aboutsummaryrefslogtreecommitdiffstats
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.c174
1 files changed, 130 insertions, 44 deletions
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 92be9cb1d7d4..0356cae0cf74 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -40,6 +40,14 @@ static LIST_HEAD(ftrace_generic_fields);
static LIST_HEAD(ftrace_common_fields);
static bool eventdir_initialized;
+static LIST_HEAD(module_strings);
+
+struct module_string {
+ struct list_head next;
+ struct module *module;
+ char *str;
+};
+
#define GFP_TRACE (GFP_KERNEL | __GFP_ZERO)
static struct kmem_cache *field_cachep;
@@ -168,6 +176,7 @@ static int trace_define_generic_fields(void)
__generic_field(int, CPU, FILTER_CPU);
__generic_field(int, cpu, FILTER_CPU);
+ __generic_field(int, common_cpu, FILTER_CPU);
__generic_field(char *, COMM, FILTER_COMM);
__generic_field(char *, comm, FILTER_COMM);
@@ -399,7 +408,14 @@ static void test_event_printk(struct trace_event_call *call)
a = strchr(fmt + i, '&');
if ((a && (a < r)) || test_field(r, call))
dereference_flags &= ~(1ULL << arg);
+ } else if ((r = strstr(fmt + i, "__get_dynamic_array(")) &&
+ (!c || r < c)) {
+ dereference_flags &= ~(1ULL << arg);
+ } else if ((r = strstr(fmt + i, "__get_sockaddr(")) &&
+ (!c || r < c)) {
+ dereference_flags &= ~(1ULL << arg);
}
+
next_arg:
i--;
arg++;
@@ -759,7 +775,9 @@ void trace_event_follow_fork(struct trace_array *tr, bool enable)
static void
event_filter_pid_sched_switch_probe_pre(void *data, bool preempt,
- struct task_struct *prev, struct task_struct *next)
+ struct task_struct *prev,
+ struct task_struct *next,
+ unsigned int prev_state)
{
struct trace_array *tr = data;
struct trace_pid_list *no_pid_list;
@@ -783,7 +801,9 @@ event_filter_pid_sched_switch_probe_pre(void *data, bool preempt,
static void
event_filter_pid_sched_switch_probe_post(void *data, bool preempt,
- struct task_struct *prev, struct task_struct *next)
+ struct task_struct *prev,
+ struct task_struct *next,
+ unsigned int prev_state)
{
struct trace_array *tr = data;
struct trace_pid_list *no_pid_list;
@@ -1705,9 +1725,9 @@ static LIST_HEAD(event_subsystems);
static int subsystem_open(struct inode *inode, struct file *filp)
{
+ struct trace_subsystem_dir *dir = NULL, *iter_dir;
+ struct trace_array *tr = NULL, *iter_tr;
struct event_subsystem *system = NULL;
- struct trace_subsystem_dir *dir = NULL; /* Initialize for gcc */
- struct trace_array *tr;
int ret;
if (tracing_is_disabled())
@@ -1716,10 +1736,12 @@ static int subsystem_open(struct inode *inode, struct file *filp)
/* Make sure the system still exists */
mutex_lock(&event_mutex);
mutex_lock(&trace_types_lock);
- list_for_each_entry(tr, &ftrace_trace_arrays, list) {
- list_for_each_entry(dir, &tr->systems, list) {
- if (dir == inode->i_private) {
+ list_for_each_entry(iter_tr, &ftrace_trace_arrays, list) {
+ list_for_each_entry(iter_dir, &iter_tr->systems, list) {
+ if (iter_dir == inode->i_private) {
/* Don't open systems with no events */
+ tr = iter_tr;
+ dir = iter_dir;
if (dir->nr_events) {
__get_system_dir(dir);
system = dir->subsystem;
@@ -1735,9 +1757,6 @@ static int subsystem_open(struct inode *inode, struct file *filp)
if (!system)
return -ENODEV;
- /* Some versions of gcc think dir can be uninitialized here */
- WARN_ON(!dir);
-
/* Still need to increment the ref count of the system */
if (trace_array_get(tr) < 0) {
put_system(dir);
@@ -2262,8 +2281,8 @@ static struct dentry *
event_subsystem_dir(struct trace_array *tr, const char *name,
struct trace_event_file *file, struct dentry *parent)
{
+ struct event_subsystem *system, *iter;
struct trace_subsystem_dir *dir;
- struct event_subsystem *system;
struct dentry *entry;
/* First see if we did not already create this dir */
@@ -2277,13 +2296,13 @@ event_subsystem_dir(struct trace_array *tr, const char *name,
}
/* Now see if the system itself exists. */
- list_for_each_entry(system, &event_subsystems, list) {
- if (strcmp(system->name, name) == 0)
+ system = NULL;
+ list_for_each_entry(iter, &event_subsystems, list) {
+ if (strcmp(iter->name, name) == 0) {
+ system = iter;
break;
+ }
}
- /* Reset system variable when not found */
- if (&system->list == &event_subsystems)
- system = NULL;
dir = kmalloc(sizeof(*dir), GFP_KERNEL);
if (!dir)
@@ -2633,6 +2652,76 @@ static void update_event_printk(struct trace_event_call *call,
}
}
+static void add_str_to_module(struct module *module, char *str)
+{
+ struct module_string *modstr;
+
+ modstr = kmalloc(sizeof(*modstr), GFP_KERNEL);
+
+ /*
+ * If we failed to allocate memory here, then we'll just
+ * let the str memory leak when the module is removed.
+ * If this fails to allocate, there's worse problems than
+ * a leaked string on module removal.
+ */
+ if (WARN_ON_ONCE(!modstr))
+ return;
+
+ modstr->module = module;
+ modstr->str = str;
+
+ list_add(&modstr->next, &module_strings);
+}
+
+static void update_event_fields(struct trace_event_call *call,
+ struct trace_eval_map *map)
+{
+ struct ftrace_event_field *field;
+ struct list_head *head;
+ char *ptr;
+ char *str;
+ int len = strlen(map->eval_string);
+
+ /* Dynamic events should never have field maps */
+ if (WARN_ON_ONCE(call->flags & TRACE_EVENT_FL_DYNAMIC))
+ return;
+
+ head = trace_get_fields(call);
+ list_for_each_entry(field, head, link) {
+ ptr = strchr(field->type, '[');
+ if (!ptr)
+ continue;
+ ptr++;
+
+ if (!isalpha(*ptr) && *ptr != '_')
+ continue;
+
+ if (strncmp(map->eval_string, ptr, len) != 0)
+ continue;
+
+ str = kstrdup(field->type, GFP_KERNEL);
+ if (WARN_ON_ONCE(!str))
+ return;
+ ptr = str + (ptr - field->type);
+ ptr = eval_replace(ptr, map, len);
+ /* enum/sizeof string smaller than value */
+ if (WARN_ON_ONCE(!ptr)) {
+ kfree(str);
+ continue;
+ }
+
+ /*
+ * If the event is part of a module, then we need to free the string
+ * when the module is removed. Otherwise, it will stay allocated
+ * until a reboot.
+ */
+ if (call->module)
+ add_str_to_module(call->module, str);
+
+ field->type = str;
+ }
+}
+
void trace_event_eval_update(struct trace_eval_map **map, int len)
{
struct trace_event_call *call, *p;
@@ -2668,6 +2757,7 @@ void trace_event_eval_update(struct trace_eval_map **map, int len)
first = false;
}
update_event_printk(call, map[i]);
+ update_event_fields(call, map[i]);
}
}
}
@@ -2758,6 +2848,7 @@ int trace_add_event_call(struct trace_event_call *call)
mutex_unlock(&trace_types_lock);
return ret;
}
+EXPORT_SYMBOL_GPL(trace_add_event_call);
/*
* Must be called under locking of trace_types_lock, event_mutex and
@@ -2819,6 +2910,7 @@ int trace_remove_event_call(struct trace_event_call *call)
return ret;
}
+EXPORT_SYMBOL_GPL(trace_remove_event_call);
#define for_each_event(event, start, end) \
for (event = start; \
@@ -2853,6 +2945,7 @@ static void trace_module_add_events(struct module *mod)
static void trace_module_remove_events(struct module *mod)
{
struct trace_event_call *call, *p;
+ struct module_string *modstr, *m;
down_write(&trace_event_sem);
list_for_each_entry_safe(call, p, &ftrace_events, list) {
@@ -2861,6 +2954,14 @@ static void trace_module_remove_events(struct module *mod)
if (call->module == mod)
__trace_remove_event_call(call);
}
+ /* Check for any strings allocade for this module */
+ list_for_each_entry_safe(modstr, m, &module_strings, next) {
+ if (modstr->module != mod)
+ continue;
+ list_del(&modstr->next);
+ kfree(modstr->str);
+ kfree(modstr);
+ }
up_write(&trace_event_sem);
/*
@@ -3446,12 +3547,10 @@ create_event_toplevel_files(struct dentry *parent, struct trace_array *tr)
struct dentry *d_events;
struct dentry *entry;
- entry = tracefs_create_file("set_event", TRACE_MODE_WRITE, parent,
- tr, &ftrace_set_event_fops);
- if (!entry) {
- pr_warn("Could not create tracefs 'set_event' entry\n");
+ entry = trace_create_file("set_event", TRACE_MODE_WRITE, parent,
+ tr, &ftrace_set_event_fops);
+ if (!entry)
return -ENOMEM;
- }
d_events = tracefs_create_dir("events", parent);
if (!d_events) {
@@ -3461,36 +3560,26 @@ create_event_toplevel_files(struct dentry *parent, struct trace_array *tr)
entry = trace_create_file("enable", TRACE_MODE_WRITE, d_events,
tr, &ftrace_tr_enable_fops);
- if (!entry) {
- pr_warn("Could not create tracefs 'enable' entry\n");
+ if (!entry)
return -ENOMEM;
- }
/* There are not as crucial, just warn if they are not created */
- entry = tracefs_create_file("set_event_pid", TRACE_MODE_WRITE, parent,
- tr, &ftrace_set_event_pid_fops);
- if (!entry)
- pr_warn("Could not create tracefs 'set_event_pid' entry\n");
+ trace_create_file("set_event_pid", TRACE_MODE_WRITE, parent,
+ tr, &ftrace_set_event_pid_fops);
- entry = tracefs_create_file("set_event_notrace_pid",
- TRACE_MODE_WRITE, parent, tr,
- &ftrace_set_event_notrace_pid_fops);
- if (!entry)
- pr_warn("Could not create tracefs 'set_event_notrace_pid' entry\n");
+ trace_create_file("set_event_notrace_pid",
+ TRACE_MODE_WRITE, parent, tr,
+ &ftrace_set_event_notrace_pid_fops);
/* ring buffer internal formats */
- entry = trace_create_file("header_page", TRACE_MODE_READ, d_events,
+ trace_create_file("header_page", TRACE_MODE_READ, d_events,
ring_buffer_print_page_header,
&ftrace_show_header_fops);
- if (!entry)
- pr_warn("Could not create tracefs 'header_page' entry\n");
- entry = trace_create_file("header_event", TRACE_MODE_READ, d_events,
+ trace_create_file("header_event", TRACE_MODE_READ, d_events,
ring_buffer_print_entry_header,
&ftrace_show_header_fops);
- if (!entry)
- pr_warn("Could not create tracefs 'header_event' entry\n");
tr->event_dir = d_events;
@@ -3696,17 +3785,14 @@ static __init int event_trace_init_fields(void)
__init int event_trace_init(void)
{
struct trace_array *tr;
- struct dentry *entry;
int ret;
tr = top_trace_array();
if (!tr)
return -ENODEV;
- entry = tracefs_create_file("available_events", TRACE_MODE_READ,
- NULL, tr, &ftrace_avail_fops);
- if (!entry)
- pr_warn("Could not create tracefs 'available_events' entry\n");
+ trace_create_file("available_events", TRACE_MODE_READ,
+ NULL, tr, &ftrace_avail_fops);
ret = early_event_add_tracer(NULL, tr);
if (ret)