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
|
/////////////////////////////////////////////////////////////////////////
// $Id: slowdown_timer.cc,v 1.25 2006/05/27 15:54:49 sshwarts Exp $
/////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2002 MandrakeSoft S.A.
//
// MandrakeSoft S.A.
// 43, rue d'Aboukir
// 75002 Paris - France
// http://www.linux-mandrake.com/
// http://www.mandrakesoft.com/
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
//
#include "bochs.h"
#include "slowdown_timer.h"
#include <errno.h>
//These need to stay printfs because they are useless in the log file.
#define BX_SLOWDOWN_PRINTF_FEEDBACK 0
#define SECINUSEC 1000000
#define usectosec(a) ((a)/SECINUSEC)
#define sectousec(a) ((a)*SECINUSEC)
#define nsectousec(a) ((a)/1000)
#define MSECINUSEC 1000
#define usectomsec(a) ((a)/MSECINUSEC)
#define Qval 1000
#define MAXMULT 1.5
#define REALTIME_Q SECINUSEC
#define LOG_THIS bx_slowdown_timer.
bx_slowdown_timer_c bx_slowdown_timer;
bx_slowdown_timer_c::bx_slowdown_timer_c()
{
put("STIMER");
settype(STIMERLOG);
s.start_time=0;
s.start_emulated_time=0;
s.timer_handle=BX_NULL_TIMER_HANDLE;
}
void bx_slowdown_timer_c::init(void)
{
// Return early if slowdown timer not selected
if ((SIM->get_param_enum(BXPN_CLOCK_SYNC)->get() != BX_CLOCK_SYNC_SLOWDOWN) &&
(SIM->get_param_enum(BXPN_CLOCK_SYNC)->get() != BX_CLOCK_SYNC_BOTH) )
return;
BX_INFO(("using 'slowdown' timer synchronization method"));
s.MAXmultiplier=MAXMULT;
s.Q=Qval;
if(s.MAXmultiplier<1)
s.MAXmultiplier=1;
s.start_time=sectousec(time(NULL));
s.start_emulated_time = bx_pc_system.time_usec();
s.lasttime=0;
if (s.timer_handle == BX_NULL_TIMER_HANDLE) {
s.timer_handle=bx_pc_system.register_timer(this, timer_handler, 100 , 1, 1,
"slowdown_timer");
}
bx_pc_system.deactivate_timer(s.timer_handle);
bx_pc_system.activate_timer(s.timer_handle,(Bit32u)s.Q,0);
}
#if BX_SUPPORT_SAVE_RESTORE
void bx_slowdown_timer_c::after_restore_state(void)
{
s.start_emulated_time = bx_pc_system.time_usec();
}
#endif
void bx_slowdown_timer_c::timer_handler(void * this_ptr)
{
bx_slowdown_timer_c * class_ptr = (bx_slowdown_timer_c *) this_ptr;
class_ptr->handle_timer();
}
void bx_slowdown_timer_c::handle_timer()
{
Bit64u total_emu_time = (bx_pc_system.time_usec()) - s.start_emulated_time;
Bit64u wanttime = s.lasttime+s.Q;
Bit64u totaltime = sectousec(time(NULL)) - s.start_time;
Bit64u thistime=(wanttime>totaltime)?wanttime:totaltime;
#if BX_SLOWDOWN_PRINTF_FEEDBACK
printf("Entering slowdown timer handler.\n");
#endif
/* Decide if we're behind.
* Set interrupt interval accordingly. */
if(totaltime > total_emu_time) {
bx_pc_system.deactivate_timer(s.timer_handle);
bx_pc_system.activate_timer(s.timer_handle,
(Bit32u)(s.MAXmultiplier * (float)((Bit64s)s.Q)), 0);
#if BX_SLOWDOWN_PRINTF_FEEDBACK
printf("running at MAX speed\n");
#endif
} else {
bx_pc_system.deactivate_timer(s.timer_handle);
bx_pc_system.activate_timer(s.timer_handle,(Bit32u)s.Q,0);
#if BX_SLOWDOWN_PRINTF_FEEDBACK
printf("running at NORMAL speed\n");
#endif
}
/* Make sure we took at least one time quantum. */
/* This is a little strange. I'll try to explain.
* We're running bochs one second ahead of real time.
* this gives us a very precise division on whether
* we're ahead or behind the second line.
* Basically, here's how it works:
* *****|******************|***********...
* Time Time+1sec
* <^Bochs doesn't delay.
* ^>Bochs delays.
* <^Bochs runs at MAX speed.
* ^>Bochs runs at normal
*/
if(wanttime > (totaltime+REALTIME_Q)) {
#if BX_HAVE_USLEEP
usleep(s.Q);
#elif BX_HAVE_MSLEEP
msleep(usectomsec((Bit32u)s.Q));
#elif BX_HAVE_SLEEP
sleep(usectosec(s.Q));
#else
#error do not know have to sleep
#endif //delay(wanttime-totaltime);
/* alternatively: delay(Q);
* This works okay because we share the delay between
* two time quantums.
*/
#if BX_SLOWDOWN_PRINTF_FEEDBACK
printf("DELAYING for a quantum\n");
#endif
}
s.lasttime=thistime;
//Diagnostic info:
#if 0
if(wanttime > (totaltime+REALTIME_Q)) {
if(totaltime > total_emu_time) {
printf("Solving OpenBSD problem.\n");
} else {
printf("too fast.\n");
}
} else {
if(totaltime > total_emu_time) {
printf("too slow.\n");
} else {
printf("sometimes invalid state, normally okay.\n");
}
}
#endif // Diagnostic info
}
|
