Changeset 651 for trunk/kernel/syscalls/sys_thread_exit.c

Timestamp:

Nov 14, 2019, 11:50:09 AM (5 years ago)

Author:

alain

Message:

1) Improve the VMM MMAP allocator: implement the "buddy" algorithm
to allocate only aligned blocks.
2) fix a bug in the pthread_join() / pthread_exit() mmechanism.

File:

• trunk/kernel/syscalls/sys_thread_exit.c (modified) (3 diffs)

trunk/kernel/syscalls/sys_thread_exit.c

@@ -33 +33 @@
 #include <syscalls.h>
 
-////////////////////////////////////////
-int sys_thread_exit( void * exit_value )
+/////////////////////////////////////////
+int sys_thread_exit( void * exit_status )
 {
+    error_t     error;
+    vseg_t    * vseg;
+
         thread_t  * this      = CURRENT_THREAD;
     trdid_t     trdid     = this->trdid;
     process_t * process   = this->process;
     pid_t       pid       = process->pid;
+    
+    // check exit_value pointer in user space if required
+    if( exit_status != NULL )
+    {
+        error = vmm_get_vseg( process , (intptr_t)exit_status  , &vseg );
 
-    // check exit_value argument
-    if( exit_value != NULL )
-    {
+        if( error )
+            {
 
 #if DEBUG_SYSCALLS_ERROR
-printk("\n[ERROR] in %s : thread[%x,%x] / exit_value argument %x must be NULL\n",
-__FUNCTION__ , pid, trdid , exit_value );
+printk("\n[ERROR] in %s : exit_status buffer %x unmapped / thread[%x,%x]\n",
+__FUNCTION__, (intptr_t)exit_status, process->pid, this->trdid );
 #endif
-        this->errno = EINVAL;
-        return -1;
+            this->errno = EINVAL;
+                return -1;
+        }
+    }
+
+        // check busylocks
+    uint32_t count = this->busylocks;
+        if( count )
+        {
+
+#if DEBUG_SYSCALLS_ERROR
+printk("\n[ERROR] in %s : busylocks count = %d  / thread[%x,%x]\n",
+__FUNCTION__ , count, process->pid, this->trdid );
+#endif
+            this->errno = EINVAL;
+                return -1;
     }
 
     // If calling thread is the main thread, the process must be deleted. 
-    // => delete all process threads and synchronise with parent process.
-    // If calling thread is not the main thread, it must be deleted.
-    // => block the thread and mark it for delete.
-    if( (CXY_FROM_PID( pid ) == local_cxy) && (LTID_FROM_TRDID(trdid) == 0) )
+    // => delete all process threads and synchronize with parent process.
+    // If calling thread is not the main thread, only this thread must be deleted.
+    // => register exit_status in thread descriptor, block the thread, 
+    //    mark it for delete, and synchronize with joining thread. 
+
+    if( (CXY_FROM_PID( pid ) == local_cxy) && (LTID_FROM_TRDID(trdid) == 0) )  // main
     {
 
@@ -69 +92 @@
         sys_exit( 0 );
     }
-    else
+    else                                                             // not the main
     {
 
@@ -78 +101 @@
 __FUNCTION__ , pid , trdid , (uint32_t)tm_start );
 #endif
+        // register exit_status in thread descriptor
+        this->exit_status = exit_status;
+
         // block calling thread and mark it for delete,
-        thread_delete( XPTR( local_cxy , this ) , pid , false );
+        thread_delete( XPTR( local_cxy , this ) , false );   // not forced
 
         // deschedule