386BSD 0.0 development
[unix-history] / usr / src / sys.386bsd / kern / subr_mcount.c
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1/*
2 * Copyright (c) 1982, 1986 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. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 * @(#)subr_mcount.c 7.10 (Berkeley) 5/7/91
34 */
35
36#ifdef GPROF
37#include "gprof.h"
38#include "param.h"
39#include "systm.h"
40#include "malloc.h"
41
42/*
43 * Froms is actually a bunch of unsigned shorts indexing tos
44 */
45int profiling = 3;
46u_short *froms;
47struct tostruct *tos = 0;
48long tolimit = 0;
49char *s_lowpc = (char *)KERNBASE;
50extern char etext;
51char *s_highpc = &etext;
52u_long s_textsize = 0;
53int ssiz;
54u_short *sbuf;
55u_short *kcount;
56
57kmstartup()
58{
59 u_long fromssize, tossize;
60
61 /*
62 * Round lowpc and highpc to multiples of the density we're using
63 * so the rest of the scaling (here and in gprof) stays in ints.
64 */
65 s_lowpc = (char *)
66 ROUNDDOWN((unsigned)s_lowpc, HISTFRACTION*sizeof (HISTCOUNTER));
67 s_highpc = (char *)
68 ROUNDUP((unsigned)s_highpc, HISTFRACTION*sizeof (HISTCOUNTER));
69 s_textsize = s_highpc - s_lowpc;
70 printf("Profiling kernel, s_textsize=%d [%x..%x]\n",
71 s_textsize, s_lowpc, s_highpc);
72 ssiz = (s_textsize / HISTFRACTION) + sizeof (struct phdr);
73 sbuf = (u_short *)malloc(ssiz, M_GPROF, M_WAITOK);
74 if (sbuf == 0) {
75 printf("No space for monitor buffer(s)\n");
76 return;
77 }
78 bzero(sbuf, ssiz);
79 fromssize = s_textsize / HASHFRACTION;
80 froms = (u_short *)malloc(fromssize, M_GPROF, M_NOWAIT);
81 if (froms == 0) {
82 printf("No space for monitor buffer(s)\n");
83 free(sbuf, M_GPROF);
84 sbuf = 0;
85 return;
86 }
87 bzero(froms, fromssize);
88 tolimit = s_textsize * ARCDENSITY / 100;
89 if (tolimit < MINARCS)
90 tolimit = MINARCS;
91 else if (tolimit > (0xffff - 1))
92 tolimit = 0xffff - 1;
93 tossize = tolimit * sizeof (struct tostruct);
94 tos = (struct tostruct *)malloc(tossize, M_GPROF, M_WAITOK);
95 if (tos == 0) {
96 printf("No space for monitor buffer(s)\n");
97 free(sbuf, M_GPROF), sbuf = 0;
98 free(froms, M_GPROF), froms = 0;
99 return;
100 }
101 bzero(tos, tossize);
102 tos[0].link = 0;
103 ((struct phdr *)sbuf)->lpc = s_lowpc;
104 ((struct phdr *)sbuf)->hpc = s_highpc;
105 ((struct phdr *)sbuf)->ncnt = ssiz;
106 kcount = (u_short *)(((int)sbuf) + sizeof (struct phdr));
107}
108
109/*
110 * This routine is massaged so that it may be jsb'ed to on vax.
111 */
112asm(".text");
113asm("#the beginning of mcount()");
114asm(".data");
115mcount()
116{
117 register char *selfpc; /* r11 => r5 */
118 register u_short *frompcindex; /* r10 => r4 */
119 register struct tostruct *top; /* r9 => r3 */
120 register struct tostruct *prevtop; /* r8 => r2 */
121 register long toindex; /* r7 => r1 */
122 static int s;
123
124 asm(" .text"); /* make sure we're in text space */
125 /*
126 * Check that we are profiling.
127 */
128 if (profiling)
129 goto out;
130 /*
131 * Find the return address for mcount,
132 * and the return address for mcount's caller.
133 */
134#ifdef lint
135 selfpc = (char *)0;
136 frompcindex = 0;
137#else
138 ; /* avoid label botch */
139#ifdef __GNUC__
140#if defined(vax)
141 Fix Me!!
142#endif
143#if defined(tahoe)
144 Fix Me!!
145#endif
146#if defined(hp300)
147 /*
148 * selfpc = pc pushed by mcount jsr,
149 * frompcindex = pc pushed by jsr into self.
150 * In GCC the caller's stack frame has already been built so we
151 * have to chase a6 to find caller's raddr. This assumes that all
152 * routines we are profiling were built with GCC and that all
153 * profiled routines use link/unlk.
154 */
155 asm("movl a6@(4),%0" : "=r" (selfpc));
156 asm("movl a6@(0)@(4),%0" : "=r" (frompcindex));
157#endif
158#else
159#if defined(vax)
160 asm(" movl (sp), r11"); /* selfpc = ... (jsb frame) */
161 asm(" movl 16(fp), r10"); /* frompcindex = (calls frame) */
162#endif
163#if defined(tahoe)
164 asm(" movl -8(fp),r12"); /* selfpc = callf frame */
165 asm(" movl (fp),r11");
166 asm(" movl -8(r11),r11"); /* frompcindex = 1 callf frame back */
167#endif
168#if defined(hp300)
169 Fix Me!!
170#endif
171#endif /* not __GNUC__ */
172#endif /* not lint */
173 /*
174 * Insure that we cannot be recursively invoked.
175 * this requires that splhigh() and splx() below
176 * do NOT call mcount!
177 */
178#if defined(hp300)
179 asm("movw sr,%0" : "=g" (s));
180 asm("movw #0x2700,sr");
181#else
182 s = splhigh();
183#endif
184 /*
185 * Check that frompcindex is a reasonable pc value.
186 * For example: signal catchers get called from the stack,
187 * not from text space. too bad.
188 */
189 frompcindex = (u_short *)((long)frompcindex - (long)s_lowpc);
190 if ((u_long)frompcindex > s_textsize)
191 goto done;
192 frompcindex =
193 &froms[((long)frompcindex) / (HASHFRACTION * sizeof (*froms))];
194 toindex = *frompcindex;
195 if (toindex == 0) {
196 /*
197 * First time traversing this arc
198 */
199 toindex = ++tos[0].link;
200 if (toindex >= tolimit)
201 goto overflow;
202 *frompcindex = toindex;
203 top = &tos[toindex];
204 top->selfpc = selfpc;
205 top->count = 1;
206 top->link = 0;
207 goto done;
208 }
209 top = &tos[toindex];
210 if (top->selfpc == selfpc) {
211 /*
212 * Arc at front of chain; usual case.
213 */
214 top->count++;
215 goto done;
216 }
217 /*
218 * Have to go looking down chain for it.
219 * Top points to what we are looking at,
220 * prevtop points to previous top.
221 * We know it is not at the head of the chain.
222 */
223 for (; /* goto done */; ) {
224 if (top->link == 0) {
225 /*
226 * Top is end of the chain and none of the chain
227 * had top->selfpc == selfpc.
228 * So we allocate a new tostruct
229 * and link it to the head of the chain.
230 */
231 toindex = ++tos[0].link;
232 if (toindex >= tolimit)
233 goto overflow;
234 top = &tos[toindex];
235 top->selfpc = selfpc;
236 top->count = 1;
237 top->link = *frompcindex;
238 *frompcindex = toindex;
239 goto done;
240 }
241 /*
242 * Otherwise, check the next arc on the chain.
243 */
244 prevtop = top;
245 top = &tos[top->link];
246 if (top->selfpc == selfpc) {
247 /*
248 * There it is, increment its count and
249 * move it to the head of the chain.
250 */
251 top->count++;
252 toindex = prevtop->link;
253 prevtop->link = top->link;
254 top->link = *frompcindex;
255 *frompcindex = toindex;
256 goto done;
257 }
258
259 }
260done:
261#if defined(hp300)
262 asm("movw %0,sr" : : "g" (s));
263#else
264 splx(s);
265#endif
266 /* and fall through */
267out:
268#if defined(vax)
269 asm(" rsb");
270#endif
271 return;
272overflow:
273 profiling = 3;
274 printf("mcount: tos overflow\n");
275 goto out;
276}
277asm(".text");
278asm("#the end of mcount()");
279asm(".data");
280#endif