pr_warning("Could not create debugfs '%s' directory\n",
- call->name);
+ name);
return -1;
}
@@ -1535,13 +1576,16 @@ event_create_dir(struct dentry *parent, struct ftrace_event_file *file)
ret = call->class->define_fields(call);
if (ret < 0) {
pr_warning("Could not initialize trace point"
- " events/%s\n", call->name);
+ " events/%s\n", name);
return -1;
}
}
- trace_create_file("filter", 0644, file->dir, call,
+ trace_create_file("filter", 0644, file->dir, file,
&ftrace_event_filter_fops);
+ trace_create_file("trigger", 0644, file->dir, file,
+ &event_trigger_fops);
+
trace_create_file("format", 0444, file->dir, call,
&ftrace_event_format_fops);
@@ -1577,6 +1621,7 @@ static void event_remove(struct ftrace_event_call *call)
if (file->event_call != call)
continue;
ftrace_event_enable_disable(file, 0);
+ destroy_preds(file);
/*
* The do_for_each_event_file() is
* a double loop. After finding the call for this
@@ -1595,15 +1640,17 @@ static void event_remove(struct ftrace_event_call *call)
static int event_init(struct ftrace_event_call *call)
{
int ret = 0;
+ const char *name;
- if (WARN_ON(!call->name))
+ name = ftrace_event_name(call);
+ if (WARN_ON(!name))
return -EINVAL;
if (call->class->raw_init) {
ret = call->class->raw_init(call);
if (ret < 0 && ret != -ENOSYS)
pr_warn("Could not initialize trace events/%s\n",
- call->name);
+ name);
}
return ret;
@@ -1637,6 +1684,8 @@ trace_create_new_event(struct ftrace_event_call *call,
file->event_call = call;
file->tr = tr;
atomic_set(&file->sm_ref, 0);
+ atomic_set(&file->tm_ref, 0);
+ INIT_LIST_HEAD(&file->triggers);
list_add(&file->list, &tr->events);
return file;
@@ -1700,7 +1749,7 @@ static void __trace_remove_event_call(struct ftrace_event_call *call)
{
event_remove(call);
trace_destroy_fields(call);
- destroy_preds(call);
+ destroy_call_preds(call);
}
static int probe_remove_event_call(struct ftrace_event_call *call)
@@ -1763,6 +1812,16 @@ static void trace_module_add_events(struct module *mod)
{
struct ftrace_event_call **call, **start, **end;
+ if (!mod->num_trace_events)
+ return;
+
+ /* Don't add infrastructure for mods without tracepoints */
+ if (trace_module_has_bad_taint(mod)) {
+ pr_err("%s: module has bad taint, not creating trace events\n",
+ mod->name);
+ return;
+ }
+
start = mod->trace_events;
end = mod->trace_events + mod->num_trace_events;
@@ -1837,46 +1896,48 @@ __trace_add_event_dirs(struct trace_array *tr)
ret = __trace_add_new_event(call, tr);
if (ret < 0)
pr_warning("Could not create directory for event %s\n",
- call->name);
+ ftrace_event_name(call));
}
}
-#ifdef CONFIG_DYNAMIC_FTRACE
-
-/* Avoid typos */
-#define ENABLE_EVENT_STR "enable_event"
-#define DISABLE_EVENT_STR "disable_event"
-
-struct event_probe_data {
- struct ftrace_event_file *file;
- unsigned long count;
- int ref;
- bool enable;
-};
-
-static struct ftrace_event_file *
+struct ftrace_event_file *
find_event_file(struct trace_array *tr, const char *system, const char *event)
{
struct ftrace_event_file *file;
struct ftrace_event_call *call;
+ const char *name;
list_for_each_entry(file, &tr->events, list) {
call = file->event_call;
+ name = ftrace_event_name(call);
- if (!call->name || !call->class || !call->class->reg)
+ if (!name || !call->class || !call->class->reg)
continue;
if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)
continue;
- if (strcmp(event, call->name) == 0 &&
+ if (strcmp(event, name) == 0 &&
strcmp(system, call->class->system) == 0)
return file;
}
return NULL;
}
+#ifdef CONFIG_DYNAMIC_FTRACE
+
+/* Avoid typos */
+#define ENABLE_EVENT_STR "enable_event"
+#define DISABLE_EVENT_STR "disable_event"
+
+struct event_probe_data {
+ struct ftrace_event_file *file;
+ unsigned long count;
+ int ref;
+ bool enable;
+};
+
static void
event_enable_probe(unsigned long ip, unsigned long parent_ip, void **_data)
{
@@ -1925,7 +1986,7 @@ event_enable_print(struct seq_file *m, unsigned long ip,
seq_printf(m, "%s:%s:%s",
data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR,
data->file->event_call->class->system,
- data->file->event_call->name);
+ ftrace_event_name(data->file->event_call));
if (data->count == -1)
seq_printf(m, ":unlimited\n");
@@ -2008,6 +2069,9 @@ event_enable_func(struct ftrace_hash *hash,
bool enable;
int ret;
+ if (!tr)
+ return -ENODEV;
+
/* hash funcs only work with set_ftrace_filter */
if (!enabled || !param)
return -EINVAL;
@@ -2145,7 +2209,7 @@ __trace_early_add_event_dirs(struct trace_array *tr)
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);
+ ftrace_event_name(file->event_call));
}
}
@@ -2169,7 +2233,7 @@ __trace_early_add_events(struct trace_array *tr)
ret = __trace_early_add_new_event(call, tr);
if (ret < 0)
pr_warning("Could not create early event %s\n",
- call->name);
+ ftrace_event_name(call));
}
}
@@ -2303,9 +2367,15 @@ int event_trace_del_tracer(struct trace_array *tr)
{
mutex_lock(&event_mutex);
+ /* Disable any event triggers and associated soft-disabled events */
+ clear_event_triggers(tr);
+
/* Disable any running events */
__ftrace_set_clr_event_nolock(tr, NULL, NULL, NULL, 0);
+ /* Access to events are within rcu_read_lock_sched() */
+ synchronize_sched();
+
down_write(&trace_event_sem);
__trace_remove_event_dirs(tr);
debugfs_remove_recursive(tr->event_dir);
@@ -2333,6 +2403,9 @@ static __init int event_trace_enable(void)
char *token;
int ret;
+ if (!tr)
+ return -ENODEV;
+
for_each_event(iter, __start_ftrace_events, __stop_ftrace_events) {
call = *iter;
@@ -2366,6 +2439,8 @@ static __init int event_trace_enable(void)
register_event_cmds();
+ register_trigger_cmds();
+
return 0;
}
@@ -2377,6 +2452,8 @@ static __init int event_trace_init(void)
int ret;
tr = top_trace_array();
+ if (!tr)
+ return -ENODEV;
d_tracer = tracing_init_dentry();
if (!d_tracer)
@@ -2470,6 +2547,8 @@ static __init void event_trace_self_tests(void)
int ret;
tr = top_trace_array();
+ if (!tr)
+ return;
pr_info("Running tests on trace events:\n");
@@ -2493,7 +2572,7 @@ static __init void event_trace_self_tests(void)
continue;
#endif
- pr_info("Testing event %s: ", call->name);
+ pr_info("Testing event %s: ", ftrace_event_name(call));
/*
* If an event is already enabled, someone is using