scripts/gdb: add cmdline reader command

lx-cmdline Report the Linux Commandline used in the current kernel

[jan.kiszka@siemens.com: remove blank line from help output and fix pep8 warning]
Signed-off-by: Kieran Bingham <kieran.bingham@linaro.org>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/scripts/gdb/linux/proc.py b/scripts/gdb/linux/proc.py
index 8a733dd..6e6709c1 100644
--- a/scripts/gdb/linux/proc.py
+++ b/scripts/gdb/linux/proc.py
@@ -14,6 +14,19 @@
 import gdb
 
 
+class LxCmdLine(gdb.Command):
+    """ Report the Linux Commandline used in the current kernel.
+        Equivalent to cat /proc/cmdline on a running target"""
+
+    def __init__(self):
+        super(LxCmdLine, self).__init__("lx-cmdline", gdb.COMMAND_DATA)
+
+    def invoke(self, arg, from_tty):
+        gdb.write(gdb.parse_and_eval("saved_command_line").string() + "\n")
+
+LxCmdLine()
+
+
 class LxVersion(gdb.Command):
     """ Report the Linux Version of the current kernel.
         Equivalent to cat /proc/version on a running target"""