[PATCH] x86: fix ticket spin lock asm constraints

Jan Beulich
2008-08-29T11:53:55Z

In addition to these changes I doubt the 'volatile' on all the ticket
lock asm()-s are really necessary.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Nick Piggin <npiggin@suse.de>

---
include/asm-x86/spinlock.h | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

--- linux-2.6.27-rc5/include/asm-x86/spinlock.h 2008-08-21 14:37:34.000000000 +0200
+++ 2.6.27-rc5-x86-spinlock-constraints/include/asm-x86/spinlock.h 2008-08-19 12:43:22.000000000 +0200
@@ -101,7 +101,7 @@ static __always_inline int __ticket_spin
"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");

@@ -146,7 +146,7 @@ static __always_inline void __ticket_spi
/* 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");
}
@@ -166,7 +166,7 @@ static __always_inline int __ticket_spin
"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");