2 files changed, 39 insertions, 5 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index be6779f963c6..0460cc0f28fd 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4918,7 +4918,7 @@ static const char readme_msg[] =
         "\t        onmax(var)               - invoke if var exceeds current max\n"
         "\t        onchange(var)            - invoke action if var changes\n\n"
         "\t    The available actions are:\n\n"
-        "\t        <synthetic_event>(param list)        - generate synthetic event\n"
+        "\t        trace(<synthetic_event>,param list)  - generate synthetic event\n"
         "\t        save(field,...)                      - save current event fields\n"
 #ifdef CONFIG_TRACER_SNAPSHOT
         "\t        snapshot()                           - snapshot the trace buffer\n"
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 2f3323ca9d24..66386ba1425f 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -419,6 +419,8 @@ struct action_data {
          */
         unsigned int            var_ref_idx;
         struct synth_event      *synth_event;
+        bool                    use_trace_keyword;
+        char                    *synth_event_name;
 
         union {
                 struct {
@@ -3700,6 +3702,8 @@ static void action_data_destroy(struct action_data *data)
         if (data->synth_event)
                 data->synth_event->ref--;
 
+        kfree(data->synth_event_name);
+
         kfree(data);
 }
 
@@ -3781,6 +3785,7 @@ static int track_data_create(struct hist_trigger_data *hist_data,
 static int parse_action_params(char *params, struct action_data *data)
 {
         char *param, *saved_param;
+        bool first_param = true;
         int ret = 0;
 
         while (params) {
@@ -3809,6 +3814,13 @@ static int parse_action_params(char *params, struct action_data *data)
                         goto out;
                 }
 
+                if (first_param && data->use_trace_keyword) {
+                        data->synth_event_name = saved_param;
+                        first_param = false;
+                        continue;
+                }
+                first_param = false;
+
                 data->params[data->n_params++] = saved_param;
         }
  out:
@@ -3886,6 +3898,9 @@ static int action_parse(char *str, struct action_data *data,
         } else {
                 char *params = strsep(&str, ")");
 
+                if (str_has_prefix(action_name, "trace"))
+                        data->use_trace_keyword = true;
+
                 if (params) {
                         ret = parse_action_params(params, data);
                         if (ret)
@@ -4088,13 +4103,19 @@ static int trace_action_create(struct hist_trigger_data *hist_data,
         unsigned int i, var_ref_idx;
         unsigned int field_pos = 0;
         struct synth_event *event;
+        char *synth_event_name;
         int ret = 0;
 
         lockdep_assert_held(&event_mutex);
 
-        event = find_synth_event(data->action_name);
+        if (data->use_trace_keyword)
+                synth_event_name = data->synth_event_name;
+        else
+                synth_event_name = data->action_name;
+
+        event = find_synth_event(synth_event_name);
         if (!event) {
-                hist_err("trace action: Couldn't find synthetic event: ", data->action_name);
+                hist_err("trace action: Couldn't find synthetic event: ", synth_event_name);
                 return -EINVAL;
         }
 
@@ -4841,8 +4862,10 @@ static void print_action_spec(struct seq_file *m,
                                 seq_puts(m, ",");
                 }
         } else if (data->action == ACTION_TRACE) {
+                if (data->use_trace_keyword)
+                        seq_printf(m, "%s", data->synth_event_name);
                 for (i = 0; i < data->n_params; i++) {
-                        if (i)
+                        if (i || data->use_trace_keyword)
                                 seq_puts(m, ",");
                         seq_printf(m, "%s", data->params[i]);
                 }
@@ -4890,6 +4913,7 @@ static bool actions_match(struct hist_trigger_data *hist_data,
         for (i = 0; i < hist_data->n_actions; i++) {
                 struct action_data *data = hist_data->actions[i];
                 struct action_data *data_test = hist_data_test->actions[i];
+                char *action_name, *action_name_test;
 
                 if (data->handler != data_test->handler)
                         return false;
@@ -4904,7 +4928,17 @@ static bool actions_match(struct hist_trigger_data *hist_data,
                                 return false;
                 }
 
-                if (strcmp(data->action_name, data_test->action_name) != 0)
+                if (data->use_trace_keyword)
+                        action_name = data->synth_event_name;
+                else
+                        action_name = data->action_name;
+
+                if (data_test->use_trace_keyword)
+                        action_name_test = data_test->synth_event_name;
+                else
+                        action_name_test = data_test->action_name;
+
+                if (strcmp(action_name, action_name_test) != 0)
                         return false;
 
                 if (data->handler == HANDLER_ONMATCH) {