xref: /illumos-gate/usr/src/uts/common/sys/clock_impl.h (revision 777222b7)
1d3d50737SRafael Vanoni /*
2d3d50737SRafael Vanoni  * CDDL HEADER START
3d3d50737SRafael Vanoni  *
4d3d50737SRafael Vanoni  * The contents of this file are subject to the terms of the
5d3d50737SRafael Vanoni  * Common Development and Distribution License (the "License").
6d3d50737SRafael Vanoni  * You may not use this file except in compliance with the License.
7d3d50737SRafael Vanoni  *
8d3d50737SRafael Vanoni  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9d3d50737SRafael Vanoni  * or http://www.opensolaris.org/os/licensing.
10d3d50737SRafael Vanoni  * See the License for the specific language governing permissions
11d3d50737SRafael Vanoni  * and limitations under the License.
12d3d50737SRafael Vanoni  *
13d3d50737SRafael Vanoni  * When distributing Covered Code, include this CDDL HEADER in each
14d3d50737SRafael Vanoni  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15d3d50737SRafael Vanoni  * If applicable, add the following below this CDDL HEADER, with the
16d3d50737SRafael Vanoni  * fields enclosed by brackets "[]" replaced with your own identifying
17d3d50737SRafael Vanoni  * information: Portions Copyright [yyyy] [name of copyright owner]
18d3d50737SRafael Vanoni  *
19d3d50737SRafael Vanoni  * CDDL HEADER END
20d3d50737SRafael Vanoni  */
21d3d50737SRafael Vanoni 
22d3d50737SRafael Vanoni /*
23*777222b7SRafael Vanoni  * Copyright (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved.
24d3d50737SRafael Vanoni  */
25d3d50737SRafael Vanoni 
26d3d50737SRafael Vanoni #ifndef	_SYS_CLOCK_IMPL_H
27d3d50737SRafael Vanoni #define	_SYS_CLOCK_IMPL_H
28d3d50737SRafael Vanoni 
29d3d50737SRafael Vanoni #ifdef	__cplusplus
30d3d50737SRafael Vanoni extern "C" {
31d3d50737SRafael Vanoni #endif
32d3d50737SRafael Vanoni 
33d3d50737SRafael Vanoni #if (defined(_KERNEL) || defined(_KMEMUSER))
34d3d50737SRafael Vanoni #include <sys/types.h>
35d3d50737SRafael Vanoni #include <sys/cpuvar.h>
36d3d50737SRafael Vanoni #include <sys/cyclic.h>
37d3d50737SRafael Vanoni #include <sys/time.h>
38d3d50737SRafael Vanoni 
39d3d50737SRafael Vanoni /*
40d3d50737SRafael Vanoni  * Default clock rate in Hz.
41d3d50737SRafael Vanoni  */
42579a6895SRafael Vanoni #define	HZ_DEFAULT			(100)
43d3d50737SRafael Vanoni 
44d3d50737SRafael Vanoni /*
45d3d50737SRafael Vanoni  * Thresholds over which we switch between event and cyclic driven lbolt. The
46d3d50737SRafael Vanoni  * current default values were derived experimentally and will keep the
47d3d50737SRafael Vanoni  * system on event driven mode when idle and respond to activity around the
48d3d50737SRafael Vanoni  * lbolt DDI functions by switching to cyclic mode.
49d3d50737SRafael Vanoni  */
50d3d50737SRafael Vanoni #define	LBOLT_THRESH_CALLS		(75)
51d3d50737SRafael Vanoni #define	LBOLT_THRESH_INTERVAL		(1)
52d3d50737SRafael Vanoni 
53d3d50737SRafael Vanoni /*
54d3d50737SRafael Vanoni  * Both lbolt_cpu_t and lbolt_info_t are cache line sized and aligned,
55d3d50737SRafael Vanoni  * please take that in consideration if modifying these.
56d3d50737SRafael Vanoni  */
57d3d50737SRafael Vanoni typedef struct lbolt_cpu {
58d3d50737SRafael Vanoni 	int64_t lbc_counter;	/* number of calls to the DDI lbolt routines */
59d3d50737SRafael Vanoni 	int64_t lbc_cnt_start;	/* beggining of the cnt interval (in ticks) */
60d3d50737SRafael Vanoni 	char lbc_pad[CPU_CACHE_COHERENCE_SIZE - (2 * sizeof (int64_t))];
61d3d50737SRafael Vanoni } lbolt_cpu_t;
62d3d50737SRafael Vanoni 
63d3d50737SRafael Vanoni typedef struct lbolt_info {
64579a6895SRafael Vanoni 	union {
65579a6895SRafael Vanoni 		cyclic_id_t lbi_cyclic_id;	/* lbolt's cyclic id */
66579a6895SRafael Vanoni 		int64_t lbi_id_pad;		/* 64bit padding */
67579a6895SRafael Vanoni 	} id;
68d3d50737SRafael Vanoni 	int64_t lbi_thresh_calls;	/* max calls per interval */
69d3d50737SRafael Vanoni 	int64_t lbi_thresh_interval;	/* interval window for the # of calls */
70*777222b7SRafael Vanoni 	int64_t lbi_debug_ts;		/* last time we dropped into kmdb */
71*777222b7SRafael Vanoni 	int64_t lbi_debug_time;		/* time spent in the debugger */
72*777222b7SRafael Vanoni 	int64_t lbi_internal;		/* lbolt source when on cyclic mode */
73d3d50737SRafael Vanoni 	uint32_t lbi_token;		/* synchronize cyclic mode switch */
74d3d50737SRafael Vanoni 	boolean_t lbi_cyc_deactivate;	/* lbolt_cyclic self deactivation */
75d3d50737SRafael Vanoni 	int64_t lbi_cyc_deac_start;	/* deactivation interval */
76d3d50737SRafael Vanoni } lbolt_info_t;
77d3d50737SRafael Vanoni 
7883e866b9SRafael Vanoni extern int64_t lbolt_bootstrap(void);
79d3d50737SRafael Vanoni extern int64_t lbolt_event_driven(void);
80d3d50737SRafael Vanoni extern int64_t lbolt_cyclic_driven(void);
81d3d50737SRafael Vanoni extern int64_t (*lbolt_hybrid)(void);
82d3d50737SRafael Vanoni extern uint_t lbolt_ev_to_cyclic(caddr_t, caddr_t);
83d3d50737SRafael Vanoni 
84d3d50737SRafael Vanoni extern void lbolt_softint_add(void);
85d3d50737SRafael Vanoni extern void lbolt_softint_post(void);
86d3d50737SRafael Vanoni 
87d3d50737SRafael Vanoni extern void lbolt_debug_entry(void);
88d3d50737SRafael Vanoni extern void lbolt_debug_return(void);
89d3d50737SRafael Vanoni 
90d3d50737SRafael Vanoni extern lbolt_info_t *lb_info;
91d3d50737SRafael Vanoni 
92d3d50737SRafael Vanoni /*
931b7f7204SRafael Vanoni  * LBOLT_WAITFREE{,64} provide a non-waiting version of lbolt.
94d3d50737SRafael Vanoni  */
951b7f7204SRafael Vanoni #define	LBOLT_WAITFREE64						\
9683e866b9SRafael Vanoni 	(lbolt_hybrid == lbolt_bootstrap ? 0 :				\
97d3d50737SRafael Vanoni 	(lbolt_hybrid == lbolt_event_driven ?                           \
98d3d50737SRafael Vanoni 	    ((gethrtime_waitfree()/nsec_per_tick) -			\
99d3d50737SRafael Vanoni 	    lb_info->lbi_debug_time) :					\
10083e866b9SRafael Vanoni 	    (lb_info->lbi_internal - lb_info->lbi_debug_time)))
101d3d50737SRafael Vanoni 
1021b7f7204SRafael Vanoni #define	LBOLT_WAITFREE		(clock_t)LBOLT_WAITFREE64
1031b7f7204SRafael Vanoni 
104d3d50737SRafael Vanoni /*
1051b7f7204SRafael Vanoni  * LBOLT_FASTPATH{,64} should *only* be used where the cost of calling the
1061b7f7204SRafael Vanoni  * DDI lbolt routines affects performance. This is currently only used by
1071b7f7204SRafael Vanoni  * the TCP/IP code and will be removed once it's no longer required.
108d3d50737SRafael Vanoni  */
1091b7f7204SRafael Vanoni #define	LBOLT_FASTPATH64						\
11083e866b9SRafael Vanoni 	(lbolt_hybrid == lbolt_cyclic_driven ?				\
11183e866b9SRafael Vanoni 	    (lb_info->lbi_internal - lb_info->lbi_debug_time) :		\
112*777222b7SRafael Vanoni 	    lbolt_event_driven())
1131b7f7204SRafael Vanoni 
1141b7f7204SRafael Vanoni #define	LBOLT_FASTPATH		(clock_t)LBOLT_FASTPATH64
115d3d50737SRafael Vanoni 
116d3d50737SRafael Vanoni /*
1171b7f7204SRafael Vanoni  * LBOLT_NO_ACCOUNT{,64} is used by lbolt consumers who fire at a periodic
1181b7f7204SRafael Vanoni  * rate, such as clock(), for which the lbolt usage statistics are not updated.
1191b7f7204SRafael Vanoni  * This is especially important for consumers whose rate may be modified by
120d3d50737SRafael Vanoni  * the user, resulting in an unaccounted for increase in activity around the
121d3d50737SRafael Vanoni  * lbolt routines that could cause a mode switch.
122d3d50737SRafael Vanoni  */
1231b7f7204SRafael Vanoni #define	LBOLT_NO_ACCOUNT64						\
12483e866b9SRafael Vanoni 	(lbolt_hybrid == lbolt_bootstrap ? 0 :				\
125d3d50737SRafael Vanoni 	(lbolt_hybrid == lbolt_event_driven ?				\
126d3d50737SRafael Vanoni 	    ((gethrtime()/nsec_per_tick) - lb_info->lbi_debug_time) :	\
12783e866b9SRafael Vanoni 	    (lb_info->lbi_internal - lb_info->lbi_debug_time)))
128d3d50737SRafael Vanoni 
1291b7f7204SRafael Vanoni #define	LBOLT_NO_ACCOUNT	(clock_t)LBOLT_NO_ACCOUNT64
1301b7f7204SRafael Vanoni 
131d3d50737SRafael Vanoni #endif	/* _KERNEL || _KMEMUSER */
132d3d50737SRafael Vanoni 
133d3d50737SRafael Vanoni #ifdef	__cplusplus
134d3d50737SRafael Vanoni }
135d3d50737SRafael Vanoni #endif
136d3d50737SRafael Vanoni 
137d3d50737SRafael Vanoni #endif /* _SYS_CLOCK_IMPL_H */