Changeset c713aa56 in mainline

Timestamp:

2010-01-30T15:31:59Z (15 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

89ee7ff

Parents:

e7aa9f4

Message:

Do not deadlock when the task cleans up messages it sent itself.

File:

• kernel/generic/src/ipc/ipc.c (modified) (6 diffs)

kernel/generic/src/ipc/ipc.c

@@ -212 +212 @@
  *
  * @param call          Call structure to be answered.
- */
-static void _ipc_answer_free_call(call_t *call)
+ * @param selflocked    If true, then TASK->answebox is locked.
+ */
+static void _ipc_answer_free_call(call_t *call, bool selflocked)
 {
         answerbox_t *callerbox = call->callerbox;
+        bool do_lock = ((!selflocked) || callerbox != (&TASK->answerbox));
 
         call->flags |= IPC_CALL_ANSWERED;
@@ -226 +228 @@
         }
 
-        spinlock_lock(&callerbox->lock);
+        if (do_lock)
+                spinlock_lock(&callerbox->lock);
         list_append(&call->link, &callerbox->answers);
-        spinlock_unlock(&callerbox->lock);
+        if (do_lock)
+                spinlock_unlock(&callerbox->lock);
         waitq_wakeup(&callerbox->wq, WAKEUP_FIRST);
 }
@@ -244 +248 @@
         spinlock_unlock(&box->lock);
         /* Send back answer */
-        _ipc_answer_free_call(call);
+        _ipc_answer_free_call(call, false);
 }
 
@@ -261 +265 @@
         atomic_inc(&phone->active_calls);
         IPC_SET_RETVAL(call->data, err);
-        _ipc_answer_free_call(call);
+        _ipc_answer_free_call(call, false);
 }
 
@@ -300 +304 @@
                 if (call->flags & IPC_CALL_FORWARDED) {
                         IPC_SET_RETVAL(call->data, EFORWARD);
-                        _ipc_answer_free_call(call);
+                        _ipc_answer_free_call(call, false);
                 } else {
                         if (phone->state == IPC_PHONE_HUNGUP)
@@ -455 +459 @@
 
                 IPC_SET_RETVAL(call->data, EHANGUP);
-                _ipc_answer_free_call(call);
+                _ipc_answer_free_call(call, true);
         }
 }