X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=rts%2FTask.c;h=9397789105a98fee351e98b9c717605ecace095c;hb=3710a4ef1ca665fe4ed705a6b0f4400d680c7b54;hp=992360988464b957e07961e89db41f96a2d166f7;hpb=a91cc8496bf4ea7fe1e3ad9d97836152f3939ffa;p=ghc-hetmet.git

diff --git a/rts/Task.c b/rts/Task.c
index 9923609..9397789 100644
--- a/rts/Task.c
+++ b/rts/Task.c
@@ -15,8 +15,10 @@
 #include "Capability.h"
 #include "Stats.h"
 #include "RtsFlags.h"
+#include "Storage.h"
 #include "Schedule.h"
 #include "Hash.h"
+#include "Trace.h"
 
 #if HAVE_SIGNAL_H
 #include <signal.h>
@@ -27,8 +29,6 @@
 Task *all_tasks = NULL;
 static Task *task_free_list = NULL; // singly-linked
 static nat taskCount;
-#define DEFAULT_MAX_WORKERS 64
-static nat maxWorkers; // we won't create more workers than this
 static nat tasksRunning;
 static nat workerCount;
 
@@ -57,7 +57,6 @@ initTaskManager (void)
 	taskCount = 0;
 	workerCount = 0;
 	tasksRunning = 0;
-	maxWorkers = DEFAULT_MAX_WORKERS;
 	initialized = 1;
 #if defined(THREADED_RTS)
 	newThreadLocalKey(&currentTaskKey);
@@ -65,11 +64,37 @@ initTaskManager (void)
     }
 }
 
-
-void
-stopTaskManager (void)
+nat
+freeTaskManager (void)
 {
-    IF_DEBUG(scheduler, sched_belch("stopping task manager, %d tasks still running", tasksRunning));
+    Task *task, *next;
+
+    ASSERT_LOCK_HELD(&sched_mutex);
+
+    debugTrace(DEBUG_sched, "freeing task manager, %d tasks still running",
+               tasksRunning);
+
+    for (task = all_tasks; task != NULL; task = next) {
+        next = task->all_link;
+        if (task->stopped) {
+            // We only free resources if the Task is not in use.  A
+            // Task may still be in use if we have a Haskell thread in
+            // a foreign call while we are attempting to shut down the
+            // RTS (see conc059).
+#if defined(THREADED_RTS)
+            closeCondition(&task->cond);
+            closeMutex(&task->lock);
+#endif
+            stgFree(task);
+        }
+    }
+    all_tasks = NULL;
+    task_free_list = NULL;
+#if defined(THREADED_RTS)
+    freeThreadLocalKey(&currentTaskKey);
+#endif
+
+    return tasksRunning;
 }
 
 
@@ -81,7 +106,8 @@ newTask (void)
 #endif
     Task *task;
 
-    task = stgMallocBytes(sizeof(Task), "newTask");
+#define ROUND_TO_CACHE_LINE(x) ((((x)+63) / 64) * 64)
+    task = stgMallocBytes(ROUND_TO_CACHE_LINE(sizeof(Task)), "newTask");
     
     task->cap  = NULL;
     task->stopped = rtsFalse;
@@ -115,7 +141,6 @@ newTask (void)
     all_tasks = task;
 
     taskCount++;
-    workerCount++;
 
     return task;
 }
@@ -144,13 +169,14 @@ newBoundTask (void)
 
     taskEnter(task);
 
-    IF_DEBUG(scheduler,sched_belch("new task (taskCount: %d)", taskCount););
+    debugTrace(DEBUG_sched, "new task (taskCount: %d)", taskCount);
     return task;
 }
 
 void
 boundTaskExiting (Task *task)
 {
+    task->tso = NULL;
     task->stopped = rtsTrue;
     task->cap = NULL;
 
@@ -168,7 +194,7 @@ boundTaskExiting (Task *task)
     task_free_list = task;
     RELEASE_LOCK(&sched_mutex);
 
-    IF_DEBUG(scheduler,sched_belch("task exiting"));
+    debugTrace(DEBUG_sched, "task exiting");
 }
 
 #ifdef THREADED_RTS
@@ -182,9 +208,13 @@ discardTask (Task *task)
 {
     ASSERT_LOCK_HELD(&sched_mutex);
     if (!task->stopped) {
-	IF_DEBUG(scheduler,sched_belch("discarding task %p", TASK_ID(task)));
+	debugTrace(DEBUG_sched, "discarding task %ld", (long)TASK_ID(task));
 	task->cap = NULL;
-	task->tso = NULL;
+        if (task->tso == NULL) {
+            workerCount--;
+        } else {
+            task->tso = NULL;
+        }
 	task->stopped = rtsTrue;
 	tasksRunning--;
 	task->next = task_free_list;
@@ -225,15 +255,22 @@ workerTaskStop (Task *task)
     ASSERT(myTask() == task);
 #endif
 
+    task->cap = NULL;
     taskTimeStamp(task);
     task->stopped = rtsTrue;
     tasksRunning--;
+    workerCount--;
+
+    ACQUIRE_LOCK(&sched_mutex);
+    task->next = task_free_list;
+    task_free_list = task;
+    RELEASE_LOCK(&sched_mutex);
 }
 
 void
 resetTaskManagerAfterFork (void)
 {
-#warning TODO!
+    // TODO!
     taskCount = 0;
 }
 
@@ -247,9 +284,6 @@ startWorkerTask (Capability *cap,
   OSThreadId tid;
   Task *task;
 
-  if (workerCount >= maxWorkers) {
-      barf("too many workers; runaway worker creation?");
-  }
   workerCount++;
 
   // A worker always gets a fresh Task structure.
@@ -272,10 +306,11 @@ startWorkerTask (Capability *cap,
 
   r = createOSThread(&tid, (OSThreadProc *)taskStart, task);
   if (r != 0) {
-    barf("startTask: Can't create new task");
+    sysErrorBelch("failed to create OS thread");
+    stg_exit(EXIT_FAILURE);
   }
 
-  IF_DEBUG(scheduler,sched_belch("new worker task (taskCount: %d)", taskCount););
+  debugTrace(DEBUG_sched, "new worker task (taskCount: %d)", taskCount);
 
   task->id = tid;
 
@@ -309,7 +344,7 @@ printAllTasks(void)
 		debugBelch("on capability %d, ", task->cap->no);
 	    }
 	    if (task->tso) {
-		debugBelch("bound to thread %d", task->tso->id);
+	      debugBelch("bound to thread %lu", (unsigned long)task->tso->id);
 	    } else {
 		debugBelch("worker");
 	    }