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x86: ticket spin locks: factor out more common code 

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Jan Beulich 2008-09-05 13:26:39 +01:00 committed by Ingo Molnar
parent ef1f341328
commit 08f5fcbe6e
1 changed files with 16 additions and 26 deletions
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42
include/asm-x86/spinlock.h
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@ -54,19 +54,7 @@
* 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)
{
@ -116,19 +104,7 @@ 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)
{
@ -182,6 +158,20 @@ static __always_inline void __ticket_spin_unlock(raw_spinlock_t *lock)
}
#endif
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;
}
#define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock)
#ifdef CONFIG_PARAVIRT