diff options
| -rw-r--r-- | include/linux/ftrace_event.h | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h index 5ac97a42950..dc7fc646fa2 100644 --- a/include/linux/ftrace_event.h +++ b/include/linux/ftrace_event.h @@ -169,7 +169,14 @@ struct ftrace_event_call { * bit 1: enabled * bit 2: filter_active * - * Must hold event_mutex to change. + * Changes to flags must hold the event_mutex. + * + * Note: Reads of flags do not hold the event_mutex since + * they occur in critical sections. But the way flags + * is currently used, these changes do no affect the code + * except that when a change is made, it may have a slight + * delay in propagating the changes to other CPUs due to + * caching and such. */ unsigned int flags; |