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
32#ifndef _SYS_GMON_H_
33#define _SYS_GMON_H_
34
35#include <machine/profile.h>
36
37/*
38 * Structure prepended to gmon.out profiling data file.
39 */
40struct gmonhdr {
41	u_long	lpc;		/* base pc address of sample buffer */
42	u_long	hpc;		/* max pc address of sampled buffer */
43	int	ncnt;		/* size of sample buffer (plus this header) */
44	int	version;	/* version number */
45	int	profrate;	/* profiling clock rate */
46	int	histcounter_type; /* size (in bits) and sign of HISTCOUNTER */
47	int	spare[2];	/* reserved */
48};
49#define GMONVERSION	0x00051879
50
51/*
52 * Type of histogram counters used in the kernel.
53 */
54#ifdef GPROF4
55#define	HISTCOUNTER	int64_t
56#else
57#define	HISTCOUNTER	unsigned short
58#endif
59
60/*
61 * Fraction of text space to allocate for histogram counters.
62 * We allocate counters at the same or higher density as function
63 * addresses, so that each counter belongs to a unique function.
64 * A lower density of counters would give less resolution but a
65 * higher density would be wasted.
66 */
67#define	HISTFRACTION	(FUNCTION_ALIGNMENT / sizeof(HISTCOUNTER) == 0 \
68			 ? 1 : FUNCTION_ALIGNMENT / sizeof(HISTCOUNTER))
69
70/*
71 * Fraction of text space to allocate for from hash buckets.
72 * The value of HASHFRACTION is based on the minimum number of bytes
73 * of separation between two subroutine call points in the object code.
74 * Given MIN_SUBR_SEPARATION bytes of separation the value of
75 * HASHFRACTION is calculated as:
76 *
77 *	HASHFRACTION = MIN_SUBR_SEPARATION / (2 * sizeof(short) - 1);
78 *
79 * For example, on the VAX, the shortest two call sequence is:
80 *
81 *	calls	$0,(r0)
82 *	calls	$0,(r0)
83 *
84 * which is separated by only three bytes, thus HASHFRACTION is
85 * calculated as:
86 *
87 *	HASHFRACTION = 3 / (2 * 2 - 1) = 1
88 *
89 * Note that the division above rounds down, thus if MIN_SUBR_FRACTION
90 * is less than three, this algorithm will not work!
91 *
92 * In practice, however, call instructions are rarely at a minimal
93 * distance.  Hence, we will define HASHFRACTION to be 2 across all
94 * architectures.  This saves a reasonable amount of space for
95 * profiling data structures without (in practice) sacrificing
96 * any granularity.
97 */
98/*
99 * XXX I think the above analysis completely misses the point.  I think
100 * the point is that addresses in different functions must hash to
101 * different values.  Since the hash is essentially division by
102 * sizeof(unsigned short), the correct formula is:
103 *
104 * 	HASHFRACTION = MIN_FUNCTION_ALIGNMENT / sizeof(unsigned short)
105 *
106 * Note that he unsigned short here has nothing to do with the one for
107 * HISTFRACTION.
108 *
109 * Hash collisions from a two call sequence don't matter.  They get
110 * handled like collisions for calls to different addresses from the
111 * same address through a function pointer.
112 */
113#define	HASHFRACTION	(FUNCTION_ALIGNMENT / sizeof(unsigned short) == 0 \
114			 ? 1 : FUNCTION_ALIGNMENT / sizeof(unsigned short))
115
116/*
117 * percent of text space to allocate for tostructs with a minimum.
118 */
119#define ARCDENSITY	2
120#define MINARCS		50
121
122/*
123 * Limit on the number of arcs to so that arc numbers can be stored in
124 * `*froms' and stored and incremented without overflow in links.
125 */
126#define MAXARCS		(((u_long)1 << (8 * sizeof(u_short))) - 2)
127
128struct tostruct {
129	u_long	selfpc;
130	long	count;
131	u_short	link;
132	u_short pad;
133};
134
135/*
136 * a raw arc, with pointers to the calling site and
137 * the called site and a count.
138 */
139struct rawarc {
140	u_long	raw_frompc;
141	u_long	raw_selfpc;
142	long	raw_count;
143};
144
145/*
146 * general rounding functions.
147 */
148#define ROUNDDOWN(x,y)	rounddown(x,y)
149#define ROUNDUP(x,y)	roundup(x,y)
150
151/*
152 * The profiling data structures are housed in this structure.
153 */
154struct gmonparam {
155	int		state;
156	HISTCOUNTER	*kcount;
157	u_long		kcountsize;
158	u_short		*froms;
159	u_long		fromssize;
160	struct tostruct	*tos;
161	u_long		tossize;
162	long		tolimit;
163	uintfptr_t	lowpc;
164	uintfptr_t	highpc;
165	u_long		textsize;
166	u_long		hashfraction;
167	int		profrate;	/* XXX wrong type to match gmonhdr */
168	HISTCOUNTER	*cputime_count;
169	int		cputime_overhead;
170	HISTCOUNTER	*mcount_count;
171	int		mcount_overhead;
172	int		mcount_post_overhead;
173	int		mcount_pre_overhead;
174	HISTCOUNTER	*mexitcount_count;
175	int		mexitcount_overhead;
176	int		mexitcount_post_overhead;
177	int		mexitcount_pre_overhead;
178	int		histcounter_type;
179};
180extern struct gmonparam _gmonparam;
181
182/*
183 * Possible states of profiling.
184 */
185#define	GMON_PROF_ON	0
186#define	GMON_PROF_BUSY	1
187#define	GMON_PROF_ERROR	2
188#define	GMON_PROF_OFF	3
189#define	GMON_PROF_HIRES	4
190
191/*
192 * Sysctl definitions for extracting profiling information from the kernel.
193 */
194#define	GPROF_STATE	0	/* int: profiling enabling variable */
195#define	GPROF_COUNT	1	/* struct: profile tick count buffer */
196#define	GPROF_FROMS	2	/* struct: from location hash bucket */
197#define	GPROF_TOS	3	/* struct: destination/count structure */
198#define	GPROF_GMONPARAM	4	/* struct: profiling parameters (see above) */
199
200#ifdef _KERNEL
201
202#define	KCOUNT(p,index) \
203	((p)->kcount[(index) / (HISTFRACTION * sizeof(HISTCOUNTER))])
204#define	PC_TO_I(p, pc)	((uintfptr_t)(pc) - (uintfptr_t)(p)->lowpc)
205
206#ifdef GUPROF
207
208#define	CALIB_SCALE	1000
209
210extern int	cputime_bias;
211
212int	cputime(void);
213void	nullfunc_loop_profiled(void);
214void	nullfunc_profiled(void);
215void	startguprof(struct gmonparam *p);
216void	stopguprof(struct gmonparam *p);
217
218#else /* !GUPROF */
219
220#define	startguprof(p)
221#define	stopguprof(p)
222
223#endif /* GUPROF */
224
225void	empty_loop(void);
226void	kmupetext(uintfptr_t nhighpc);
227void	mexitcount(uintfptr_t selfpc);
228void	nullfunc(void);
229void	nullfunc_loop(void);
230
231#else /* !_KERNEL */
232
233#include <sys/cdefs.h>
234
235__BEGIN_DECLS
236void	moncontrol(int);
237void	monstartup(u_long, u_long);
238__END_DECLS
239
240#endif /* _KERNEL */
241
242#endif /* !_SYS_GMON_H_ */
243