1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
|
/*
* Mach Operating System
* Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie Mellon
* the rights to redistribute these changes.
*/
/*
* xpr silent tracing circular buffer.
*/
#include <string.h>
#include <kern/debug.h>
#include <kern/xpr.h>
#include <kern/lock.h>
#include "cpu_number.h"
#include <machine/machspl.h>
#include <vm/vm_kern.h>
/*
* After a spontaneous reboot, it is desirable to look
* at the old xpr buffer. Assuming xprbootstrap allocates
* the buffer in the same place in physical memory and
* the reboot doesn't clear memory, this should work.
* xprptr will be reset, but the saved value should be OK.
* Just set xprenable false so the buffer isn't overwritten.
*/
decl_simple_lock_data(, xprlock)
boolean_t xprenable = TRUE; /* Enable xpr tracing */
int nxprbufs = 0; /* Number of contiguous xprbufs allocated */
int xprflags = 0; /* Bit mask of xpr flags enabled */
struct xprbuf *xprbase; /* Pointer to circular buffer nxprbufs*sizeof(xprbuf)*/
struct xprbuf *xprptr; /* Currently allocated xprbuf */
struct xprbuf *xprlast; /* Pointer to end of circular buffer */
/*VARARGS1*/
void xpr(msg, arg1, arg2, arg3, arg4, arg5)
char *msg;
int arg1, arg2, arg3, arg4, arg5;
{
spl_t s;
struct xprbuf *x;
/* If we aren't initialized, ignore trace request */
if (!xprenable || (xprptr == 0))
return;
/* Guard against all interrupts and allocate next buffer. */
s = splhigh();
simple_lock(&xprlock);
x = xprptr++;
if (xprptr >= xprlast) {
/* wrap around */
xprptr = xprbase;
}
/* Save xprptr in allocated memory. */
*(struct xprbuf **)xprlast = xprptr;
simple_unlock(&xprlock);
splx(s);
x->msg = msg;
x->arg1 = arg1;
x->arg2 = arg2;
x->arg3 = arg3;
x->arg4 = arg4;
x->arg5 = arg5;
x->timestamp = XPR_TIMESTAMP;
x->cpuinfo = cpu_number();
}
void xprbootstrap(void)
{
vm_offset_t addr;
vm_size_t size;
kern_return_t kr;
simple_lock_init(&xprlock);
if (nxprbufs == 0)
return; /* assume XPR support not desired */
/* leave room at the end for a saved copy of xprptr */
size = nxprbufs * sizeof(struct xprbuf) + sizeof xprptr;
kr = kmem_alloc_wired(kernel_map, &addr, size);
if (kr != KERN_SUCCESS)
panic("xprbootstrap");
if (xprenable) {
/*
* If xprenable is set (the default) then we zero
* the buffer so xpr_dump doesn't encounter bad pointers.
* If xprenable isn't set, then we preserve
* the original contents of the buffer. This is useful
* if memory survives reboots, so xpr_dump can show
* the previous buffer contents.
*/
memset((char *) addr, 0, size);
}
xprbase = (struct xprbuf *) addr;
xprlast = &xprbase[nxprbufs];
xprptr = xprbase; /* setting xprptr enables tracing */
}
int xprinitial = 0;
void xprinit(void)
{
xprflags |= xprinitial;
}
#if MACH_KDB
#include <machine/setjmp.h>
extern void db_printf();
extern jmp_buf_t *db_recover;
/*
* Print current content of xpr buffers (KDB's sake)
* Use stack order to make it understandable.
*
* Called as "!xpr_dump" this dumps the kernel's xpr buffer.
* Called with arguments, it can dump xpr buffers in user tasks,
* assuming they use the same format as the kernel.
*/
void xpr_dump(base, nbufs)
struct xprbuf *base;
int nbufs;
{
jmp_buf_t db_jmpbuf;
jmp_buf_t *prev;
struct xprbuf *last, *ptr;
struct xprbuf *x;
int i;
spl_t s = s;
if (base == 0) {
base = xprbase;
nbufs = nxprbufs;
}
if (nbufs == 0)
return;
if (base == xprbase) {
s = splhigh();
simple_lock(&xprlock);
}
last = base + nbufs;
ptr = * (struct xprbuf **) last;
prev = db_recover;
if (_setjmp(db_recover = &db_jmpbuf) == 0)
for (x = ptr, i = 0; i < nbufs; i++) {
if (--x < base)
x = last - 1;
if (x->msg == 0)
break;
db_printf("<%d:%x:%x> ", x - base, x->cpuinfo, x->timestamp);
db_printf(x->msg, x->arg1,x->arg2,x->arg3,x->arg4,x->arg5);
}
db_recover = prev;
if (base == xprbase) {
simple_unlock(&xprlock);
(void) splx(s);
}
}
#endif /* MACH_KDB */
|
