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