1/*-
2 * Copyright (c) 2015 Ruslan Bukin <br@bsdpad.com>
3 * All rights reserved.
4 *
5 * This software was developed by the University of Cambridge Computer
6 * Laboratory with support from ARM Ltd.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD$");
32
33#include <sys/param.h>
34#include <sys/pmc.h>
35#include <sys/proc.h>
36#include <sys/systm.h>
37
38#include <machine/cpu.h>
39#include <machine/md_var.h>
40#include <machine/pmc_mdep.h>
41#include <machine/stack.h>
42
43#include <vm/vm.h>
44#include <vm/vm_param.h>
45#include <vm/pmap.h>
46
47struct pmc_mdep *
48pmc_md_initialize()
49{
50
51	return (pmc_arm64_initialize());
52}
53
54void
55pmc_md_finalize(struct pmc_mdep *md)
56{
57
58	pmc_arm64_finalize(md);
59}
60
61int
62pmc_save_kernel_callchain(uintptr_t *cc, int maxsamples,
63    struct trapframe *tf)
64{
65	uintptr_t pc, r, stackstart, stackend, fp;
66	struct thread *td;
67	int count;
68
69	KASSERT(TRAPF_USERMODE(tf) == 0,("[arm,%d] not a kernel backtrace",
70	    __LINE__));
71
72	td = curthread;
73	pc = PMC_TRAPFRAME_TO_PC(tf);
74	*cc++ = pc;
75
76	if (maxsamples <= 1)
77		return (1);
78
79	stackstart = (uintptr_t) td->td_kstack;
80	stackend = (uintptr_t) td->td_kstack + td->td_kstack_pages * PAGE_SIZE;
81	fp = PMC_TRAPFRAME_TO_FP(tf);
82
83	if (!PMC_IN_KERNEL(pc) ||
84	    !PMC_IN_KERNEL_STACK(fp, stackstart, stackend))
85		return (1);
86
87	for (count = 1; count < maxsamples; count++) {
88		/* Use saved lr as pc. */
89		r = fp + sizeof(uintptr_t);
90		if (!PMC_IN_KERNEL_STACK(r, stackstart, stackend))
91			break;
92		pc = *(uintptr_t *)r;
93		if (!PMC_IN_KERNEL(pc))
94			break;
95
96		*cc++ = pc;
97
98		/* Switch to next frame up */
99		r = fp;
100		if (!PMC_IN_KERNEL_STACK(r, stackstart, stackend))
101			break;
102		fp = *(uintptr_t *)r;
103		if (!PMC_IN_KERNEL_STACK(fp, stackstart, stackend))
104			break;
105	}
106
107	return (count);
108}
109
110int
111pmc_save_user_callchain(uintptr_t *cc, int maxsamples,
112    struct trapframe *tf)
113{
114	uintptr_t pc, r, oldfp, fp;
115	struct thread *td;
116	int count;
117
118	KASSERT(TRAPF_USERMODE(tf), ("[x86,%d] Not a user trap frame tf=%p",
119	    __LINE__, (void *) tf));
120
121	td = curthread;
122	pc = PMC_TRAPFRAME_TO_PC(tf);
123	*cc++ = pc;
124
125	if (maxsamples <= 1)
126		return (1);
127
128	oldfp = fp = PMC_TRAPFRAME_TO_FP(tf);
129
130	if (!PMC_IN_USERSPACE(pc) ||
131	    !PMC_IN_USERSPACE(fp))
132		return (1);
133
134	for (count = 1; count < maxsamples; count++) {
135		/* Use saved lr as pc. */
136		r = fp + sizeof(uintptr_t);
137		if (copyin((void *)r, &pc, sizeof(pc)) != 0)
138			break;
139		if (!PMC_IN_USERSPACE(pc))
140			break;
141
142		*cc++ = pc;
143
144		/* Switch to next frame up */
145		oldfp = fp;
146		r = fp;
147		if (copyin((void *)r, &fp, sizeof(fp)) != 0)
148			break;
149		if (fp < oldfp || !PMC_IN_USERSPACE(fp))
150			break;
151	}
152
153	return (count);
154}
155