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1 /*
2 * Copyright (c) 2000-2008 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
29 /*-
30 * Copyright (c) 1982, 1986, 1993
31 * The Regents of the University of California. All rights reserved.
32 *
33 * Redistribution and use in source and binary forms, with or without
34 * modification, are permitted provided that the following conditions
35 * are met:
36 * 1. Redistributions of source code must retain the above copyright
37 * notice, this list of conditions and the following disclaimer.
38 * 2. Redistributions in binary form must reproduce the above copyright
39 * notice, this list of conditions and the following disclaimer in the
40 * documentation and/or other materials provided with the distribution.
41 * 3. All advertising materials mentioning features or use of this software
42 * must display the following acknowledgement:
43 * This product includes software developed by the University of
44 * California, Berkeley and its contributors.
45 * 4. Neither the name of the University nor the names of its contributors
46 * may be used to endorse or promote products derived from this software
47 * without specific prior written permission.
48 *
49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59 * SUCH DAMAGE.
60 *
61 * @(#)subr_prof.c 8.3 (Berkeley) 9/23/93
62 */
63
64 #ifdef GPROF
65 #include <libkern/kernel_mach_header.h>
66 #endif
67
68 #include <sys/param.h>
69 #include <sys/systm.h>
70 #include <sys/kernel.h>
71 #include <sys/proc_internal.h>
72 #include <sys/user.h>
73 #include <machine/machine_routines.h>
74
75 #include <sys/mount_internal.h>
76 #include <sys/sysproto.h>
77
78 #include <mach/mach_types.h>
79 #include <kern/kern_types.h>
80 #include <kern/cpu_number.h>
81 #include <kern/kalloc.h>
82
83 #ifdef GPROF
84 #include <sys/malloc.h>
85 #include <sys/gmon.h>
86
87 extern int sysctl_doprof(int *, u_int, user_addr_t, size_t *,
88 user_addr_t, size_t newlen);
89 extern int sysctl_struct(user_addr_t, size_t *,
90 user_addr_t, size_t, void *, int);
91
92 lck_spin_t * mcount_lock;
93 lck_grp_t * mcount_lock_grp;
94 lck_attr_t * mcount_lock_attr;
95
96 /*
97 * Froms is actually a bunch of unsigned shorts indexing tos
98 */
99 struct gmonparam _gmonparam = { .state = GMON_PROF_OFF };
100
101 /*
102 * This code uses 32 bit mach object segment information from the currently
103 * running kernel.
104 */
105 void
106 kmstartup(void)
107 {
108 tostruct_t *cp;
109 kernel_segment_command_t *sgp; /* 32 bit mach object file segment */
110 struct gmonparam *p = &_gmonparam;
111
112 sgp = getsegbyname("__TEXT");
113 p->lowpc = (u_int32_t)sgp->vmaddr;
114 p->highpc = (u_int32_t)(sgp->vmaddr + sgp->vmsize);
115
116 /*
117 * Round lowpc and highpc to multiples of the density we're using
118 * so the rest of the scaling (here and in gprof) stays in ints.
119 */
120 p->lowpc = ROUNDDOWN(p->lowpc, HISTFRACTION * sizeof(HISTCOUNTER));
121 p->highpc = ROUNDUP(p->highpc, HISTFRACTION * sizeof(HISTCOUNTER));
122 p->textsize = p->highpc - p->lowpc;
123 printf("Profiling kernel, textsize=%lu [0x%016lx..0x%016lx]\n",
124 p->textsize, p->lowpc, p->highpc);
125 p->kcountsize = p->textsize / HISTFRACTION;
126 p->hashfraction = HASHFRACTION;
127 p->fromssize = p->textsize / HASHFRACTION;
128 p->tolimit = p->textsize * ARCDENSITY / 100;
129 if (p->tolimit < MINARCS)
130 p->tolimit = MINARCS;
131 else if (p->tolimit > MAXARCS)
132 p->tolimit = MAXARCS;
133 p->tossize = p->tolimit * sizeof(tostruct_t);
134 /* Why not use MALLOC with M_GPROF ? */
135 cp = (tostruct_t *)kalloc(p->kcountsize + p->fromssize + p->tossize);
136 if (cp == 0) {
137 printf("No memory for profiling.\n");
138 return;
139 }
140 bzero(cp, p->kcountsize + p->tossize + p->fromssize);
141 p->tos = cp;
142 cp = (tostruct_t *)((vm_offset_t)cp + p->tossize);
143 p->kcount = (u_short *)cp;
144 cp = (tostruct_t *)((vm_offset_t)cp + p->kcountsize);
145 p->froms = (u_short *)cp;
146
147 mcount_lock_grp = lck_grp_alloc_init("MCOUNT", LCK_GRP_ATTR_NULL);
148 mcount_lock_attr = lck_attr_alloc_init();
149 mcount_lock = lck_spin_alloc_init(mcount_lock_grp, mcount_lock_attr);
150
151 }
152
153 /*
154 * XXX These should be broken out into per-argument OID values,
155 * XXX since there are no sub-OID parameter values, but unfortunately
156 * XXX there is barely enough time for an initial conversion.
157 *
158 * Note: These items appear to be read/write.
159 */
160 STATIC int
161 sysctl_doprofhandle SYSCTL_HANDLER_ARGS
162 {
163 sysctl_doprof(int *name, u_int namelen, user_addr_t oldp, size_t *oldlenp,
164 user_addr_t newp, size_t newlen)
165 {
166 __unused int cmd = oidp->oid_arg2; /* subcommand*/
167 int *name = arg1; /* oid element argument vector */
168 int namelen = arg2; /* number of oid element arguments */
169 user_addr_t oldp = req->oldptr; /* user buffer copy out address */
170 size_t *oldlenp = req->oldlen; /* user buffer copy out size */
171 user_addr_t newp = req->newptr; /* user buffer copy in address */
172 size_t newlen = req->newlen; /* user buffer copy in size */
173
174 struct gmonparam *gp = &_gmonparam;
175 int error = 0;
176
177 /* all sysctl names at this level are terminal */
178 if (namelen != 1)
179 return (ENOTDIR); /* overloaded */
180
181 switch (name[0]) {
182 case GPROF_STATE:
183 error = sysctl_int(oldp, oldlenp, newp, newlen, &gp->state);
184 if (error)
185 break;
186 if (gp->state == GMON_PROF_OFF)
187 stopprofclock(kernproc);
188 else
189 startprofclock(kernproc);
190 break;
191 case GPROF_COUNT:
192 error = sysctl_struct(oldp, oldlenp, newp, newlen,
193 gp->kcount, gp->kcountsize);
194 break;
195 case GPROF_FROMS:
196 error = sysctl_struct(oldp, oldlenp, newp, newlen,
197 gp->froms, gp->fromssize);
198 break;
199 case GPROF_TOS:
200 error = sysctl_struct(oldp, oldlenp, newp, newlen,
201 gp->tos, gp->tossize);
202 break;
203 case GPROF_GMONPARAM:
204 error = sysctl_rdstruct(oldp, oldlenp, newp, gp, sizeof *gp);
205 break;
206 default:
207 error = ENOTSUP;
208 break;
209 }
210
211 /* adjust index so we return the right required/consumed amount */
212 if (!error)
213 req->oldidx += req->oldlen;
214
215 return(error);
216 }
217 SYSCTL_PROC(_kern, KERN_PROF, prof, STLFLAG_NODE|CTLFLAG_RW | CTLFLAG_LOCKED,
218 0, /* Pointer argument (arg1) */
219 0, /* Integer argument (arg2) */
220 sysctl_doprofhandle, /* Handler function */
221 NULL, /* No explicit data */
222 "");
223
224
225 /*
226 * mcount() called with interrupts disabled.
227 */
228 void
229 mcount(
230 uintptr_t frompc,
231 uintptr_t selfpc
232 )
233 {
234 unsigned short *frompcindex;
235 tostruct_t *top, *prevtop;
236 struct gmonparam *p = &_gmonparam;
237 long toindex;
238
239 /*
240 * check that we are profiling
241 * and that we aren't recursively invoked.
242 */
243 if (p->state != GMON_PROF_ON)
244 return;
245
246 lck_spin_lock(mcount_lock);
247
248 /*
249 * check that frompcindex is a reasonable pc value.
250 * for example: signal catchers get called from the stack,
251 * not from text space. too bad.
252 */
253 frompc -= p->lowpc;
254 if (frompc > p->textsize)
255 goto done;
256
257 frompcindex = &p->froms[frompc / (p->hashfraction * sizeof(*p->froms))];
258 toindex = *frompcindex;
259 if (toindex == 0) {
260 /*
261 * first time traversing this arc
262 */
263 toindex = ++p->tos[0].link;
264 if (toindex >= p->tolimit) {
265 /* halt further profiling */
266 goto overflow;
267 }
268 *frompcindex = toindex;
269 top = &p->tos[toindex];
270 top->selfpc = selfpc;
271 top->count = 1;
272 top->link = 0;
273 goto done;
274 }
275 top = &p->tos[toindex];
276 if (top->selfpc == selfpc) {
277 /*
278 * arc at front of chain; usual case.
279 */
280 top->count++;
281 goto done;
282 }
283 /*
284 * have to go looking down chain for it.
285 * top points to what we are looking at,
286 * prevtop points to previous top.
287 * we know it is not at the head of the chain.
288 */
289 for (; /* goto done */; ) {
290 if (top->link == 0) {
291 /*
292 * top is end of the chain and none of the chain
293 * had top->selfpc == selfpc.
294 * so we allocate a new tostruct
295 * and link it to the head of the chain.
296 */
297 toindex = ++p->tos[0].link;
298 if (toindex >= p->tolimit) {
299 goto overflow;
300 }
301 top = &p->tos[toindex];
302 top->selfpc = selfpc;
303 top->count = 1;
304 top->link = *frompcindex;
305 *frompcindex = toindex;
306 goto done;
307 }
308 /*
309 * otherwise, check the next arc on the chain.
310 */
311 prevtop = top;
312 top = &p->tos[top->link];
313 if (top->selfpc == selfpc) {
314 /*
315 * there it is.
316 * increment its count
317 * move it to the head of the chain.
318 */
319 top->count++;
320 toindex = prevtop->link;
321 prevtop->link = top->link;
322 top->link = *frompcindex;
323 *frompcindex = toindex;
324 goto done;
325 }
326
327 }
328 done:
329 lck_spin_unlock(mcount_lock);
330 return;
331
332 overflow:
333 p->state = GMON_PROF_ERROR;
334 lck_spin_unlock(mcount_lock);
335 printf("mcount: tos overflow\n");
336 return;
337 }
338
339 #endif /* GPROF */
340
341 #define PROFILE_LOCK(x)
342 #define PROFILE_UNLOCK(x)
343
344
345 /*
346 * Scale is a fixed-point number with the binary point 16 bits
347 * into the value, and is <= 1.0. pc is at most 32 bits, so the
348 * intermediate result is at most 48 bits.
349 */
350 //K64todo - this doesn't fit into 64 bit any more, it needs 64+16
351 #define PC_TO_INDEX(pc, prof) \
352 ((user_addr_t)(((u_quad_t)((pc) - (prof)->pr_off) * \
353 (u_quad_t)((prof)->pr_scale)) >> 16) & ~1)
354
355 /*
356 * Collect user-level profiling statistics; called on a profiling tick,
357 * when a process is running in user-mode. We use
358 * an AST that will vector us to trap() with a context in which copyin
359 * and copyout will work. Trap will then call addupc_task().
360 *
361 * Note that we may (rarely) not get around to the AST soon enough, and
362 * lose profile ticks when the next tick overwrites this one, but in this
363 * case the system is overloaded and the profile is probably already
364 * inaccurate.
365 *
366 * We can afford to take faults here. If the
367 * update fails, we simply turn off profiling.
368 */
369 void
370 addupc_task(struct proc *p, user_addr_t pc, u_int ticks)
371 {
372 user_addr_t off;
373 u_short count;
374
375 /* Testing P_PROFIL may be unnecessary, but is certainly safe. */
376 if ((p->p_flag & P_PROFIL) == 0 || ticks == 0)
377 return;
378
379 if (proc_is64bit(p)) {
380 struct user_uprof *prof;
381 user_addr_t cell;
382
383 for (prof = &p->p_stats->user_p_prof; prof; prof = prof->pr_next) {
384 off = PC_TO_INDEX(pc, prof);
385 cell = (prof->pr_base + off);
386 if (cell >= prof->pr_base &&
387 cell < (prof->pr_size + prof->pr_base)) {
388 if (copyin(cell, (caddr_t) &count, sizeof(count)) == 0) {
389 count += ticks;
390 if(copyout((caddr_t) &count, cell, sizeof(count)) == 0)
391 return;
392 }
393 p->p_stats->user_p_prof.pr_scale = 0;
394 stopprofclock(p);
395 break;
396 }
397 }
398 }
399 else {
400 struct uprof *prof;
401 short *cell;
402
403 for (prof = &p->p_stats->p_prof; prof; prof = prof->pr_next) {
404 off = PC_TO_INDEX(pc,prof);
405 cell = (short *)(prof->pr_base + off);
406 if (cell >= (short *)prof->pr_base &&
407 cell < (short*)(prof->pr_size + prof->pr_base)) {
408 if (copyin(CAST_USER_ADDR_T(cell), (caddr_t) &count, sizeof(count)) == 0) {
409 count += ticks;
410 if(copyout((caddr_t) &count, CAST_USER_ADDR_T(cell), sizeof(count)) == 0)
411 return;
412 }
413 p->p_stats->p_prof.pr_scale = 0;
414 stopprofclock(p);
415 break;
416 }
417 }
418 }
419 }