xref: /netbsd-src/sys/dev/lockstat.h (revision 82d56013d7b633d116a93943de88e08335357a7c)
1 /*	$NetBSD: lockstat.h,v 1.14 2016/01/24 01:01:11 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 2006 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Andrew Doran.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #ifndef _SYS_LOCKSTAT_H_
33 #define _SYS_LOCKSTAT_H_
34 
35 #ifdef _KERNEL_OPT
36 #include "opt_dtrace.h"
37 #include <lockstat.h>
38 #endif
39 
40 #include <sys/types.h>
41 #include <sys/ioccom.h>
42 #include <sys/queue.h>
43 #include <sys/time.h>
44 
45 #if defined(_KERNEL) && defined(__HAVE_CPU_COUNTER)
46 #include <machine/cpu_counter.h>
47 #endif
48 
49 /*
50  * Interface version.  The interface is not designed to provide
51  * compatibility across NetBSD releases.
52  */
53 
54 #define	IOC_LOCKSTAT_GVERSION	_IOR('L', 0, int)
55 
56 #define	LS_VERSION	5
57 
58 /*
59  * Enable request.  We can limit tracing by the call site and by
60  * the lock.  We also specify the number of event buffers to
61  * allocate up front, and what kind of events to track.
62  */
63 
64 #define	IOC_LOCKSTAT_ENABLE	_IOW('L', 1, lsenable_t)
65 
66 #define LE_CALLSITE	0x01		/* track call sites */
67 #define	LE_ONE_CALLSITE	0x02		/* specific call site */
68 #define	LE_ONE_LOCK	0x04		/* specific lock */
69 #define LE_LOCK		0x08		/* track locks */
70 
71 typedef struct lsenable {
72 	uintptr_t	le_csstart;	/* callsite start */
73 	uintptr_t	le_csend;	/* callsite end */
74 	uintptr_t	le_lockstart;	/* lock address start */
75 	uintptr_t	le_lockend;	/* lock address end */
76 	uintptr_t	le_nbufs;	/* buffers to allocate, 0 = default */
77 	u_int		le_flags;	/* request flags */
78 	u_int		le_mask;	/* event mask (LB_*) */
79 } lsenable_t;
80 
81 /*
82  * Disable request.
83  */
84 
85 #define	IOC_LOCKSTAT_DISABLE	_IOR('L', 2, lsdisable_t)
86 
87 typedef struct lsdisable {
88 	size_t		ld_size;	/* buffer space allocated */
89 	struct timespec	ld_time;	/* time spent enabled */
90 	uint64_t	ld_freq[64];	/* counter HZ by CPU number */
91 } lsdisable_t;
92 
93 /*
94  * Event buffers returned from reading from the devices.
95  */
96 
97 /*
98  * Event types, for lockstat_event().  Stored in lb_flags but should be
99  * meaningless to the consumer, also provided with the enable request
100  * in le_mask.
101  */
102 #define	LB_SPIN			0x00000001
103 #define	LB_SLEEP1		0x00000002
104 #define	LB_SLEEP2		0x00000003
105 #define	LB_NEVENT		0x00000003
106 #define	LB_EVENT_MASK		0x000000ff
107 
108 /*
109  * Lock types, the only part of lb_flags that should be inspected.  Also
110  * provided with the enable request in le_mask.
111  */
112 #define	LB_ADAPTIVE_MUTEX	0x00000100
113 #define	LB_SPIN_MUTEX		0x00000200
114 #define	LB_RWLOCK		0x00000300
115 #define	LB_NOPREEMPT		0x00000400
116 #define	LB_KERNEL_LOCK		0x00000500
117 #define	LB_MISC			0x00000600
118 #define	LB_NLOCK		0x00000600
119 #define	LB_LOCK_MASK		0x0000ff00
120 #define	LB_LOCK_SHIFT		8
121 
122 #define	LB_DTRACE		0x00010000
123 
124 typedef struct lsbuf {
125 	union {
126 		LIST_ENTRY(lsbuf) list;
127 		SLIST_ENTRY(lsbuf) slist;
128 		TAILQ_ENTRY(lsbuf) tailq;
129 	} lb_chain;
130 	uintptr_t	lb_lock;		/* lock address */
131 	uintptr_t	lb_callsite;		/* call site */
132 	uint64_t	lb_times[LB_NEVENT];	/* cumulative times */
133 	uint32_t	lb_counts[LB_NEVENT];	/* count of events */
134 	uint16_t	lb_flags;		/* lock type */
135 	uint16_t	lb_cpu;			/* CPU number */
136 } lsbuf_t;
137 
138 /*
139  * Tracing stubs used by lock providers.
140  */
141 
142 #if defined(_KERNEL) && defined(__HAVE_CPU_COUNTER) && NLOCKSTAT > 0
143 
144 #define	LOCKSTAT_EVENT(flag, lock, type, count, time)			\
145 do {									\
146 	if (__predict_false(flag))					\
147 		lockstat_event((uintptr_t)(lock),			\
148 		    (uintptr_t)__builtin_return_address(0),		\
149 		    (type), (count), (time));				\
150 } while (/* CONSTCOND */ 0);
151 
152 #define	LOCKSTAT_EVENT_RA(flag, lock, type, count, time, ra)		\
153 do {									\
154 	if (__predict_false(flag))					\
155 		lockstat_event((uintptr_t)(lock), (uintptr_t)ra,	\
156 		    (type), (count), (time));				\
157 } while (/* CONSTCOND */ 0);
158 
159 #define	LOCKSTAT_TIMER(name)	uint64_t name = 0
160 #define	LOCKSTAT_COUNTER(name)	uint64_t name = 0
161 #define	LOCKSTAT_FLAG(name)	int name
162 #define	LOCKSTAT_ENTER(name)	name = lockstat_enabled
163 #define	LOCKSTAT_EXIT(name)
164 
165 #define	LOCKSTAT_START_TIMER(flag, name)				\
166 do {									\
167 	if (__predict_false(flag))					\
168 		(name) -= cpu_counter();				\
169 } while (/* CONSTCOND */ 0)
170 
171 #define	LOCKSTAT_STOP_TIMER(flag, name)					\
172 do {									\
173 	if (__predict_false(flag))					\
174 		(name) += cpu_counter();				\
175 } while (/* CONSTCOND */ 0)
176 
177 #define	LOCKSTAT_COUNT(name, inc)					\
178 do {									\
179 	(name) += (inc);						\
180 } while (/* CONSTCOND */ 0)
181 
182 void	lockstat_event(uintptr_t, uintptr_t, u_int, u_int, uint64_t);
183 
184 #else
185 
186 #define	LOCKSTAT_FLAG(name)					/* nothing */
187 #define	LOCKSTAT_ENTER(name)					/* nothing */
188 #define	LOCKSTAT_EXIT(name)					/* nothing */
189 #define	LOCKSTAT_EVENT(flag, lock, type, count, time)		/* nothing */
190 #define	LOCKSTAT_EVENT_RA(flag, lock, type, count, time, ra)	/* nothing */
191 #define	LOCKSTAT_TIMER(void)					/* nothing */
192 #define	LOCKSTAT_COUNTER(void)					/* nothing */
193 #define	LOCKSTAT_START_TIMER(flag, void)			/* nothing */
194 #define	LOCKSTAT_STOP_TIMER(flag, void)				/* nothing */
195 #define	LOCKSTAT_COUNT(name, int)				/* nothing */
196 
197 #endif
198 
199 #ifdef KDTRACE_HOOKS
200 extern volatile u_int lockstat_dtrace_enabled;
201 #define KDTRACE_LOCKSTAT_ENABLED lockstat_dtrace_enabled
202 #define LS_COMPRESS(f) \
203     ((((f) & 0x3) | (((f) & 0x700) >> 6)) & (LS_NPROBES - 1))
204 #define	LS_NPROBES	0x20	/* 5 bits */
205 
206 extern uint32_t	lockstat_probemap[];
207 extern void	(*lockstat_probe_func)(uint32_t, uintptr_t, uintptr_t,
208     uintptr_t, uintptr_t, uintptr_t);
209 
210 void		lockstat_probe_stub(uint32_t, uintptr_t, uintptr_t,
211     uintptr_t, uintptr_t, uintptr_t);
212 #else
213 #define KDTRACE_LOCKSTAT_ENABLED 0
214 #endif
215 
216 #if defined(_KERNEL) && NLOCKSTAT > 0
217 extern volatile u_int	lockstat_enabled;
218 extern volatile u_int	lockstat_dev_enabled;
219 
220 #define LOCKSTAT_ENABLED_UPDATE() do { \
221 	lockstat_enabled = lockstat_dev_enabled | KDTRACE_LOCKSTAT_ENABLED; \
222 	membar_producer(); \
223     } while (/*CONSTCOND*/0)
224 #endif
225 
226 #endif	/* _SYS_LOCKSTAT_H_ */
227