From eb33154d7dd2a1e2f0b43680ec7b3cb4db20da71 Mon Sep 17 00:00:00 2001
From: Marc Abramowitz <marc@marc-abramowitz.com>
Date: Wed, 29 Feb 2012 16:25:33 -0800
Subject: [PATCH] Define #DEFINE_SEMAPHORE if not defined. At some point in
 Linux kernel history, DECLARE_MUTEX was renamed to DEFINE_SEMAPHORE. Older
 kernels like the stock kernel on Ubuntu 10.04.4 (Linux ubuntu
 2.6.32-38-generic #83-Ubuntu SMP Wed Jan 4 11:13:04 UTC 2012 i686 GNU/Linux)
 don't have DEFINE_SEMAPHORE in their headers.

Fixes GH-11.
---
 driver/dtrace_linux.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/driver/dtrace_linux.h b/driver/dtrace_linux.h
index bfcfa2b..069bda5 100644
--- a/driver/dtrace_linux.h
+++ b/driver/dtrace_linux.h
@@ -65,6 +65,10 @@
 
 # define MUTEX_HELD dtrace_mutex_is_locked
 
+# if !defined(DEFINE_SEMAPHORE)
+#   define DEFINE_SEMAPHORE(_m)  DECLARE_MUTEX(_m)
+# endif
+
 #define PRIV_EFFECTIVE          (1 << 0)
 #define PRIV_DTRACE_KERNEL      (1 << 1)
 #define PRIV_DTRACE_PROC        (1 << 2)