tracing: Remove test of NULL define_fields callback

Every event (or event class) has it's define_fields callback,
so the test is redundant.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4BFA37BC.8080707@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

2 files changed, 13 insertions, 24 deletions

diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index d3b4bdf00b39..5bad9cbbf974 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -987,23 +987,21 @@ event_create_dir(struct ftrace_event_call *call, struct dentry *d_events,
                                   id);
 #endif
 
-        if (call->class->define_fields) {
-                /*
-                 * Other events may have the same class. Only update
-                 * the fields if they are not already defined.
-                 */
-                head = trace_get_fields(call);
-                if (list_empty(head)) {
-                        ret = call->class->define_fields(call);
-                        if (ret < 0) {
-                                pr_warning("Could not initialize trace point"
-                                           " events/%s\n", call->name);
-                                return ret;
-                        }
+        /*
+         * Other events may have the same class. Only update
+         * the fields if they are not already defined.
+         */
+        head = trace_get_fields(call);
+        if (list_empty(head)) {
+                ret = call->class->define_fields(call);
+                if (ret < 0) {
+                        pr_warning("Could not initialize trace point"
+                                   " events/%s\n", call->name);
+                        return ret;
                 }
-                trace_create_file("filter", 0644, call->dir, call,
-                                  filter);
         }
+        trace_create_file("filter", 0644, call->dir, call,
+                          filter);
 
         trace_create_file("format", 0444, call->dir, call,
                           format);
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 330fefd1de1c..36d40104b17f 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -639,9 +639,6 @@ static int init_subsystem_preds(struct event_subsystem *system)
         int err;
 
         list_for_each_entry(call, &ftrace_events, list) {
-                if (!call->class || !call->class->define_fields)
-                        continue;
-
                 if (strcmp(call->class->system, system->name) != 0)
                         continue;
 
@@ -658,9 +655,6 @@ static void filter_free_subsystem_preds(struct event_subsystem *system)
         struct ftrace_event_call *call;
 
         list_for_each_entry(call, &ftrace_events, list) {
-                if (!call->class || !call->class->define_fields)
-                        continue;
-
                 if (strcmp(call->class->system, system->name) != 0)
                         continue;
 
@@ -1263,9 +1257,6 @@ static int replace_system_preds(struct event_subsystem *system,
         list_for_each_entry(call, &ftrace_events, list) {
                 struct event_filter *filter = call->filter;
 
-                if (!call->class || !call->class->define_fields)
-                        continue;
-
                 if (strcmp(call->class->system, system->name) != 0)
                         continue;