tracing: Cleanup saved_cmdlines_size changes

The recent addition of saved_cmdlines_size file had some remaining
(minor - mostly coding style) issues.  Fix them by passing pointer
name to sizeof() and using scnprintf().

Link: http://lkml.kernel.org/p/1402384295-23680-1-git-send-email-namhyung@kernel.org

Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 56422f1..2b458c6 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1338,7 +1338,7 @@
 {
 	int ret;
 
-	savedcmd = kmalloc(sizeof(struct saved_cmdlines_buffer), GFP_KERNEL);
+	savedcmd = kmalloc(sizeof(*savedcmd), GFP_KERNEL);
 	if (!savedcmd)
 		return -ENOMEM;
 
@@ -3840,7 +3840,7 @@
 	int r;
 
 	arch_spin_lock(&trace_cmdline_lock);
-	r = sprintf(buf, "%u\n", savedcmd->cmdline_num);
+	r = scnprintf(buf, sizeof(buf), "%u\n", savedcmd->cmdline_num);
 	arch_spin_unlock(&trace_cmdline_lock);
 
 	return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
@@ -3857,7 +3857,7 @@
 {
 	struct saved_cmdlines_buffer *s, *savedcmd_temp;
 
-	s = kmalloc(sizeof(struct saved_cmdlines_buffer), GFP_KERNEL);
+	s = kmalloc(sizeof(*s), GFP_KERNEL);
 	if (!s)
 		return -ENOMEM;