o Don't add a scope system thread's KSE to the list of available

  KSEs when it's thread exits; allow the GC handler to do that.

o Make spinlock/spinlock critical regions.

The following were submitted by davidxu

  o Alow thr_switch() to take a null mailbox argument.

  o Better protect cancellation checks.

  o Don't set KSE specific data when creating new KSEs; rely on the
    first upcall of the KSE to set it.

  o Add the ability to set the maximum concurrency level and do this
    automatically.  We should have a way to enable/disable this with
    some sort of tunable because some applications may not want this
    to be the default.

  o Hold the scheduling lock across thread switch calls.

  o If scheduling of a thread fails, make sure to remove it from the list
    of active threads.

  o Better protect accesses to a joining threads when the target thread is
    exited and detached.

  o Remove some macro definitions that are now provided by <sys/kse.h>.

  o Don't leave the library in threaded mode if creation of the initial
    KSE fails.

  o Wakeup idle KSEs when there are threads ready to run.

  o Maintain the number of threads active in the priority queue.

1 files changed, 6 insertions, 8 deletions

diff --git a/lib/libpthread/thread/thr_join.c b/lib/libpthread/thread/thr_join.c
index 77e3a8c..7cbc192 100644
--- a/lib/libpthread/thread/thr_join.c
+++ b/lib/libpthread/thread/thr_join.c
@@ -70,16 +70,16 @@ _pthread_join(pthread_t pthread, void **thread_return)
 		return (ESRCH);
 	}
 
+	THR_SCHED_LOCK(curthread, pthread);
 	/* Check if this thread has been detached: */
 	if ((pthread->attr.flags & PTHREAD_DETACHED) != 0) {
+		THR_SCHED_UNLOCK(curthread, pthread);
 		/* Remove the reference and return an error: */
 		_thr_ref_delete(curthread, pthread);
 		ret = ESRCH;
 	} else {
 		/* Lock the target thread while checking its state. */
-		THR_SCHED_LOCK(curthread, pthread);
-		if ((pthread->state == PS_DEAD) ||
-		    ((pthread->flags & THR_FLAGS_EXITING) != 0)) {
+		if (pthread->state == PS_DEAD) {
 			if (thread_return != NULL)
 				/* Return the thread's return value: */
 				*thread_return = pthread->ret;
@@ -123,15 +123,13 @@ _pthread_join(pthread_t pthread, void **thread_return)
 			THR_SCHED_UNLOCK(curthread, pthread);
 			_thr_ref_delete(curthread, pthread);
 
-			THR_SCHED_LOCK(curthread, curthread);
-			if (curthread->join_status.thread == pthread)
-				THR_SET_STATE(curthread, PS_JOIN);
-			THR_SCHED_UNLOCK(curthread, curthread);
-
+			THR_LOCK_SWITCH(curthread);
 			while (curthread->join_status.thread == pthread) {
+				THR_SET_STATE(curthread, PS_JOIN);
 				/* Schedule the next thread: */
 				_thr_sched_switch(curthread);
 			}
+			THR_UNLOCK_SWITCH(curthread);
 
 			/*
 			 * The thread return value and error are set by the