PERFORCE change 52492 for review

[Marcel Moolenaar]

http://perforce.freebsd.org/chv.cgi?CH=52492

Change 52492 by marcel at marcel_nfs on 2004/05/07 22:16:29

	Add thread support functions:
	o  kdb_thr_first() and kdb_thr_next() are to be used when
	   iterating over the threads. Typically one calls these
	   to list threads.
	o  kdb_thr_lookup() maps a TID onto a struct thread. This
	   allows thread selection based on TIDs.
	o  kdb_thr_select() is used to switch the current thread.
	
	Currently threads that haven't run yet are considered
	non-existent. This is mostly done to avoid complexities
	caused by not having a valid or complete trapframe.
	
	Remove kdb_set_thread().

Affected files ...

.. //depot/projects/gdb/sys/kern/subr_kdb.c#12 edit
.. //depot/projects/gdb/sys/sys/kdb.h#9 edit

Differences ...

==== //depot/projects/gdb/sys/kern/subr_kdb.c#12 (text+ko) ====

@@ -193,20 +193,6 @@
 }
 
 /*
- * Handle contexts.
- */
-
-void *
-kdb_jmpbuf(jmp_buf new)
-{
-	void *old;
-
-	old = kdb_jmpbufp;
-	kdb_jmpbufp = new;
-	return (old);
-}
-
-/*
  * Enter the currently selected debugger. If a message has been provided,
  * it is printed first. If the debugger does not support the enter method,
  * it is entered by using breakpoint(), which enters the debugger through
@@ -260,24 +246,79 @@
 }
 
 /*
- * Switch the current thread.
+ * Handle contexts.
+ */
+
+void *
+kdb_jmpbuf(jmp_buf new)
+{
+	void *old;
+
+	old = kdb_jmpbufp;
+	kdb_jmpbufp = new;
+	return (old);
+}
+
+/*
+ * Thread related support functions.
  */
 
-int
-kdb_set_thread(pid_t tid)
+struct thread *
+kdb_thr_first(void)
 {
 	struct proc *p;
+	struct thread *thr;
 
 	p = LIST_FIRST(&allproc);
-	while (p != NULL && p->p_pid != tid)
+	while (p != NULL) {
+		thr = FIRST_THREAD_IN_PROC(p);
+		while (thr != NULL && thr->td_last_frame == NULL)
+			thr = TAILQ_NEXT(thr, td_plist);
+		if (thr != NULL)
+			return (thr);
 		p = LIST_NEXT(p, p_list);
-	if (p != NULL) {
-		kdb_thread = FIRST_THREAD_IN_PROC(p);
-		kdb_frame = kdb_thread->td_last_frame;
-		if (kdb_frame == NULL)
-			kdb_frame = kdb_thread->td_frame;
 	}
-	return ((p != NULL) ? 1 : 0);
+	return (NULL);
+}
+
+struct thread *
+kdb_thr_lookup(pid_t tid)
+{
+	struct thread *thr;
+
+	thr = kdb_thr_first();
+	while (thr != NULL && thr->td_tid != tid)
+		thr = kdb_thr_next(thr);
+	return (thr);
+}
+
+struct thread *
+kdb_thr_next(struct thread *thr)
+{
+	struct proc *p;
+
+	p = thr->td_proc;
+	thr = TAILQ_NEXT(thr, td_plist);
+	do {
+		while (thr != NULL && thr->td_last_frame == NULL)
+			thr = TAILQ_NEXT(thr, td_plist);
+		if (thr != NULL)
+			return (thr);
+		p = LIST_NEXT(p, p_list);
+		if (p != NULL)
+			thr = FIRST_THREAD_IN_PROC(p);
+	} while (p != NULL);
+	return (NULL);
+}
+
+int
+kdb_thr_select(struct thread *thr)
+{
+	if (thr == NULL || thr->td_last_frame == NULL)
+		return (EINVAL);
+	kdb_thread = thr;
+	kdb_frame = kdb_thread->td_last_frame;
+	return (0);
 }
 
 /*

==== //depot/projects/gdb/sys/sys/kdb.h#9 (text+ko) ====

@@ -65,7 +65,10 @@
 void	kdb_enter(const char *);
 void	kdb_init(void);
 void *	kdb_jmpbuf(jmp_buf);
-int	kdb_set_thread(pid_t);
+struct thread *kdb_thr_first(void);
+struct thread *kdb_thr_lookup(pid_t);
+struct thread *kdb_thr_next(struct thread *);
+int	kdb_thr_select(struct thread *);
 int	kdb_trap(int, int, struct trapframe *);
 
 #endif /* !_SYS_KDB_H_ */