From: Jesse Gross <jesse@nicira.com>
Date: Tue, 8 Feb 2011 01:22:58 +0000 (-0800)
Subject: datapath: Check for backported rcu_read_lock_held.
X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cf6cb3a2ab31a16b01e18e1db2d601e92f2a405e;p=openvswitch

datapath: Check for backported rcu_read_lock_held.

New versions of Xen backport this function.

Signed-off-by: Jesse Gross <jesse@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>
---

diff --git a/acinclude.m4 b/acinclude.m4
index fed950bd..6a829d59 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -168,6 +168,10 @@ AC_DEFUN([OVS_CHECK_LINUX26_COMPAT], [
   OVS_GREP_IFELSE([$KSRC26/include/linux/netdevice.h], [dev_disable_lro])
   OVS_GREP_IFELSE([$KSRC26/include/linux/netdevice.h], [dev_get_stats])
 
+  OVS_GREP_IFELSE([$KSRC26/include/linux/rcupdate.h], [rcu_read_lock_held], [],
+                  [OVS_GREP_IFELSE([$KSRC26/include/linux/rtnetlink.h],
+                                   [rcu_read_lock_held])])
+  
   # Check for the proto_data_valid member in struct sk_buff.  The [^@]
   # is necessary because some versions of this header remove the
   # member but retain the kerneldoc comment that describes it (which
diff --git a/datapath/linux-2.6/compat-2.6/include/linux/rcupdate.h b/datapath/linux-2.6/compat-2.6/include/linux/rcupdate.h
index f96299f4..99459ea7 100644
--- a/datapath/linux-2.6/compat-2.6/include/linux/rcupdate.h
+++ b/datapath/linux-2.6/compat-2.6/include/linux/rcupdate.h
@@ -11,7 +11,7 @@
 #define rcu_dereference_protected(p, c) (p)
 #endif
 
-#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,34)
+#ifndef HAVE_RCU_READ_LOCK_HELD
 static inline int rcu_read_lock_held(void)
 {
 	return 1;