179 lines
6.7 KiB
C
179 lines
6.7 KiB
C
#ifndef __LINUX_SPINLOCK_H
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#define __LINUX_SPINLOCK_H
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#include <linux/config.h>
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#include <asm/system.h>
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/*
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* These are the generic versions of the spinlocks and read-write
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* locks..
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*/
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#define spin_lock_irqsave(lock, flags) do { local_irq_save(flags); spin_lock(lock); } while (0)
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#define spin_lock_irq(lock) do { local_irq_disable(); spin_lock(lock); } while (0)
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#define spin_lock_bh(lock) do { local_bh_disable(); spin_lock(lock); } while (0)
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#define read_lock_irqsave(lock, flags) do { local_irq_save(flags); read_lock(lock); } while (0)
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#define read_lock_irq(lock) do { local_irq_disable(); read_lock(lock); } while (0)
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#define read_lock_bh(lock) do { local_bh_disable(); read_lock(lock); } while (0)
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#define write_lock_irqsave(lock, flags) do { local_irq_save(flags); write_lock(lock); } while (0)
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#define write_lock_irq(lock) do { local_irq_disable(); write_lock(lock); } while (0)
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#define write_lock_bh(lock) do { local_bh_disable(); write_lock(lock); } while (0)
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#define spin_unlock_irqrestore(lock, flags) do { spin_unlock(lock); local_irq_restore(flags); } while (0)
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#define spin_unlock_irq(lock) do { spin_unlock(lock); local_irq_enable(); } while (0)
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#define spin_unlock_bh(lock) do { spin_unlock(lock); local_bh_enable(); } while (0)
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#define read_unlock_irqrestore(lock, flags) do { read_unlock(lock); local_irq_restore(flags); } while (0)
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#define read_unlock_irq(lock) do { read_unlock(lock); local_irq_enable(); } while (0)
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#define read_unlock_bh(lock) do { read_unlock(lock); local_bh_enable(); } while (0)
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#define write_unlock_irqrestore(lock, flags) do { write_unlock(lock); local_irq_restore(flags); } while (0)
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#define write_unlock_irq(lock) do { write_unlock(lock); local_irq_enable(); } while (0)
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#define write_unlock_bh(lock) do { write_unlock(lock); local_bh_enable(); } while (0)
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#define spin_trylock_bh(lock) ({ int __r; local_bh_disable();\
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__r = spin_trylock(lock); \
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if (!__r) local_bh_enable(); \
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__r; })
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/* Must define these before including other files, inline functions need them */
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#include <linux/stringify.h>
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#define LOCK_SECTION_NAME \
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".text.lock." __stringify(KBUILD_BASENAME)
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#define LOCK_SECTION_START(extra) \
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".subsection 1\n\t" \
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extra \
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".ifndef " LOCK_SECTION_NAME "\n\t" \
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LOCK_SECTION_NAME ":\n\t" \
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".endif\n\t"
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#define LOCK_SECTION_END \
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".previous\n\t"
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#ifdef CONFIG_SMP
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#include <asm/spinlock.h>
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#elif !defined(spin_lock_init) /* !SMP and spin_lock_init not previously
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defined (e.g. by including asm/spinlock.h */
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#define DEBUG_SPINLOCKS 0 /* 0 == no debugging, 1 == maintain lock state, 2 == full debug */
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#if (DEBUG_SPINLOCKS < 1)
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#define atomic_dec_and_lock(atomic,lock) atomic_dec_and_test(atomic)
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#define ATOMIC_DEC_AND_LOCK
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/*
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* Your basic spinlocks, allowing only a single CPU anywhere
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*
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* Some older gcc versions had a nasty bug with empty initializers.
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* (XXX: could someone please confirm whether egcs 1.1 still has this bug?)
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*/
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#if (__GNUC__ > 2 || __GNUC_MINOR__ > 95)
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typedef struct { } spinlock_t;
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#define SPIN_LOCK_UNLOCKED (spinlock_t) { }
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#else
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typedef struct { int gcc_is_buggy; } spinlock_t;
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#define SPIN_LOCK_UNLOCKED (spinlock_t) { 0 }
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#endif
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#define spin_lock_init(lock) do { } while(0)
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#define spin_lock(lock) (void)(lock) /* Not "unused variable". */
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#define spin_is_locked(lock) (0)
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#define spin_trylock(lock) ({1; })
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#define spin_unlock_wait(lock) do { } while(0)
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#define spin_unlock(lock) do { } while(0)
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#elif (DEBUG_SPINLOCKS < 2)
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typedef struct {
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volatile unsigned long lock;
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} spinlock_t;
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#define SPIN_LOCK_UNLOCKED (spinlock_t) { 0 }
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#define spin_lock_init(x) do { (x)->lock = 0; } while (0)
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#define spin_is_locked(lock) (test_bit(0,(lock)))
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#define spin_trylock(lock) (!test_and_set_bit(0,(lock)))
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#define spin_lock(x) do { (x)->lock = 1; } while (0)
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#define spin_unlock_wait(x) do { } while (0)
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#define spin_unlock(x) do { (x)->lock = 0; } while (0)
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#else /* (DEBUG_SPINLOCKS >= 2) */
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typedef struct {
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volatile unsigned long lock;
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volatile unsigned int babble;
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const char *module;
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} spinlock_t;
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#define SPIN_LOCK_UNLOCKED (spinlock_t) { 0, 25, __BASE_FILE__ }
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#include <linux/kernel.h>
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#define spin_lock_init(x) do { (x)->lock = 0; } while (0)
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#define spin_is_locked(lock) (test_bit(0,(lock)))
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#define spin_trylock(lock) (!test_and_set_bit(0,(lock)))
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#define spin_lock(x) do {unsigned long __spinflags; save_flags(__spinflags); cli(); if ((x)->lock&&(x)->babble) {printk("%s:%d: spin_lock(%s:%p) already locked\n", __BASE_FILE__,__LINE__, (x)->module, (x));(x)->babble--;} (x)->lock = 1; restore_flags(__spinflags);} while (0)
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#define spin_unlock_wait(x) do {unsigned long __spinflags; save_flags(__spinflags); cli(); if ((x)->lock&&(x)->babble) {printk("%s:%d: spin_unlock_wait(%s:%p) deadlock\n", __BASE_FILE__,__LINE__, (x)->module, (x));(x)->babble--;} restore_flags(__spinflags);} while (0)
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#define spin_unlock(x) do {unsigned long __spinflags; save_flags(__spinflags); cli(); if (!(x)->lock&&(x)->babble) {printk("%s:%d: spin_unlock(%s:%p) not locked\n", __BASE_FILE__,__LINE__, (x)->module, (x));(x)->babble--;} (x)->lock = 0; restore_flags(__spinflags);} while (0)
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#endif /* DEBUG_SPINLOCKS */
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/*
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* Read-write spinlocks, allowing multiple readers
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* but only one writer.
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*
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* NOTE! it is quite common to have readers in interrupts
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* but no interrupt writers. For those circumstances we
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* can "mix" irq-safe locks - any writer needs to get a
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* irq-safe write-lock, but readers can get non-irqsafe
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* read-locks.
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*
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* Some older gcc versions had a nasty bug with empty initializers.
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* (XXX: could someone please confirm whether egcs 1.1 still has this bug?)
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*/
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#if (__GNUC__ > 2 || __GNUC_MINOR__ > 91)
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typedef struct { } rwlock_t;
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#define RW_LOCK_UNLOCKED (rwlock_t) { }
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#else
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typedef struct { int gcc_is_buggy; } rwlock_t;
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#define RW_LOCK_UNLOCKED (rwlock_t) { 0 }
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#endif
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#define rwlock_init(lock) do { } while(0)
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#define read_lock(lock) (void)(lock) /* Not "unused variable". */
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#define read_unlock(lock) (void)(lock) /* Not "unused variable". */
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#define write_lock(lock) (void)(lock) /* Not "unused variable". */
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#define write_unlock(lock) do { } while(0)
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#endif /* !SMP */
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/* "lock on reference count zero" */
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#ifndef ATOMIC_DEC_AND_LOCK
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#include <asm/atomic.h>
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extern int atomic_dec_and_lock(atomic_t *atomic, spinlock_t *lock);
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#endif
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#ifdef CONFIG_SMP
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#include <linux/cache.h>
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typedef union {
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spinlock_t lock;
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char fill_up[(SMP_CACHE_BYTES)];
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} spinlock_cacheline_t __attribute__ ((aligned(SMP_CACHE_BYTES)));
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#else /* SMP */
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typedef struct {
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spinlock_t lock;
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} spinlock_cacheline_t;
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#endif
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#endif /* __LINUX_SPINLOCK_H */
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