sys/contrib/openzfs/module/os/freebsd/spl/spl_taskq.c

   1 /*
   2  * Copyright (c) 2009 Pawel Jakub Dawidek <pjd@FreeBSD.org>
   3  * All rights reserved.
   4  *
   5  * Copyright (c) 2012 Spectra Logic Corporation.  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  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  */
  28
  29 #include <sys/cdefs.h>
  30 __FBSDID("$FreeBSD$");
  31
  32 #include <sys/types.h>
  33 #include <sys/param.h>
  34 #include <sys/kernel.h>
  35 #include <sys/kmem.h>
  36 #include <sys/lock.h>
  37 #include <sys/mutex.h>
  38 #include <sys/queue.h>
  39 #include <sys/taskqueue.h>
  40 #include <sys/taskq.h>
  41 #include <sys/zfs_context.h>
  42 #include <sys/ck.h>
  43 #include <sys/epoch.h>
  44
  45 #include <vm/uma.h>
  46
  47 #if __FreeBSD_version < 1201522
  48 #define taskqueue_start_threads_in_proc(tqp, count, pri, proc, name, ...) \
  49     taskqueue_start_threads(tqp, count, pri, name, __VA_ARGS__)
  50 #endif
  51
  52 static uint_t taskq_tsd;
  53 static uma_zone_t taskq_zone;
  54
  55 taskq_t *system_taskq = NULL;
  56 taskq_t *system_delay_taskq = NULL;
  57 taskq_t *dynamic_taskq = NULL;
  58
  59 proc_t *system_proc;
  60
  61 extern int uma_align_cache;
  62
  63 static MALLOC_DEFINE(M_TASKQ, "taskq", "taskq structures");
  64
  65 static CK_LIST_HEAD(tqenthashhead, taskq_ent) *tqenthashtbl;
  66 static unsigned long tqenthash;
  67 static unsigned long tqenthashlock;
  68 static struct sx *tqenthashtbl_lock;
  69
  70 static uint32_t tqidnext = 1;
  71
  72 #define TQIDHASH(tqid) (&tqenthashtbl[(tqid) & tqenthash])
  73 #define TQIDHASHLOCK(tqid) (&tqenthashtbl_lock[((tqid) & tqenthashlock)])
  74
  75 #define TIMEOUT_TASK 1
  76 #define NORMAL_TASK 2
  77
  78 static void
  79 system_taskq_init(void *arg)
  80 {
  81         int i;
  82
  83         tsd_create(&taskq_tsd, NULL);
  84         tqenthashtbl = hashinit(mp_ncpus * 8, M_TASKQ, &tqenthash);
  85         tqenthashlock = (tqenthash + 1) / 8;
  86         if (tqenthashlock > 0)
  87                 tqenthashlock--;
  88         tqenthashtbl_lock =
  89             malloc(sizeof (*tqenthashtbl_lock) * (tqenthashlock + 1),
  90             M_TASKQ, M_WAITOK | M_ZERO);
  91         for (i = 0; i < tqenthashlock + 1; i++)
  92                 sx_init_flags(&tqenthashtbl_lock[i], "tqenthash", SX_DUPOK);
  93         tqidnext = 1;
  94         taskq_zone = uma_zcreate("taskq_zone", sizeof (taskq_ent_t),
  95             NULL, NULL, NULL, NULL,
  96             UMA_ALIGN_CACHE, 0);
  97         system_taskq = taskq_create("system_taskq", mp_ncpus, minclsyspri,
  98             0, 0, 0);
  99         system_delay_taskq = taskq_create("system_delay_taskq", mp_ncpus,
 100             minclsyspri, 0, 0, 0);
 101 }
 102 SYSINIT(system_taskq_init, SI_SUB_CONFIGURE, SI_ORDER_ANY, system_taskq_init,
 103     NULL);
 104
 105 static void
 106 system_taskq_fini(void *arg)
 107 {
 108         int i;
 109
 110         taskq_destroy(system_delay_taskq);
 111         taskq_destroy(system_taskq);
 112         uma_zdestroy(taskq_zone);
 113         tsd_destroy(&taskq_tsd);
 114         for (i = 0; i < tqenthashlock + 1; i++)
 115                 sx_destroy(&tqenthashtbl_lock[i]);
 116         for (i = 0; i < tqenthash + 1; i++)
 117                 VERIFY(CK_LIST_EMPTY(&tqenthashtbl[i]));
 118         free(tqenthashtbl_lock, M_TASKQ);
 119         free(tqenthashtbl, M_TASKQ);
 120 }
 121 SYSUNINIT(system_taskq_fini, SI_SUB_CONFIGURE, SI_ORDER_ANY, system_taskq_fini,
 122     NULL);
 123
 124 static taskq_ent_t *
 125 taskq_lookup(taskqid_t tqid)
 126 {
 127         taskq_ent_t *ent = NULL;
 128
 129         sx_xlock(TQIDHASHLOCK(tqid));
 130         CK_LIST_FOREACH(ent, TQIDHASH(tqid), tqent_hash) {
 131                 if (ent->tqent_id == tqid)
 132                         break;
 133         }
 134         if (ent != NULL)
 135                 refcount_acquire(&ent->tqent_rc);
 136         sx_xunlock(TQIDHASHLOCK(tqid));
 137         return (ent);
 138 }
 139
 140 static taskqid_t
 141 taskq_insert(taskq_ent_t *ent)
 142 {
 143         taskqid_t tqid = atomic_fetchadd_int(&tqidnext, 1);
 144
 145         ent->tqent_id = tqid;
 146         ent->tqent_registered = B_TRUE;
 147         sx_xlock(TQIDHASHLOCK(tqid));
 148         CK_LIST_INSERT_HEAD(TQIDHASH(tqid), ent, tqent_hash);
 149         sx_xunlock(TQIDHASHLOCK(tqid));
 150         return (tqid);
 151 }
 152
 153 static void
 154 taskq_remove(taskq_ent_t *ent)
 155 {
 156         taskqid_t tqid = ent->tqent_id;
 157
 158         if (!ent->tqent_registered)
 159                 return;
 160
 161         sx_xlock(TQIDHASHLOCK(tqid));
 162         CK_LIST_REMOVE(ent, tqent_hash);
 163         sx_xunlock(TQIDHASHLOCK(tqid));
 164         ent->tqent_registered = B_FALSE;
 165 }
 166
 167 static void
 168 taskq_tsd_set(void *context)
 169 {
 170         taskq_t *tq = context;
 171
 172 #if defined(__amd64__) || defined(__i386__) || defined(__aarch64__)
 173         if (context != NULL && tsd_get(taskq_tsd) == NULL)
 174                 fpu_kern_thread(FPU_KERN_NORMAL);
 175 #endif
 176         tsd_set(taskq_tsd, tq);
 177 }
 178
 179 static taskq_t *
 180 taskq_create_impl(const char *name, int nthreads, pri_t pri,
 181     proc_t *proc __maybe_unused, uint_t flags)
 182 {
 183         taskq_t *tq;
 184
 185         if ((flags & TASKQ_THREADS_CPU_PCT) != 0)
 186                 nthreads = MAX((mp_ncpus * nthreads) / 100, 1);
 187
 188         tq = kmem_alloc(sizeof (*tq), KM_SLEEP);
 189         tq->tq_queue = taskqueue_create(name, M_WAITOK,
 190             taskqueue_thread_enqueue, &tq->tq_queue);
 191         taskqueue_set_callback(tq->tq_queue, TASKQUEUE_CALLBACK_TYPE_INIT,
 192             taskq_tsd_set, tq);
 193         taskqueue_set_callback(tq->tq_queue, TASKQUEUE_CALLBACK_TYPE_SHUTDOWN,
 194             taskq_tsd_set, NULL);
 195         (void) taskqueue_start_threads_in_proc(&tq->tq_queue, nthreads, pri,
 196             proc, "%s", name);
 197
 198         return ((taskq_t *)tq);
 199 }
 200
 201 taskq_t *
 202 taskq_create(const char *name, int nthreads, pri_t pri, int minalloc __unused,
 203     int maxalloc __unused, uint_t flags)
 204 {
 205         return (taskq_create_impl(name, nthreads, pri, system_proc, flags));
 206 }
 207
 208 taskq_t *
 209 taskq_create_proc(const char *name, int nthreads, pri_t pri,
 210     int minalloc __unused, int maxalloc __unused, proc_t *proc, uint_t flags)
 211 {
 212         return (taskq_create_impl(name, nthreads, pri, proc, flags));
 213 }
 214
 215 void
 216 taskq_destroy(taskq_t *tq)
 217 {
 218
 219         taskqueue_free(tq->tq_queue);
 220         kmem_free(tq, sizeof (*tq));
 221 }
 222
 223 int
 224 taskq_member(taskq_t *tq, kthread_t *thread)
 225 {
 226
 227         return (taskqueue_member(tq->tq_queue, thread));
 228 }
 229
 230 taskq_t *
 231 taskq_of_curthread(void)
 232 {
 233         return (tsd_get(taskq_tsd));
 234 }
 235
 236 static void
 237 taskq_free(taskq_ent_t *task)
 238 {
 239         taskq_remove(task);
 240         if (refcount_release(&task->tqent_rc))
 241                 uma_zfree(taskq_zone, task);
 242 }
 243
 244 int
 245 taskq_cancel_id(taskq_t *tq, taskqid_t tid)
 246 {
 247         uint32_t pend;
 248         int rc;
 249         taskq_ent_t *ent;
 250
 251         if (tid == 0)
 252                 return (0);
 253
 254         if ((ent = taskq_lookup(tid)) == NULL)
 255                 return (0);
 256
 257         ent->tqent_cancelled = B_TRUE;
 258         if (ent->tqent_type == TIMEOUT_TASK) {
 259                 rc = taskqueue_cancel_timeout(tq->tq_queue,
 260                     &ent->tqent_timeout_task, &pend);
 261         } else
 262                 rc = taskqueue_cancel(tq->tq_queue, &ent->tqent_task, &pend);
 263         if (rc == EBUSY) {
 264                 taskqueue_drain(tq->tq_queue, &ent->tqent_task);
 265         } else if (pend) {
 266                 /*
 267                  * Tasks normally free themselves when run, but here the task
 268                  * was cancelled so it did not free itself.
 269                  */
 270                 taskq_free(ent);
 271         }
 272         /* Free the extra reference we added with taskq_lookup. */
 273         taskq_free(ent);
 274         return (rc);
 275 }
 276
 277 static void
 278 taskq_run(void *arg, int pending __unused)
 279 {
 280         taskq_ent_t *task = arg;
 281
 282         if (!task->tqent_cancelled)
 283                 task->tqent_func(task->tqent_arg);
 284         taskq_free(task);
 285 }
 286
 287 taskqid_t
 288 taskq_dispatch_delay(taskq_t *tq, task_func_t func, void *arg,
 289     uint_t flags, clock_t expire_time)
 290 {
 291         taskq_ent_t *task;
 292         taskqid_t tid;
 293         clock_t timo;
 294         int mflag;
 295
 296         timo = expire_time - ddi_get_lbolt();
 297         if (timo <= 0)
 298                 return (taskq_dispatch(tq, func, arg, flags));
 299
 300         if ((flags & (TQ_SLEEP | TQ_NOQUEUE)) == TQ_SLEEP)
 301                 mflag = M_WAITOK;
 302         else
 303                 mflag = M_NOWAIT;
 304
 305         task = uma_zalloc(taskq_zone, mflag);
 306         if (task == NULL)
 307                 return (0);
 308         task->tqent_func = func;
 309         task->tqent_arg = arg;
 310         task->tqent_type = TIMEOUT_TASK;
 311         task->tqent_cancelled = B_FALSE;
 312         refcount_init(&task->tqent_rc, 1);
 313         tid = taskq_insert(task);
 314         TIMEOUT_TASK_INIT(tq->tq_queue, &task->tqent_timeout_task, 0,
 315             taskq_run, task);
 316
 317         taskqueue_enqueue_timeout(tq->tq_queue, &task->tqent_timeout_task,
 318             timo);
 319         return (tid);
 320 }
 321
 322 taskqid_t
 323 taskq_dispatch(taskq_t *tq, task_func_t func, void *arg, uint_t flags)
 324 {
 325         taskq_ent_t *task;
 326         int mflag, prio;
 327         taskqid_t tid;
 328
 329         if ((flags & (TQ_SLEEP | TQ_NOQUEUE)) == TQ_SLEEP)
 330                 mflag = M_WAITOK;
 331         else
 332                 mflag = M_NOWAIT;
 333         /*
 334          * If TQ_FRONT is given, we want higher priority for this task, so it
 335          * can go at the front of the queue.
 336          */
 337         prio = !!(flags & TQ_FRONT);
 338
 339         task = uma_zalloc(taskq_zone, mflag);
 340         if (task == NULL)
 341                 return (0);
 342         refcount_init(&task->tqent_rc, 1);
 343         task->tqent_func = func;
 344         task->tqent_arg = arg;
 345         task->tqent_cancelled = B_FALSE;
 346         task->tqent_type = NORMAL_TASK;
 347         tid = taskq_insert(task);
 348         TASK_INIT(&task->tqent_task, prio, taskq_run, task);
 349         taskqueue_enqueue(tq->tq_queue, &task->tqent_task);
 350         VERIFY(tid);
 351         return (tid);
 352 }
 353
 354 static void
 355 taskq_run_ent(void *arg, int pending __unused)
 356 {
 357         taskq_ent_t *task = arg;
 358
 359         task->tqent_func(task->tqent_arg);
 360 }
 361
 362 void
 363 taskq_dispatch_ent(taskq_t *tq, task_func_t func, void *arg, uint32_t flags,
 364     taskq_ent_t *task)
 365 {
 366         int prio;
 367
 368         /*
 369          * If TQ_FRONT is given, we want higher priority for this task, so it
 370          * can go at the front of the queue.
 371          */
 372         prio = !!(flags & TQ_FRONT);
 373         task->tqent_cancelled = B_FALSE;
 374         task->tqent_registered = B_FALSE;
 375         task->tqent_id = 0;
 376         task->tqent_func = func;
 377         task->tqent_arg = arg;
 378
 379         TASK_INIT(&task->tqent_task, prio, taskq_run_ent, task);
 380         taskqueue_enqueue(tq->tq_queue, &task->tqent_task);
 381 }
 382
 383 void
 384 taskq_wait(taskq_t *tq)
 385 {
 386         taskqueue_quiesce(tq->tq_queue);
 387 }
 388
 389 void
 390 taskq_wait_id(taskq_t *tq, taskqid_t tid)
 391 {
 392         taskq_ent_t *ent;
 393
 394         if (tid == 0)
 395                 return;
 396         if ((ent = taskq_lookup(tid)) == NULL)
 397                 return;
 398
 399         taskqueue_drain(tq->tq_queue, &ent->tqent_task);
 400         taskq_free(ent);
 401 }
 402
 403 void
 404 taskq_wait_outstanding(taskq_t *tq, taskqid_t id __unused)
 405 {
 406         taskqueue_drain_all(tq->tq_queue);
 407 }
 408
 409 int
 410 taskq_empty_ent(taskq_ent_t *t)
 411 {
 412         return (t->tqent_task.ta_pending == 0);
 413 }