aboutsummaryrefslogtreecommitdiff
path: root/gmon/sys/gmon.h
blob: af0582a3717085b531954ef1b94587f79acb3e66 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
/*-
 * Copyright (c) 1982, 1986, 1992, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)gmon.h	8.2 (Berkeley) 1/4/94
 */

#ifndef	_SYS_GMON_H
#define	_SYS_GMON_H	1

#include <features.h>

#include <sys/types.h>

/*
 * See gmon_out.h for gmon.out format.
 */

/* structure emitted by "gcc -a".  This must match struct bb in
   gcc/libgcc2.c.  It is OK for gcc to declare a longer structure as
   long as the members below are present.  */
struct __bb
{
  long			zero_word;
  const char		*filename;
  long			*counts;
  long			ncounts;
  struct __bb		*next;
  const unsigned long	*addresses;
};

extern struct __bb *__bb_head;

/*
 * histogram counters are unsigned shorts (according to the kernel).
 */
#define	HISTCOUNTER	unsigned short

/*
 * fraction of text space to allocate for histogram counters here, 1/2
 */
#define	HISTFRACTION	2

/*
 * Fraction of text space to allocate for from hash buckets.
 * The value of HASHFRACTION is based on the minimum number of bytes
 * of separation between two subroutine call points in the object code.
 * Given MIN_SUBR_SEPARATION bytes of separation the value of
 * HASHFRACTION is calculated as:
 *
 *	HASHFRACTION = MIN_SUBR_SEPARATION / (2 * sizeof(short) - 1);
 *
 * For example, on the VAX, the shortest two call sequence is:
 *
 *	calls	$0,(r0)
 *	calls	$0,(r0)
 *
 * which is separated by only three bytes, thus HASHFRACTION is
 * calculated as:
 *
 *	HASHFRACTION = 3 / (2 * 2 - 1) = 1
 *
 * Note that the division above rounds down, thus if MIN_SUBR_FRACTION
 * is less than three, this algorithm will not work!
 *
 * In practice, however, call instructions are rarely at a minimal
 * distance.  Hence, we will define HASHFRACTION to be 2 across all
 * architectures.  This saves a reasonable amount of space for
 * profiling data structures without (in practice) sacrificing
 * any granularity.
 */
#define	HASHFRACTION	2

/*
 * Percent of text space to allocate for tostructs.
 * This is a heuristic; we will fail with a warning when profiling programs
 * with a very large number of very small functions, but that's
 * normally OK.
 * 2 is probably still a good value for normal programs.
 * Profiling a test case with 64000 small functions will work if
 * you raise this value to 3 and link statically (which bloats the
 * text size, thus raising the number of arcs expected by the heuristic).
 */
#define ARCDENSITY	3

/*
 * Always allocate at least this many tostructs.  This
 * hides the inadequacy of the ARCDENSITY heuristic, at least
 * for small programs.
 *
 * Value can be overridden at runtime by glibc.gmon.minarcs tunable.
 */
#define MINARCS		50

/*
 * The type used to represent indices into gmonparam.tos[].
 */
#define	ARCINDEX	unsigned long

/*
 * Maximum number of arcs we want to allow.
 * Used to be max representable value of ARCINDEX minus 2, but now
 * that ARCINDEX is a long, that's too large; we don't really want
 * to allow a 48 gigabyte table.
 *
 * Value can be overridden at runtime by glibc.gmon.maxarcs tunable.
 */
#define MAXARCS		(1 << 20)

struct tostruct {
	unsigned long	selfpc;
	long		count;
	ARCINDEX	link;
};

/*
 * a raw arc, with pointers to the calling site and
 * the called site and a count.
 */
struct rawarc {
	unsigned long	raw_frompc;
	unsigned long	raw_selfpc;
	long		raw_count;
};

/*
 * general rounding functions.
 */
#define ROUNDDOWN(x,y)	(((x)/(y))*(y))
#define ROUNDUP(x,y)	((((x)+(y)-1)/(y))*(y))

/*
 * The profiling data structures are housed in this structure.
 */
struct gmonparam {
	long int	state;
	unsigned short	*kcount;
	unsigned long	kcountsize;
	ARCINDEX	*froms;
	unsigned long	fromssize;
	struct tostruct	*tos;
	unsigned long	tossize;
	long		tolimit;
	unsigned long	lowpc;
	unsigned long	highpc;
	unsigned long	textsize;
	unsigned long	hashfraction;
	long		log_hashfraction;
};

/*
 * Possible states of profiling.
 */
#define	GMON_PROF_ON	0
#define	GMON_PROF_BUSY	1
#define	GMON_PROF_ERROR	2
#define	GMON_PROF_OFF	3

/*
 * Sysctl definitions for extracting profiling information from the kernel.
 */
#define	GPROF_STATE	0	/* int: profiling enabling variable */
#define	GPROF_COUNT	1	/* struct: profile tick count buffer */
#define	GPROF_FROMS	2	/* struct: from location hash bucket */
#define	GPROF_TOS	3	/* struct: destination/count structure */
#define	GPROF_GMONPARAM	4	/* struct: profiling parameters (see above) */

__BEGIN_DECLS

/* Set up data structures and start profiling.  */
extern void __monstartup (unsigned long __lowpc, unsigned long __highpc) __THROW;
extern void monstartup (unsigned long __lowpc, unsigned long __highpc) __THROW;

/* Clean up profiling and write out gmon.out.  */
extern void _mcleanup (void) __THROW;

__END_DECLS

#endif /* sys/gmon.h */