There are for 4 fields in trace_event_functions with the same type of trace_print_func. Initialize them in register_trace_event() one by one looks redundant.
Let's take advantage of union to simplify the procedure. Signed-off-by: Wei Yang <[email protected]> --- include/linux/trace_events.h | 13 +++++++++---- kernel/trace/trace_output.c | 14 +++++--------- 2 files changed, 14 insertions(+), 13 deletions(-) diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index 5c6943354049..1a421246f4a2 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -122,10 +122,15 @@ typedef enum print_line_t (*trace_print_func)(struct trace_iterator *iter, int flags, struct trace_event *event); struct trace_event_functions { - trace_print_func trace; - trace_print_func raw; - trace_print_func hex; - trace_print_func binary; + union { + struct { + trace_print_func trace; + trace_print_func raw; + trace_print_func hex; + trace_print_func binary; + }; + trace_print_func print_funcs[4]; + }; }; struct trace_event { diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index 73976de7f8cc..47bf9f042b97 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -728,7 +728,7 @@ void trace_event_read_unlock(void) int register_trace_event(struct trace_event *event) { unsigned key; - int ret = 0; + int i, ret = 0; down_write(&trace_event_sem); @@ -770,14 +770,10 @@ int register_trace_event(struct trace_event *event) goto out; } - if (event->funcs->trace == NULL) - event->funcs->trace = trace_nop_print; - if (event->funcs->raw == NULL) - event->funcs->raw = trace_nop_print; - if (event->funcs->hex == NULL) - event->funcs->hex = trace_nop_print; - if (event->funcs->binary == NULL) - event->funcs->binary = trace_nop_print; + for (i = 0; i < ARRAY_SIZE(event->funcs->print_funcs); i++) { + if (!event->funcs->print_funcs[i]) + event->funcs->print_funcs[i] = trace_nop_print; + } key = event->type & (EVENT_HASHSIZE - 1); -- 2.20.1 (Apple Git-117)
