提交 08f5fcbe 编写于 作者: J Jan Beulich 提交者: Ingo Molnar

x86: ticket spin locks: factor out more common code

Signed-off-by: NJan Beulich <jbeulich@novell.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
上级 ef1f3413
...@@ -54,19 +54,7 @@ ...@@ -54,19 +54,7 @@
* much between them in performance though, especially as locks are out of line. * much between them in performance though, especially as locks are out of line.
*/ */
#if (NR_CPUS < 256) #if (NR_CPUS < 256)
static inline int __ticket_spin_is_locked(raw_spinlock_t *lock) #define TICKET_SHIFT 8
{
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;
}
static __always_inline void __ticket_spin_lock(raw_spinlock_t *lock) 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) ...@@ -116,19 +104,7 @@ static __always_inline void __ticket_spin_unlock(raw_spinlock_t *lock)
: "memory", "cc"); : "memory", "cc");
} }
#else #else
static inline int __ticket_spin_is_locked(raw_spinlock_t *lock) #define TICKET_SHIFT 16
{
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;
}
static __always_inline void __ticket_spin_lock(raw_spinlock_t *lock) 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) ...@@ -182,6 +158,20 @@ static __always_inline void __ticket_spin_unlock(raw_spinlock_t *lock)
} }
#endif #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) #define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock)
#ifdef CONFIG_PARAVIRT #ifdef CONFIG_PARAVIRT
......
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