1 files changed, 37 insertions, 42 deletions

diff --git a/include/asm-x86/spinlock.h b/include/asm-x86/spinlock.h
index e39c790dbfd2..157ff7fab97a 100644
--- a/include/asm-x86/spinlock.h
+++ b/include/asm-x86/spinlock.h
@@ -1,5 +1,5 @@
-#ifndef _X86_SPINLOCK_H_
-#define _X86_SPINLOCK_H_
+#ifndef ASM_X86__SPINLOCK_H
+#define ASM_X86__SPINLOCK_H
 
 #include <asm/atomic.h>
 #include <asm/rwlock.h>
@@ -21,8 +21,10 @@
 
 #ifdef CONFIG_X86_32
 # define LOCK_PTR_REG "a"
+# define REG_PTR_MODE "k"
 #else
 # define LOCK_PTR_REG "D"
+# define REG_PTR_MODE "q"
 #endif
 
 #if defined(CONFIG_X86_32) && \
@@ -54,19 +56,7 @@
  * much between them in performance though, especially as locks are out of line.
  */
 #if (NR_CPUS < 256)
-static inline int __ticket_spin_is_locked(raw_spinlock_t *lock)
-{
-        int tmp = ACCESS_ONCE(lock->slock);
-
-        return (((tmp >> 8) & 0xff) != (tmp & 0xff));
-}
-
-static inline int __ticket_spin_is_contended(raw_spinlock_t *lock)
-{
-        int tmp = ACCESS_ONCE(lock->slock);
-
-        return (((tmp >> 8) - tmp) & 0xff) > 1;
-}
+#define TICKET_SHIFT 8
 
 static __always_inline void __ticket_spin_lock(raw_spinlock_t *lock)
 {
@@ -89,19 +79,17 @@ static __always_inline void __ticket_spin_lock(raw_spinlock_t *lock)
 
 static __always_inline int __ticket_spin_trylock(raw_spinlock_t *lock)
 {
-        int tmp;
-        short new;
+        int tmp, new;
 
-        asm volatile("movw %2,%w0\n\t"
+        asm volatile("movzwl %2, %0\n\t"
                      "cmpb %h0,%b0\n\t"
+                     "leal 0x100(%" REG_PTR_MODE "0), %1\n\t"
                      "jne 1f\n\t"
-                     "movw %w0,%w1\n\t"
-                     "incb %h1\n\t"
-                     "lock ; cmpxchgw %w1,%2\n\t"
+                     LOCK_PREFIX "cmpxchgw %w1,%2\n\t"
                      "1:"
                      "sete %b1\n\t"
                      "movzbl %b1,%0\n\t"
-                     : "=&a" (tmp), "=Q" (new), "+m" (lock->slock)
+                     : "=&a" (tmp), "=&q" (new), "+m" (lock->slock)
                      :
                      : "memory", "cc");
 
@@ -116,26 +104,14 @@ static __always_inline void __ticket_spin_unlock(raw_spinlock_t *lock)
                      : "memory", "cc");
 }
 #else
-static inline int __ticket_spin_is_locked(raw_spinlock_t *lock)
-{
-        int tmp = ACCESS_ONCE(lock->slock);
-
-        return (((tmp >> 16) & 0xffff) != (tmp & 0xffff));
-}
-
-static inline int __ticket_spin_is_contended(raw_spinlock_t *lock)
-{
-        int tmp = ACCESS_ONCE(lock->slock);
-
-        return (((tmp >> 16) - tmp) & 0xffff) > 1;
-}
+#define TICKET_SHIFT 16
 
 static __always_inline void __ticket_spin_lock(raw_spinlock_t *lock)
 {
         int inc = 0x00010000;
         int tmp;
 
-        asm volatile("lock ; xaddl %0, %1\n"
+        asm volatile(LOCK_PREFIX "xaddl %0, %1\n"
                      "movzwl %w0, %2\n\t"
                      "shrl $16, %0\n\t"
                      "1:\t"
@@ -146,7 +122,7 @@ static __always_inline void __ticket_spin_lock(raw_spinlock_t *lock)
                      /* don't need lfence here, because loads are in-order */
                      "jmp 1b\n"
                      "2:"
-                     : "+Q" (inc), "+m" (lock->slock), "=r" (tmp)
+                     : "+r" (inc), "+m" (lock->slock), "=&r" (tmp)
                      :
                      : "memory", "cc");
 }
@@ -160,13 +136,13 @@ static __always_inline int __ticket_spin_trylock(raw_spinlock_t *lock)
                      "movl %0,%1\n\t"
                      "roll $16, %0\n\t"
                      "cmpl %0,%1\n\t"
+                     "leal 0x00010000(%" REG_PTR_MODE "0), %1\n\t"
                      "jne 1f\n\t"
-                     "addl $0x00010000, %1\n\t"
-                     "lock ; cmpxchgl %1,%2\n\t"
+                     LOCK_PREFIX "cmpxchgl %1,%2\n\t"
                      "1:"
                      "sete %b1\n\t"
                      "movzbl %b1,%0\n\t"
-                     : "=&a" (tmp), "=r" (new), "+m" (lock->slock)
+                     : "=&a" (tmp), "=&q" (new), "+m" (lock->slock)
                      :
                      : "memory", "cc");
 
@@ -182,7 +158,19 @@ static __always_inline void __ticket_spin_unlock(raw_spinlock_t *lock)
 }
 #endif
 
-#define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock)
+static inline int __ticket_spin_is_locked(raw_spinlock_t *lock)
+{
+        int tmp = ACCESS_ONCE(lock->slock);
+
+        return !!(((tmp >> TICKET_SHIFT) ^ tmp) & ((1 << TICKET_SHIFT) - 1));
+}
+
+static inline int __ticket_spin_is_contended(raw_spinlock_t *lock)
+{
+        int tmp = ACCESS_ONCE(lock->slock);
+
+        return (((tmp >> TICKET_SHIFT) - tmp) & ((1 << TICKET_SHIFT) - 1)) > 1;
+}
 
 #ifdef CONFIG_PARAVIRT
 /*
@@ -272,6 +260,13 @@ static __always_inline void __raw_spin_unlock(raw_spinlock_t *lock)
 {
         __ticket_spin_unlock(lock);
 }
+
+static __always_inline void __raw_spin_lock_flags(raw_spinlock_t *lock,
+                                                  unsigned long flags)
+{
+        __raw_spin_lock(lock);
+}
+
 #endif  /* CONFIG_PARAVIRT */
 
 static inline void __raw_spin_unlock_wait(raw_spinlock_t *lock)
@@ -366,4 +361,4 @@ static inline void __raw_write_unlock(raw_rwlock_t *rw)
 #define _raw_read_relax(lock)   cpu_relax()
 #define _raw_write_relax(lock)  cpu_relax()
 
-#endif
+#endif /* ASM_X86__SPINLOCK_H */