src/gallium/drivers/llvmpipe/lp_cs_tpool.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2019 Red Hat.
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the "Software"),
   8  * to deal in the Software without restriction, including without limitation
   9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  10  * and/or sell copies of the Software, and to permit persons to whom the
  11  * Software is furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included
  14  * in all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  17  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  22  * SOFTWARE.
  23  *
  24  **************************************************************************/
  25
  26 /**
  27  * compute shader thread pool.
  28  * based on threadpool.c but modified heavily to be compute shader tuned.
  29  */
  30
  31 #include "util/u_thread.h"
  32 #include "util/u_memory.h"
  33 #include "lp_cs_tpool.h"
  34
  35 static int
  36 lp_cs_tpool_worker(void *data)
  37 {
  38    struct lp_cs_tpool *pool = data;
  39    struct lp_cs_local_mem lmem;
  40
  41    memset(&lmem, 0, sizeof(lmem));
  42    mtx_lock(&pool->m);
  43
  44    while (!pool->shutdown) {
  45       struct lp_cs_tpool_task *task;
  46
  47       while (list_empty(&pool->workqueue) && !pool->shutdown)
  48          cnd_wait(&pool->new_work, &pool->m);
  49
  50       if (pool->shutdown)
  51          break;
  52
  53       task = list_first_entry(&pool->workqueue, struct lp_cs_tpool_task,
  54                               list);
  55       unsigned this_iter = task->iter_start++;
  56
  57       if (task->iter_start == task->iter_total)
  58          list_del(&task->list);
  59
  60       mtx_unlock(&pool->m);
  61       task->work(task->data, this_iter, &lmem);
  62       mtx_lock(&pool->m);
  63       task->iter_finished++;
  64       if (task->iter_finished == task->iter_total)
  65          cnd_broadcast(&task->finish);
  66    }
  67    mtx_unlock(&pool->m);
  68    FREE(lmem.local_mem_ptr);
  69    return 0;
  70 }
  71
  72 struct lp_cs_tpool *
  73 lp_cs_tpool_create(unsigned num_threads)
  74 {
  75    struct lp_cs_tpool *pool = CALLOC_STRUCT(lp_cs_tpool);
  76
  77    if (!pool)
  78       return NULL;
  79
  80    (void) mtx_init(&pool->m, mtx_plain);
  81    cnd_init(&pool->new_work);
  82
  83    list_inithead(&pool->workqueue);
  84    assert (num_threads <= LP_MAX_THREADS);
  85    pool->num_threads = num_threads;
  86    for (unsigned i = 0; i < num_threads; i++)
  87       pool->threads[i] = u_thread_create(lp_cs_tpool_worker, pool);
  88    return pool;
  89 }
  90
  91 void
  92 lp_cs_tpool_destroy(struct lp_cs_tpool *pool)
  93 {
  94    if (!pool)
  95       return;
  96
  97    mtx_lock(&pool->m);
  98    pool->shutdown = true;
  99    cnd_broadcast(&pool->new_work);
 100    mtx_unlock(&pool->m);
 101
 102    for (unsigned i = 0; i < pool->num_threads; i++) {
 103       thrd_join(pool->threads[i], NULL);
 104    }
 105
 106    cnd_destroy(&pool->new_work);
 107    mtx_destroy(&pool->m);
 108    FREE(pool);
 109 }
 110
 111 struct lp_cs_tpool_task *
 112 lp_cs_tpool_queue_task(struct lp_cs_tpool *pool,
 113                        lp_cs_tpool_task_func work, void *data, int num_iters)
 114 {
 115    struct lp_cs_tpool_task *task;
 116
 117    if (pool->num_threads == 0) {
 118       struct lp_cs_local_mem lmem;
 119
 120       memset(&lmem, 0, sizeof(lmem));
 121       for (unsigned t = 0; t < num_iters; t++) {
 122          work(data, t, &lmem);
 123       }
 124       return NULL;
 125    }
 126    task = CALLOC_STRUCT(lp_cs_tpool_task);
 127    if (!task) {
 128       return NULL;
 129    }
 130
 131    task->work = work;
 132    task->data = data;
 133    task->iter_total = num_iters;
 134    cnd_init(&task->finish);
 135
 136    mtx_lock(&pool->m);
 137
 138    list_addtail(&task->list, &pool->workqueue);
 139
 140    cnd_signal(&pool->new_work);
 141    mtx_unlock(&pool->m);
 142    return task;
 143 }
 144
 145 void
 146 lp_cs_tpool_wait_for_task(struct lp_cs_tpool *pool,
 147                           struct lp_cs_tpool_task **task_handle)
 148 {
 149    struct lp_cs_tpool_task *task = *task_handle;
 150
 151    if (!pool || !task)
 152       return;
 153
 154    mtx_lock(&pool->m);
 155    while (task->iter_finished < task->iter_total)
 156       cnd_wait(&task->finish, &pool->m);
 157    mtx_unlock(&pool->m);
 158
 159    cnd_destroy(&task->finish);
 160    FREE(task);
 161    *task_handle = NULL;
 162 }