Changeset 23 for trunk/kernel/syscalls/sys_thread_exit.c

Timestamp:

Jun 18, 2017, 10:06:41 PM (7 years ago)

Author:

alain

Message:

Introduce syscalls.

File:

• trunk/kernel/syscalls/sys_thread_exit.c (modified) (2 diffs)

trunk/kernel/syscalls/sys_thread_exit.c

@@ -1 +1 @@
 /*
- * kern/sys_thread_exit.c - terminates the execution of current thread
+ * sys_thread_exit.c - terminates the execution of current thread
  * 
- * Copyright (c) 2008,2009,2010,2011,2012 Ghassan Almaless
- * Copyright (c) 2011,2012 UPMC Sorbonne Universites
+ * Authors       Ghassan Almaless (2008,2009,2010,2011,2012)
+ *               Alain Greiner (2016,2017)
  *
- * This file is part of ALMOS-kernel.
+ * Copyright (c) UPMC Sorbonne Universites
  *
- * ALMOS-kernel is free software; you can redistribute it and/or modify it
+ * This file is part of ALMOS-MKH.
+ *
+ * ALMOS-MKH is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License as published by
  * the Free Software Foundation; version 2.0 of the License.
  *
- * ALMOS-kernel is distributed in the hope that it will be useful, but
+ * ALMOS-MKH is distributed in the hope that it will be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
@@ -17 +19 @@
  *
  * You should have received a copy of the GNU General Public License
- * along with ALMOS-kernel; if not, write to the Free Software Foundation,
+ * along with ALMOS-MKH; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#include <list.h>
+#include <hal_types.h>
+#include <hal_irqmask.h>
 #include <thread.h>
+#include <core.h>
 #include <scheduler.h>
-#include <wait_queue.h>
-#include <cluster.h>
-#include <dqdt.h>
-#include <process.h>
+#include <printk.h>
 
-///////////////////////////////////////
-int sys_thread_exit ( void * exit_val )
+
+////////////////////////////////////////
+int sys_thread_exit( void * exit_value )
 {
         thread_t  * this = CURRENT_THREAD;
     core_t    * core = this->core;
-        bool_t      isEmpty;
-        bool_t      isReleased;
     uint32_t    irq_state;
 
-        // update DQDT TODO must be done by thread destroy 
-        if(this->process->pid != 1) dqdt_local_update_threads( -1 );
+    // register the exit_value in thread descriptor
+    this->exit_value = exit_value;
 
-        spinlock_lock( &this->lock );
+    // we enter the join loop to wait the join
+    // only if thread is joinable
+    if( (this->flags & THREAD_FLAG_DETACHED) == 0 )
+    {
+            while( 1 ) 
+            {
+            // take the lock protecting the flags
+                remote_spinlock_lock( XPTR( local_cxy, &this->flags_lock ) );
 
-        if(!(thread_isJoinable(this)))
-        {
-                goto exit_dead;
+            // check the JOIN flag
+            if( this->flags & THREAD_FLAG_JOIN )       // parent made a join
+            {
+                // unblock the parent thread
+                thread_unblock( this->parent , THREAD_BLOCKED_JOIN );
+
+                // release the lock protecting the flags
+                    remote_spinlock_unlock( XPTR( local_cxy, &this->flags_lock ) );
+
+                // exit while
+                break;
+            }
+            else                                       // no join done by parent thread
+            {
+                // set the EXIT flag
+                this->flags |= THREAD_FLAG_EXIT;
+
+                // block this thread
+                thread_block( this , THREAD_BLOCKED_EXIT );
+
+                // release the lock protecting the flags
+                    remote_spinlock_unlock( XPTR( local_cxy, &this->flags_lock ) );
+
+                // deschedule
+                sched_yield();
+            }     
+        }
         }
-
-        // Check if there's a thread waiting the end of calling thread
-        isEmpty = wait_queue_isEmpty(&this->info.wait_queue);
-
-        if(isEmpty)
-        {
-                this->info.exit_value = exit_val;
-                wait_on(&this->info.wait_queue, WAIT_ANY);
-                spinlock_unlock_nosched(&this->lock);
-                sched_sleep(this);
-        }
-        else
-        {
-                this->info.join->info.exit_value = exit_val;
-                wakeup_one(&this->info.wait_queue, WAIT_ANY);
-                spinlock_unlock_nosched(&this->lock);
-        }
-
-exit_dead:
-
-        isReleased = false;
 
         // Release FPU if required
         hal_disable_irq( &irq_state );
-        if(core->fpu_owner == this)
-        {
-                core->fpu_owner = NULL;
-                isReleased = true;
-        }
+        if( core->fpu_owner == this )  core->fpu_owner = NULL;
         hal_restore_irq( irq_state );
 
-        if(isReleased)
-        {
-                thread_dmsg(1, "INFO: Thread %x has released FPU on CPU %d\n",
-                       this, 
-                       current_cpu->gid);
-        }
+        // suicide
+    thread_kill( this );
+        return 0;       
 
-        sched_exit(this);
-
-        PANIC ("Thread %x, CPU %d must never return", this, current_cpu->gid);
-        return -1;              /* Fake return ! */
-}
+}  // end sys_thread_exit()