1 /*-
2  * Copyright (c) 1991 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. [rescinded 22 July 1999]
14  * 4. Neither the name of the University nor the names of its contributors
15  *    may be used to endorse or promote products derived from this software
16  *    without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 /*
32  * This is a modified gmon.c by J.W.Hawtin <oolon@ankh.org>,
33  * 14/8/96 based on the original gmon.c in GCC and the hacked version
34  * solaris 2 sparc version (config/sparc/gmon-sol.c) by Mark Eichin. To do
35  * process profiling on solaris 2.X X86
36  *
37  * It must be used in conjunction with sol2-gc1.asm, which is used to start
38  * and stop process monitoring.
39  *
40  * Differences.
41  *
42  * On Solaris 2 _mcount is called by library functions not mcount, so support
43  * has been added for both.
44  *
45  * Also the prototype for profil() is different
46  *
47  * Solaris 2 does not seem to have char *minbrk whcih allows the setting of
48  * the minimum SBRK region so this code has been removed and lets pray malloc
49  * does not mess it up.
50  *
51  * Notes
52  *
53  * This code could easily be integrated with the original gmon.c and perhaps
54  * should be.
55  */
56 #include "tconfig.h"
57 #include "tsystem.h"
58 #include <fcntl.h> /* for creat() */
59 
60 #ifdef DEBUG
61 #include <stdio.h>
62 #endif
63 
64 static void moncontrol (int);
65 extern void monstartup (char *, char *);
66 extern void _mcleanup (void);
67 extern void internal_mcount (void);
68 
69 
70 struct phdr {
71                 char    *lpc;
72                 char    *hpc;
73                 int     ncnt;
74 };
75 
76 
77 #define HISTFRACTION 2
78 #define HISTCOUNTER unsigned short
79 #define HASHFRACTION 1
80 #define ARCDENSITY 2
81 #define MINARCS 50
82 #define BASEADDRESS 0x8000000 /* On Solaris 2 X86 all executables start here
83 				 and not at 0 */
84 
85 struct tostruct {
86   char *selfpc;
87   long count;
88   unsigned short link;
89 };
90 
91 struct rawarc {
92     unsigned long       raw_frompc;
93     unsigned long       raw_selfpc;
94     long                raw_count;
95 };
96 #define ROUNDDOWN(x,y)  (((x)/(y))*(y))
97 #define ROUNDUP(x,y)    ((((x)+(y)-1)/(y))*(y))
98 
99 /* char *minbrk; */
100 
101     /*
102      *	froms is actually a bunch of unsigned shorts indexing tos
103      */
104 static int		profiling = 3;
105 static unsigned short	*froms;
106 static struct tostruct	*tos = 0;
107 static long		tolimit = 0;
108 static char		*s_lowpc = 0;
109 static char		*s_highpc = 0;
110 static unsigned long	s_textsize = 0;
111 
112 static int	ssiz;
113 static char	*sbuf;
114 static int	s_scale;
115     /* see profil(2) where this is describe (incorrectly) */
116 #define		SCALE_1_TO_1	0x10000L
117 
118 #define	MSG "No space for profiling buffer(s)\n"
119 
120 extern int errno;
121 
122 void
monstartup(char * lowpc,char * highpc)123 monstartup(char *lowpc, char *highpc)
124 {
125     int			monsize;
126     char		*buffer;
127     register int	o;
128 
129 	/*
130 	 *	round lowpc and highpc to multiples of the density we're using
131 	 *	so the rest of the scaling (here and in gprof) stays in ints.
132 	 */
133     lowpc = (char *)
134 	    ROUNDDOWN((unsigned long)lowpc, HISTFRACTION*sizeof(HISTCOUNTER));
135     s_lowpc = lowpc;
136     highpc = (char *)
137 	    ROUNDUP((unsigned long)highpc, HISTFRACTION*sizeof(HISTCOUNTER));
138     s_highpc = highpc;
139     s_textsize = highpc - lowpc;
140     monsize = (s_textsize / HISTFRACTION) + sizeof(struct phdr);
141     buffer = (char *) sbrk( monsize );
142     if ( buffer == (char *) -1 ) {
143 	write( 2 , MSG , sizeof(MSG) );
144 	return;
145     }
146     froms = (unsigned short *) sbrk( s_textsize / HASHFRACTION );
147     if ( froms == (unsigned short *) -1 ) {
148 	write( 2 , MSG , sizeof(MSG) );
149 	froms = 0;
150 	return;
151     }
152     tolimit = s_textsize * ARCDENSITY / 100;
153     if ( tolimit < MINARCS ) {
154 	tolimit = MINARCS;
155     } else if ( tolimit > 65534 ) {
156 	tolimit = 65534;
157     }
158     tos = (struct tostruct *) sbrk( tolimit * sizeof( struct tostruct ) );
159     if ( tos == (struct tostruct *) -1 ) {
160 	write( 2 , MSG , sizeof(MSG) );
161 	froms = 0;
162 	tos = 0;
163 	return;
164     }
165 /*    minbrk = (char *) sbrk(0);*/
166     tos[0].link = 0;
167     sbuf = buffer;
168     ssiz = monsize;
169     ( (struct phdr *) buffer ) -> lpc = lowpc;
170     ( (struct phdr *) buffer ) -> hpc = highpc;
171     ( (struct phdr *) buffer ) -> ncnt = ssiz;
172     monsize -= sizeof(struct phdr);
173     if ( monsize <= 0 )
174 	return;
175     o = highpc - lowpc;
176     if( monsize < o )
177 #ifndef hp300
178 	s_scale = ( (float) monsize / o ) * SCALE_1_TO_1;
179 #else /* avoid floating point */
180     {
181 	int quot = o / monsize;
182 
183 	if (quot >= 0x10000)
184 		s_scale = 1;
185 	else if (quot >= 0x100)
186 		s_scale = 0x10000 / quot;
187 	else if (o >= 0x800000)
188 		s_scale = 0x1000000 / (o / (monsize >> 8));
189 	else
190 		s_scale = 0x1000000 / ((o << 8) / monsize);
191     }
192 #endif
193     else
194 	s_scale = SCALE_1_TO_1;
195     moncontrol(1);
196 }
197 
198 void
_mcleanup(void)199 _mcleanup (void)
200 {
201     int			fd;
202     int			fromindex;
203     int			endfrom;
204     char		*frompc;
205     int			toindex;
206     struct rawarc	rawarc;
207 
208     moncontrol(0);
209     fd = creat( "gmon.out" , 0666 );
210     if ( fd < 0 ) {
211 	perror( "mcount: gmon.out" );
212 	return;
213     }
214 #   ifdef DEBUG
215 	fprintf( stderr , "[mcleanup] sbuf 0x%x ssiz %d\n" , sbuf , ssiz );
216 #   endif /* DEBUG */
217 
218     write( fd , sbuf , ssiz );
219     endfrom = s_textsize / (HASHFRACTION * sizeof(*froms));
220     for ( fromindex = 0 ; fromindex < endfrom ; fromindex++ ) {
221 	if ( froms[fromindex] == 0 ) {
222 	    continue;
223 	}
224 	frompc = s_lowpc + (fromindex * HASHFRACTION * sizeof(*froms));
225 	for (toindex=froms[fromindex]; toindex!=0; toindex=tos[toindex].link) {
226 #	    ifdef DEBUG
227 		fprintf( stderr ,
228 			"[mcleanup] frompc 0x%x selfpc 0x%x count %d\n" ,
229 			frompc , tos[toindex].selfpc , tos[toindex].count );
230 #	    endif /* DEBUG */
231 	    rawarc.raw_frompc = (unsigned long) frompc;
232 	    rawarc.raw_selfpc = (unsigned long) tos[toindex].selfpc;
233 	    rawarc.raw_count = tos[toindex].count;
234 	    write( fd , &rawarc , sizeof rawarc );
235 	}
236     }
237     close( fd );
238 }
239 
240 /* Solaris 2 libraries use _mcount.  */
241 asm(".globl _mcount; _mcount: jmp internal_mcount");
242 /* This is for compatibility with old versions of gcc which used mcount.  */
243 asm(".globl mcount; mcount: jmp internal_mcount");
244 
245 void
internal_mcount(void)246 internal_mcount (void)
247 {
248 	register char			*selfpc;
249 	register unsigned short		*frompcindex;
250 	register struct tostruct	*top;
251 	register struct tostruct	*prevtop;
252 	register long			toindex;
253 	static char already_setup;
254 
255 	/*
256 	 *	find the return address for mcount,
257 	 *	and the return address for mcount's caller.
258 	 */
259 
260 	/* selfpc = pc pushed by mcount call.
261 	   This identifies the function that was just entered.  */
262 	selfpc = (void *) __builtin_return_address (0);
263 	/* frompcindex = pc in preceding frame.
264 	   This identifies the caller of the function just entered.  */
265 	frompcindex = (void *) __builtin_return_address (1);
266 
267 	if(!already_setup) {
268           extern char etext[];
269 	  already_setup = 1;
270 /*	  monstartup(0, etext); */
271 	  monstartup((char*)0x08040000, etext);
272 #ifdef USE_ONEXIT
273 	  on_exit(_mcleanup, 0);
274 #else
275 	  atexit(_mcleanup);
276 #endif
277 	}
278 	/*
279 	 *	check that we are profiling
280 	 *	and that we aren't recursively invoked.
281 	 */
282 	if (profiling) {
283 		goto out;
284 	}
285 	profiling++;
286 	/*
287 	 *	check that frompcindex is a reasonable pc value.
288 	 *	for example:	signal catchers get called from the stack,
289 	 *			not from text space.  too bad.
290 	 */
291 	frompcindex = (unsigned short *)((long)frompcindex - (long)s_lowpc);
292 	if ((unsigned long)frompcindex > s_textsize) {
293 		goto done;
294 	}
295 	frompcindex =
296 	    &froms[((long)frompcindex) / (HASHFRACTION * sizeof(*froms))];
297 	toindex = *frompcindex;
298 	if (toindex == 0) {
299 		/*
300 		 *	first time traversing this arc
301 		 */
302 		toindex = ++tos[0].link;
303 		if (toindex >= tolimit) {
304 			goto overflow;
305 		}
306 		*frompcindex = toindex;
307 		top = &tos[toindex];
308 		top->selfpc = selfpc;
309 		top->count = 1;
310 		top->link = 0;
311 		goto done;
312 	}
313 	top = &tos[toindex];
314 	if (top->selfpc == selfpc) {
315 		/*
316 		 *	arc at front of chain; usual case.
317 		 */
318 		top->count++;
319 		goto done;
320 	}
321 	/*
322 	 *	have to go looking down chain for it.
323 	 *	top points to what we are looking at,
324 	 *	prevtop points to previous top.
325 	 *	we know it is not at the head of the chain.
326 	 */
327 	for (; /* goto done */; ) {
328 		if (top->link == 0) {
329 			/*
330 			 *	top is end of the chain and none of the chain
331 			 *	had top->selfpc == selfpc.
332 			 *	so we allocate a new tostruct
333 			 *	and link it to the head of the chain.
334 			 */
335 			toindex = ++tos[0].link;
336 			if (toindex >= tolimit) {
337 				goto overflow;
338 			}
339 			top = &tos[toindex];
340 			top->selfpc = selfpc;
341 			top->count = 1;
342 			top->link = *frompcindex;
343 			*frompcindex = toindex;
344 			goto done;
345 		}
346 		/*
347 		 *	otherwise, check the next arc on the chain.
348 		 */
349 		prevtop = top;
350 		top = &tos[top->link];
351 		if (top->selfpc == selfpc) {
352 			/*
353 			 *	there it is.
354 			 *	increment its count
355 			 *	move it to the head of the chain.
356 			 */
357 			top->count++;
358 			toindex = prevtop->link;
359 			prevtop->link = top->link;
360 			top->link = *frompcindex;
361 			*frompcindex = toindex;
362 			goto done;
363 		}
364 
365 	}
366 done:
367 	profiling--;
368 	/* and fall through */
369 out:
370 	return;		/* normal return restores saved registers */
371 
372 overflow:
373 	profiling++; /* halt further profiling */
374 #   define	TOLIMIT	"mcount: tos overflow\n"
375 	write(2, TOLIMIT, sizeof(TOLIMIT));
376 	goto out;
377 }
378 
379 /*
380  * Control profiling
381  *	profiling is what mcount checks to see if
382  *	all the data structures are ready.
383  */
384 static void
moncontrol(int mode)385 moncontrol(int mode)
386 {
387     if (mode)
388     {
389       /* start */
390       profil((unsigned short *)(sbuf + sizeof(struct phdr)),
391 	     ssiz - sizeof(struct phdr),
392 	     (long)s_lowpc, s_scale);
393 
394       profiling = 0;
395     } else {
396       /* stop */
397       profil((unsigned short *)0, 0, 0, 0);
398       profiling = 3;
399     }
400 }
401