/* must be a power of 2 */
#define EVENT_HASHSIZE 128
-static DEFINE_MUTEX(trace_event_mutex);
+DECLARE_RWSEM(trace_event_mutex);
+
+DEFINE_PER_CPU(struct trace_seq, ftrace_event_seq);
+EXPORT_PER_CPU_SYMBOL(ftrace_event_seq);
+
static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
static int next_event_type = __TRACE_LAST_TYPE + 1;
{
int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
- s->buffer[len] = 0;
- seq_puts(m, s->buffer);
+ seq_write(m, s->buffer, len);
trace_seq_init(s);
}
}
EXPORT_SYMBOL_GPL(trace_seq_printf);
+/**
+ * trace_seq_vprintf - sequence printing of trace information
+ * @s: trace sequence descriptor
+ * @fmt: printf format string
+ *
+ * The tracer may use either sequence operations or its own
+ * copy to user routines. To simplify formating of a trace
+ * trace_seq_printf is used to store strings into a special
+ * buffer (@s). Then the output may be either used by
+ * the sequencer or pulled into another buffer.
+ */
+int
+trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args)
+{
+ int len = (PAGE_SIZE - 1) - s->len;
+ int ret;
+
+ if (!len)
+ return 0;
+
+ ret = vsnprintf(s->buffer + s->len, len, fmt, args);
+
+ /* If we can't write it all, don't bother writing anything */
+ if (ret >= len)
+ return 0;
+
+ s->len += ret;
+
+ return len;
+}
+EXPORT_SYMBOL_GPL(trace_seq_vprintf);
+
int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
{
int len = (PAGE_SIZE - 1) - s->len;
return 0;
}
+const char *
+ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
+ unsigned long flags,
+ const struct trace_print_flags *flag_array)
+{
+ unsigned long mask;
+ const char *str;
+ const char *ret = p->buffer + p->len;
+ int i;
+
+ for (i = 0; flag_array[i].name && flags; i++) {
+
+ mask = flag_array[i].mask;
+ if ((flags & mask) != mask)
+ continue;
+
+ str = flag_array[i].name;
+ flags &= ~mask;
+ if (p->len && delim)
+ trace_seq_puts(p, delim);
+ trace_seq_puts(p, str);
+ }
+
+ /* check for left over flags */
+ if (flags) {
+ if (p->len && delim)
+ trace_seq_puts(p, delim);
+ trace_seq_printf(p, "0x%lx", flags);
+ }
+
+ trace_seq_putc(p, 0);
+
+ return ret;
+}
+EXPORT_SYMBOL(ftrace_print_flags_seq);
+
+const char *
+ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
+ const struct trace_print_flags *symbol_array)
+{
+ int i;
+ const char *ret = p->buffer + p->len;
+
+ for (i = 0; symbol_array[i].name; i++) {
+
+ if (val != symbol_array[i].mask)
+ continue;
+
+ trace_seq_puts(p, symbol_array[i].name);
+ break;
+ }
+
+ if (!p->len)
+ trace_seq_printf(p, "0x%lx", val);
+
+ trace_seq_putc(p, 0);
+
+ return ret;
+}
+EXPORT_SYMBOL(ftrace_print_symbols_seq);
+
#ifdef CONFIG_KRETPROBES
static inline const char *kretprobed(const char *name)
{
* since individual threads might have already quit!
*/
rcu_read_lock();
- task = find_task_by_vpid(entry->ent.tgid);
+ task = find_task_by_vpid(entry->tgid);
if (task)
mm = get_task_mm(task);
rcu_read_unlock();
if (ip == ULONG_MAX || !ret)
break;
- if (i && ret)
- ret = trace_seq_puts(s, " <- ");
+ if (ret)
+ ret = trace_seq_puts(s, " => ");
if (!ip) {
if (ret)
ret = trace_seq_puts(s, "??");
+ if (ret)
+ ret = trace_seq_puts(s, "\n");
continue;
}
if (!ret)
break;
if (ret)
ret = seq_print_user_ip(s, mm, ip, sym_flags);
+ ret = trace_seq_puts(s, "\n");
}
if (mm)
* @type: the type of event to look for
*
* Returns an event of type @type otherwise NULL
+ * Called with trace_event_read_lock() held.
*/
struct trace_event *ftrace_find_event(int type)
{
key = type & (EVENT_HASHSIZE - 1);
- hlist_for_each_entry_rcu(event, n, &event_hash[key], node) {
+ hlist_for_each_entry(event, n, &event_hash[key], node) {
if (event->type == type)
return event;
}
return last + 1;
}
+void trace_event_read_lock(void)
+{
+ down_read(&trace_event_mutex);
+}
+
+void trace_event_read_unlock(void)
+{
+ up_read(&trace_event_mutex);
+}
+
/**
* register_ftrace_event - register output for an event type
* @event: the event type to register
unsigned key;
int ret = 0;
- mutex_lock(&trace_event_mutex);
+ down_write(&trace_event_mutex);
if (WARN_ON(!event))
goto out;
INIT_LIST_HEAD(&event->list);
if (!event->type) {
- struct list_head *list;
+ struct list_head *list = NULL;
if (next_event_type > FTRACE_MAX_EVENT) {
key = event->type & (EVENT_HASHSIZE - 1);
- hlist_add_head_rcu(&event->node, &event_hash[key]);
+ hlist_add_head(&event->node, &event_hash[key]);
ret = event->type;
out:
- mutex_unlock(&trace_event_mutex);
+ up_write(&trace_event_mutex);
return ret;
}
EXPORT_SYMBOL_GPL(register_ftrace_event);
+/*
+ * Used by module code with the trace_event_mutex held for write.
+ */
+int __unregister_ftrace_event(struct trace_event *event)
+{
+ hlist_del(&event->node);
+ list_del(&event->list);
+ return 0;
+}
+
/**
* unregister_ftrace_event - remove a no longer used event
* @event: the event to remove
*/
int unregister_ftrace_event(struct trace_event *event)
{
- mutex_lock(&trace_event_mutex);
- hlist_del(&event->node);
- list_del(&event->list);
- mutex_unlock(&trace_event_mutex);
+ down_write(&trace_event_mutex);
+ __unregister_ftrace_event(event);
+ up_write(&trace_event_mutex);
return 0;
}
trace_assign_type(field, iter->ent);
+ if (!trace_seq_puts(s, "<stack trace>\n"))
+ goto partial;
for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
- if (i) {
- if (!trace_seq_puts(s, " <= "))
- goto partial;
+ if (!field->caller[i] || (field->caller[i] == ULONG_MAX))
+ break;
+ if (!trace_seq_puts(s, " => "))
+ goto partial;
- if (!seq_print_ip_sym(s, field->caller[i], flags))
- goto partial;
- }
+ if (!seq_print_ip_sym(s, field->caller[i], flags))
+ goto partial;
if (!trace_seq_puts(s, "\n"))
goto partial;
}
trace_assign_type(field, iter->ent);
- if (!seq_print_userip_objs(field, s, flags))
+ if (!trace_seq_puts(s, "<user stack trace>\n"))
goto partial;
- if (!trace_seq_putc(s, '\n'))
+ if (!seq_print_userip_objs(field, s, flags))
goto partial;
return TRACE_TYPE_HANDLED;