Support task_wait / task_wait_tid syscalls:

    - Add task_end2 syscall to allow pthread_exit-like retval.
    - Add/maintain task states.
    - Create task parent/child tracking tree.
    - Add task_detach function.
    - Implement wait syscalls.

Make task_exec caller the parent of spawned task:

    Previously the task_exec call caused a message to the
    VFS task, which called task_create and returned the tid
    in response to the message.  This causes the parent of
    the spawned task to appear to be the VFS task.

    Modify task_exec / VFS handling to instead return the
    entry point address on the message and have task_exec call
    task_create directly itself.

Change-Id: I6b6796f45875de37b1ab01e7596639b073820b95
Reviewed-on: http://gfw160.austin.ibm.com:8080/gerrit/443
Tested-by: Jenkins Server
Reviewed-by: Daniel M. Crowell <dcrowell@us.ibm.com>
Reviewed-by: Andrew J. Geissler <andrewg@us.ibm.com>

1 files changed, 11 insertions, 19 deletions

diff --git a/src/sys/vfs/vfs_main.C b/src/sys/vfs/vfs_main.C
index 06a7f9d07..17de12295 100644
--- a/src/sys/vfs/vfs_main.C
+++ b/src/sys/vfs/vfs_main.C
@@ -39,16 +39,6 @@ const char* VFS_ROOT_MSG_VFS = "/msg/vfs";
 
 void vfs_module_init();
 
-/**
- * Call the module start routine
- * @param[in] i_module VfsSystemModule data for the module
- * @param[in] i_param parameter to pass to task_create() for this module
- * @return tid_t of started task or negative value on error.
- * @retval -ENOENT if i_module is NULL
- * @retval -ENOEXEC if there is no start()
- */
-tid_t vfs_exec(VfsSystemModule * i_module, void* i_param);
-
 struct VfsPath
 {
     char key[64];
@@ -123,13 +113,14 @@ void vfs_main(void* i_barrier)
                         vfs_find_module(VFS_MODULES,
                                         (const char *) msg->data[0]);
 
-		    tid_t child = vfs_exec(module,(void*) msg->data[1]);
+		    void* fnptr = vfs_start_entrypoint(module);
 
                     // child == -ENOENT means module not found in base image
                     // so send a message to VFS_MSG queue to look in the
                     // extended image VFS_MSG queue will handle the
                     // msg_respond()
-                    if( child == (tid_t)-ENOENT ) // forward msg to usr vfs
+                    if( fnptr == reinterpret_cast<void*>(-ENOENT) )
+                        // forward msg to usr vfs
                     {
                         VfsEntry::key_type k;
                         strcpy(k.key, VFS_ROOT_MSG_VFS);
@@ -144,13 +135,13 @@ void vfs_main(void* i_barrier)
                         }
                         else  // Cant find VFS_MSG queue - not started yet
                         {
-                            msg->data[0] =  child;
+                            msg->data[0] = (uint64_t) fnptr;
                             msg_respond(vfsMsgQ, msg);
                         }
                     }
                     else // send back child (or errno)
                     {
-                        msg->data[0] = child;
+                        msg->data[0] = (uint64_t) fnptr;
                         msg_respond(vfsMsgQ, msg);
                     }
 		}
@@ -165,21 +156,22 @@ void vfs_main(void* i_barrier)
 
 // ----------------------------------------------------------------------------
 
-tid_t vfs_exec(VfsSystemModule * i_module, void* i_param)
+void* vfs_start_entrypoint(VfsSystemModule * i_module)
 {
-    tid_t child = -ENOENT;
+    void* ptr = reinterpret_cast<void*>(-ENOENT);
     if(i_module != NULL)
     {
         if (i_module->start == NULL)
         {
-            child = -ENOEXEC;  // module has no start() routine
+            // module has no start() routine
+            ptr = reinterpret_cast<void*>(-ENOEXEC);
         }
         else
         {
-            child = task_create(i_module->start, i_param);
+            ptr = reinterpret_cast<void*>(i_module->start);
         }
     }
-    return child;
+    return ptr;
 }