ceph/src/dpdk/examples/performance-thread/common/lthread.c

   1 /*-
   2  *   BSD LICENSE
   3  *
   4  *   Copyright(c) 2015 Intel Corporation. All rights reserved.
   5  *   All rights reserved.
   6  *
   7  *   Redistribution and use in source and binary forms, with or without
   8  *   modification, are permitted provided that the following conditions
   9  *   are met:
  10  *
  11  *     * Redistributions of source code must retain the above copyright
  12  *       notice, this list of conditions and the following disclaimer.
  13  *     * Redistributions in binary form must reproduce the above copyright
  14  *       notice, this list of conditions and the following disclaimer in
  15  *       the documentation and/or other materials provided with the
  16  *       distribution.
  17  *     * Neither the name of Intel Corporation nor the names of its
  18  *       contributors may be used to endorse or promote products derived
  19  *       from this software without specific prior written permission.
  20  *
  21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 /*
  35  * Some portions of this software is derived from the
  36  * https://github.com/halayli/lthread which carrys the following license.
  37  *
  38  * Copyright (C) 2012, Hasan Alayli <halayli@gmail.com>
  39  *
  40  * Redistribution and use in source and binary forms, with or without
  41  * modification, are permitted provided that the following conditions
  42  * are met:
  43  * 1. Redistributions of source code must retain the above copyright
  44  *    notice, this list of conditions and the following disclaimer.
  45  * 2. Redistributions in binary form must reproduce the above copyright
  46  *    notice, this list of conditions and the following disclaimer in the
  47  *    documentation and/or other materials provided with the distribution.
  48  *
  49  * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  50  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  51  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  52  * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
  53  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  54  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  55  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  56  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  57  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  58  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  59  * SUCH DAMAGE.
  60  */
  61
  62 #define RTE_MEM 1
  63
  64 #include <stdio.h>
  65 #include <stdlib.h>
  66 #include <string.h>
  67 #include <stdint.h>
  68 #include <stddef.h>
  69 #include <limits.h>
  70 #include <inttypes.h>
  71 #include <unistd.h>
  72 #include <pthread.h>
  73 #include <fcntl.h>
  74 #include <sys/time.h>
  75 #include <sys/mman.h>
  76
  77 #include <rte_log.h>
  78 #include <ctx.h>
  79
  80 #include "lthread_api.h"
  81 #include "lthread.h"
  82 #include "lthread_timer.h"
  83 #include "lthread_tls.h"
  84 #include "lthread_objcache.h"
  85 #include "lthread_diag.h"
  86
  87
  88 /*
  89  * This function gets called after an lthread function has returned.
  90  */
  91 void _lthread_exit_handler(struct lthread *lt)
  92 {
  93
  94         lt->state |= BIT(ST_LT_EXITED);
  95
  96         if (!(lt->state & BIT(ST_LT_DETACH))) {
  97                 /* thread is this not explicitly detached
  98                  * it must be joinable, so we call lthread_exit().
  99                  */
 100                 lthread_exit(NULL);
 101         }
 102
 103         /* if we get here the thread is detached so we can reschedule it,
 104          * allowing the scheduler to free it
 105          */
 106         _reschedule();
 107 }
 108
 109
 110 /*
 111  * Free resources allocated to an lthread
 112  */
 113 void _lthread_free(struct lthread *lt)
 114 {
 115
 116         DIAG_EVENT(lt, LT_DIAG_LTHREAD_FREE, lt, 0);
 117
 118         /* invoke any user TLS destructor functions */
 119         _lthread_tls_destroy(lt);
 120
 121         /* free memory allocated for TLS defined using RTE_PER_LTHREAD macros */
 122         if (sizeof(void *) < (uint64_t)RTE_PER_LTHREAD_SECTION_SIZE)
 123                 _lthread_objcache_free(lt->tls->root_sched->per_lthread_cache,
 124                                         lt->per_lthread_data);
 125
 126         /* free pthread style TLS memory */
 127         _lthread_objcache_free(lt->tls->root_sched->tls_cache, lt->tls);
 128
 129         /* free the stack */
 130         _lthread_objcache_free(lt->stack_container->root_sched->stack_cache,
 131                                 lt->stack_container);
 132
 133         /* now free the thread */
 134         _lthread_objcache_free(lt->root_sched->lthread_cache, lt);
 135
 136 }
 137
 138 /*
 139  * Allocate a stack and maintain a cache of stacks
 140  */
 141 struct lthread_stack *_stack_alloc(void)
 142 {
 143         struct lthread_stack *s;
 144
 145         s = _lthread_objcache_alloc((THIS_SCHED)->stack_cache);
 146         RTE_ASSERT(s != NULL);
 147
 148         s->root_sched = THIS_SCHED;
 149         s->stack_size = LTHREAD_MAX_STACK_SIZE;
 150         return s;
 151 }
 152
 153 /*
 154  * Execute a ctx by invoking the start function
 155  * On return call an exit handler if the user has provided one
 156  */
 157 static void _lthread_exec(void *arg)
 158 {
 159         struct lthread *lt = (struct lthread *)arg;
 160
 161         /* invoke the contexts function */
 162         lt->fun(lt->arg);
 163         /* do exit handling */
 164         if (lt->exit_handler != NULL)
 165                 lt->exit_handler(lt);
 166 }
 167
 168 /*
 169  *      Initialize an lthread
 170  *      Set its function, args, and exit handler
 171  */
 172 void
 173 _lthread_init(struct lthread *lt,
 174         lthread_func_t fun, void *arg, lthread_exit_func exit_handler)
 175 {
 176
 177         /* set ctx func and args */
 178         lt->fun = fun;
 179         lt->arg = arg;
 180         lt->exit_handler = exit_handler;
 181
 182         /* set initial state */
 183         lt->birth = _sched_now();
 184         lt->state = BIT(ST_LT_INIT);
 185         lt->join = LT_JOIN_INITIAL;
 186 }
 187
 188 /*
 189  *      set the lthread stack
 190  */
 191 void _lthread_set_stack(struct lthread *lt, void *stack, size_t stack_size)
 192 {
 193         char *stack_top = (char *)stack + stack_size;
 194         void **s = (void **)stack_top;
 195
 196         /* set stack */
 197         lt->stack = stack;
 198         lt->stack_size = stack_size;
 199
 200         /* set initial context */
 201         s[-3] = NULL;
 202         s[-2] = (void *)lt;
 203         lt->ctx.rsp = (void *)(stack_top - (4 * sizeof(void *)));
 204         lt->ctx.rbp = (void *)(stack_top - (3 * sizeof(void *)));
 205         lt->ctx.rip = (void *)_lthread_exec;
 206 }
 207
 208 /*
 209  * Create an lthread on the current scheduler
 210  * If there is no current scheduler on this pthread then first create one
 211  */
 212 int
 213 lthread_create(struct lthread **new_lt, int lcore_id,
 214                 lthread_func_t fun, void *arg)
 215 {
 216         if ((new_lt == NULL) || (fun == NULL))
 217                 return POSIX_ERRNO(EINVAL);
 218
 219         if (lcore_id < 0)
 220                 lcore_id = rte_lcore_id();
 221         else if (lcore_id > LTHREAD_MAX_LCORES)
 222                 return POSIX_ERRNO(EINVAL);
 223
 224         struct lthread *lt = NULL;
 225
 226         if (THIS_SCHED == NULL) {
 227                 THIS_SCHED = _lthread_sched_create(0);
 228                 if (THIS_SCHED == NULL) {
 229                         perror("Failed to create scheduler");
 230                         return POSIX_ERRNO(EAGAIN);
 231                 }
 232         }
 233
 234         /* allocate a thread structure */
 235         lt = _lthread_objcache_alloc((THIS_SCHED)->lthread_cache);
 236         if (lt == NULL)
 237                 return POSIX_ERRNO(EAGAIN);
 238
 239         bzero(lt, sizeof(struct lthread));
 240         lt->root_sched = THIS_SCHED;
 241
 242         /* set the function args and exit handlder */
 243         _lthread_init(lt, fun, arg, _lthread_exit_handler);
 244
 245         /* put it in the ready queue */
 246         *new_lt = lt;
 247
 248         if (lcore_id < 0)
 249                 lcore_id = rte_lcore_id();
 250
 251         DIAG_CREATE_EVENT(lt, LT_DIAG_LTHREAD_CREATE);
 252
 253         rte_wmb();
 254         _ready_queue_insert(_lthread_sched_get(lcore_id), lt);
 255         return 0;
 256 }
 257
 258 /*
 259  * Schedules lthread to sleep for `nsecs`
 260  * setting the lthread state to LT_ST_SLEEPING.
 261  * lthread state is cleared upon resumption or expiry.
 262  */
 263 static inline void _lthread_sched_sleep(struct lthread *lt, uint64_t nsecs)
 264 {
 265         uint64_t state = lt->state;
 266         uint64_t clks = _ns_to_clks(nsecs);
 267
 268         if (clks) {
 269                 _timer_start(lt, clks);
 270                 lt->state = state | BIT(ST_LT_SLEEPING);
 271         }
 272         DIAG_EVENT(lt, LT_DIAG_LTHREAD_SLEEP, clks, 0);
 273         _suspend();
 274 }
 275
 276
 277
 278 /*
 279  * Cancels any running timer.
 280  * This can be called multiple times on the same lthread regardless if it was
 281  * sleeping or not.
 282  */
 283 int _lthread_desched_sleep(struct lthread *lt)
 284 {
 285         uint64_t state = lt->state;
 286
 287         if (state & BIT(ST_LT_SLEEPING)) {
 288                 _timer_stop(lt);
 289                 state &= (CLEARBIT(ST_LT_SLEEPING) & CLEARBIT(ST_LT_EXPIRED));
 290                 lt->state = state | BIT(ST_LT_READY);
 291                 return 1;
 292         }
 293         return 0;
 294 }
 295
 296 /*
 297  * set user data pointer in an lthread
 298  */
 299 void lthread_set_data(void *data)
 300 {
 301         if (sizeof(void *) == RTE_PER_LTHREAD_SECTION_SIZE)
 302                 THIS_LTHREAD->per_lthread_data = data;
 303 }
 304
 305 /*
 306  * Retrieve user data pointer from an lthread
 307  */
 308 void *lthread_get_data(void)
 309 {
 310         return THIS_LTHREAD->per_lthread_data;
 311 }
 312
 313 /*
 314  * Return the current lthread handle
 315  */
 316 struct lthread *lthread_current(void)
 317 {
 318         struct lthread_sched *sched = THIS_SCHED;
 319
 320         if (sched)
 321                 return sched->current_lthread;
 322         return NULL;
 323 }
 324
 325
 326
 327 /*
 328  * Tasklet to cancel a thread
 329  */
 330 static void
 331 _cancel(void *arg)
 332 {
 333         struct lthread *lt = (struct lthread *) arg;
 334
 335         lt->state |= BIT(ST_LT_CANCELLED);
 336         lthread_detach();
 337 }
 338
 339
 340 /*
 341  * Mark the specified as canceled
 342  */
 343 int lthread_cancel(struct lthread *cancel_lt)
 344 {
 345         struct lthread *lt;
 346
 347         if ((cancel_lt == NULL) || (cancel_lt == THIS_LTHREAD))
 348                 return POSIX_ERRNO(EINVAL);
 349
 350         DIAG_EVENT(cancel_lt, LT_DIAG_LTHREAD_CANCEL, cancel_lt, 0);
 351
 352         if (cancel_lt->sched != THIS_SCHED) {
 353
 354                 /* spawn task-let to cancel the thread */
 355                 lthread_create(&lt,
 356                                 cancel_lt->sched->lcore_id,
 357                                 _cancel,
 358                                 cancel_lt);
 359                 return 0;
 360         }
 361         cancel_lt->state |= BIT(ST_LT_CANCELLED);
 362         return 0;
 363 }
 364
 365 /*
 366  * Suspend the current lthread for specified time
 367  */
 368 void lthread_sleep(uint64_t nsecs)
 369 {
 370         struct lthread *lt = THIS_LTHREAD;
 371
 372         _lthread_sched_sleep(lt, nsecs);
 373
 374 }
 375
 376 /*
 377  * Suspend the current lthread for specified time
 378  */
 379 void lthread_sleep_clks(uint64_t clks)
 380 {
 381         struct lthread *lt = THIS_LTHREAD;
 382         uint64_t state = lt->state;
 383
 384         if (clks) {
 385                 _timer_start(lt, clks);
 386                 lt->state = state | BIT(ST_LT_SLEEPING);
 387         }
 388         DIAG_EVENT(lt, LT_DIAG_LTHREAD_SLEEP, clks, 0);
 389         _suspend();
 390 }
 391
 392 /*
 393  * Requeue the current thread to the back of the ready queue
 394  */
 395 void lthread_yield(void)
 396 {
 397         struct lthread *lt = THIS_LTHREAD;
 398
 399         DIAG_EVENT(lt, LT_DIAG_LTHREAD_YIELD, 0, 0);
 400
 401         _ready_queue_insert(THIS_SCHED, lt);
 402         ctx_switch(&(THIS_SCHED)->ctx, &lt->ctx);
 403 }
 404
 405 /*
 406  * Exit the current lthread
 407  * If a thread is joining pass the user pointer to it
 408  */
 409 void lthread_exit(void *ptr)
 410 {
 411         struct lthread *lt = THIS_LTHREAD;
 412
 413         /* if thread is detached (this is not valid) just exit */
 414         if (lt->state & BIT(ST_LT_DETACH))
 415                 return;
 416
 417         /* There is a race between lthread_join() and lthread_exit()
 418          *  - if exit before join then we suspend and resume on join
 419          *  - if join before exit then we resume the joining thread
 420          */
 421         if ((lt->join == LT_JOIN_INITIAL)
 422             && rte_atomic64_cmpset(&lt->join, LT_JOIN_INITIAL,
 423                                    LT_JOIN_EXITING)) {
 424
 425                 DIAG_EVENT(lt, LT_DIAG_LTHREAD_EXIT, 1, 0);
 426                 _suspend();
 427                 /* set the exit value */
 428                 if ((ptr != NULL) && (lt->lt_join->lt_exit_ptr != NULL))
 429                         *(lt->lt_join->lt_exit_ptr) = ptr;
 430
 431                 /* let the joining thread know we have set the exit value */
 432                 lt->join = LT_JOIN_EXIT_VAL_SET;
 433         } else {
 434
 435                 DIAG_EVENT(lt, LT_DIAG_LTHREAD_EXIT, 0, 0);
 436                 /* set the exit value */
 437                 if ((ptr != NULL) && (lt->lt_join->lt_exit_ptr != NULL))
 438                         *(lt->lt_join->lt_exit_ptr) = ptr;
 439                 /* let the joining thread know we have set the exit value */
 440                 lt->join = LT_JOIN_EXIT_VAL_SET;
 441                 _ready_queue_insert(lt->lt_join->sched,
 442                                     (struct lthread *)lt->lt_join);
 443         }
 444
 445
 446         /* wait until the joinging thread has collected the exit value */
 447         while (lt->join != LT_JOIN_EXIT_VAL_READ)
 448                 _reschedule();
 449
 450         /* reset join state */
 451         lt->join = LT_JOIN_INITIAL;
 452
 453         /* detach it so its resources can be released */
 454         lt->state |= (BIT(ST_LT_DETACH) | BIT(ST_LT_EXITED));
 455 }
 456
 457 /*
 458  * Join an lthread
 459  * Suspend until the joined thread returns
 460  */
 461 int lthread_join(struct lthread *lt, void **ptr)
 462 {
 463         if (lt == NULL)
 464                 return POSIX_ERRNO(EINVAL);
 465
 466         struct lthread *current = THIS_LTHREAD;
 467         uint64_t lt_state = lt->state;
 468
 469         /* invalid to join a detached thread, or a thread that is joined */
 470         if ((lt_state & BIT(ST_LT_DETACH)) || (lt->join == LT_JOIN_THREAD_SET))
 471                 return POSIX_ERRNO(EINVAL);
 472         /* pointer to the joining thread and a poingter to return a value */
 473         lt->lt_join = current;
 474         current->lt_exit_ptr = ptr;
 475         /* There is a race between lthread_join() and lthread_exit()
 476          *  - if join before exit we suspend and will resume when exit is called
 477          *  - if exit before join we resume the exiting thread
 478          */
 479         if ((lt->join == LT_JOIN_INITIAL)
 480             && rte_atomic64_cmpset(&lt->join, LT_JOIN_INITIAL,
 481                                    LT_JOIN_THREAD_SET)) {
 482
 483                 DIAG_EVENT(current, LT_DIAG_LTHREAD_JOIN, lt, 1);
 484                 _suspend();
 485         } else {
 486                 DIAG_EVENT(current, LT_DIAG_LTHREAD_JOIN, lt, 0);
 487                 _ready_queue_insert(lt->sched, lt);
 488         }
 489
 490         /* wait for exiting thread to set return value */
 491         while (lt->join != LT_JOIN_EXIT_VAL_SET)
 492                 _reschedule();
 493
 494         /* collect the return value */
 495         if (ptr != NULL)
 496                 *ptr = *current->lt_exit_ptr;
 497
 498         /* let the exiting thread proceed to exit */
 499         lt->join = LT_JOIN_EXIT_VAL_READ;
 500         return 0;
 501 }
 502
 503
 504 /*
 505  * Detach current lthread
 506  * A detached thread cannot be joined
 507  */
 508 void lthread_detach(void)
 509 {
 510         struct lthread *lt = THIS_LTHREAD;
 511
 512         DIAG_EVENT(lt, LT_DIAG_LTHREAD_DETACH, 0, 0);
 513
 514         uint64_t state = lt->state;
 515
 516         lt->state = state | BIT(ST_LT_DETACH);
 517 }
 518
 519 /*
 520  * Set function name of an lthread
 521  * this is a debug aid
 522  */
 523 void lthread_set_funcname(const char *f)
 524 {
 525         struct lthread *lt = THIS_LTHREAD;
 526
 527         strncpy(lt->funcname, f, sizeof(lt->funcname));
 528         lt->funcname[sizeof(lt->funcname)-1] = 0;
 529 }