tracing: Consolidate some synth_event_trace code

The synth_event trace code contains some almost identical functions
and some small functions that are called only once - consolidate the
common code into single functions and fold in the small functions to
simplify the code overall.

Link: http://lkml.kernel.org/r/d1c8d8ad124a653b7543afe801d38c199ca5c20e.1580506712.git.zanussi@kernel.org
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 5b4e047..42058a1 100644 (file)
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -2053,24 +2053,72 @@ out:
 }
 EXPORT_SYMBOL_GPL(synth_event_trace_start);
 
-static int save_synth_val(struct synth_field *field, u64 val,
-                         struct synth_event_trace_state *trace_state)
+static int __synth_event_add_val(const char *field_name, u64 val,
+                                struct synth_event_trace_state *trace_state)
 {
-       struct synth_trace_event *entry = trace_state->entry;
+       struct synth_field *field = NULL;
+       struct synth_trace_event *entry;
+       struct synth_event *event;
+       int i, ret = 0;
+
+       if (!trace_state) {
+               ret = -EINVAL;
+               goto out;
+       }
+
+       /* can't mix add_next_synth_val() with add_synth_val() */
+       if (field_name) {
+               if (trace_state->add_next) {
+                       ret = -EINVAL;
+                       goto out;
+               }
+               trace_state->add_name = true;
+       } else {
+               if (trace_state->add_name) {
+                       ret = -EINVAL;
+                       goto out;
+               }
+               trace_state->add_next = true;
+       }
+
+       if (!trace_state->enabled)
+               goto out;
+
+       event = trace_state->event;
+       if (trace_state->add_name) {
+               for (i = 0; i < event->n_fields; i++) {
+                       field = event->fields[i];
+                       if (strcmp(field->name, field_name) == 0)
+                               break;
+               }
+               if (!field) {
+                       ret = -EINVAL;
+                       goto out;
+               }
+       } else {
+               if (trace_state->cur_field >= event->n_fields) {
+                       ret = -EINVAL;
+                       goto out;
+               }
+               field = event->fields[trace_state->cur_field++];
+       }
 
+       entry = trace_state->entry;
        if (field->is_string) {
                char *str_val = (char *)(long)val;
                char *str_field;
 
-               if (!str_val)
-                       return -EINVAL;
+               if (!str_val) {
+                       ret = -EINVAL;
+                       goto out;
+               }
 
                str_field = (char *)&entry->fields[field->offset];
                strscpy(str_field, str_val, STR_VAR_LEN_MAX);
        } else
                entry->fields[field->offset] = val;
-
-       return 0;
+ out:
+       return ret;
 }
 
 /**
@@ -2104,54 +2152,10 @@ static int save_synth_val(struct synth_field *field, u64 val,
 int synth_event_add_next_val(u64 val,
                             struct synth_event_trace_state *trace_state)
 {
-       struct synth_field *field;
-       struct synth_event *event;
-       int ret = 0;
-
-       if (!trace_state) {
-               ret = -EINVAL;
-               goto out;
-       }
-
-       /* can't mix add_next_synth_val() with add_synth_val() */
-       if (trace_state->add_name) {
-               ret = -EINVAL;
-               goto out;
-       }
-       trace_state->add_next = true;
-
-       if (!trace_state->enabled)
-               goto out;
-
-       event = trace_state->event;
-
-       if (trace_state->cur_field >= event->n_fields) {
-               ret = -EINVAL;
-               goto out;
-       }
-
-       field = event->fields[trace_state->cur_field++];
-       ret = save_synth_val(field, val, trace_state);
- out:
-       return ret;
+       return __synth_event_add_val(NULL, val, trace_state);
 }
 EXPORT_SYMBOL_GPL(synth_event_add_next_val);
 
-static struct synth_field *find_synth_field(struct synth_event *event,
-                                           const char *field_name)
-{
-       struct synth_field *field = NULL;
-       unsigned int i;
-
-       for (i = 0; i < event->n_fields; i++) {
-               field = event->fields[i];
-               if (strcmp(field->name, field_name) == 0)
-                       return field;
-       }
-
-       return NULL;
-}
-
 /**
  * synth_event_add_val - Add a named field's value to an open synth trace
  * @field_name: The name of the synthetic event field value to set
@@ -2183,38 +2187,7 @@ static struct synth_field *find_synth_field(struct synth_event *event,
 int synth_event_add_val(const char *field_name, u64 val,
                        struct synth_event_trace_state *trace_state)
 {
-       struct synth_trace_event *entry;
-       struct synth_event *event;
-       struct synth_field *field;
-       int ret = 0;
-
-       if (!trace_state) {
-               ret = -EINVAL;
-               goto out;
-       }
-
-       /* can't mix add_next_synth_val() with add_synth_val() */
-       if (trace_state->add_next) {
-               ret = -EINVAL;
-               goto out;
-       }
-       trace_state->add_name = true;
-
-       if (!trace_state->enabled)
-               goto out;
-
-       event = trace_state->event;
-       entry = trace_state->entry;
-
-       field = find_synth_field(event, field_name);
-       if (!field) {
-               ret = -EINVAL;
-               goto out;
-       }
-
-       ret = save_synth_val(field, val, trace_state);
- out:
-       return ret;
+       return __synth_event_add_val(field_name, val, trace_state);
 }
 EXPORT_SYMBOL_GPL(synth_event_add_val);