WebSVN – HelenOS-historic – Diff – /kernel/trunk/generic/src/ipc/ipc.c

 /* Lock ordering
+ *
  * First the answerbox, then the phone
  */
+#include <synch/condvar.h>
-#include <synch/waitq.h>
+#include <synch/mutex.h>
 #include <ipc/ipc.h>
 #include <errno.h>
 #include <mm/slab.h>
 #include <arch.h>
 #include <proc/task.h>
 #include <debug.h>
 #include <print.h>
 #include <proc/thread.h>
+/* Open channel that is assigned automatically to new tasks */
-answerbox_t *ipc_central_box;
+answerbox_t *ipc_phone_0 = NULL;
 static slab_cache_t *ipc_call_slab;
 /** Allocate & initialize call structure
+ *
     call->callerbox = &TASK->answerbox;
     return call;
+}
+/** Initialize allocated call */
+void ipc_call_init(call_t *call)
+{
+    call->callerbox = &TASK->answerbox;
+    call->flags = IPC_CALL_STATIC_ALLOC;
+}
 /** Deallocate call stracuture */
 void ipc_call_free(call_t *call)
+{
     slab_free(ipc_call_slab, call);
+}
 /** Initialize answerbox structure
  */
 void ipc_answerbox_init(answerbox_t *box)
+{
-    spinlock_initialize(&box->lock, "abox_lock");
+    mutex_initialize(&box->mutex);
-    waitq_initialize(&box->wq);
+    condvar_initialize(&box->cv);
     list_initialize(&box->connected_phones);
     list_initialize(&box->calls);
     list_initialize(&box->dispatched_calls);
     list_initialize(&box->answers);
+}
 void ipc_phone_init(phone_t *phone, answerbox_t *box)
+{
     spinlock_initialize(&phone->lock, "phone_lock");
     phone->callee = box;
-    spinlock_lock(&box->lock);
+    mutex_lock(&box->mutex);
     list_append(&phone->list, &box->connected_phones);
-    spinlock_unlock(&box->lock);
+    mutex_unlock(&box->mutex);
+}
 /** Disconnect phone from answerbox */
 void ipc_phone_destroy(phone_t *phone)
+{
     answerbox_t *box = phone->callee;
     ASSERT(box);
-    spinlock_lock(&box->lock);
+    mutex_lock(&box->mutex);
     list_remove(&phone->list);
-    spinlock_unlock(&box->lock);
+    mutex_unlock(&box->mutex);
+}
 /** Helper function to facilitate synchronous calls */
 void ipc_call_sync(phone_t *phone, call_t *request)
+{
+{
     answerbox_t *box = phone->callee;
     ASSERT(box);
-    spinlock_lock(&box->lock);
+    mutex_lock(&box->mutex);
     list_append(&request->list, &box->calls);
-    spinlock_unlock(&box->lock);
+    mutex_unlock(&box->mutex);
-    waitq_wakeup(&box->wq, 0);
+    condvar_signal(&box->cv);
+}
 /** Answer message back to phone
+ *
  * @param box Answerbox that is answering the message
+{
     answerbox_t *callerbox = request->callerbox;
     request->flags |= IPC_CALL_ANSWERED;
-    spinlock_lock(&box->lock);
+    mutex_lock(&box->mutex);
-    spinlock_lock(&callerbox->lock);
     list_remove(&request->list);
-    list_append(&request->list, &callerbox->answers);
-    waitq_wakeup(&callerbox->wq, 0);
+    mutex_unlock(&box->mutex);
-    spinlock_unlock(&callerbox->lock);
+    mutex_lock(&callerbox->mutex);
+    list_append(&request->list, &callerbox->answers);
-    spinlock_unlock(&box->lock);
+    mutex_unlock(&callerbox->mutex);
+    condvar_signal(&callerbox->cv);
+}
 /** Wait for phone call
+ *
  * @return Recived message address
  */
 call_t * ipc_wait_for_call(answerbox_t *box, int flags)
+{
     call_t *request;
-    if ((flags & IPC_WAIT_NONBLOCKING)) {
+    mutex_lock(&box->mutex);
-        if (waitq_sleep_timeout(&box->wq,SYNCH_NO_TIMEOUT,SYNCH_NON_BLOCKING) == ESYNCH_WOULD_BLOCK)
-            return 0;
+    while (1) {
-    } else {
-        waitq_sleep(&box->wq);
+        if (!list_empty(&box->answers)) {
-    }
-    // TODO - might need condition variable+mutex if we want to support
-    // removing of requests from queue before dispatch
-    spinlock_lock(&box->lock);
-    /* Handle answers first */
+            /* Handle asynchronous answers */
-    if (!list_empty(&box->answers)) {
-        request = list_get_instance(box->answers.next, call_t, list);
+            request = list_get_instance(box->answers.next, call_t, list);
-        list_remove(&request->list);
+            list_remove(&request->list);
-    } else {
-        ASSERT (! list_empty(&box->calls));
+        } else if (!list_empty(&box->calls)) {
+            /* Handle requests */
-        request = list_get_instance(box->calls.next, call_t, list);
+            request = list_get_instance(box->calls.next, call_t, list);
-        list_remove(&request->list);
+            list_remove(&request->list);
-        /* Append request to dispatch queue */
+            /* Append request to dispatch queue */
-        list_append(&request->list, &box->dispatched_calls);
+            list_append(&request->list, &box->dispatched_calls);
+        } else {
+            if (!(flags & IPC_WAIT_NONBLOCKING)) {
+                condvar_wait(&box->cv, &box->mutex);
+                continue;
+            }
+            if (condvar_trywait(&box->cv, &box->mutex) != ESYNCH_WOULD_BLOCK)
+                continue;
+            request = NULL;
+        }
+        break;
+    }
-    spinlock_unlock(&box->lock);
+    mutex_unlock(&box->mutex);
     return request;
+}
 /** Initilize ipc subsystem */
 void ipc_init(void)
     ipc_call_slab = slab_cache_create("ipc_call",
                       sizeof(call_t),
 ,
                       NULL, NULL, 0);
+}
-static void ipc_phonecompany_thread(void *data)
-{
-    call_t *call;
-    printf("Phone company started.\n");
-    while (1) {
-        call = ipc_wait_for_call(&TASK->answerbox, 0);
-        printf("Received phone call - %P %P\n",
-               call->data[0], call->data[1]);
-        call->data[0] = 0xbabaaaee;;
-        call->data[1] = 0xaaaaeeee;
-        ipc_answer(&TASK->answerbox, call);
-        printf("Call answered.\n");
-    }
-}
-void ipc_create_phonecompany(void)
-{
-    thread_t *t;
-    if ((t = thread_create(ipc_phonecompany_thread, "phonecompany",
-                   TASK, 0)))
-        thread_ready(t);
-    else
-        panic("thread_create/phonecompany");
-    ipc_central_box = &TASK->answerbox;
-}

Subversion Repositories HelenOS-historic

(root)/kernel/trunk/generic/src/ipc/ipc.c – Rev 959 → 965