author | Florian Westphal <fw@strlen.de> |
Sun, 11 Jan 2009 20:20:11 +0100 | |
changeset 0 | aa628870c1d3 |
permissions | -rw-r--r-- |
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Port of Linux 2.6.28 for use with network simulation cradle.
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/* rwsem.h: R/W semaphores, public interface |
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Port of Linux 2.6.28 for use with network simulation cradle.
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* |
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Port of Linux 2.6.28 for use with network simulation cradle.
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* Written by David Howells (dhowells@redhat.com). |
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Port of Linux 2.6.28 for use with network simulation cradle.
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* Derived from asm-i386/semaphore.h |
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Port of Linux 2.6.28 for use with network simulation cradle.
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*/ |
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Port of Linux 2.6.28 for use with network simulation cradle.
Florian Westphal <fw@strlen.de>
parents:
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Port of Linux 2.6.28 for use with network simulation cradle.
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#ifndef _LINUX_RWSEM_H |
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#define _LINUX_RWSEM_H |
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Port of Linux 2.6.28 for use with network simulation cradle.
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Port of Linux 2.6.28 for use with network simulation cradle.
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#include <linux/linkage.h> |
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Port of Linux 2.6.28 for use with network simulation cradle.
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Port of Linux 2.6.28 for use with network simulation cradle.
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#include <linux/types.h> |
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Port of Linux 2.6.28 for use with network simulation cradle.
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#include <linux/kernel.h> |
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Port of Linux 2.6.28 for use with network simulation cradle.
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#include <asm/system.h> |
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Port of Linux 2.6.28 for use with network simulation cradle.
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#include <asm/atomic.h> |
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Port of Linux 2.6.28 for use with network simulation cradle.
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Port of Linux 2.6.28 for use with network simulation cradle.
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struct rw_semaphore; |
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Port of Linux 2.6.28 for use with network simulation cradle.
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#ifdef CONFIG_RWSEM_GENERIC_SPINLOCK |
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Port of Linux 2.6.28 for use with network simulation cradle.
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#include <linux/rwsem-spinlock.h> /* use a generic implementation */ |
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Port of Linux 2.6.28 for use with network simulation cradle.
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#else |
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Port of Linux 2.6.28 for use with network simulation cradle.
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#include <asm/rwsem.h> /* use an arch-specific implementation */ |
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Port of Linux 2.6.28 for use with network simulation cradle.
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#endif |
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Port of Linux 2.6.28 for use with network simulation cradle.
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/* |
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* lock for reading |
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*/ |
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extern void down_read(struct rw_semaphore *sem); |
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/* |
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* trylock for reading -- returns 1 if successful, 0 if contention |
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*/ |
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extern int down_read_trylock(struct rw_semaphore *sem); |
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/* |
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* lock for writing |
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Port of Linux 2.6.28 for use with network simulation cradle.
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*/ |
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extern void down_write(struct rw_semaphore *sem); |
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Port of Linux 2.6.28 for use with network simulation cradle.
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/* |
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* trylock for writing -- returns 1 if successful, 0 if contention |
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Port of Linux 2.6.28 for use with network simulation cradle.
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*/ |
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Port of Linux 2.6.28 for use with network simulation cradle.
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extern int down_write_trylock(struct rw_semaphore *sem); |
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Port of Linux 2.6.28 for use with network simulation cradle.
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Port of Linux 2.6.28 for use with network simulation cradle.
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/* |
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* release a read lock |
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Port of Linux 2.6.28 for use with network simulation cradle.
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*/ |
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Port of Linux 2.6.28 for use with network simulation cradle.
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extern void up_read(struct rw_semaphore *sem); |
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/* |
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* release a write lock |
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Port of Linux 2.6.28 for use with network simulation cradle.
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*/ |
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Port of Linux 2.6.28 for use with network simulation cradle.
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extern void up_write(struct rw_semaphore *sem); |
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Port of Linux 2.6.28 for use with network simulation cradle.
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/* |
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* downgrade write lock to read lock |
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*/ |
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Port of Linux 2.6.28 for use with network simulation cradle.
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extern void downgrade_write(struct rw_semaphore *sem); |
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#ifdef CONFIG_DEBUG_LOCK_ALLOC |
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/* |
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* nested locking. NOTE: rwsems are not allowed to recurse |
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Port of Linux 2.6.28 for use with network simulation cradle.
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* (which occurs if the same task tries to acquire the same |
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Port of Linux 2.6.28 for use with network simulation cradle.
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* lock instance multiple times), but multiple locks of the |
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Port of Linux 2.6.28 for use with network simulation cradle.
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* same lock class might be taken, if the order of the locks |
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Port of Linux 2.6.28 for use with network simulation cradle.
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* is always the same. This ordering rule can be expressed |
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Port of Linux 2.6.28 for use with network simulation cradle.
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* to lockdep via the _nested() APIs, but enumerating the |
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Port of Linux 2.6.28 for use with network simulation cradle.
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* subclasses that are used. (If the nesting relationship is |
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Port of Linux 2.6.28 for use with network simulation cradle.
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* static then another method for expressing nested locking is |
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Port of Linux 2.6.28 for use with network simulation cradle.
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* the explicit definition of lock class keys and the use of |
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Port of Linux 2.6.28 for use with network simulation cradle.
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* lockdep_set_class() at lock initialization time. |
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Port of Linux 2.6.28 for use with network simulation cradle.
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* See Documentation/lockdep-design.txt for more details.) |
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*/ |
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Port of Linux 2.6.28 for use with network simulation cradle.
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extern void down_read_nested(struct rw_semaphore *sem, int subclass); |
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Port of Linux 2.6.28 for use with network simulation cradle.
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extern void down_write_nested(struct rw_semaphore *sem, int subclass); |
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Port of Linux 2.6.28 for use with network simulation cradle.
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/* |
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* Take/release a lock when not the owner will release it. |
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Port of Linux 2.6.28 for use with network simulation cradle.
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* |
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* [ This API should be avoided as much as possible - the |
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* proper abstraction for this case is completions. ] |
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Port of Linux 2.6.28 for use with network simulation cradle.
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*/ |
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Port of Linux 2.6.28 for use with network simulation cradle.
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extern void down_read_non_owner(struct rw_semaphore *sem); |
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Port of Linux 2.6.28 for use with network simulation cradle.
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extern void up_read_non_owner(struct rw_semaphore *sem); |
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Port of Linux 2.6.28 for use with network simulation cradle.
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parents:
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#else |
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Port of Linux 2.6.28 for use with network simulation cradle.
Florian Westphal <fw@strlen.de>
parents:
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# define down_read_nested(sem, subclass) down_read(sem) |
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Port of Linux 2.6.28 for use with network simulation cradle.
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parents:
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# define down_write_nested(sem, subclass) down_write(sem) |
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Port of Linux 2.6.28 for use with network simulation cradle.
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parents:
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# define down_read_non_owner(sem) down_read(sem) |
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Port of Linux 2.6.28 for use with network simulation cradle.
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parents:
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# define up_read_non_owner(sem) up_read(sem) |
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#endif |
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Port of Linux 2.6.28 for use with network simulation cradle.
Florian Westphal <fw@strlen.de>
parents:
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Port of Linux 2.6.28 for use with network simulation cradle.
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#endif /* _LINUX_RWSEM_H */ |