git.cworth.org Git - apitrace/blob - common/workqueue_posix.cpp

   1 #include <pthread.h>
   2 #include <queue>
   3 #include <assert.h>
   4
   5 #include "os_workqueue.hpp"
   6
   7 namespace os
   8 {
   9
  10 /**
  11  * return 0 on batch complete, -1 on thread exit request.
  12  */
  13 int WorkQueue::run_tasks(void)
  14 {
  15     os::unique_lock<os::mutex> lock(mutex);
  16
  17     while (work_queue.empty() && !exit_workqueue) {
  18         wake_cond.wait(lock);
  19     }
  20
  21     if (exit_workqueue) {
  22         return -1;
  23     }
  24
  25     std::queue<WorkQueueWork *> batch;
  26     std::swap(work_queue, batch);
  27     busy = true;
  28
  29     lock.unlock();
  30
  31     assert(!batch.empty());
  32     while (!batch.empty()) {
  33         WorkQueueWork *task;
  34
  35         task = batch.front();
  36         task->run();
  37         batch.pop();
  38         delete task;
  39     }
  40
  41     lock.lock();
  42
  43     busy = false;
  44     complete_cond.signal();
  45
  46     return 0;
  47 }
  48
  49 /* Must be called with WorkQueue::lock held */
  50 void WorkQueue::wake_up_thread(void)
  51 {
  52     wake_cond.signal();
  53 }
  54
  55 void WorkQueue::queue_work(WorkQueueWork *task)
  56 {
  57     mutex.lock();
  58     work_queue.push(task);
  59     wake_up_thread();
  60     mutex.unlock();
  61 }
  62
  63 void WorkQueue::flush(void)
  64 {
  65     os::unique_lock<os::mutex> lock(mutex);
  66     while (!work_queue.empty() || busy) {
  67         complete_cond.wait(lock);
  68     }
  69 }
  70
  71 void WorkQueue::thread_entry(void)
  72 {
  73     int err;
  74
  75     do {
  76         err = run_tasks();
  77     } while (!err);
  78 }
  79
  80 void WorkQueue::destroy(void)
  81 {
  82     mutex.lock();
  83     exit_workqueue = true;
  84     wake_up_thread();
  85     mutex.unlock();
  86 }
  87
  88 extern "C"
  89 void *WorkQueue__entry_thunk(void *data)
  90 {
  91     WorkQueue *thread = static_cast<WorkQueue *>(data);
  92
  93     thread->thread_entry();
  94
  95     return NULL;
  96 }
  97
  98 WorkQueue::WorkQueue(void) :
  99     busy(false), exit_workqueue(false)
 100 {
 101     int err;
 102
 103     err = pthread_create(&handle, NULL, WorkQueue__entry_thunk, this);
 104     assert(!err);
 105 }
 106
 107 WorkQueue::~WorkQueue(void)
 108 {
 109     pthread_join(handle, NULL);
 110 }
 111
 112 }