1/* $NetBSD: lockstat.h,v 1.15 2022/02/27 14:16:12 riastradh 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
42#include <sys/ioccom.h>
43#include <sys/lock.h>
44#include <sys/queue.h>
45#include <sys/time.h>
46
47#if defined(_KERNEL) && defined(__HAVE_CPU_COUNTER)
48#include <machine/cpu_counter.h>
49#endif
50
51/*
52 * Interface version. The interface is not designed to provide
53 * compatibility across NetBSD releases.
54 */
55
56#define IOC_LOCKSTAT_GVERSION _IOR('L', 0, int)
57
58#define LS_VERSION 5
59
60/*
61 * Enable request. We can limit tracing by the call site and by
62 * the lock. We also specify the number of event buffers to
63 * allocate up front, and what kind of events to track.
64 */
65
66#define IOC_LOCKSTAT_ENABLE _IOW('L', 1, lsenable_t)
67
68#define LE_CALLSITE 0x01 /* track call sites */
69#define LE_ONE_CALLSITE 0x02 /* specific call site */
70#define LE_ONE_LOCK 0x04 /* specific lock */
71#define LE_LOCK 0x08 /* track locks */
72
73typedef struct lsenable {
74 uintptr_t le_csstart; /* callsite start */
75 uintptr_t le_csend; /* callsite end */
76 uintptr_t le_lockstart; /* lock address start */
77 uintptr_t le_lockend; /* lock address end */
78 uintptr_t le_nbufs; /* buffers to allocate, 0 = default */
79 u_int le_flags; /* request flags */
80 u_int le_mask; /* event mask (LB_*) */
81} lsenable_t;
82
83/*
84 * Disable request.
85 */
86
87#define IOC_LOCKSTAT_DISABLE _IOR('L', 2, lsdisable_t)
88
89typedef struct lsdisable {
90 size_t ld_size; /* buffer space allocated */
91 struct timespec ld_time; /* time spent enabled */
92 uint64_t ld_freq[64]; /* counter HZ by CPU number */
93} lsdisable_t;
94
95/*
96 * Event buffers returned from reading from the devices.
97 */
98
99/*
100 * Event types, for lockstat_event(). Stored in lb_flags but should be
101 * meaningless to the consumer, also provided with the enable request
102 * in le_mask.
103 */
104#define LB_SPIN 0x00000001
105#define LB_SLEEP1 0x00000002
106#define LB_SLEEP2 0x00000003
107#define LB_NEVENT 0x00000003
108#define LB_EVENT_MASK 0x000000ff
109
110/*
111 * Lock types, the only part of lb_flags that should be inspected. Also
112 * provided with the enable request in le_mask.
113 */
114#define LB_ADAPTIVE_MUTEX 0x00000100
115#define LB_SPIN_MUTEX 0x00000200
116#define LB_RWLOCK 0x00000300
117#define LB_NOPREEMPT 0x00000400
118#define LB_KERNEL_LOCK 0x00000500
119#define LB_MISC 0x00000600
120#define LB_NLOCK 0x00000600
121#define LB_LOCK_MASK 0x0000ff00
122#define LB_LOCK_SHIFT 8
123
124#define LB_DTRACE 0x00010000
125
126typedef struct lsbuf {
127 union {
128 LIST_ENTRY(lsbuf) list;
129 SLIST_ENTRY(lsbuf) slist;
130 TAILQ_ENTRY(lsbuf) tailq;
131 } lb_chain;
132 uintptr_t lb_lock; /* lock address */
133 uintptr_t lb_callsite; /* call site */
134 uint64_t lb_times[LB_NEVENT]; /* cumulative times */
135 uint32_t lb_counts[LB_NEVENT]; /* count of events */
136 uint16_t lb_flags; /* lock type */
137 uint16_t lb_cpu; /* CPU number */
138} lsbuf_t;
139
140/*
141 * Tracing stubs used by lock providers.
142 */
143
144#if defined(_KERNEL) && defined(__HAVE_CPU_COUNTER) && NLOCKSTAT > 0
145
146#define LOCKSTAT_EVENT(flag, lock, type, count, time) \
147do { \
148 if (__predict_false(flag)) \
149 lockstat_event((uintptr_t)(lock), \
150 (uintptr_t)__builtin_return_address(0), \
151 (type), (count), (time)); \
152} while (/* CONSTCOND */ 0);
153
154#define LOCKSTAT_EVENT_RA(flag, lock, type, count, time, ra) \
155do { \
156 if (__predict_false(flag)) \
157 lockstat_event((uintptr_t)(lock), (uintptr_t)ra, \
158 (type), (count), (time)); \
159} while (/* CONSTCOND */ 0);
160
161#define LOCKSTAT_TIMER(name) uint64_t name = 0
162#define LOCKSTAT_COUNTER(name) uint64_t name = 0
163#define LOCKSTAT_FLAG(name) int name
164#define LOCKSTAT_ENTER(name) name = atomic_load_relaxed(&lockstat_enabled)
165#define LOCKSTAT_EXIT(name)
166
167#define LOCKSTAT_START_TIMER(flag, name) \
168do { \
169 if (__predict_false(flag)) \
170 (name) -= cpu_counter(); \
171} while (/* CONSTCOND */ 0)
172
173#define LOCKSTAT_STOP_TIMER(flag, name) \
174do { \
175 if (__predict_false(flag)) \
176 (name) += cpu_counter(); \
177} while (/* CONSTCOND */ 0)
178
179#define LOCKSTAT_COUNT(name, inc) \
180do { \
181 (name) += (inc); \
182} while (/* CONSTCOND */ 0)
183
184void lockstat_event(uintptr_t, uintptr_t, u_int, u_int, uint64_t);
185
186#else
187
188#define LOCKSTAT_FLAG(name) /* nothing */
189#define LOCKSTAT_ENTER(name) /* nothing */
190#define LOCKSTAT_EXIT(name) /* nothing */
191#define LOCKSTAT_EVENT(flag, lock, type, count, time) /* nothing */
192#define LOCKSTAT_EVENT_RA(flag, lock, type, count, time, ra) /* nothing */
193#define LOCKSTAT_TIMER(void) /* nothing */
194#define LOCKSTAT_COUNTER(void) /* nothing */
195#define LOCKSTAT_START_TIMER(flag, void) /* nothing */
196#define LOCKSTAT_STOP_TIMER(flag, void) /* nothing */
197#define LOCKSTAT_COUNT(name, int) /* nothing */
198
199#endif
200
201#ifdef KDTRACE_HOOKS
202extern volatile u_int lockstat_dtrace_enabled;
203#define KDTRACE_LOCKSTAT_ENABLED lockstat_dtrace_enabled
204#define LS_COMPRESS(f) \
205 ((((f) & 0x3) | (((f) & 0x700) >> 6)) & (LS_NPROBES - 1))
206#define LS_NPROBES 0x20 /* 5 bits */
207
208extern uint32_t lockstat_probemap[];
209extern void (*lockstat_probe_func)(uint32_t, uintptr_t, uintptr_t,
210 uintptr_t, uintptr_t, uintptr_t);
211
212void lockstat_probe_stub(uint32_t, uintptr_t, uintptr_t,
213 uintptr_t, uintptr_t, uintptr_t);
214#else
215#define KDTRACE_LOCKSTAT_ENABLED 0
216#endif
217
218#if defined(_KERNEL) && NLOCKSTAT > 0
219extern __cpu_simple_lock_t lockstat_enabled_lock;
220extern volatile u_int lockstat_enabled;
221extern volatile u_int lockstat_dev_enabled;
222
223#define LOCKSTAT_ENABLED_UPDATE_BEGIN() do \
224{ \
225 __cpu_simple_lock(&lockstat_enabled_lock); \
226} while (/*CONSTCOND*/0)
227
228#define LOCKSTAT_ENABLED_UPDATE_END() do \
229{ \
230 atomic_store_relaxed(&lockstat_enabled, \
231 lockstat_dev_enabled | KDTRACE_LOCKSTAT_ENABLED); \
232 __cpu_simple_unlock(&lockstat_enabled_lock); \
233} while (/*CONSTCOND*/0)
234
235#endif
236
237#endif /* _SYS_LOCKSTAT_H_ */