tools lib traceevent: If %s is a pointer, check printk formats

If the format string of TP_printk() contains a %s, and the argument is
not a string, check if the argument is a pointer that might match the
printk_formats that were stored.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20131101215500.698924777@goodmis.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/lib/traceevent/event-parse.c

@@ -3505,6 +3505,7 @@ static void print_str_arg(struct trace_seq *s, void *data, int size,
 	struct pevent *pevent = event->pevent;
 	struct print_flag_sym *flag;
 	struct format_field *field;
+	struct printk_map *printk;
 	unsigned long long val, fval;
 	unsigned long addr;
 	char *str;
@@ -3540,7 +3541,12 @@ static void print_str_arg(struct trace_seq *s, void *data, int size,
 		if (!(field->flags & FIELD_IS_ARRAY) &&
 		    field->size == pevent->long_size) {
 			addr = *(unsigned long *)(data + field->offset);
-			trace_seq_printf(s, "%lx", addr);
+			/* Check if it matches a print format */
+			printk = find_printk(pevent, addr);
+			if (printk)
+				trace_seq_puts(s, printk->printk);
+			else
+				trace_seq_printf(s, "%lx", addr);
 			break;
 		}
 		str = malloc(len + 1);