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1351 palkovsky 1
/*
2
 * Copyright (C) 2006 Ondrej Palkovsky
3
 * All rights reserved.
4
 *
5
 * Redistribution and use in source and binary forms, with or without
6
 * modification, are permitted provided that the following conditions
7
 * are met:
8
 *
9
 * - Redistributions of source code must retain the above copyright
10
 *   notice, this list of conditions and the following disclaimer.
11
 * - Redistributions in binary form must reproduce the above copyright
12
 *   notice, this list of conditions and the following disclaimer in the
13
 *   documentation and/or other materials provided with the distribution.
14
 * - The name of the author may not be used to endorse or promote products
15
 *   derived from this software without specific prior written permission.
16
 *
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1653 cejka 27
 */
28
 
29
 /** @addtogroup libc
30
 * @{
31
 */
32
/** @file
1351 palkovsky 33
 */
34
 
1392 palkovsky 35
/**
36
 * Asynchronous library
37
 *
38
 * The aim of this library is facilitating writing programs utilizing
39
 * the asynchronous nature of Helenos IPC, yet using a normal way
40
 * of programming.
41
 *
42
 * You should be able to write very simple multithreaded programs,
43
 * the async framework will automatically take care of most synchronization
44
 * problems.
45
 *
46
 * Default semantics:
47
 * - send() - send asynchronously. If the kernel refuses to send more
48
 *            messages, [ try to get responses from kernel, if nothing
49
 *            found, might try synchronous ]
50
 *
51
 * Example of use:
52
 *
53
 * 1) Multithreaded client application
54
 *  create_thread(thread1);
55
 *  create_thread(thread2);
56
 *  ...
57
 *  
58
 *  thread1() {
59
 *        conn = ipc_connect_me_to();
60
 *        c1 = send(conn);
61
 *        c2 = send(conn);
62
 *        wait_for(c1);
63
 *        wait_for(c2);
64
 *  }
65
 *
66
 *
67
 * 2) Multithreaded server application
68
 * main() {
1407 palkovsky 69
 *      async_manager();
1392 palkovsky 70
 * }
71
 *
72
 *
1407 palkovsky 73
 * client_connection(icallid, *icall) {
74
 *       if (want_refuse) {
75
 *           ipc_answer_fast(icallid, ELIMIT, 0, 0);
76
 *           return;
77
 *       }
78
 *       ipc_answer_fast(icallid, 0, 0, 0);
1392 palkovsky 79
 *
1407 palkovsky 80
 *       callid = async_get_call(&call);
81
 *       handle(callid, call);
82
 *       ipc_answer_fast(callid, 1,2,3);
83
 *
84
 *       callid = async_get_call(&call);
1392 palkovsky 85
 *       ....
86
 * }
1404 palkovsky 87
 *
1405 decky 88
 * TODO: Detaching/joining dead psthreads?
1392 palkovsky 89
 */
90
#include <futex.h>
91
#include <async.h>
92
#include <psthread.h>
93
#include <stdio.h>
94
#include <libadt/hash_table.h>
95
#include <libadt/list.h>
96
#include <ipc/ipc.h>
97
#include <assert.h>
98
#include <errno.h>
1441 palkovsky 99
#include <time.h>
100
#include <arch/barrier.h>
1392 palkovsky 101
 
1463 palkovsky 102
atomic_t async_futex = FUTEX_INITIALIZER;
1392 palkovsky 103
static hash_table_t conn_hash_table;
1441 palkovsky 104
static LIST_INITIALIZE(timeout_list);
1392 palkovsky 105
 
106
typedef struct {
1500 palkovsky 107
    struct timeval expires;      /**< Expiration time for waiting thread */
108
    int inlist;             /**< If true, this struct is in timeout list */
109
    link_t link;
110
 
1427 palkovsky 111
    pstid_t ptid;                /**< Thread waiting for this message */
112
    int active;                  /**< If this thread is currently active */
1500 palkovsky 113
    int timedout;                /**< If true, we timed out */
114
} awaiter_t;
115
 
116
typedef struct {
117
    awaiter_t wdata;
118
 
1427 palkovsky 119
    int done;                    /**< If reply was received */
120
    ipc_call_t *dataptr;         /**< Pointer where the answer data
1500 palkovsky 121
                      *   is stored */
1427 palkovsky 122
    ipcarg_t retval;
123
} amsg_t;
124
 
125
typedef struct {
1392 palkovsky 126
    link_t link;
127
    ipc_callid_t callid;
128
    ipc_call_t call;
129
} msg_t;
130
 
131
typedef struct {
1500 palkovsky 132
    awaiter_t wdata;
133
 
134
    link_t link;             /**< Hash table link */
135
    ipcarg_t in_phone_hash;  /**< Incoming phone hash. */
136
    link_t msg_queue;        /**< Messages that should be delivered to this thread */
1392 palkovsky 137
    /* Structures for connection opening packet */
138
    ipc_callid_t callid;
139
    ipc_call_t call;
1648 palkovsky 140
    ipc_callid_t close_callid; /* Identification of closing packet */
1407 palkovsky 141
    void (*cthread)(ipc_callid_t,ipc_call_t *);
1392 palkovsky 142
} connection_t;
143
 
1610 palkovsky 144
/** Identifier of incoming connection handled by current thread */
1392 palkovsky 145
__thread connection_t *PS_connection;
1610 palkovsky 146
/** If true, it is forbidden to use async_req functions and
147
 *  all preemption is disabled */
148
__thread int in_interrupt_handler;
1392 palkovsky 149
 
1490 palkovsky 150
static void default_client_connection(ipc_callid_t callid, ipc_call_t *call);
1596 palkovsky 151
static void default_interrupt_received(ipc_callid_t callid, ipc_call_t *call);
1490 palkovsky 152
static async_client_conn_t client_connection = default_client_connection;
1596 palkovsky 153
static async_client_conn_t interrupt_received = default_interrupt_received;
1490 palkovsky 154
 
1441 palkovsky 155
/** Add microseconds to give timeval */
156
static void tv_add(struct timeval *tv, suseconds_t usecs)
157
{
158
    tv->tv_sec += usecs / 1000000;
159
    tv->tv_usec += usecs % 1000000;
160
    if (tv->tv_usec > 1000000) {
161
        tv->tv_sec++;
162
        tv->tv_usec -= 1000000;
163
    }
164
}
165
 
166
/** Subtract 2 timevals, return microseconds difference */
167
static suseconds_t tv_sub(struct timeval *tv1, struct timeval *tv2)
168
{
169
    suseconds_t result;
170
 
171
    result = tv1->tv_usec - tv2->tv_usec;
172
    result += (tv1->tv_sec - tv2->tv_sec) * 1000000;
173
 
174
    return result;
175
}
176
 
177
/** Compare timeval
178
 *
179
 * @return 1 if tv1 > tv2, otherwise 0
180
 */
181
static int tv_gt(struct timeval *tv1, struct timeval *tv2)
182
{
183
    if (tv1->tv_sec > tv2->tv_sec)
184
        return 1;
185
    if (tv1->tv_sec == tv2->tv_sec && tv1->tv_usec > tv2->tv_usec)
186
        return 1;
187
    return 0;
188
}
1466 palkovsky 189
static int tv_gteq(struct timeval *tv1, struct timeval *tv2)
190
{
191
    if (tv1->tv_sec > tv2->tv_sec)
192
        return 1;
193
    if (tv1->tv_sec == tv2->tv_sec && tv1->tv_usec >= tv2->tv_usec)
194
        return 1;
195
    return 0;
196
}
1441 palkovsky 197
 
1392 palkovsky 198
/* Hash table functions */
1404 palkovsky 199
#define CONN_HASH_TABLE_CHAINS  32
1392 palkovsky 200
 
201
static hash_index_t conn_hash(unsigned long *key)
1351 palkovsky 202
{
1392 palkovsky 203
    assert(key);
1404 palkovsky 204
    return ((*key) >> 4) % CONN_HASH_TABLE_CHAINS;
1351 palkovsky 205
}
206
 
1392 palkovsky 207
static int conn_compare(unsigned long key[], hash_count_t keys, link_t *item)
1351 palkovsky 208
{
1392 palkovsky 209
    connection_t *hs;
210
 
211
    hs = hash_table_get_instance(item, connection_t, link);
212
 
213
    return key[0] == hs->in_phone_hash;
1351 palkovsky 214
}
215
 
1392 palkovsky 216
static void conn_remove(link_t *item)
1351 palkovsky 217
{
1392 palkovsky 218
    free(hash_table_get_instance(item, connection_t, link));
1351 palkovsky 219
}
220
 
1392 palkovsky 221
 
222
/** Operations for NS hash table. */
223
static hash_table_operations_t conn_hash_table_ops = {
224
    .hash = conn_hash,
225
    .compare = conn_compare,
226
    .remove_callback = conn_remove
227
};
228
 
1500 palkovsky 229
/** Insert sort timeout msg into timeouts list
230
 *
231
 */
232
static void insert_timeout(awaiter_t *wd)
233
{
234
    link_t *tmp;
235
    awaiter_t *cur;
236
 
237
    wd->timedout = 0;
1610 palkovsky 238
    wd->inlist = 1;
1500 palkovsky 239
 
240
    tmp = timeout_list.next;
241
    while (tmp != &timeout_list) {
242
        cur = list_get_instance(tmp, awaiter_t, link);
243
        if (tv_gteq(&cur->expires, &wd->expires))
244
            break;
245
        tmp = tmp->next;
246
    }
247
    list_append(&wd->link, tmp);
248
}
249
 
1427 palkovsky 250
/*************************************************/
251
 
1392 palkovsky 252
/** Try to route a call to an appropriate connection thread
253
 *
254
 */
255
static int route_call(ipc_callid_t callid, ipc_call_t *call)
1351 palkovsky 256
{
1392 palkovsky 257
    connection_t *conn;
258
    msg_t *msg;
259
    link_t *hlp;
260
    unsigned long key;
261
 
1427 palkovsky 262
    futex_down(&async_futex);
1392 palkovsky 263
 
264
    key = call->in_phone_hash;
265
    hlp = hash_table_find(&conn_hash_table, &key);
266
    if (!hlp) {
1427 palkovsky 267
        futex_up(&async_futex);
1392 palkovsky 268
        return 0;
1351 palkovsky 269
    }
1392 palkovsky 270
    conn = hash_table_get_instance(hlp, connection_t, link);
1351 palkovsky 271
 
1392 palkovsky 272
    msg = malloc(sizeof(*msg));
273
    msg->callid = callid;
274
    msg->call = *call;
275
    list_append(&msg->link, &conn->msg_queue);
1648 palkovsky 276
 
277
    if (IPC_GET_METHOD(*call) == IPC_M_PHONE_HUNGUP)
278
        conn->close_callid = callid;
1392 palkovsky 279
 
1500 palkovsky 280
    /* If the call is waiting for event, run it */
281
    if (!conn->wdata.active) {
282
        /* If in timeout list, remove it */
283
        if (conn->wdata.inlist) {
284
            conn->wdata.inlist = 0;
285
            list_remove(&conn->wdata.link);
286
        }
287
        conn->wdata.active = 1;
288
        psthread_add_ready(conn->wdata.ptid);
1392 palkovsky 289
    }
1351 palkovsky 290
 
1427 palkovsky 291
    futex_up(&async_futex);
1392 palkovsky 292
 
293
    return 1;
294
}
295
 
1404 palkovsky 296
/** Return new incoming message for current(thread-local) connection */
1500 palkovsky 297
ipc_callid_t async_get_call_timeout(ipc_call_t *call, suseconds_t usecs)
1392 palkovsky 298
{
299
    msg_t *msg;
300
    ipc_callid_t callid;
1536 palkovsky 301
    connection_t *conn;
1392 palkovsky 302
 
1466 palkovsky 303
    assert(PS_connection);
1536 palkovsky 304
    /* GCC 4.1.0 coughs on PS_connection-> dereference,
305
     * GCC 4.1.1 happilly puts the rdhwr instruction in delay slot.
306
     *           I would never expect to find so many errors in
307
     *           compiler *($&$(*&$
308
     */
309
    conn = PS_connection;
1466 palkovsky 310
 
1427 palkovsky 311
    futex_down(&async_futex);
1392 palkovsky 312
 
1500 palkovsky 313
    if (usecs) {
1536 palkovsky 314
        gettimeofday(&conn->wdata.expires, NULL);
315
        tv_add(&conn->wdata.expires, usecs);
1500 palkovsky 316
    } else {
1536 palkovsky 317
        conn->wdata.inlist = 0;
1500 palkovsky 318
    }
1392 palkovsky 319
    /* If nothing in queue, wait until something appears */
1536 palkovsky 320
    while (list_empty(&conn->msg_queue)) {
1610 palkovsky 321
        if (usecs)
1536 palkovsky 322
            insert_timeout(&conn->wdata);
1610 palkovsky 323
 
1536 palkovsky 324
        conn->wdata.active = 0;
1392 palkovsky 325
        psthread_schedule_next_adv(PS_TO_MANAGER);
1500 palkovsky 326
        /* Futex is up after getting back from async_manager
327
         * get it again */
328
        futex_down(&async_futex);
1536 palkovsky 329
        if (usecs && conn->wdata.timedout && \
330
            list_empty(&conn->msg_queue)) {
1500 palkovsky 331
            /* If we timed out-> exit */
332
            futex_up(&async_futex);
333
            return 0;
334
        }
1351 palkovsky 335
    }
336
 
1536 palkovsky 337
    msg = list_get_instance(conn->msg_queue.next, msg_t, link);
1392 palkovsky 338
    list_remove(&msg->link);
339
    callid = msg->callid;
340
    *call = msg->call;
341
    free(msg);
342
 
1427 palkovsky 343
    futex_up(&async_futex);
1392 palkovsky 344
    return callid;
1351 palkovsky 345
}
346
 
1404 palkovsky 347
/** Thread function that gets created on new connection
348
 *
349
 * This function is defined as a weak symbol - to be redefined in
350
 * user code.
351
 */
1490 palkovsky 352
static void default_client_connection(ipc_callid_t callid, ipc_call_t *call)
1392 palkovsky 353
{
1404 palkovsky 354
    ipc_answer_fast(callid, ENOENT, 0, 0);
1392 palkovsky 355
}
1596 palkovsky 356
static void default_interrupt_received(ipc_callid_t callid, ipc_call_t *call)
1452 palkovsky 357
{
358
}
359
 
1404 palkovsky 360
/** Wrapper for client connection thread
361
 *
362
 * When new connection arrives, thread with this function is created.
363
 * It calls client_connection and does final cleanup.
364
 *
1653 cejka 365
 * @param arg Connection structure pointer
1404 palkovsky 366
 */
1392 palkovsky 367
static int connection_thread(void  *arg)
1351 palkovsky 368
{
1404 palkovsky 369
    unsigned long key;
370
    msg_t *msg;
1648 palkovsky 371
    int close_answered = 0;
1404 palkovsky 372
 
1392 palkovsky 373
    /* Setup thread local connection pointer */
374
    PS_connection = (connection_t *)arg;
1470 palkovsky 375
    PS_connection->cthread(PS_connection->callid, &PS_connection->call);
1404 palkovsky 376
    /* Remove myself from connection hash table */
1427 palkovsky 377
    futex_down(&async_futex);
1470 palkovsky 378
    key = PS_connection->in_phone_hash;
1404 palkovsky 379
    hash_table_remove(&conn_hash_table, &key, 1);
1427 palkovsky 380
    futex_up(&async_futex);
1404 palkovsky 381
    /* Answer all remaining messages with ehangup */
1470 palkovsky 382
    while (!list_empty(&PS_connection->msg_queue)) {
383
        msg = list_get_instance(PS_connection->msg_queue.next, msg_t, link);
1404 palkovsky 384
        list_remove(&msg->link);
1648 palkovsky 385
        if (msg->callid == PS_connection->close_callid)
386
            close_answered = 1;
1404 palkovsky 387
        ipc_answer_fast(msg->callid, EHANGUP, 0, 0);
388
        free(msg);
389
    }
1648 palkovsky 390
    if (PS_connection->close_callid)
391
        ipc_answer_fast(PS_connection->close_callid, 0, 0, 0);
1351 palkovsky 392
}
1392 palkovsky 393
 
394
/** Create new thread for a new connection
395
 *
396
 * Creates new thread for connection, fills in connection
397
 * structures and inserts it into the hash table, so that
398
 * later we can easily do routing of messages to particular
399
 * threads.
1407 palkovsky 400
 *
1452 palkovsky 401
 * @param in_phone_hash Identification of the incoming connection
1407 palkovsky 402
 * @param callid Callid of the IPC_M_CONNECT_ME_TO packet
403
 * @param call Call data of the opening packet
404
 * @param cthread Thread function that should be called upon
405
 *                opening the connection
406
 * @return New thread id
1392 palkovsky 407
 */
1452 palkovsky 408
pstid_t async_new_connection(ipcarg_t in_phone_hash,ipc_callid_t callid,
409
                 ipc_call_t *call,
1407 palkovsky 410
                 void (*cthread)(ipc_callid_t,ipc_call_t *))
1392 palkovsky 411
{
412
    pstid_t ptid;
413
    connection_t *conn;
414
    unsigned long key;
415
 
416
    conn = malloc(sizeof(*conn));
417
    if (!conn) {
418
        ipc_answer_fast(callid, ENOMEM, 0, 0);
1407 palkovsky 419
        return NULL;
1392 palkovsky 420
    }
1452 palkovsky 421
    conn->in_phone_hash = in_phone_hash;
1392 palkovsky 422
    list_initialize(&conn->msg_queue);
423
    conn->callid = callid;
1648 palkovsky 424
    conn->close_callid = 0;
1453 palkovsky 425
    if (call)
426
        conn->call = *call;
1500 palkovsky 427
    conn->wdata.active = 1; /* We will activate it asap */
1407 palkovsky 428
    conn->cthread = cthread;
1500 palkovsky 429
 
430
    conn->wdata.ptid = psthread_create(connection_thread, conn);
431
    if (!conn->wdata.ptid) {
1392 palkovsky 432
        free(conn);
433
        ipc_answer_fast(callid, ENOMEM, 0, 0);
1407 palkovsky 434
        return NULL;
1392 palkovsky 435
    }
1500 palkovsky 436
    /* Add connection to hash table */
1392 palkovsky 437
    key = conn->in_phone_hash;
1427 palkovsky 438
    futex_down(&async_futex);
1392 palkovsky 439
    hash_table_insert(&conn_hash_table, &key, &conn->link);
1427 palkovsky 440
    futex_up(&async_futex);
1392 palkovsky 441
 
1500 palkovsky 442
    psthread_add_ready(conn->wdata.ptid);
1407 palkovsky 443
 
1500 palkovsky 444
    return conn->wdata.ptid;
1392 palkovsky 445
}
446
 
1427 palkovsky 447
/** Handle call that was received */
1392 palkovsky 448
static void handle_call(ipc_callid_t callid, ipc_call_t *call)
449
{
1452 palkovsky 450
    /* Unrouted call - do some default behaviour */
1694 palkovsky 451
    if ((callid & IPC_CALLID_NOTIFICATION)) {
1610 palkovsky 452
        in_interrupt_handler = 1;
1596 palkovsky 453
        (*interrupt_received)(callid,call);
1610 palkovsky 454
        in_interrupt_handler = 0;
1452 palkovsky 455
        return;
1694 palkovsky 456
    }      
457
 
458
    switch (IPC_GET_METHOD(*call)) {
1392 palkovsky 459
    case IPC_M_CONNECT_ME_TO:
460
        /* Open new connection with thread etc. */
1452 palkovsky 461
        async_new_connection(IPC_GET_ARG3(*call), callid, call, client_connection);
462
        return;
1392 palkovsky 463
    }
1452 palkovsky 464
 
465
    /* Try to route call through connection tables */
466
    if (route_call(callid, call))
467
        return;
468
 
469
    /* Unknown call from unknown phone - hang it up */
470
    ipc_answer_fast(callid, EHANGUP, 0, 0);
1392 palkovsky 471
}
472
 
1536 palkovsky 473
/** Fire all timeouts that expired
474
 *
475
 */
1441 palkovsky 476
static void handle_expired_timeouts(void)
477
{
478
    struct timeval tv;
1500 palkovsky 479
    awaiter_t *waiter;
1441 palkovsky 480
    link_t *cur;
481
 
482
    gettimeofday(&tv,NULL);
483
    futex_down(&async_futex);
484
 
485
    cur = timeout_list.next;
486
    while (cur != &timeout_list) {
1500 palkovsky 487
        waiter = list_get_instance(cur,awaiter_t,link);
488
        if (tv_gt(&waiter->expires, &tv))
1441 palkovsky 489
            break;
490
        cur = cur->next;
1500 palkovsky 491
        list_remove(&waiter->link);
492
        waiter->inlist = 0;
493
        waiter->timedout = 1;
1441 palkovsky 494
        /* Redundant condition? The thread should not
495
         * be active when it gets here.
496
         */
1500 palkovsky 497
        if (!waiter->active) {
498
            waiter->active = 1;
499
            psthread_add_ready(waiter->ptid);
1441 palkovsky 500
        }
501
    }
502
 
503
    futex_up(&async_futex);
504
}
505
 
1392 palkovsky 506
/** Endless loop dispatching incoming calls and answers */
1610 palkovsky 507
static int async_manager_worker(void)
1392 palkovsky 508
{
509
    ipc_call_t call;
510
    ipc_callid_t callid;
1435 palkovsky 511
    int timeout;
1500 palkovsky 512
    awaiter_t *waiter;
1441 palkovsky 513
    struct timeval tv;
1392 palkovsky 514
 
515
    while (1) {
516
        if (psthread_schedule_next_adv(PS_FROM_MANAGER)) {
1427 palkovsky 517
            futex_up(&async_futex); /* async_futex is always held
1392 palkovsky 518
                        * when entering manager thread
519
                        */
520
            continue;
521
        }
1441 palkovsky 522
        futex_down(&async_futex);
523
        if (!list_empty(&timeout_list)) {
1500 palkovsky 524
            waiter = list_get_instance(timeout_list.next,awaiter_t,link);
1441 palkovsky 525
            gettimeofday(&tv,NULL);
1500 palkovsky 526
            if (tv_gteq(&tv, &waiter->expires)) {
1536 palkovsky 527
                futex_up(&async_futex);
1441 palkovsky 528
                handle_expired_timeouts();
529
                continue;
530
            } else
1500 palkovsky 531
                timeout = tv_sub(&waiter->expires, &tv);
1441 palkovsky 532
        } else
1435 palkovsky 533
            timeout = SYNCH_NO_TIMEOUT;
1441 palkovsky 534
        futex_up(&async_futex);
535
 
1503 jermar 536
        callid = ipc_wait_cycle(&call, timeout, SYNCH_FLAGS_NONE);
1392 palkovsky 537
 
1435 palkovsky 538
        if (!callid) {
1441 palkovsky 539
            handle_expired_timeouts();
1435 palkovsky 540
            continue;
541
        }
542
 
1610 palkovsky 543
        if (callid & IPC_CALLID_ANSWERED) {
1392 palkovsky 544
            continue;
1610 palkovsky 545
        }
1427 palkovsky 546
 
1392 palkovsky 547
        handle_call(callid, &call);
548
    }
549
}
550
 
1404 palkovsky 551
/** Function to start async_manager as a standalone thread
552
 *
553
 * When more kernel threads are used, one async manager should
554
 * exist per thread. The particular implementation may change,
555
 * currently one async_manager is started automatically per kernel
556
 * thread except main thread.
557
 */
1392 palkovsky 558
static int async_manager_thread(void *arg)
559
{
1427 palkovsky 560
    futex_up(&async_futex); /* async_futex is always locked when entering
1392 palkovsky 561
                * manager */
1610 palkovsky 562
    async_manager_worker();
1392 palkovsky 563
}
564
 
565
/** Add one manager to manager list */
566
void async_create_manager(void)
567
{
568
    pstid_t ptid;
569
 
570
    ptid = psthread_create(async_manager_thread, NULL);
571
    psthread_add_manager(ptid);
572
}
573
 
574
/** Remove one manager from manager list */
575
void async_destroy_manager(void)
576
{
577
    psthread_remove_manager();
578
}
579
 
580
/** Initialize internal structures needed for async manager */
581
int _async_init(void)
582
{
1404 palkovsky 583
    if (!hash_table_create(&conn_hash_table, CONN_HASH_TABLE_CHAINS, 1, &conn_hash_table_ops)) {
1392 palkovsky 584
        printf("%s: cannot create hash table\n", "async");
585
        return ENOMEM;
586
    }
587
 
588
}
1427 palkovsky 589
 
590
/** IPC handler for messages in async framework
591
 *
592
 * Notify thread that is waiting for this message, that it arrived
593
 */
594
static void reply_received(void *private, int retval,
595
               ipc_call_t *data)
596
{
597
    amsg_t *msg = (amsg_t *) private;
598
 
599
    msg->retval = retval;
600
 
601
    futex_down(&async_futex);
602
    /* Copy data after futex_down, just in case the
603
     * call was detached
604
     */
605
    if (msg->dataptr)
606
        *msg->dataptr = *data;
1435 palkovsky 607
 
1441 palkovsky 608
    write_barrier();
609
    /* Remove message from timeout list */
1500 palkovsky 610
    if (msg->wdata.inlist)
611
        list_remove(&msg->wdata.link);
1427 palkovsky 612
    msg->done = 1;
1500 palkovsky 613
    if (! msg->wdata.active) {
614
        msg->wdata.active = 1;
615
        psthread_add_ready(msg->wdata.ptid);
1427 palkovsky 616
    }
617
    futex_up(&async_futex);
618
}
619
 
620
/** Send message and return id of the sent message
621
 *
622
 * The return value can be used as input for async_wait() to wait
623
 * for completion.
624
 */
625
aid_t async_send_2(int phoneid, ipcarg_t method, ipcarg_t arg1, ipcarg_t arg2,
626
           ipc_call_t *dataptr)
627
{
628
    amsg_t *msg;
629
 
1610 palkovsky 630
    if (in_interrupt_handler) {
631
        printf("Cannot send asynchronou request in interrupt handler.\n");
632
        _exit(1);
633
    }
634
 
1427 palkovsky 635
    msg = malloc(sizeof(*msg));
636
    msg->done = 0;
637
    msg->dataptr = dataptr;
1500 palkovsky 638
 
639
    msg->wdata.active = 1; /* We may sleep in next method, but it
640
                * will use it's own mechanism */
1518 palkovsky 641
    ipc_call_async_2(phoneid,method,arg1,arg2,msg,reply_received,1);
1427 palkovsky 642
 
643
    return (aid_t) msg;
644
}
645
 
1547 palkovsky 646
/** Send message and return id of the sent message
647
 *
648
 * The return value can be used as input for async_wait() to wait
649
 * for completion.
650
 */
651
aid_t async_send_3(int phoneid, ipcarg_t method, ipcarg_t arg1, ipcarg_t arg2,
652
           ipcarg_t arg3, ipc_call_t *dataptr)
653
{
654
    amsg_t *msg;
655
 
1610 palkovsky 656
    if (in_interrupt_handler) {
657
        printf("Cannot send asynchronou request in interrupt handler.\n");
658
        _exit(1);
659
    }
660
 
1547 palkovsky 661
    msg = malloc(sizeof(*msg));
662
    msg->done = 0;
663
    msg->dataptr = dataptr;
664
 
665
    msg->wdata.active = 1; /* We may sleep in next method, but it
666
                * will use it's own mechanism */
667
    ipc_call_async_3(phoneid,method,arg1,arg2,arg3, msg,reply_received,1);
668
 
669
    return (aid_t) msg;
670
}
671
 
1427 palkovsky 672
/** Wait for a message sent by async framework
673
 *
674
 * @param amsgid Message ID to wait for
675
 * @param retval Pointer to variable where will be stored retval
676
 *               of the answered message. If NULL, it is ignored.
677
 *
678
 */
679
void async_wait_for(aid_t amsgid, ipcarg_t *retval)
680
{
681
    amsg_t *msg = (amsg_t *) amsgid;
682
    connection_t *conn;
683
 
684
    futex_down(&async_futex);
685
    if (msg->done) {
686
        futex_up(&async_futex);
687
        goto done;
688
    }
689
 
1500 palkovsky 690
    msg->wdata.ptid = psthread_get_id();
691
    msg->wdata.active = 0;
692
    msg->wdata.inlist = 0;
1427 palkovsky 693
    /* Leave locked async_futex when entering this function */
694
    psthread_schedule_next_adv(PS_TO_MANAGER);
695
    /* futex is up automatically after psthread_schedule_next...*/
696
done:
697
    if (retval)
698
        *retval = msg->retval;
699
    free(msg);
700
}
1435 palkovsky 701
 
1441 palkovsky 702
/** Wait for a message sent by async framework with timeout
703
 *
704
 * @param amsgid Message ID to wait for
705
 * @param retval Pointer to variable where will be stored retval
706
 *               of the answered message. If NULL, it is ignored.
707
 * @param timeout Timeout in usecs
708
 * @return 0 on success, ETIMEOUT if timeout expired
709
 *
710
 */
711
int async_wait_timeout(aid_t amsgid, ipcarg_t *retval, suseconds_t timeout)
712
{
713
    amsg_t *msg = (amsg_t *) amsgid;
714
    connection_t *conn;
1435 palkovsky 715
 
1532 palkovsky 716
    /* TODO: Let it go through the event read at least once */
717
    if (timeout < 0)
718
        return ETIMEOUT;
719
 
1441 palkovsky 720
    futex_down(&async_futex);
721
    if (msg->done) {
722
        futex_up(&async_futex);
723
        goto done;
724
    }
1435 palkovsky 725
 
1500 palkovsky 726
    gettimeofday(&msg->wdata.expires, NULL);
727
    tv_add(&msg->wdata.expires, timeout);
1435 palkovsky 728
 
1500 palkovsky 729
    msg->wdata.ptid = psthread_get_id();
730
    msg->wdata.active = 0;
731
    insert_timeout(&msg->wdata);
732
 
1441 palkovsky 733
    /* Leave locked async_futex when entering this function */
734
    psthread_schedule_next_adv(PS_TO_MANAGER);
735
    /* futex is up automatically after psthread_schedule_next...*/
1435 palkovsky 736
 
1441 palkovsky 737
    if (!msg->done)
738
        return ETIMEOUT;
739
 
740
done:
741
    if (retval)
742
        *retval = msg->retval;
743
    free(msg);
744
 
745
    return 0;
746
}
747
 
1452 palkovsky 748
/** Wait specified time, but in the meantime handle incoming events
749
 *
750
 * @param timeout Time in microseconds to wait
751
 */
752
void async_usleep(suseconds_t timeout)
753
{
754
    amsg_t *msg;
755
 
1610 palkovsky 756
    if (in_interrupt_handler) {
757
        printf("Cannot call async_usleep in interrupt handler.\n");
758
        _exit(1);
759
    }
760
 
1452 palkovsky 761
    msg = malloc(sizeof(*msg));
762
    if (!msg)
763
        return;
764
 
1500 palkovsky 765
    msg->wdata.ptid = psthread_get_id();
766
    msg->wdata.active = 0;
1452 palkovsky 767
 
1500 palkovsky 768
    gettimeofday(&msg->wdata.expires, NULL);
769
    tv_add(&msg->wdata.expires, timeout);
1452 palkovsky 770
 
771
    futex_down(&async_futex);
1500 palkovsky 772
    insert_timeout(&msg->wdata);
1452 palkovsky 773
    /* Leave locked async_futex when entering this function */
774
    psthread_schedule_next_adv(PS_TO_MANAGER);
775
    /* futex is up automatically after psthread_schedule_next...*/
776
    free(msg);
777
}
1490 palkovsky 778
 
779
/** Set function that is called, IPC_M_CONNECT_ME_TO is received
780
 *
781
 * @param conn Function that will form new psthread.
782
 */
783
void async_set_client_connection(async_client_conn_t conn)
784
{
785
    client_connection = conn;
786
}
1596 palkovsky 787
void async_set_interrupt_received(async_client_conn_t conn)
788
{
789
    interrupt_received = conn;
790
}
1610 palkovsky 791
 
792
/* Primitive functions for simple communication */
793
void async_msg_3(int phoneid, ipcarg_t method, ipcarg_t arg1,
794
         ipcarg_t arg2, ipcarg_t arg3)
795
{
796
    ipc_call_async_3(phoneid, method, arg1, arg2, arg3, NULL, NULL, !in_interrupt_handler);
797
}
798
 
799
void async_msg_2(int phoneid, ipcarg_t method, ipcarg_t arg1, ipcarg_t arg2)
800
{
801
    ipc_call_async_2(phoneid, method, arg1, arg2, NULL, NULL, !in_interrupt_handler);
802
}
1653 cejka 803
 
804
 
805
 /** @}
806
 */
807
 
808