e5f4633c39
which included commits to RCS files with non-trunk default branches. git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@5 b08c6af1-5177-4d33-ba66-4b1c6b8b522a
40 lines
1.1 KiB
C
40 lines
1.1 KiB
C
/* ------------------------------- **
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** Atomic lock for ALPHA **
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** ------------------------------- */
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/* This code is stolen from the Linux kernel */
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typedef struct { unsigned long a[100]; } __dummy_lock_t;
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#define __dummy_lock(lock) (*(__dummy_lock_t *)(lock))
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/*
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Memory barrier in Alpha machines
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*/
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#define mb() \
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__asm__ __volatile__("mb": : :"memory")
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#define INIT_LOCK(LOCK_VAR) ((LOCK_VAR) = 0)
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#define TRY_LOCK(LOCK_PTR) (!_test_and_set_bit(0,(volatile void *)(LOCK_PTR)))
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#define LOCK(LOCK_VAR) _spin_lock((volatile void *)&(LOCK_VAR))
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#define IS_LOCKED(LOCK_VAR) ((LOCK_VAR) != 0)
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#define IS_UNLOCKED(LOCK_VAR) ((LOCK_VAR) == 0)
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/* We need to support a memory barrier on Alphas */
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#define UNLOCK(LOCK_VAR) { mb(); LOCK_VAR = 0; }
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typedef struct {
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volatile int write_lock:1, read_counter:31;
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} /*__attribute__((aligned(32)))*/ rwlock_t;
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#define RW_LOCK_UNLOCKED (rwlock_t) { 0, 0 }
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#define READ_LOCK(X) _read_lock(&(X))
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#define READ_UNLOCK(X) _read_unlock(&(X))
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#define WRITE_LOCK(X) _write_lock(&(X))
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#define WRITE_UNLOCK(X) _write_unlock(&(X))
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#define INIT_RWLOCK(RW) (RW) = RW_LOCK_UNLOCKED
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