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/spl.h>
74#include <machine/machine_routines.h>
75
76#include <sys/mount_internal.h>
77#include <sys/sysproto.h>
78
79#include <mach/mach_types.h>
80#include <kern/kern_types.h>
81#include <kern/cpu_number.h>
82#include <kern/kalloc.h>
83
84#ifdef GPROF
85#include <sys/malloc.h>
86#include <sys/gmon.h>
87
88extern int sysctl_doprof(int *, u_int, user_addr_t, size_t *,
89		user_addr_t, size_t newlen);
90extern int sysctl_struct(user_addr_t, size_t *,
91		user_addr_t, size_t, void *, int);
92
93lck_spin_t * mcount_lock;
94lck_grp_t * mcount_lock_grp;
95lck_attr_t * mcount_lock_attr;
96
97/*
98 * Froms is actually a bunch of unsigned shorts indexing tos
99 */
100struct gmonparam _gmonparam = { .state = GMON_PROF_OFF };
101
102/*
103 * This code uses 32 bit mach object segment information from the currently
104 * running kernel.
105 */
106void
107kmstartup(void)
108{
109	tostruct_t *cp;
110	kernel_segment_command_t	*sgp;	/* 32 bit mach object file segment */
111	struct gmonparam *p = &_gmonparam;
112
113	sgp = getsegbyname("__TEXT");
114	p->lowpc = (u_int32_t)sgp->vmaddr;
115	p->highpc = (u_int32_t)(sgp->vmaddr + sgp->vmsize);
116
117	/*
118	 * Round lowpc and highpc to multiples of the density we're using
119	 * so the rest of the scaling (here and in gprof) stays in ints.
120	 */
121	p->lowpc = ROUNDDOWN(p->lowpc, HISTFRACTION * sizeof(HISTCOUNTER));
122	p->highpc = ROUNDUP(p->highpc, HISTFRACTION * sizeof(HISTCOUNTER));
123	p->textsize = p->highpc - p->lowpc;
124	printf("Profiling kernel, textsize=%lu [0x%016lx..0x%016lx]\n",
125	       p->textsize, p->lowpc, p->highpc);
126	p->kcountsize = p->textsize / HISTFRACTION;
127	p->hashfraction = HASHFRACTION;
128	p->fromssize = p->textsize / HASHFRACTION;
129	p->tolimit = p->textsize * ARCDENSITY / 100;
130	if (p->tolimit < MINARCS)
131		p->tolimit = MINARCS;
132	else if (p->tolimit > MAXARCS)
133		p->tolimit = MAXARCS;
134	p->tossize = p->tolimit * sizeof(tostruct_t);
135	/* Why not use MALLOC with M_GPROF ? */
136	cp = (tostruct_t *)kalloc(p->kcountsize + p->fromssize + p->tossize);
137	if (cp == 0) {
138		printf("No memory for profiling.\n");
139		return;
140	}
141	bzero(cp, p->kcountsize + p->tossize + p->fromssize);
142	p->tos = cp;
143	cp = (tostruct_t *)((vm_offset_t)cp + p->tossize);
144	p->kcount = (u_short *)cp;
145	cp = (tostruct_t *)((vm_offset_t)cp + p->kcountsize);
146	p->froms = (u_short *)cp;
147
148	mcount_lock_grp = lck_grp_alloc_init("MCOUNT", LCK_GRP_ATTR_NULL);
149	mcount_lock_attr = lck_attr_alloc_init();
150	mcount_lock = lck_spin_alloc_init(mcount_lock_grp, mcount_lock_attr);
151
152}
153
154/*
155 * XXX		These should be broken out into per-argument OID values,
156 * XXX		since there are no sub-OID parameter values, but unfortunately
157 * XXX		there is barely enough time for an initial conversion.
158 *
159 * Note:	These items appear to be read/write.
160 */
161STATIC int
162sysctl_doprofhandle SYSCTL_HANDLER_ARGS
163{
164sysctl_doprof(int *name, u_int namelen, user_addr_t oldp, size_t *oldlenp,
165              user_addr_t newp, size_t newlen)
166{
167	__unused int cmd = oidp->oid_arg2;	/* subcommand*/
168	int *name = arg1;		/* oid element argument vector */
169	int namelen = arg2;		/* number of oid element arguments */
170	user_addr_t oldp = req->oldptr;	/* user buffer copy out address */
171	size_t *oldlenp = req->oldlen;	/* user buffer copy out size */
172	user_addr_t newp = req->newptr;	/* user buffer copy in address */
173	size_t newlen = req->newlen;	/* user buffer copy in size */
174
175	struct gmonparam *gp = &_gmonparam;
176	int error = 0;
177
178	/* all sysctl names at this level are terminal */
179	if (namelen != 1)
180		return (ENOTDIR);		/* overloaded */
181
182	switch (name[0]) {
183	case GPROF_STATE:
184		error = sysctl_int(oldp, oldlenp, newp, newlen, &gp->state);
185		if (error)
186			break;
187		if (gp->state == GMON_PROF_OFF)
188			stopprofclock(kernproc);
189		else
190			startprofclock(kernproc);
191		break;
192	case GPROF_COUNT:
193		error = sysctl_struct(oldp, oldlenp, newp, newlen,
194		                      gp->kcount, gp->kcountsize);
195		break;
196	case GPROF_FROMS:
197		error = sysctl_struct(oldp, oldlenp, newp, newlen,
198		                      gp->froms, gp->fromssize);
199		break;
200	case GPROF_TOS:
201		error = sysctl_struct(oldp, oldlenp, newp, newlen,
202		                      gp->tos, gp->tossize);
203		break;
204	case GPROF_GMONPARAM:
205		error = sysctl_rdstruct(oldp, oldlenp, newp, gp, sizeof *gp);
206		break;
207	default:
208		error = ENOTSUP;
209		break;
210	}
211
212	/* adjust index so we return the right required/consumed amount */
213	if (!error)
214		req->oldidx += req->oldlen;
215
216	return(error);
217}
218SYSCTL_PROC(_kern, KERN_PROF, prof, STLFLAG_NODE|CTLFLAG_RW | CTLFLAG_LOCKED,
219	0,			/* Pointer argument (arg1) */
220	0,			/* Integer argument (arg2) */
221	sysctl_doprofhandle,	/* Handler function */
222	NULL,			/* No explicit data */
223	"");
224
225
226/*
227 * mcount() called with interrupts disabled.
228 */
229void
230mcount(
231    uintptr_t frompc,
232    uintptr_t selfpc
233)
234{
235    unsigned short *frompcindex;
236	tostruct_t *top, *prevtop;
237	struct gmonparam *p = &_gmonparam;
238	long toindex;
239
240    /*
241     * check that we are profiling
242     * and that we aren't recursively invoked.
243     */
244    if (p->state != GMON_PROF_ON)
245        return;
246
247	lck_spin_lock(mcount_lock);
248
249	/*
250	 *	check that frompcindex is a reasonable pc value.
251	 *	for example:	signal catchers get called from the stack,
252	 *			not from text space.  too bad.
253	 */
254	frompc -= p->lowpc;
255	if (frompc > p->textsize)
256		goto done;
257
258	frompcindex = &p->froms[frompc / (p->hashfraction * sizeof(*p->froms))];
259	toindex = *frompcindex;
260	if (toindex == 0) {
261		/*
262		 *	first time traversing this arc
263		 */
264		toindex = ++p->tos[0].link;
265		if (toindex >= p->tolimit) {
266            /* halt further profiling */
267			goto overflow;
268		}
269		*frompcindex = toindex;
270		top = &p->tos[toindex];
271		top->selfpc = selfpc;
272		top->count = 1;
273		top->link = 0;
274		goto done;
275	}
276	top = &p->tos[toindex];
277	if (top->selfpc == selfpc) {
278		/*
279		 *	arc at front of chain; usual case.
280		 */
281		top->count++;
282		goto done;
283	}
284	/*
285	 *	have to go looking down chain for it.
286	 *	top points to what we are looking at,
287	 *	prevtop points to previous top.
288	 *	we know it is not at the head of the chain.
289	 */
290	for (; /* goto done */; ) {
291		if (top->link == 0) {
292			/*
293			 *	top is end of the chain and none of the chain
294			 *	had top->selfpc == selfpc.
295			 *	so we allocate a new tostruct
296			 *	and link it to the head of the chain.
297			 */
298			toindex = ++p->tos[0].link;
299			if (toindex >= p->tolimit) {
300				goto overflow;
301			}
302			top = &p->tos[toindex];
303			top->selfpc = selfpc;
304			top->count = 1;
305			top->link = *frompcindex;
306			*frompcindex = toindex;
307			goto done;
308		}
309		/*
310		 *	otherwise, check the next arc on the chain.
311		 */
312		prevtop = top;
313		top = &p->tos[top->link];
314		if (top->selfpc == selfpc) {
315			/*
316			 *	there it is.
317			 *	increment its count
318			 *	move it to the head of the chain.
319			 */
320			top->count++;
321			toindex = prevtop->link;
322			prevtop->link = top->link;
323			top->link = *frompcindex;
324			*frompcindex = toindex;
325			goto done;
326		}
327
328	}
329done:
330	lck_spin_unlock(mcount_lock);
331	return;
332
333overflow:
334    p->state = GMON_PROF_ERROR;
335        lck_spin_unlock(mcount_lock);
336	printf("mcount: tos overflow\n");
337	return;
338}
339
340#endif /* GPROF */
341
342#define PROFILE_LOCK(x)
343#define PROFILE_UNLOCK(x)
344
345
346/*
347 * Scale is a fixed-point number with the binary point 16 bits
348 * into the value, and is <= 1.0.  pc is at most 32 bits, so the
349 * intermediate result is at most 48 bits.
350 */
351//K64todo - this doesn't fit into 64 bit any more, it needs 64+16
352#define PC_TO_INDEX(pc, prof) \
353	((user_addr_t)(((u_quad_t)((pc) - (prof)->pr_off) * \
354			(u_quad_t)((prof)->pr_scale)) >> 16) & ~1)
355
356/*
357 * Collect user-level profiling statistics; called on a profiling tick,
358 * when a process is running in user-mode. We use
359 * an AST that will vector us to trap() with a context in which copyin
360 * and copyout will work.  Trap will then call addupc_task().
361 *
362 * Note that we may (rarely) not get around to the AST soon enough, and
363 * lose profile ticks when the next tick overwrites this one, but in this
364 * case the system is overloaded and the profile is probably already
365 * inaccurate.
366 *
367 * We can afford to take faults here.  If the
368 * update fails, we simply turn off profiling.
369 */
370void
371addupc_task(struct proc *p, user_addr_t pc, u_int ticks)
372{
373	user_addr_t off;
374	u_short count;
375
376	/* Testing P_PROFIL may be unnecessary, but is certainly safe. */
377	if ((p->p_flag & P_PROFIL) == 0 || ticks == 0)
378		return;
379
380	if (proc_is64bit(p)) {
381        struct user_uprof *prof;
382        user_addr_t cell;
383
384        for (prof = &p->p_stats->user_p_prof; prof; prof = prof->pr_next) {
385            off = PC_TO_INDEX(pc, prof);
386            cell = (prof->pr_base + off);
387            if (cell >= prof->pr_base &&
388                cell < (prof->pr_size + prof->pr_base)) {
389                if (copyin(cell, (caddr_t) &count, sizeof(count)) == 0) {
390                    count += ticks;
391                    if(copyout((caddr_t) &count, cell, sizeof(count)) == 0)
392                        return;
393                }
394                p->p_stats->user_p_prof.pr_scale = 0;
395                stopprofclock(p);
396                break;
397            }
398        }
399	}
400	else {
401        struct uprof *prof;
402        short *cell;
403
404        for (prof = &p->p_stats->p_prof; prof; prof = prof->pr_next) {
405            off = PC_TO_INDEX(pc,prof);
406            cell = (short *)(prof->pr_base + off);
407            if (cell >= (short *)prof->pr_base &&
408                cell < (short*)(prof->pr_size + prof->pr_base)) {
409                if (copyin(CAST_USER_ADDR_T(cell), (caddr_t) &count, sizeof(count)) == 0) {
410                    count += ticks;
411                    if(copyout((caddr_t) &count, CAST_USER_ADDR_T(cell), sizeof(count)) == 0)
412                        return;
413                }
414                p->p_stats->p_prof.pr_scale = 0;
415                stopprofclock(p);
416                break;
417            }
418        }
419	}
420}
421