xref: /titanic_50/usr/src/uts/common/sys/turnstile.h (revision 549ec3fff108310966327d1dc9004551b63210b7)
1  /*
2   * CDDL HEADER START
3   *
4   * The contents of this file are subject to the terms of the
5   * Common Development and Distribution License, Version 1.0 only
6   * (the "License").  You may not use this file except in compliance
7   * with the License.
8   *
9   * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10   * or http://www.opensolaris.org/os/licensing.
11   * See the License for the specific language governing permissions
12   * and limitations under the License.
13   *
14   * When distributing Covered Code, include this CDDL HEADER in each
15   * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16   * If applicable, add the following below this CDDL HEADER, with the
17   * fields enclosed by brackets "[]" replaced with your own identifying
18   * information: Portions Copyright [yyyy] [name of copyright owner]
19   *
20   * CDDL HEADER END
21   */
22  /*
23   * Copyright 2003 Sun Microsystems, Inc.  All rights reserved.
24   * Use is subject to license terms.
25   */
26  
27  #ifndef _SYS_TURNSTILE_H
28  #define	_SYS_TURNSTILE_H
29  
30  #pragma ident	"%Z%%M%	%I%	%E% SMI"
31  
32  #include <sys/types.h>
33  #include <sys/time.h>
34  #include <sys/param.h>
35  #include <sys/sleepq.h>
36  #include <sys/mutex.h>
37  #include <sys/lwp_timer_impl.h>
38  
39  #ifdef	__cplusplus
40  extern "C" {
41  #endif
42  
43  #define	TS_WRITER_Q	0	/* writer sleepq (exclusive access to sobj) */
44  #define	TS_READER_Q	1	/* reader sleepq (shared access to sobj) */
45  #define	TS_NUM_Q	2	/* number of sleep queues per turnstile */
46  
47  typedef struct turnstile turnstile_t;
48  struct _sobj_ops;
49  
50  struct turnstile {
51  	turnstile_t	*ts_next;	/* next on hash chain */
52  	turnstile_t	*ts_free;	/* next on freelist */
53  	void		*ts_sobj;	/* s-object threads are blocking on */
54  	int		ts_waiters;	/* number of blocked threads */
55  	pri_t		ts_epri;	/* max priority of blocked threads */
56  	struct _kthread	*ts_inheritor;	/* thread inheriting priority */
57  	turnstile_t	*ts_prioinv;	/* next in inheritor's t_prioinv list */
58  	sleepq_t	ts_sleepq[TS_NUM_Q]; /* read/write sleep queues */
59  };
60  
61  #ifdef	_KERNEL
62  
63  extern turnstile_t *turnstile_lookup(void *);
64  extern void turnstile_exit(void *);
65  extern int turnstile_block(turnstile_t *, int, void *, struct _sobj_ops *,
66      kmutex_t *, lwp_timer_t *);
67  extern void turnstile_wakeup(turnstile_t *, int, int, struct _kthread *);
68  extern void turnstile_change_pri(struct _kthread *, pri_t, pri_t *);
69  extern void turnstile_unsleep(struct _kthread *);
70  extern void turnstile_stay_asleep(struct _kthread *);
71  extern void turnstile_pi_recalc(void);
72  
73  #endif	/* _KERNEL */
74  
75  #ifdef	__cplusplus
76  }
77  #endif
78  
79  #endif	/* _SYS_TURNSTILE_H */
80