Differential D47450 Diff 146068 sys/sys/_rwlock.h

Changeset View

Standalone View

sys/sys/_rwlock.h

	Show All 22 Lines
	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY			* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF			* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	* SUCH DAMAGE.			* SUCH DAMAGE.
	*/			*/

	#ifndef _SYS__RWLOCK_H_			#ifndef _SYS__RWLOCK_H_
	#define _SYS__RWLOCK_H_			#define _SYS__RWLOCK_H_

				#include <sys/_types.h>
				#include <sys/_lock.h>
	#include <machine/param.h>			#include <machine/param.h>

	/*			/*
	* Reader/writer lock.			* Reader/writer lock.
	*			*
	* All reader/writer lock implementations must always have a member			* All reader/writer lock implementations must always have a member
	* called rw_lock. Other locking primitive structures are not allowed to			* called rw_lock. Other locking primitive structures are not allowed to
	* use this name for their members.			* use this name for their members.
	* If this rule needs to change, the bits in the reader/writer lock			* If this rule needs to change, the bits in the reader/writer lock
	* implementation must be modified appropriately.			* implementation must be modified appropriately.
	*/			*/
	struct rwlock {			struct rwlock {
	struct lock_object lock_object;			struct lock_object lock_object;
	volatile uintptr_t rw_lock;			volatile __uintptr_t rw_lock;
	};			};

	/*			/*
	* Members of struct rwlock_padalign must mirror members of struct rwlock.			* Members of struct rwlock_padalign must mirror members of struct rwlock.
	* rwlock_padalign rwlocks can use the rwlock(9) API transparently without			* rwlock_padalign rwlocks can use the rwlock(9) API transparently without
	* modification.			* modification.
	* Pad-aligned rwlocks used within structures should generally be the			* Pad-aligned rwlocks used within structures should generally be the
	* first member of the struct. Otherwise, the compiler can generate			* first member of the struct. Otherwise, the compiler can generate
	* additional padding for the struct to keep a correct alignment for			* additional padding for the struct to keep a correct alignment for
	* the rwlock.			* the rwlock.
	*/			*/
	struct rwlock_padalign {			struct rwlock_padalign {
	struct lock_object lock_object;			struct lock_object lock_object;
	volatile uintptr_t rw_lock;			volatile __uintptr_t rw_lock;
	} __aligned(CACHE_LINE_SIZE);			} __aligned(CACHE_LINE_SIZE);

	#endif /* !_SYS__RWLOCK_H_ */			#endif /* !_SYS__RWLOCK_H_ */