evious"			\
-				     ::: "memory")
-#endif
-
 /* Prefetch support.  This is tuned for UltraSPARC-III and later.
  * UltraSPARC-I will treat these as nops, and UltraSPARC-II has
  * a shallower prefetch queue than later chips.
diff --git a/arch/sparc/include/asm/vdso/processor.h b/arch/sparc/include/asm/vdso/processor.h
new file mode 100644
index 0000000000000000000000000000000000000000..f7a9adc807f7c9a0444afa51aeb47649a9bdb079
--- /dev/null
+++ b/arch/sparc/include/asm/vdso/processor.h
@@ -0,0 +1,41 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _ASM_SPARC_VDSO_PROCESSOR_H
+#define _ASM_SPARC_VDSO_PROCESSOR_H
+
+#include <linux/compiler.h>
+
+#if defined(__arch64__)
+
+/* Please see the commentary in asm/backoff.h for a description of
+ * what these instructions are doing and how they have been chosen.
+ * To make a long story short, we are trying to yield the current cpu
+ * strand during busy loops.
+ */
+#ifdef	BUILD_VDSO
+#define	cpu_relax()	asm volatile("\n99:\n\t"			\
+				     "rd	%%ccr, %%g0\n\t"	\
+				     "rd	%%ccr, %%g0\n\t"	\
+				     "rd	%%ccr, %%g0\n\t"	\
+				     ::: "memory")
+#else /* ! BUILD_VDSO */
+#define cpu_relax()	asm volatile("\n99:\n\t"			\
+				     "rd	%%ccr, %%g0\n\t"	\
+				     "rd	%%ccr, %%g0\n\t"	\
+				     "rd	%%ccr, %%g0\n\t"	\
+				     ".section	.pause_3insn_patch,\"ax\"\n\t"\
+				     ".word	99b\n\t"		\
+				     "wr	%%g0, 128, %%asr27\n\t"	\
+				     "nop\n\t"				\
+				     "nop\n\t"				\
+				     ".previous"			\
+				     ::: "memory")
+#endif /* BUILD_VDSO */
+
+#else /* ! __arch64__ */
+
+#define cpu_relax()	barrier()
+
+#endif /* __arch64__ */
+
+#endif /* _ASM_SPARC_VDSO_PROCESSOR_H */

-- 
2.51.0[PATCH v4 30/35] sparc64: vdso: Introduce vdso/processor.hThomas Weißschuh <thomas.weissschuh@linutronix.de> undefinedAndy Lutomirski <luto@kernel.org>, Thomas Gleixner <tglx@linutronix.de>, Vincenzo Frascino <vincenzo.frascino@arm.com>, Arnd Bergmann <arnd@arndb.de>, "David S. Miller" <davem@davemloft.net>, Andreas Larsson <andreas@gaisler.com>, Nick Alcock <nick.alcock@oracle.com>, John Stultz <jstultz@google.com>, Stephen Boyd <sboyd@kernel.org>, John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>, Shuah Khan <shuah@kernel.org>, Catalin Marinas <catalin.marinas@arm.com>, Will Deacon <will@kernel.org>, Theodore Ts'o <tytso@mit.edu>, "Jason A. Donenfeld" <Jason@zx2c4.com>, Russell King <linux@armlinux.org.uk>, Madhavan Srinivasan <maddy@linux.ibm.com>, Michael Ellerman <mpe@ellerman.id.au>, Nicholas Piggin <npiggin@gmail.com>, Christophe Leroy <christophe.leroy@csgroup.eu>, Huacai Chen <chenhuacai@kernel.org>, WANG Xuerui <kernel@xen0n.name>, Thomas Bogendoerfer <tsbogend@alpha.franken.de>, Heiko Carstens <hca@linux.ibm.com>, Vasily Gorbik <gor@linux.ibm.com>, Alexander Gordeev <agordeev@linux.ibm.com>, Christian Borntraeger <borntraeger@linux.ibm.com>, Sven Schnelle <svens@linux.ibm.com>, Nagarathnam Muthusamy <nagarathnam.muthusamy@oracle.com>, Shannon Nelson <sln@onemain.com> undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined�