ThreadPool

Change-Id: I09bf867a2dbb45e063e4785f5b2b1f705fae72c8
Reviewed-on: http://gfw160.austin.ibm.com:8080/gerrit/680
Tested-by: Jenkins Server
Reviewed-by: Douglas R. Gilbert <dgilbert@us.ibm.com>
Reviewed-by: Bradley W. Bishop <bradleyb@us.ibm.com>
Reviewed-by: Terry J. Opie <opiet@us.ibm.com>
Reviewed-by: MIKE J. JONES <mjjones@us.ibm.com>
Reviewed-by: A. Patrick Williams III <iawillia@us.ibm.com>

1 files changed, 123 insertions, 0 deletions

diff --git a/src/usr/util/threadpool.C b/src/usr/util/threadpool.C
new file mode 100644
index 000000000..e11d8807b
--- /dev/null
+++ b/src/usr/util/threadpool.C
@@ -0,0 +1,123 @@
+//  IBM_PROLOG_BEGIN_TAG
+//  This is an automatically generated prolog.
+//
+//  $Source: src/usr/util/threadpool.C $
+//
+//  IBM CONFIDENTIAL
+//
+//  COPYRIGHT International Business Machines Corp. 2012
+//
+//  p1
+//
+//  Object Code Only (OCO) source materials
+//  Licensed Internal Code Source Materials
+//  IBM HostBoot Licensed Internal Code
+//
+//  The source code for this program is not published or other-
+//  wise divested of its trade secrets, irrespective of what has
+//  been deposited with the U.S. Copyright Office.
+//
+//  Origin: 30
+//
+//  IBM_PROLOG_END
+#include <util/threadpool.H>
+#include <sys/task.h>
+#include <sys/misc.h>
+
+void Util::__Util_ThreadPool_Impl::ThreadPoolImpl::__init()
+{
+    // Initialize all member variables.
+    iv_worklist.clear();
+    mutex_init(&iv_mutex);
+    sync_cond_init(&iv_condvar);
+    iv_children.clear();
+    iv_shutdown = false;
+}
+
+void Util::__Util_ThreadPool_Impl::ThreadPoolImpl::__insert(void* i_workItem)
+{
+    mutex_lock(&iv_mutex);
+
+    // Insert item on to the work list and signal any worker thread that may
+    // be waiting.
+    iv_worklist.push_back(i_workItem);
+    sync_cond_signal(&iv_condvar);
+
+    mutex_unlock(&iv_mutex);
+}
+
+void* Util::__Util_ThreadPool_Impl::ThreadPoolImpl::__remove(order_fn_t fn)
+{
+    void* val = NULL;
+
+    mutex_lock(&iv_mutex);
+    do
+    {
+        // Wait until the worklist is empty or told to shutdown.
+        while(iv_worklist.empty() && !iv_shutdown)
+        {
+            sync_cond_wait(&iv_condvar, &iv_mutex);
+        }
+
+        // If told to shutdown and no work remains, end thread.
+        if (iv_worklist.empty() && iv_shutdown)
+        {
+            break;
+        }
+
+        // Otherwise, obtain next item from worklist, using order function
+        // passed to us.
+        worklist_itr_t itr = fn(iv_worklist.begin(), iv_worklist.end());
+
+        val = *itr;
+        iv_worklist.erase(itr);
+
+    } while(0);
+
+    mutex_unlock(&iv_mutex);
+
+    return val;
+}
+
+void Util::__Util_ThreadPool_Impl::ThreadPoolImpl::__start(
+        Util::__Util_ThreadPool_Impl::ThreadPoolImpl::start_fn_t fn,
+        void* instance)
+{
+    mutex_lock(&iv_mutex);
+
+    size_t thread_count = Util::ThreadPoolManager::getThreadCount();
+    while(thread_count--)
+    {
+        // Create children and add to a queue for later joining (during
+        // shutdown)
+        iv_children.push_back(task_create(fn, instance));
+    }
+
+    mutex_unlock(&iv_mutex);
+}
+
+void Util::__Util_ThreadPool_Impl::ThreadPoolImpl::__shutdown()
+{
+    mutex_lock(&iv_mutex);
+
+    // Set shutdown status and signal all children to release from their
+    // condition variable.
+    iv_shutdown = true;
+    sync_cond_broadcast(&iv_condvar);
+
+    // Join on all the children.
+    while(!iv_children.empty())
+    {
+        tid_t child = iv_children.front();
+        iv_children.pop_front();
+
+        mutex_unlock(&iv_mutex);
+        task_wait_tid(child, NULL, NULL);  // Don't need status.
+        mutex_lock(&iv_mutex);
+    }
+
+    mutex_unlock(&iv_mutex);
+}
+
+// Default thread count of one per HW thread.
+size_t Util::ThreadPoolManager::cv_size = cpu_thread_count();