master
1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1982, 1986, 1992, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * @(#)gmon.h 8.2 (Berkeley) 1/4/94
32 */
33
34#ifndef _SYS_GMON_H_
35#define _SYS_GMON_H_
36
37#include <machine/profile.h>
38
39/*
40 * Structure prepended to gmon.out profiling data file.
41 */
42struct gmonhdr {
43 u_long lpc; /* base pc address of sample buffer */
44 u_long hpc; /* max pc address of sampled buffer */
45 int ncnt; /* size of sample buffer (plus this header) */
46 int version; /* version number */
47 int profrate; /* profiling clock rate */
48 int histcounter_type; /* size (in bits) and sign of HISTCOUNTER */
49 int spare[2]; /* reserved */
50};
51#define GMONVERSION 0x00051879
52
53/*
54 * Type of histogram counters used in the kernel.
55 */
56#ifdef GPROF4
57#define HISTCOUNTER int64_t
58#else
59#define HISTCOUNTER unsigned short
60#endif
61
62/*
63 * Fraction of text space to allocate for histogram counters.
64 * We allocate counters at the same or higher density as function
65 * addresses, so that each counter belongs to a unique function.
66 * A lower density of counters would give less resolution but a
67 * higher density would be wasted.
68 */
69#define HISTFRACTION (FUNCTION_ALIGNMENT / sizeof(HISTCOUNTER) == 0 \
70 ? 1 : FUNCTION_ALIGNMENT / sizeof(HISTCOUNTER))
71
72/*
73 * Fraction of text space to allocate for from hash buckets.
74 * The value of HASHFRACTION is based on the minimum number of bytes
75 * of separation between two subroutine call points in the object code.
76 * Given MIN_SUBR_SEPARATION bytes of separation the value of
77 * HASHFRACTION is calculated as:
78 *
79 * HASHFRACTION = MIN_SUBR_SEPARATION / (2 * sizeof(short) - 1);
80 *
81 * For example, on the VAX, the shortest two call sequence is:
82 *
83 * calls $0,(r0)
84 * calls $0,(r0)
85 *
86 * which is separated by only three bytes, thus HASHFRACTION is
87 * calculated as:
88 *
89 * HASHFRACTION = 3 / (2 * 2 - 1) = 1
90 *
91 * Note that the division above rounds down, thus if MIN_SUBR_FRACTION
92 * is less than three, this algorithm will not work!
93 *
94 * In practice, however, call instructions are rarely at a minimal
95 * distance. Hence, we will define HASHFRACTION to be 2 across all
96 * architectures. This saves a reasonable amount of space for
97 * profiling data structures without (in practice) sacrificing
98 * any granularity.
99 */
100/*
101 * XXX I think the above analysis completely misses the point. I think
102 * the point is that addresses in different functions must hash to
103 * different values. Since the hash is essentially division by
104 * sizeof(unsigned short), the correct formula is:
105 *
106 * HASHFRACTION = MIN_FUNCTION_ALIGNMENT / sizeof(unsigned short)
107 *
108 * Note that he unsigned short here has nothing to do with the one for
109 * HISTFRACTION.
110 *
111 * Hash collisions from a two call sequence don't matter. They get
112 * handled like collisions for calls to different addresses from the
113 * same address through a function pointer.
114 */
115#define HASHFRACTION (FUNCTION_ALIGNMENT / sizeof(unsigned short) == 0 \
116 ? 1 : FUNCTION_ALIGNMENT / sizeof(unsigned short))
117
118/*
119 * percent of text space to allocate for tostructs with a minimum.
120 */
121#define ARCDENSITY 2
122#define MINARCS 50
123
124/*
125 * Limit on the number of arcs to so that arc numbers can be stored in
126 * `*froms' and stored and incremented without overflow in links.
127 */
128#define MAXARCS (((u_long)1 << (8 * sizeof(u_short))) - 2)
129
130struct tostruct {
131 u_long selfpc;
132 long count;
133 u_short link;
134 u_short pad;
135};
136
137/*
138 * a raw arc, with pointers to the calling site and
139 * the called site and a count.
140 */
141struct rawarc {
142 u_long raw_frompc;
143 u_long raw_selfpc;
144 long raw_count;
145};
146
147/*
148 * general rounding functions.
149 */
150#define ROUNDDOWN(x,y) rounddown(x,y)
151#define ROUNDUP(x,y) roundup(x,y)
152
153/*
154 * The profiling data structures are housed in this structure.
155 */
156struct gmonparam {
157 int state;
158 HISTCOUNTER *kcount;
159 u_long kcountsize;
160 u_short *froms;
161 u_long fromssize;
162 struct tostruct *tos;
163 u_long tossize;
164 long tolimit;
165 uintfptr_t lowpc;
166 uintfptr_t highpc;
167 u_long textsize;
168 u_long hashfraction;
169 int profrate; /* XXX wrong type to match gmonhdr */
170 HISTCOUNTER *cputime_count;
171 int cputime_overhead;
172 HISTCOUNTER *mcount_count;
173 int mcount_overhead;
174 int mcount_post_overhead;
175 int mcount_pre_overhead;
176 HISTCOUNTER *mexitcount_count;
177 int mexitcount_overhead;
178 int mexitcount_post_overhead;
179 int mexitcount_pre_overhead;
180 int histcounter_type;
181};
182extern struct gmonparam _gmonparam;
183
184/*
185 * Possible states of profiling.
186 */
187#define GMON_PROF_ON 0
188#define GMON_PROF_BUSY 1
189#define GMON_PROF_ERROR 2
190#define GMON_PROF_OFF 3
191#define GMON_PROF_HIRES 4
192
193/*
194 * Sysctl definitions for extracting profiling information from the kernel.
195 */
196#define GPROF_STATE 0 /* int: profiling enabling variable */
197#define GPROF_COUNT 1 /* struct: profile tick count buffer */
198#define GPROF_FROMS 2 /* struct: from location hash bucket */
199#define GPROF_TOS 3 /* struct: destination/count structure */
200#define GPROF_GMONPARAM 4 /* struct: profiling parameters (see above) */
201
202#ifdef _KERNEL
203
204#define KCOUNT(p,index) \
205 ((p)->kcount[(index) / (HISTFRACTION * sizeof(HISTCOUNTER))])
206#define PC_TO_I(p, pc) ((uintfptr_t)(pc) - (uintfptr_t)(p)->lowpc)
207
208#ifdef GUPROF
209
210#define CALIB_SCALE 1000
211
212extern int cputime_bias;
213
214int cputime(void);
215void nullfunc_loop_profiled(void);
216void nullfunc_profiled(void);
217void startguprof(struct gmonparam *p);
218void stopguprof(struct gmonparam *p);
219
220#else /* !GUPROF */
221
222#define startguprof(p)
223#define stopguprof(p)
224
225#endif /* GUPROF */
226
227void empty_loop(void);
228void kmupetext(uintfptr_t nhighpc);
229void mexitcount(uintfptr_t selfpc);
230void nullfunc(void);
231void nullfunc_loop(void);
232
233#else /* !_KERNEL */
234
235#include <sys/cdefs.h>
236
237__BEGIN_DECLS
238void moncontrol(int);
239void monstartup(u_long, u_long);
240__END_DECLS
241
242#endif /* _KERNEL */
243
244#endif /* !_SYS_GMON_H_ */