blob: ae01e0b05d24695217f5fa981b4084842dadca9e [file] [log] [blame]
wdenk85ec0bc2003-03-31 16:34:49 +00001/*
2 * This program is free software; you can redistribute it and/or
3 * modify it under the terms of the GNU General Public License as
4 * published by the Free Software Foundation; either version 2 of
5 * the License, or (at your option) any later version.
wdenk3e386912003-04-05 00:53:31 +00006 *
wdenk85ec0bc2003-03-31 16:34:49 +00007 * This program is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 * GNU General Public License for more details.
wdenk3e386912003-04-05 00:53:31 +000011 *
wdenk85ec0bc2003-03-31 16:34:49 +000012 * You should have received a copy of the GNU General Public License
13 * along with this program; if not, write to the Free Software
14 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
15 * MA 02111-1307 USA
16 */
17
18#include <common.h>
wdenk27b207f2003-07-24 23:38:38 +000019#include <exports.h>
wdenk85ec0bc2003-03-31 16:34:49 +000020
21/*
22 * Author: Arun Dharankar <ADharankar@ATTBI.Com>
23 *
24 * A very simple thread/schedular model:
25 * - only one master thread, and no parent child relation maintained
26 * - parent thread cannot be stopped or deleted
27 * - no permissions or credentials
28 * - no elaborate safety checks
29 * - cooperative multi threading
30 * - Simple round-robin scheduleing with no priorities
31 * - no metering/statistics collection
32 *
33 * Basic idea of implementing this is to allow more than one tests to
34 * execute "simultaneously".
35 *
36 * This may be modified such thread_yield may be called in syscalls, and
37 * timer interrupts.
38 */
39
40
41#define MAX_THREADS 8
42
43#define CTX_SIZE 512
44#define STK_SIZE 8*1024
45
46#define STATE_EMPTY 0
47#define STATE_RUNNABLE 1
48#define STATE_STOPPED 2
49#define STATE_TERMINATED 2
50
51#define MASTER_THREAD 0
52
53#define RC_FAILURE (-1)
54#define RC_SUCCESS (0)
55
wdenk3e386912003-04-05 00:53:31 +000056typedef vu_char *jmp_ctx;
57unsigned long setctxsp (vu_char *sp);
58int ppc_setjmp(jmp_ctx env);
59void ppc_longjmp(jmp_ctx env, int val);
60#define setjmp ppc_setjmp
61#define longjmp ppc_longjmp
62
wdenk85ec0bc2003-03-31 16:34:49 +000063struct lthread {
64 int state;
65 int retval;
66 char stack[STK_SIZE];
67 uchar context[CTX_SIZE];
68 int (*func) (void *);
69 void *arg;
70};
71static volatile struct lthread lthreads[MAX_THREADS];
72static volatile int current_tid = MASTER_THREAD;
73
74
75static uchar dbg = 0;
76
wdenk3e386912003-04-05 00:53:31 +000077#define PDEBUG(fmt, args...) { \
78 if(dbg != 0) { \
wdenk27b207f2003-07-24 23:38:38 +000079 printf("[%s %d %s]: ",__FILE__,__LINE__,__FUNCTION__);\
80 printf(fmt, ##args); \
81 printf("\n"); \
wdenk3e386912003-04-05 00:53:31 +000082 } \
83}
wdenk85ec0bc2003-03-31 16:34:49 +000084
85static int testthread (void *);
86static void sched_init (void);
87static int thread_create (int (*func) (void *), void *arg);
88static int thread_start (int id);
89static void thread_yield (void);
90static int thread_delete (int id);
91static int thread_join (int *ret);
wdenk3e386912003-04-05 00:53:31 +000092
93#if 0 /* not used yet */
wdenk85ec0bc2003-03-31 16:34:49 +000094static int thread_stop (int id);
wdenk3e386912003-04-05 00:53:31 +000095#endif /* not used yet */
wdenk85ec0bc2003-03-31 16:34:49 +000096
97/* An example of schedular test */
98
99#define NUMTHREADS 7
wdenk27b207f2003-07-24 23:38:38 +0000100int sched (int ac, char *av[])
wdenk85ec0bc2003-03-31 16:34:49 +0000101{
102 int i, j;
103 int tid[NUMTHREADS];
104 int names[NUMTHREADS];
105
wdenk27b207f2003-07-24 23:38:38 +0000106 app_startup(av);
107
wdenk85ec0bc2003-03-31 16:34:49 +0000108 sched_init ();
109
110 for (i = 0; i < NUMTHREADS; i++) {
111 names[i] = i;
112 j = thread_create (testthread, (void *) &names[i]);
113 if (j == RC_FAILURE)
wdenk27b207f2003-07-24 23:38:38 +0000114 printf ("schedtest: Failed to create thread %d\n", i);
wdenk85ec0bc2003-03-31 16:34:49 +0000115 if (j > 0) {
wdenk27b207f2003-07-24 23:38:38 +0000116 printf ("schedtest: Created thread with id %d, name %d\n",
wdenk3e386912003-04-05 00:53:31 +0000117 j, i);
wdenk85ec0bc2003-03-31 16:34:49 +0000118 tid[i] = j;
119 }
120 }
wdenk27b207f2003-07-24 23:38:38 +0000121 printf ("schedtest: Threads created\n");
wdenk85ec0bc2003-03-31 16:34:49 +0000122
wdenk27b207f2003-07-24 23:38:38 +0000123 printf ("sched_test: function=0x%08x\n", (unsigned)testthread);
wdenk85ec0bc2003-03-31 16:34:49 +0000124 for (i = 0; i < NUMTHREADS; i++) {
wdenk27b207f2003-07-24 23:38:38 +0000125 printf ("schedtest: Setting thread %d runnable\n", tid[i]);
wdenk85ec0bc2003-03-31 16:34:49 +0000126 thread_start (tid[i]);
127 thread_yield ();
128 }
wdenk27b207f2003-07-24 23:38:38 +0000129 printf ("schedtest: Started %d threads\n", NUMTHREADS);
wdenk85ec0bc2003-03-31 16:34:49 +0000130
131 while (1) {
wdenk27b207f2003-07-24 23:38:38 +0000132 printf ("schedtest: Waiting for threads to complete\n");
133 if (tstc () && getc () == 0x3) {
134 printf ("schedtest: Aborting threads...\n");
wdenk85ec0bc2003-03-31 16:34:49 +0000135 for (i = 0; i < NUMTHREADS; i++) {
wdenk27b207f2003-07-24 23:38:38 +0000136 printf ("schedtest: Deleting thread %d\n", tid[i]);
wdenk85ec0bc2003-03-31 16:34:49 +0000137 thread_delete (tid[i]);
138 }
139 return RC_SUCCESS;
140 }
141 j = -1;
142 i = thread_join (&j);
143 if (i == RC_FAILURE) {
wdenk27b207f2003-07-24 23:38:38 +0000144 printf ("schedtest: No threads pending, "
wdenk3e386912003-04-05 00:53:31 +0000145 "exiting schedular test\n");
wdenk85ec0bc2003-03-31 16:34:49 +0000146 return RC_SUCCESS;
147 }
wdenk27b207f2003-07-24 23:38:38 +0000148 printf ("schedtest: thread is %d returned %d\n", i, j);
wdenk85ec0bc2003-03-31 16:34:49 +0000149 thread_yield ();
150 }
151
152 return RC_SUCCESS;
153}
154
155static int testthread (void *name)
156{
157 int i;
158
wdenk27b207f2003-07-24 23:38:38 +0000159 printf ("testthread: Begin executing thread, myname %d, &i=0x%08x\n",
160 *(int *) name, (unsigned)&i);
wdenk85ec0bc2003-03-31 16:34:49 +0000161
wdenk27b207f2003-07-24 23:38:38 +0000162 printf ("Thread %02d, i=%d\n", *(int *) name, i);
wdenk85ec0bc2003-03-31 16:34:49 +0000163
164 for (i = 0; i < 0xffff * (*(int *) name + 1); i++) {
wdenk27b207f2003-07-24 23:38:38 +0000165 if (tstc () && getc () == 0x3) {
166 printf ("testthread: myname %d terminating.\n",
wdenk3e386912003-04-05 00:53:31 +0000167 *(int *) name);
wdenk85ec0bc2003-03-31 16:34:49 +0000168 return *(int *) name + 1;
169 }
170
171 if (i % 100 == 0)
172 thread_yield ();
173 }
174
wdenk27b207f2003-07-24 23:38:38 +0000175 printf ("testthread: returning %d, i=0x%x\n",
wdenk3e386912003-04-05 00:53:31 +0000176 *(int *) name + 1, i);
wdenk85ec0bc2003-03-31 16:34:49 +0000177
178 return *(int *) name + 1;
179}
180
181
182static void sched_init (void)
183{
184 int i;
185
186 for (i = MASTER_THREAD + 1; i < MAX_THREADS; i++)
187 lthreads[i].state = STATE_EMPTY;
188
189 current_tid = MASTER_THREAD;
190 lthreads[current_tid].state = STATE_RUNNABLE;
wdenk3e386912003-04-05 00:53:31 +0000191 PDEBUG ("sched_init: master context = 0x%08x",
wdenk27b207f2003-07-24 23:38:38 +0000192 (unsigned)lthreads[current_tid].context);
wdenk85ec0bc2003-03-31 16:34:49 +0000193 return;
194}
195
196static void thread_yield (void)
197{
198 static int i;
199
wdenk3e386912003-04-05 00:53:31 +0000200 PDEBUG ("thread_yield: current tid=%d", current_tid);
wdenk85ec0bc2003-03-31 16:34:49 +0000201
202#define SWITCH(new) \
203 if(lthreads[new].state == STATE_RUNNABLE) { \
wdenk3e386912003-04-05 00:53:31 +0000204 PDEBUG("thread_yield: %d match, ctx=0x%08x", \
wdenk27b207f2003-07-24 23:38:38 +0000205 new, \
206 (unsigned)lthreads[current_tid].context); \
wdenk85ec0bc2003-03-31 16:34:49 +0000207 if(setjmp(lthreads[current_tid].context) == 0) { \
208 current_tid = new; \
wdenk3e386912003-04-05 00:53:31 +0000209 PDEBUG("thread_yield: tid %d returns 0", \
wdenk85ec0bc2003-03-31 16:34:49 +0000210 new); \
211 longjmp(lthreads[new].context, 1); \
212 } else { \
wdenk3e386912003-04-05 00:53:31 +0000213 PDEBUG("thread_yield: tid %d returns 1", \
wdenk85ec0bc2003-03-31 16:34:49 +0000214 new); \
215 return; \
216 } \
217 }
218
219 for (i = current_tid + 1; i < MAX_THREADS; i++) {
220 SWITCH (i);
221 }
222
223 if (current_tid != 0) {
224 for (i = 0; i <= current_tid; i++) {
225 SWITCH (i);
226 }
227 }
228
wdenk3e386912003-04-05 00:53:31 +0000229 PDEBUG ("thread_yield: returning from thread_yield");
wdenk85ec0bc2003-03-31 16:34:49 +0000230 return;
231}
232
233static int thread_create (int (*func) (void *), void *arg)
234{
235 int i;
236
237 for (i = MASTER_THREAD + 1; i < MAX_THREADS; i++) {
238 if (lthreads[i].state == STATE_EMPTY) {
239 lthreads[i].state = STATE_STOPPED;
240 lthreads[i].func = func;
241 lthreads[i].arg = arg;
wdenk3e386912003-04-05 00:53:31 +0000242 PDEBUG ("thread_create: returns new tid %d", i);
wdenk85ec0bc2003-03-31 16:34:49 +0000243 return i;
244 }
245 }
246
wdenk3e386912003-04-05 00:53:31 +0000247 PDEBUG ("thread_create: returns failure");
wdenk85ec0bc2003-03-31 16:34:49 +0000248 return RC_FAILURE;
249}
250
251static int thread_delete (int id)
252{
253 if (id <= MASTER_THREAD || id > MAX_THREADS)
254 return RC_FAILURE;
255
256 if (current_tid == id)
257 return RC_FAILURE;
258
259 lthreads[id].state = STATE_EMPTY;
260 return RC_SUCCESS;
261}
262
263static void thread_launcher (void)
264{
wdenk3e386912003-04-05 00:53:31 +0000265 PDEBUG ("thread_launcher: invoking func=0x%08x",
wdenk27b207f2003-07-24 23:38:38 +0000266 (unsigned)lthreads[current_tid].func);
wdenk85ec0bc2003-03-31 16:34:49 +0000267
268 lthreads[current_tid].retval =
wdenk3e386912003-04-05 00:53:31 +0000269 lthreads[current_tid].func (lthreads[current_tid].arg);
wdenk85ec0bc2003-03-31 16:34:49 +0000270
wdenk3e386912003-04-05 00:53:31 +0000271 PDEBUG ("thread_launcher: tid %d terminated", current_tid);
wdenk85ec0bc2003-03-31 16:34:49 +0000272
273 lthreads[current_tid].state = STATE_TERMINATED;
274 thread_yield ();
wdenk27b207f2003-07-24 23:38:38 +0000275 printf ("thread_launcher: should NEVER get here!\n");
wdenk85ec0bc2003-03-31 16:34:49 +0000276
277 return;
278}
279
280static int thread_start (int id)
281{
wdenk3e386912003-04-05 00:53:31 +0000282 PDEBUG ("thread_start: id=%d", id);
wdenk85ec0bc2003-03-31 16:34:49 +0000283 if (id <= MASTER_THREAD || id > MAX_THREADS) {
284 return RC_FAILURE;
285 }
286
287 if (lthreads[id].state != STATE_STOPPED)
288 return RC_FAILURE;
289
290 if (setjmp (lthreads[current_tid].context) == 0) {
291 lthreads[id].state = STATE_RUNNABLE;
292 current_tid = id;
wdenk27b207f2003-07-24 23:38:38 +0000293 PDEBUG ("thread_start: to be stack=0%08x",
294 (unsigned)lthreads[id].stack);
Wolfgang Denk77ddac92005-10-13 16:45:02 +0200295 setctxsp ((vu_char *)&lthreads[id].stack[STK_SIZE]);
wdenk85ec0bc2003-03-31 16:34:49 +0000296 thread_launcher ();
297 }
298
wdenk3e386912003-04-05 00:53:31 +0000299 PDEBUG ("thread_start: Thread id=%d started, parent returns", id);
wdenk85ec0bc2003-03-31 16:34:49 +0000300
301 return RC_SUCCESS;
302}
303
wdenk27b207f2003-07-24 23:38:38 +0000304#if 0 /* not used so far */
wdenk85ec0bc2003-03-31 16:34:49 +0000305static int thread_stop (int id)
306{
307 if (id <= MASTER_THREAD || id >= MAX_THREADS)
308 return RC_FAILURE;
309
310 if (current_tid == id)
311 return RC_FAILURE;
312
313 lthreads[id].state = STATE_STOPPED;
314 return RC_SUCCESS;
315}
wdenk27b207f2003-07-24 23:38:38 +0000316#endif /* not used so far */
wdenk85ec0bc2003-03-31 16:34:49 +0000317
318static int thread_join (int *ret)
319{
320 int i, j = 0;
321
wdenk3e386912003-04-05 00:53:31 +0000322 PDEBUG ("thread_join: *ret = %d", *ret);
wdenk85ec0bc2003-03-31 16:34:49 +0000323
324 if (!(*ret == -1 || *ret > MASTER_THREAD || *ret < MAX_THREADS)) {
wdenk3e386912003-04-05 00:53:31 +0000325 PDEBUG ("thread_join: invalid tid %d", *ret);
wdenk85ec0bc2003-03-31 16:34:49 +0000326 return RC_FAILURE;
327 }
328
329 if (*ret == -1) {
wdenk3e386912003-04-05 00:53:31 +0000330 PDEBUG ("Checking for tid = -1");
wdenk85ec0bc2003-03-31 16:34:49 +0000331 while (1) {
wdenk3e386912003-04-05 00:53:31 +0000332 /* PDEBUG("thread_join: start while-loopn"); */
wdenk85ec0bc2003-03-31 16:34:49 +0000333 j = 0;
334 for (i = MASTER_THREAD + 1; i < MAX_THREADS; i++) {
335 if (lthreads[i].state == STATE_TERMINATED) {
336 *ret = lthreads[i].retval;
337 lthreads[i].state = STATE_EMPTY;
wdenk3e386912003-04-05 00:53:31 +0000338 /* PDEBUG("thread_join: returning retval %d of tid %d",
339 ret, i); */
wdenk85ec0bc2003-03-31 16:34:49 +0000340 return RC_SUCCESS;
341 }
342
343 if (lthreads[i].state != STATE_EMPTY) {
wdenk3e386912003-04-05 00:53:31 +0000344 PDEBUG ("thread_join: %d used slots tid %d state=%d",
345 j, i, lthreads[i].state);
wdenk85ec0bc2003-03-31 16:34:49 +0000346 j++;
347 }
348 }
349 if (j == 0) {
wdenk3e386912003-04-05 00:53:31 +0000350 PDEBUG ("thread_join: all slots empty!");
wdenk85ec0bc2003-03-31 16:34:49 +0000351 return RC_FAILURE;
352 }
wdenk3e386912003-04-05 00:53:31 +0000353 /* PDEBUG("thread_join: yielding"); */
wdenk85ec0bc2003-03-31 16:34:49 +0000354 thread_yield ();
wdenk3e386912003-04-05 00:53:31 +0000355 /* PDEBUG("thread_join: back from yield"); */
wdenk85ec0bc2003-03-31 16:34:49 +0000356 }
357 }
358
359 if (lthreads[*ret].state == STATE_TERMINATED) {
360 i = *ret;
361 *ret = lthreads[*ret].retval;
362 lthreads[*ret].state = STATE_EMPTY;
wdenk3e386912003-04-05 00:53:31 +0000363 PDEBUG ("thread_join: returing %d for tid %d", *ret, i);
wdenk85ec0bc2003-03-31 16:34:49 +0000364 return RC_SUCCESS;
365 }
366
wdenk3e386912003-04-05 00:53:31 +0000367 PDEBUG ("thread_join: thread %d is not terminated!", *ret);
wdenk85ec0bc2003-03-31 16:34:49 +0000368 return RC_FAILURE;
369}