diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2008-07-21 09:40:26 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-07-21 09:40:26 -0700 |
| commit | f8b71a3a92d69cb1c9c2162f9235d3dd550e4aa0 (patch) | |
| tree | d0853186f33314a6e45903876d0e94d1619fcca9 /include/asm-sparc/rwsem.h | |
| parent | 42a77a1b8fe4fd78cf8d8fccbaac918bbe888192 (diff) | |
| parent | e4f25060b87a627f5cda84b8134911d43c919458 (diff) | |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6: (44 commits)
sparc: Remove Sparc's asm-offsets for sclow.S
sparc64: Update defconfig.
sparc64: Add Niagara2 RNG driver.
sparc64: Add missing hypervisor service group numbers.
sparc64: Remove 4MB and 512K base page size options.
sparc64: Convert to generic helpers for IPI function calls.
sparc: Use new '%pS' infrastructure to print symbols.
sparc32: fix init.c allnoconfig build error
sparc64: Config category "Processor type and features" absent
sparc: arch/sparc/kernel/apc.c to unlocked_ioctl
sparc: join the remaining header files
sparc: merge header files with trivial differences
sparc: when header files are equal use asm-sparc version
sparc: copy sparc64 specific files to asm-sparc
sparc: Merge asm-sparc{,64}/asi.h
sparc: export openprom.h to userspace
sparc: Merge asm-sparc{,64}/types.h
sparc: Merge asm-sparc{,64}/termios.h
sparc: Merge asm-sparc{,64}/termbits.h
sparc: Merge asm-sparc{,64}/setup.h
...
Diffstat (limited to 'include/asm-sparc/rwsem.h')
| -rw-r--r-- | include/asm-sparc/rwsem.h | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/include/asm-sparc/rwsem.h b/include/asm-sparc/rwsem.h new file mode 100644 index 00000000000..1dc129ac2fe --- /dev/null +++ b/include/asm-sparc/rwsem.h @@ -0,0 +1,84 @@ +/* + * rwsem.h: R/W semaphores implemented using CAS + * + * Written by David S. Miller (davem@redhat.com), 2001. + * Derived from asm-i386/rwsem.h + */ +#ifndef _SPARC64_RWSEM_H +#define _SPARC64_RWSEM_H + +#ifndef _LINUX_RWSEM_H +#error "please don't include asm/rwsem.h directly, use linux/rwsem.h instead" +#endif + +#ifdef __KERNEL__ + +#include <linux/list.h> +#include <linux/spinlock.h> +#include <asm/rwsem-const.h> + +struct rwsem_waiter; + +struct rw_semaphore { + signed int count; + spinlock_t wait_lock; + struct list_head wait_list; +#ifdef CONFIG_DEBUG_LOCK_ALLOC + struct lockdep_map dep_map; +#endif +}; + +#ifdef CONFIG_DEBUG_LOCK_ALLOC +# define __RWSEM_DEP_MAP_INIT(lockname) , .dep_map = { .name = #lockname } +#else +# define __RWSEM_DEP_MAP_INIT(lockname) +#endif + +#define __RWSEM_INITIALIZER(name) \ +{ RWSEM_UNLOCKED_VALUE, SPIN_LOCK_UNLOCKED, LIST_HEAD_INIT((name).wait_list) \ + __RWSEM_DEP_MAP_INIT(name) } + +#define DECLARE_RWSEM(name) \ + struct rw_semaphore name = __RWSEM_INITIALIZER(name) + +extern void __init_rwsem(struct rw_semaphore *sem, const char *name, + struct lock_class_key *key); + +#define init_rwsem(sem) \ +do { \ + static struct lock_class_key __key; \ + \ + __init_rwsem((sem), #sem, &__key); \ +} while (0) + +extern void __down_read(struct rw_semaphore *sem); +extern int __down_read_trylock(struct rw_semaphore *sem); +extern void __down_write(struct rw_semaphore *sem); +extern int __down_write_trylock(struct rw_semaphore *sem); +extern void __up_read(struct rw_semaphore *sem); +extern void __up_write(struct rw_semaphore *sem); +extern void __downgrade_write(struct rw_semaphore *sem); + +static inline void __down_write_nested(struct rw_semaphore *sem, int subclass) +{ + __down_write(sem); +} + +static inline int rwsem_atomic_update(int delta, struct rw_semaphore *sem) +{ + return atomic_add_return(delta, (atomic_t *)(&sem->count)); +} + +static inline void rwsem_atomic_add(int delta, struct rw_semaphore *sem) +{ + atomic_add(delta, (atomic_t *)(&sem->count)); +} + +static inline int rwsem_is_locked(struct rw_semaphore *sem) +{ + return (sem->count != 0); +} + +#endif /* __KERNEL__ */ + +#endif /* _SPARC64_RWSEM_H */ |
