/*      $OpenBSD: gmon.h,v 1.12 2025/07/16 16:22:58 deraadt Exp $       */
/*      $NetBSD: gmon.h,v 1.5 1996/04/09 20:55:30 cgd Exp $     */

/*-
 * 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.
 * 3. 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_

#include <sys/queue.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     totarc;         /* space used by arcs */
        int     spare[2];       /* 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         *kcount;
        u_long          kcountsize;
        u_short         *froms;
        u_long          fromssize;
        struct tostruct *tos;
        u_long          tossize;
        long            tolimit;
        u_long          lowpc;
        u_long          highpc;
        u_long          textsize;
        u_long          hashfraction;
        void            *outbuf;
        size_t          outbuflen;
        void            *rawarcs;
        int             dirfd;
        SLIST_ENTRY(gmonparam)  list;
};

/*
 * 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) */

#ifdef _KERNEL
extern int gmoninit;            /* Is the kernel ready for being profiled? */

#else /* !_KERNEL */

#include <sys/cdefs.h>

__BEGIN_DECLS
extern struct gmonparam _gmonparam;
void    _mcleanup(void);
void    _monstartup(u_long, u_long);
void    moncontrol(int);
struct gmonparam *_gmon_alloc(void);
__END_DECLS

#endif /* !_KERNEL */

#endif /* !_SYS_GMON_H_ */