[PATCH] x86_64: Use int operations in spinlocks to support more than 128 CPUs spinning.

Pointed out by Eric Dumazet

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 6 insertions, 6 deletions

diff --git a/include/asm-x86_64/spinlock.h b/include/asm-x86_64/spinlock.h
index 69636831ad2f..fe484a699cc3 100644
--- a/include/asm-x86_64/spinlock.h
+++ b/include/asm-x86_64/spinlock.h
@@ -18,22 +18,22 @@
  */
 
 #define __raw_spin_is_locked(x) \
-                (*(volatile signed char *)(&(x)->slock) <= 0)
+                (*(volatile signed int *)(&(x)->slock) <= 0)
 
 #define __raw_spin_lock_string \
         "\n1:\t" \
-        "lock ; decb %0\n\t" \
+        "lock ; decl %0\n\t" \
         "js 2f\n" \
         LOCK_SECTION_START("") \
         "2:\t" \
         "rep;nop\n\t" \
-        "cmpb $0,%0\n\t" \
+        "cmpl $0,%0\n\t" \
         "jle 2b\n\t" \
         "jmp 1b\n" \
         LOCK_SECTION_END
 
 #define __raw_spin_unlock_string \
-        "movb $1,%0" \
+        "movl $1,%0" \
                 :"=m" (lock->slock) : : "memory"
 
 static inline void __raw_spin_lock(raw_spinlock_t *lock)
@@ -47,10 +47,10 @@ static inline void __raw_spin_lock(raw_spinlock_t *lock)
 
 static inline int __raw_spin_trylock(raw_spinlock_t *lock)
 {
-        char oldval;
+        int oldval;
 
         __asm__ __volatile__(
-                "xchgb %b0,%1"
+                "xchgl %0,%1"
                 :"=q" (oldval), "=m" (lock->slock)
                 :"0" (0) : "memory");