tracing: Change trace_boot to use synth_event interface

Have trace_boot_add_synth_event() use the synth_event interface.

Also, rename synth_event_run_cmd() to synth_event_run_command() now
that trace_boot's version is gone.

Link: http://lkml.kernel.org/r/94f1fa0e31846d0bddca916b8663404b20559e34.1580323897.git.zanussi@kernel.org

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

kernel/trace/trace_boot.c

@@ -125,38 +125,31 @@ trace_boot_add_kprobe_event(struct xbc_node *node, const char *event)
 #endif
 
 #ifdef CONFIG_HIST_TRIGGERS
-extern int synth_event_run_command(const char *command);
-
 static int __init
 trace_boot_add_synth_event(struct xbc_node *node, const char *event)
 {
+	struct dynevent_cmd cmd;
 	struct xbc_node *anode;
-	char buf[MAX_BUF_LEN], *q;
+	char buf[MAX_BUF_LEN];
 	const char *p;
-	int len, delta, ret;
+	int ret;
 
-	len = ARRAY_SIZE(buf);
-	delta = snprintf(buf, len, "%s", event);
-	if (delta >= len) {
-		pr_err("Event name is too long: %s\n", event);
-		return -E2BIG;
-	}
-	len -= delta; q = buf + delta;
+	synth_event_cmd_init(&cmd, buf, MAX_BUF_LEN);
+
+	ret = synth_event_gen_cmd_start(&cmd, event, NULL);
+	if (ret)
+		return ret;
 
 	xbc_node_for_each_array_value(node, "fields", anode, p) {
-		delta = snprintf(q, len, " %s;", p);
-		if (delta >= len) {
-			pr_err("fields string is too long: %s\n", p);
-			return -E2BIG;
-		}
-		len -= delta; q += delta;
+		ret = synth_event_add_field_str(&cmd, p);
+		if (ret)
+			return ret;
 	}
 
-	ret = synth_event_run_command(buf);
+	ret = synth_event_gen_cmd_end(&cmd);
 	if (ret < 0)
 		pr_err("Failed to add synthetic event: %s\n", buf);
 
-
 	return ret;
 }
 #else

kernel/trace/trace_events_hist.c

@@ -1755,12 +1755,7 @@ static int create_or_delete_synth_event(int argc, char **argv)
 	return ret == -ECANCELED ? -EINVAL : ret;
 }
 
-int synth_event_run_command(const char *command)
-{
-	return trace_run_command(command, create_or_delete_synth_event);
-}
-
-static int synth_event_run_cmd(struct dynevent_cmd *cmd)
+static int synth_event_run_command(struct dynevent_cmd *cmd)
 {
 	struct synth_event *se;
 	int ret;
@@ -1790,7 +1785,7 @@ static int synth_event_run_cmd(struct dynevent_cmd *cmd)
 void synth_event_cmd_init(struct dynevent_cmd *cmd, char *buf, int maxlen)
 {
 	dynevent_cmd_init(cmd, buf, maxlen, DYNEVENT_TYPE_SYNTH,
-			  synth_event_run_cmd);
+			  synth_event_run_command);
 }
 EXPORT_SYMBOL_GPL(synth_event_cmd_init);