PERFORCE change 61663 for review

[Julian Elischer]

http://perforce.freebsd.org/chv.cgi?CH=61663

Change 61663 by julian at julian_ref on 2004/09/17 05:41:18

	 create a separate thread_unthread() that we can call from places
	where we are turning off threading so that we canbe sure we are doing
	it properly.

Affected files ...

.. //depot/projects/nsched/sys/kern/kern_kse.c#28 edit
.. //depot/projects/nsched/sys/kern/kern_thr.c#18 edit
.. //depot/projects/nsched/sys/kern/kern_thread.c#37 edit
.. //depot/projects/nsched/sys/sys/proc.h#33 edit

Differences ...

==== //depot/projects/nsched/sys/kern/kern_kse.c#28 (text+ko) ====

@@ -346,8 +346,7 @@
 	 * One possibility is to return to the user. It may not cope well.
 	 * The other possibility would be to let the process exit.
 	 */
-	p->p_flag &= ~(P_SA|P_HADTHREADS);
-	sched_set_concurrency(td->td_ksegrp, 1);
+	thread_unthread(td);
 	mtx_unlock_spin(&sched_lock);
 	PROC_UNLOCK(p);
 #if 1

==== //depot/projects/nsched/sys/kern/kern_thr.c#18 (text+ko) ====


==== //depot/projects/nsched/sys/kern/kern_thread.c#37 (text+ko) ====

@@ -709,6 +709,31 @@
 }
 
 /*
+ * Convert a process with one thread to an unthreaded process.
+ * Called from:
+ *  thread_single(exit)  (called from execve and exit)
+ *  kse_exit()		XXX may need cleaning up wrt KSE stuff
+ */
+void
+thread_unthread(struct thread *td)
+{
+	struct proc *p = td->td_proc;
+
+	KASSERT((p->p_numthreads == 1), ("Unthreading with >1 threads"));
+	upcall_remove(td);
+	p->p_flag &= ~(P_SA|P_HADTHREADS);
+	td->td_mailbox = NULL;
+	td->td_pflags &= ~(TDP_SA | TDP_CAN_UNBIND);
+	p->p_flag &= ~(P_STOPPED_SINGLE | P_SINGLE_EXIT);  /* maybe not */
+	p->p_singlethread = NULL;
+	if (td->td_standin != NULL) {
+		thread_stash(td->td_standin);
+		td->td_standin = NULL;
+	}
+	sched_set_concurrency(td->td_ksegrp, 1);
+}
+
+/*
  * Called from:
  *  thread_exit()
  */
@@ -835,21 +860,10 @@
 		 * we try our utmost  to revert to being a non-threaded
 		 * process.
 		 */
-		upcall_remove(td);
-		p->p_flag &= ~(P_SA|P_HADTHREADS);
-		td->td_mailbox = NULL;
-		td->td_pflags &= ~(TDP_SA | TDP_CAN_UNBIND);
+		thread_unthread(td);
 		p->p_flag &= ~(P_STOPPED_SINGLE | P_SINGLE_EXIT);
-		p->p_singlethread = NULL;
-		if (td->td_standin != NULL) {
-			thread_stash(td->td_standin);
-			td->td_standin = NULL;
-		}
-		sched_set_concurrency(td->td_ksegrp, 1);
-		mtx_unlock_spin(&sched_lock);
-	} else {
-		mtx_unlock_spin(&sched_lock);
 	}
+	mtx_unlock_spin(&sched_lock);
 	return (0);
 }
 

==== //depot/projects/nsched/sys/sys/proc.h#33 (text+ko) ====

@@ -892,6 +892,7 @@
 void	thread_unlink(struct thread *td);
 void	thread_unsuspend(struct proc *p);
 void	thread_unsuspend_one(struct thread *td);
+void	thread_unthread(struct thread *td);
 int	thread_userret(struct thread *td, struct trapframe *frame);
 int	thread_upcall_check(struct thread *td);
 void	thread_user_enter(struct thread *td);