[ltt-dev] Sparc64 support added to Userspace RCU

[Mathieu Desnoyers]

* David Miller (davem at davemloft.net) wrote:
> From: Mathieu Desnoyers <mathieu.desnoyers at polymtl.ca>
> Date: Thu, 22 Oct 2009 15:57:53 -0400
> 
> > Feedback is welcome,
> 
> __sparc_v8__ does not mean 64-bit longs or pointers as implied here:
> 
> #ifndef __SIZEOF_LONG__
> #if (defined(__sparc_v8__) || defined(__sparc_v9__))
> #define __SIZEOF_LONG__ 8
> #else
> #define __SIZEOF_LONG__ 4
> #endif
> #endif
> 
> "v8" was the last 32-bit standard of the cpu architecture.
> 
> Otherwise looks fine.
> 
> Although this port won't be very useful until it can be built in
> 32-bit mode.  As most applications on sparc64 systems are still
> 32-bit.  Like on powerpc, people only rarely build things 64-bit on
> sparc64.
> 
> You need to build with "-Wa,-Av9a" on the GCC command line for that
> case so that the assembler allows the v9 instructions emitted by your
> macros, even when building for 32-bit.
> 
> Hope this helps.

Yes ! Thanks a lot for this information. I'll push the following fix in
my tree.

Mathieu

diff --git a/README b/README
index 883b808..ca23d43 100644
--- a/README
+++ b/README
@@ -18,11 +18,14 @@ BUILDING
 		Forcing a 32-bit build with 386 backward compatibility:
 		* CFLAGS="-m32 -g -O2" ./configure --host=i386-pc-linux-gnu
 
+		Forcing a 32-bit build for Sparcv9 (typical for Sparc v9)
+		* CFLAGS="-m32 -Wa,-Av9a -g -O2" ./configure
+
 ARCHITECTURES SUPPORTED
 -----------------------
 
 Currently, x86 (i386, i486, i586, i686), x86 64-bit, PowerPC 32/64, S390, S390x
-and Sparc64 are supported. Only tested on Linux so far, but should
+and Sparcv9 32/64 are supported. Only tested on Linux so far, but should
 theoretically work on other operating systems.
 
 QUICK START GUIDE
diff --git a/urcu/uatomic_arch_sparc64.h b/urcu/uatomic_arch_sparc64.h
index 35b9ac2..28829d2 100644
--- a/urcu/uatomic_arch_sparc64.h
+++ b/urcu/uatomic_arch_sparc64.h
@@ -24,7 +24,7 @@
 #include <urcu/system.h>
 
 #ifndef __SIZEOF_LONG__
-#if (defined(__sparc_v8__) || defined(__sparc_v9__))
+#ifdef __LP64__
 #define __SIZEOF_LONG__ 8
 #else
 #define __SIZEOF_LONG__ 4

-- 
Mathieu Desnoyers
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