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31 * @(#)gmon.h 8.2 (Berkeley) 1/4/94
38 #include <machine/profile.h>
41 * Structure prepended to gmon.out profiling data file.
44 u_long lpc; /* base pc address of sample buffer */
45 u_long hpc; /* max pc address of sampled buffer */
46 int ncnt; /* size of sample buffer (plus this header) */
47 int version; /* version number */
48 int profrate; /* profiling clock rate */
49 int histcounter_type; /* size (in bits) and sign of HISTCOUNTER */
50 int spare[2]; /* reserved */
52 #define GMONVERSION 0x00051879
55 * Type of histogram counters used in the kernel.
58 #define HISTCOUNTER int64_t
60 #define HISTCOUNTER unsigned short
64 * Fraction of text space to allocate for histogram counters.
65 * We allocate counters at the same or higher density as function
66 * addresses, so that each counter belongs to a unique function.
67 * A lower density of counters would give less resolution but a
68 * higher density would be wasted.
70 #define HISTFRACTION (FUNCTION_ALIGNMENT / sizeof(HISTCOUNTER) == 0 \
71 ? 1 : FUNCTION_ALIGNMENT / sizeof(HISTCOUNTER))
74 * Fraction of text space to allocate for from hash buckets.
75 * The value of HASHFRACTION is based on the minimum number of bytes
76 * of separation between two subroutine call points in the object code.
77 * Given MIN_SUBR_SEPARATION bytes of separation the value of
78 * HASHFRACTION is calculated as:
80 * HASHFRACTION = MIN_SUBR_SEPARATION / (2 * sizeof(short) - 1);
82 * For example, on the VAX, the shortest two call sequence is:
87 * which is separated by only three bytes, thus HASHFRACTION is
90 * HASHFRACTION = 3 / (2 * 2 - 1) = 1
92 * Note that the division above rounds down, thus if MIN_SUBR_FRACTION
93 * is less than three, this algorithm will not work!
95 * In practice, however, call instructions are rarely at a minimal
96 * distance. Hence, we will define HASHFRACTION to be 2 across all
97 * architectures. This saves a reasonable amount of space for
98 * profiling data structures without (in practice) sacrificing
102 * XXX I think the above analysis completely misses the point. I think
103 * the point is that addresses in different functions must hash to
104 * different values. Since the hash is essentially division by
105 * sizeof(unsigned short), the correct formula is:
107 * HASHFRACTION = MIN_FUNCTION_ALIGNMENT / sizeof(unsigned short)
109 * Note that he unsigned short here has nothing to do with the one for
112 * Hash collisions from a two call sequence don't matter. They get
113 * handled like collisions for calls to different addresses from the
114 * same address through a function pointer.
116 #define HASHFRACTION (FUNCTION_ALIGNMENT / sizeof(unsigned short) == 0 \
117 ? 1 : FUNCTION_ALIGNMENT / sizeof(unsigned short))
120 * percent of text space to allocate for tostructs with a minimum.
126 * Limit on the number of arcs to so that arc numbers can be stored in
127 * `*froms' and stored and incremented without overflow in links.
129 #define MAXARCS (((u_long)1 << (8 * sizeof(u_short))) - 2)
139 * a raw arc, with pointers to the calling site and
140 * the called site and a count.
149 * general rounding functions.
151 #define ROUNDDOWN(x,y) rounddown(x,y)
152 #define ROUNDUP(x,y) roundup(x,y)
155 * The profiling data structures are housed in this structure.
163 struct tostruct *tos;
170 int profrate; /* XXX wrong type to match gmonhdr */
171 HISTCOUNTER *cputime_count;
172 int cputime_overhead;
173 HISTCOUNTER *mcount_count;
175 int mcount_post_overhead;
176 int mcount_pre_overhead;
177 HISTCOUNTER *mexitcount_count;
178 int mexitcount_overhead;
179 int mexitcount_post_overhead;
180 int mexitcount_pre_overhead;
181 int histcounter_type;
183 extern struct gmonparam _gmonparam;
186 * Possible states of profiling.
188 #define GMON_PROF_ON 0
189 #define GMON_PROF_BUSY 1
190 #define GMON_PROF_ERROR 2
191 #define GMON_PROF_OFF 3
192 #define GMON_PROF_HIRES 4
195 * Sysctl definitions for extracting profiling information from the kernel.
197 #define GPROF_STATE 0 /* int: profiling enabling variable */
198 #define GPROF_COUNT 1 /* struct: profile tick count buffer */
199 #define GPROF_FROMS 2 /* struct: from location hash bucket */
200 #define GPROF_TOS 3 /* struct: destination/count structure */
201 #define GPROF_GMONPARAM 4 /* struct: profiling parameters (see above) */
205 #define KCOUNT(p,index) \
206 ((p)->kcount[(index) / (HISTFRACTION * sizeof(HISTCOUNTER))])
207 #define PC_TO_I(p, pc) ((uintfptr_t)(pc) - (uintfptr_t)(p)->lowpc)
211 #define CALIB_SCALE 1000
213 extern int cputime_bias;
216 void nullfunc_loop_profiled(void);
217 void nullfunc_profiled(void);
218 void startguprof(struct gmonparam *p);
219 void stopguprof(struct gmonparam *p);
223 #define startguprof(p)
224 #define stopguprof(p)
228 void empty_loop(void);
229 void kmupetext(uintfptr_t nhighpc);
230 void mexitcount(uintfptr_t selfpc);
232 void nullfunc_loop(void);
236 #include <sys/cdefs.h>
239 void moncontrol(int);
240 void monstartup(u_long, u_long);
245 #endif /* !_SYS_GMON_H_ */