- * Place the specified thread in the list of threads to swapin. It
- * is assumed that the thread is locked, therefore we are at splsched.
- *
- * We don't bother with stack_alloc_try to optimize swapin;
- * our callers have already tried that route.
+ * Place the specified thread in the list of threads to swapin.
+ * Called with thread locked, returned unlocked.