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#ifndef __LINUX_BIT_SPINLOCK_H
#define __LINUX_BIT_SPINLOCK_H
#include <linux/kernel.h>
#include <linux/preempt.h>
#include <linux/futex.h>
static inline void bit_spin_lock(int nr, unsigned long *_addr)
{
u32 mask, *addr = ((u32 *) _addr) + (nr / 32), v;
nr &= 31;
mask = 1U << nr;
while (1) {
v = __atomic_fetch_or(addr, mask, __ATOMIC_ACQUIRE);
if (!(v & mask))
break;
futex(addr, FUTEX_WAIT|FUTEX_PRIVATE_FLAG, v, NULL, NULL, 0);
}
}
static inline void bit_spin_wake(int nr, unsigned long *_addr)
{
u32 *addr = ((u32 *) _addr) + (nr / 32);
futex(addr, FUTEX_WAKE|FUTEX_PRIVATE_FLAG, INT_MAX, NULL, NULL, 0);
}
static inline void bit_spin_unlock(int nr, unsigned long *_addr)
{
u32 mask, *addr = ((u32 *) _addr) + (nr / 32);
nr &= 31;
mask = 1U << nr;
__atomic_and_fetch(addr, ~mask, __ATOMIC_RELEASE);
futex(addr, FUTEX_WAKE|FUTEX_PRIVATE_FLAG, INT_MAX, NULL, NULL, 0);
}
#endif /* __LINUX_BIT_SPINLOCK_H */
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