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Diffstat (limited to 'arch/tile/include/asm/spinlock_64.h')
-rw-r--r--arch/tile/include/asm/spinlock_64.h138
1 files changed, 0 insertions, 138 deletions
diff --git a/arch/tile/include/asm/spinlock_64.h b/arch/tile/include/asm/spinlock_64.h
deleted file mode 100644
index 5b616ef642a8..000000000000
--- a/arch/tile/include/asm/spinlock_64.h
+++ /dev/null
@@ -1,138 +0,0 @@
-/*
- * Copyright 2011 Tilera Corporation. All Rights Reserved.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation, version 2.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
- * NON INFRINGEMENT. See the GNU General Public License for
- * more details.
- *
- * 64-bit SMP ticket spinlocks, allowing only a single CPU anywhere
- * (the type definitions are in asm/spinlock_types.h)
- */
-
-#ifndef _ASM_TILE_SPINLOCK_64_H
-#define _ASM_TILE_SPINLOCK_64_H
-
-#include <linux/compiler.h>
-
-/* Shifts and masks for the various fields in "lock". */
-#define __ARCH_SPIN_CURRENT_SHIFT 17
-#define __ARCH_SPIN_NEXT_MASK 0x7fff
-#define __ARCH_SPIN_NEXT_OVERFLOW 0x8000
-
-/*
- * Return the "current" portion of a ticket lock value,
- * i.e. the number that currently owns the lock.
- */
-static inline u32 arch_spin_current(u32 val)
-{
- return val >> __ARCH_SPIN_CURRENT_SHIFT;
-}
-
-/*
- * Return the "next" portion of a ticket lock value,
- * i.e. the number that the next task to try to acquire the lock will get.
- */
-static inline u32 arch_spin_next(u32 val)
-{
- return val & __ARCH_SPIN_NEXT_MASK;
-}
-
-/* The lock is locked if a task would have to wait to get it. */
-static inline int arch_spin_is_locked(arch_spinlock_t *lock)
-{
- /* Use READ_ONCE() to ensure that calling this in a loop is OK. */
- u32 val = READ_ONCE(lock->lock);
- return arch_spin_current(val) != arch_spin_next(val);
-}
-
-/* Bump the current ticket so the next task owns the lock. */
-static inline void arch_spin_unlock(arch_spinlock_t *lock)
-{
- wmb(); /* guarantee anything modified under the lock is visible */
- __insn_fetchadd4(&lock->lock, 1U << __ARCH_SPIN_CURRENT_SHIFT);
-}
-
-void arch_spin_lock_slow(arch_spinlock_t *lock, u32 val);
-
-/* Grab the "next" ticket number and bump it atomically.
- * If the current ticket is not ours, go to the slow path.
- * We also take the slow path if the "next" value overflows.
- */
-static inline void arch_spin_lock(arch_spinlock_t *lock)
-{
- u32 val = __insn_fetchadd4(&lock->lock, 1);
- u32 ticket = val & (__ARCH_SPIN_NEXT_MASK | __ARCH_SPIN_NEXT_OVERFLOW);
- if (unlikely(arch_spin_current(val) != ticket))
- arch_spin_lock_slow(lock, ticket);
-}
-
-/* Try to get the lock, and return whether we succeeded. */
-int arch_spin_trylock(arch_spinlock_t *lock);
-
-/*
- * Read-write spinlocks, allowing multiple readers
- * but only one writer.
- *
- * We use fetchadd() for readers, and fetchor() with the sign bit
- * for writers.
- */
-
-#define __WRITE_LOCK_BIT (1 << 31)
-
-static inline int arch_write_val_locked(int val)
-{
- return val < 0; /* Optimize "val & __WRITE_LOCK_BIT". */
-}
-
-extern void __read_lock_failed(arch_rwlock_t *rw);
-
-static inline void arch_read_lock(arch_rwlock_t *rw)
-{
- u32 val = __insn_fetchaddgez4(&rw->lock, 1);
- if (unlikely(arch_write_val_locked(val)))
- __read_lock_failed(rw);
-}
-
-extern void __write_lock_failed(arch_rwlock_t *rw, u32 val);
-
-static inline void arch_write_lock(arch_rwlock_t *rw)
-{
- u32 val = __insn_fetchor4(&rw->lock, __WRITE_LOCK_BIT);
- if (unlikely(val != 0))
- __write_lock_failed(rw, val);
-}
-
-static inline void arch_read_unlock(arch_rwlock_t *rw)
-{
- __insn_mf();
- __insn_fetchadd4(&rw->lock, -1);
-}
-
-static inline void arch_write_unlock(arch_rwlock_t *rw)
-{
- __insn_mf();
- __insn_exch4(&rw->lock, 0); /* Avoid waiting in the write buffer. */
-}
-
-static inline int arch_read_trylock(arch_rwlock_t *rw)
-{
- return !arch_write_val_locked(__insn_fetchaddgez4(&rw->lock, 1));
-}
-
-static inline int arch_write_trylock(arch_rwlock_t *rw)
-{
- u32 val = __insn_fetchor4(&rw->lock, __WRITE_LOCK_BIT);
- if (likely(val == 0))
- return 1;
- if (!arch_write_val_locked(val))
- __insn_fetchand4(&rw->lock, ~__WRITE_LOCK_BIT);
- return 0;
-}
-
-#endif /* _ASM_TILE_SPINLOCK_64_H */