/*-
 * Copyright (c) 1982, 1986, 1992 The Regents of the University of California.
 * All rights reserved.
 *
 * %sccs.include.redist.c%
 *
 *	@(#)gmon.h	7.5 (Berkeley) 07/10/92
 */

#ifndef _GMON_H_
#define _GMON_H_

#include <machine/profile.h>

/*
 * Structure prepended to gmon.out profiling data file.
 */
struct gmonhdr {
	u_long	lpc;		/* base pc address of sample buffer */
	u_long	hpc;		/* max pc address of sampled buffer */
	int	ncnt;		/* size of sample buffer (plus this header) */
	int	version;	/* version number */
	int	profrate;	/* profiling clock rate */
	int	spare[3];	/* reserved */
};
#define GMONVERSION	0x00051879

/*
 * 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 with a minimum.
 */
#define ARCDENSITY	2
#define MINARCS		50
#define MAXARCS		((1 << (8 * sizeof(HISTCOUNTER))) - 2)

struct tostruct {
	u_long	selfpc;
	long	count;
	u_short	link;
	u_short pad;
};

/*
 * a raw arc, with pointers to the calling site and 
 * the called site and a count.
 */
struct rawarc {
	u_long	raw_frompc;
	u_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 {
	int		state;
	u_short		*froms;
	struct tostruct	*tos;
	long		tolimit;
	u_long		lowpc;
	u_long		highpc;
	u_long		textsize;
};
extern struct gmonparam _gmonparam;

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

#endif