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Diffstat (limited to 'kernel/trace/trace_events.c')
-rw-r--r--kernel/trace/trace_events.c121
1 files changed, 120 insertions, 1 deletions
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 0d2e47370ee7..7da1dfeb322e 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -1704,6 +1704,125 @@ __register_event(struct ftrace_event_call *call, struct module *mod)
return 0;
}
+static char *enum_replace(char *ptr, struct trace_enum_map *map, int len)
+{
+ int rlen;
+ int elen;
+
+ /* Find the length of the enum value as a string */
+ elen = snprintf(ptr, 0, "%ld", map->enum_value);
+ /* Make sure there's enough room to replace the string with the value */
+ if (len < elen)
+ return NULL;
+
+ snprintf(ptr, elen + 1, "%ld", map->enum_value);
+
+ /* Get the rest of the string of ptr */
+ rlen = strlen(ptr + len);
+ memmove(ptr + elen, ptr + len, rlen);
+ /* Make sure we end the new string */
+ ptr[elen + rlen] = 0;
+
+ return ptr + elen;
+}
+
+static void update_event_printk(struct ftrace_event_call *call,
+ struct trace_enum_map *map)
+{
+ char *ptr;
+ int quote = 0;
+ int len = strlen(map->enum_string);
+
+ for (ptr = call->print_fmt; *ptr; ptr++) {
+ if (*ptr == '\\') {
+ ptr++;
+ /* paranoid */
+ if (!*ptr)
+ break;
+ continue;
+ }
+ if (*ptr == '"') {
+ quote ^= 1;
+ continue;
+ }
+ if (quote)
+ continue;
+ if (isdigit(*ptr)) {
+ /* skip numbers */
+ do {
+ ptr++;
+ /* Check for alpha chars like ULL */
+ } while (isalnum(*ptr));
+ /*
+ * A number must have some kind of delimiter after
+ * it, and we can ignore that too.
+ */
+ continue;
+ }
+ if (isalpha(*ptr) || *ptr == '_') {
+ if (strncmp(map->enum_string, ptr, len) == 0 &&
+ !isalnum(ptr[len]) && ptr[len] != '_') {
+ ptr = enum_replace(ptr, map, len);
+ /* Hmm, enum string smaller than value */
+ if (WARN_ON_ONCE(!ptr))
+ return;
+ /*
+ * No need to decrement here, as enum_replace()
+ * returns the pointer to the character passed
+ * the enum, and two enums can not be placed
+ * back to back without something in between.
+ * We can skip that something in between.
+ */
+ continue;
+ }
+ skip_more:
+ do {
+ ptr++;
+ } while (isalnum(*ptr) || *ptr == '_');
+ /*
+ * If what comes after this variable is a '.' or
+ * '->' then we can continue to ignore that string.
+ */
+ if (*ptr == '.' || (ptr[0] == '-' && ptr[1] == '>')) {
+ ptr += *ptr == '.' ? 1 : 2;
+ goto skip_more;
+ }
+ /*
+ * Once again, we can skip the delimiter that came
+ * after the string.
+ */
+ continue;
+ }
+ }
+}
+
+void trace_event_enum_update(struct trace_enum_map **map, int len)
+{
+ struct ftrace_event_call *call, *p;
+ const char *last_system = NULL;
+ int last_i;
+ int i;
+
+ down_write(&trace_event_sem);
+ list_for_each_entry_safe(call, p, &ftrace_events, list) {
+ /* events are usually grouped together with systems */
+ if (!last_system || call->class->system != last_system) {
+ last_i = 0;
+ last_system = call->class->system;
+ }
+
+ for (i = last_i; i < len; i++) {
+ if (call->class->system == map[i]->system) {
+ /* Save the first system if need be */
+ if (!last_i)
+ last_i = i;
+ update_event_printk(call, map[i]);
+ }
+ }
+ }
+ up_write(&trace_event_sem);
+}
+
static struct ftrace_event_file *
trace_create_new_event(struct ftrace_event_call *call,
struct trace_array *tr)
@@ -1915,7 +2034,7 @@ static int trace_module_notify(struct notifier_block *self,
static struct notifier_block trace_module_nb = {
.notifier_call = trace_module_notify,
- .priority = 0,
+ .priority = 1, /* higher than trace.c module notify */
};
#endif /* CONFIG_MODULES */