From 7f34346e27394c5ed4065ac12f247042ead111fe Mon Sep 17 00:00:00 2001
From: Rabin Vincent <rabin@rab.in>
Date: Mon, 25 Jan 2010 19:43:03 +0100
Subject: [PATCH] --- yaml --- r: 183015 b: refs/heads/master c:
 c5113b61baf7a9a8616eca83e20847e7fecdc679 h: refs/heads/master i:   183013:
 8a6e1ed6c5b1e9da2c1f31ed673a4440c17a80c5   183011:
 50c874fa55ff36edf33a9aa1eeb139b11bf2ac19   183007:
 03a2cd16a78e2a4529945c1a179deaba82d25692 v: v3

---
 [refs]                                |  2 +-
 trunk/arch/arm/include/asm/spinlock.h | 36 +++++++++++++++++----------
 2 files changed, 24 insertions(+), 14 deletions(-)

diff --git a/[refs] b/[refs]
index e11ef8c3ad8e..81af29b7a63c 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 24b44a66fa240f6fc63343623ca730d39754047e
+refs/heads/master: c5113b61baf7a9a8616eca83e20847e7fecdc679
diff --git a/trunk/arch/arm/include/asm/spinlock.h b/trunk/arch/arm/include/asm/spinlock.h
index c91c64cab922..17eb355707dd 100644
--- a/trunk/arch/arm/include/asm/spinlock.h
+++ b/trunk/arch/arm/include/asm/spinlock.h
@@ -5,6 +5,22 @@
 #error SMP not supported on pre-ARMv6 CPUs
 #endif
 
+static inline void dsb_sev(void)
+{
+#if __LINUX_ARM_ARCH__ >= 7
+	__asm__ __volatile__ (
+		"dsb\n"
+		"sev"
+	);
+#elif defined(CONFIG_CPU_32v6K)
+	__asm__ __volatile__ (
+		"mcr p15, 0, %0, c7, c10, 4\n"
+		"sev"
+		: : "r" (0)
+	);
+#endif
+}
+
 /*
  * ARMv6 Spin-locking.
  *
@@ -69,13 +85,11 @@ static inline void arch_spin_unlock(arch_spinlock_t *lock)
 
 	__asm__ __volatile__(
 "	str	%1, [%0]\n"
-#ifdef CONFIG_CPU_32v6K
-"	mcr	p15, 0, %1, c7, c10, 4\n" /* DSB */
-"	sev"
-#endif
 	:
 	: "r" (&lock->lock), "r" (0)
 	: "cc");
+
+	dsb_sev();
 }
 
 /*
@@ -132,13 +146,11 @@ static inline void arch_write_unlock(arch_rwlock_t *rw)
 
 	__asm__ __volatile__(
 	"str	%1, [%0]\n"
-#ifdef CONFIG_CPU_32v6K
-"	mcr	p15, 0, %1, c7, c10, 4\n" /* DSB */
-"	sev\n"
-#endif
 	:
 	: "r" (&rw->lock), "r" (0)
 	: "cc");
+
+	dsb_sev();
 }
 
 /* write_can_lock - would write_trylock() succeed? */
@@ -188,14 +200,12 @@ static inline void arch_read_unlock(arch_rwlock_t *rw)
 "	strex	%1, %0, [%2]\n"
 "	teq	%1, #0\n"
 "	bne	1b"
-#ifdef CONFIG_CPU_32v6K
-"\n	cmp	%0, #0\n"
-"	mcreq   p15, 0, %0, c7, c10, 4\n"
-"	seveq"
-#endif
 	: "=&r" (tmp), "=&r" (tmp2)
 	: "r" (&rw->lock)
 	: "cc");
+
+	if (tmp == 0)
+		dsb_sev();
 }
 
 static inline int arch_read_trylock(arch_rwlock_t *rw)