[1/3] ARM: Use qrwlock implementation

Commit Message

Sebastian Andrzej Siewior Oct. 7, 2019, 9:44 p.m. UTC

Use the generic qrwlock implementation for rwlock. The WFE mechanism is
used as part of the spinlock implementation.

Signed-off-by: Sebastian Andrzej Siewior <[e-mail]>
---
 arch/arm/Kconfig                      |  1 +
 arch/arm/include/asm/Kbuild           |  1 +
 arch/arm/include/asm/spinlock.h       |  8 ++++++++
 arch/arm/include/asm/spinlock_types.h | 10 +++++++++-
 4 files changed, 19 insertions(+), 1 deletion(-)

Patch

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 8a50efb559f35..2f704531d883a 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -34,6 +34,7 @@  config ARM
 	select ARCH_SUPPORTS_ATOMIC_RMW
 	select ARCH_USE_BUILTIN_BSWAP
 	select ARCH_USE_CMPXCHG_LOCKREF
+	select ARCH_USE_QUEUED_RWLOCKS if !CPU_V6
 	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
 	select ARCH_WANT_IPC_PARSE_VERSION
 	select BINFMT_FLAT_ARGVP_ENVP_ON_STACK
diff --git a/arch/arm/include/asm/Kbuild b/arch/arm/include/asm/Kbuild
index 68ca86f85eb73..5327be7572cd2 100644
--- a/arch/arm/include/asm/Kbuild
+++ b/arch/arm/include/asm/Kbuild
@@ -18,6 +18,7 @@  generic-y += preempt.h
 generic-y += seccomp.h
 generic-y += serial.h
 generic-y += trace_clock.h
+generic-y += qrwlock.h
 
 generated-y += mach-types.h
 generated-y += unistd-nr.h
diff --git a/arch/arm/include/asm/spinlock.h b/arch/arm/include/asm/spinlock.h
index 8f009e788ad40..e23f71b2cd43d 100644
--- a/arch/arm/include/asm/spinlock.h
+++ b/arch/arm/include/asm/spinlock.h
@@ -128,6 +128,7 @@  static inline int arch_spin_is_contended(arch_spinlock_t *lock)
 }
 #define arch_spin_is_contended	arch_spin_is_contended
 
+#ifdef CONFIG_CPU_V6
 /*
  * RWLOCKS
  *
@@ -270,4 +271,11 @@  static inline int arch_read_trylock(arch_rwlock_t *rw)
 	}
 }
 
+#else
+
+#include <asm/qrwlock.h>
+#define smp_mb__after_spinlock()       smp_mb()
+
+#endif
+
 #endif /* __ASM_SPINLOCK_H */
diff --git a/arch/arm/include/asm/spinlock_types.h b/arch/arm/include/asm/spinlock_types.h
index 5976958647fe1..c942a75250bb2 100644
--- a/arch/arm/include/asm/spinlock_types.h
+++ b/arch/arm/include/asm/spinlock_types.h
@@ -29,6 +29,14 @@  typedef struct {
 	u32 lock;
 } arch_rwlock_t;
 
-#define __ARCH_RW_LOCK_UNLOCKED		{ 0 }
+#ifdef CONFIG_CPU_V6
+
+#define __ARCH_RW_LOCK_UNLOCKED                { 0 }
+
+#else
+
+#include <asm-generic/qrwlock_types.h>
+
+#endif
 
 #endif