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 */ 40 struct 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) 127 128 struct 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 */ 139 struct 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 */ 154 struct 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 }; 180 extern 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 209 210 extern int cputime_bias; 211 212 int cputime(void); 213 void nullfunc_loop_profiled(void); 214 void nullfunc_profiled(void); 215 void startguprof(struct gmonparam *p); 216 void stopguprof(struct gmonparam *p); 217 218 #else /* !GUPROF */ 219 220 #define startguprof(p) 221 #define stopguprof(p) 222 223 #endif /* GUPROF */ 224 225 void empty_loop(void); 226 void kmupetext(uintfptr_t nhighpc); 227 void mexitcount(uintfptr_t selfpc); 228 void nullfunc(void); 229 void nullfunc_loop(void); 230 231 #else /* !_KERNEL */ 232 233 #include <sys/cdefs.h> 234 235 __BEGIN_DECLS 236 void moncontrol(int); 237 void monstartup(u_long, u_long); 238 __END_DECLS 239 240 #endif /* _KERNEL */ 241 242 #endif /* !_SYS_GMON_H_ */ 243