From: Paolo Bonzini <pbonzini@redhat.com>
Date: Sat, 10 Sep 2011 19:26:19 +0000 (-0700)
Subject: cmm: let per-arch files provide cmm_smp_* barriers
X-Git-Tag: v0.6.5~29
X-Git-Url: http://git.liburcu.org/?p=userspace-rcu.git;a=commitdiff_plain;h=0bd48ad389868e7b98f14fb88f9b4a81ff93b6d0

cmm: let per-arch files provide cmm_smp_* barriers

x86 instructions lfence and sfence are rarely needed, thus we want
the cmm_smp_rmb/cmm_smp_wmb macros to be simple compiler barriers.
So, let the per-arch files override the default definitions in
arch/generic.h.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---

diff --git a/urcu/arch/generic.h b/urcu/arch/generic.h
index 100d3c6..1ea7f59 100644
--- a/urcu/arch/generic.h
+++ b/urcu/arch/generic.h
@@ -100,22 +100,50 @@ extern "C" {
 #endif
 
 #ifdef CONFIG_RCU_SMP
+#ifndef cmm_smp_mb
 #define cmm_smp_mb()	cmm_mb()
+#endif
+#ifndef cmm_smp_rmb
 #define cmm_smp_rmb()	cmm_rmb()
+#endif
+#ifndef cmm_smp_wmb
 #define cmm_smp_wmb()	cmm_wmb()
+#endif
+#ifndef cmm_smp_mc
 #define cmm_smp_mc()	cmm_mc()
+#endif
+#ifndef cmm_smp_rmc
 #define cmm_smp_rmc()	cmm_rmc()
+#endif
+#ifndef cmm_smp_wmc
 #define cmm_smp_wmc()	cmm_wmc()
+#endif
+#ifndef cmm_smp_read_barrier_depends
 #define cmm_smp_read_barrier_depends()	cmm_read_barrier_depends()
+#endif
 #else
+#ifndef cmm_smp_mb
 #define cmm_smp_mb()	cmm_barrier()
+#endif
+#ifndef cmm_smp_rmb
 #define cmm_smp_rmb()	cmm_barrier()
+#endif
+#ifndef cmm_smp_wmb
 #define cmm_smp_wmb()	cmm_barrier()
+#endif
+#ifndef cmm_smp_mc
 #define cmm_smp_mc()	cmm_barrier()
+#endif
+#ifndef cmm_smp_rmc
 #define cmm_smp_rmc()	cmm_barrier()
+#endif
+#ifndef cmm_smp_wmc
 #define cmm_smp_wmc()	cmm_barrier()
+#endif
+#ifndef cmm_smp_read_barrier_depends
 #define cmm_smp_read_barrier_depends()
 #endif
+#endif
 
 #ifndef caa_cpu_relax
 #define caa_cpu_relax()		cmm_barrier()