PERFORCE change 56961 for review

[David Xu]

http://perforce.freebsd.org/chv.cgi?CH=56961

Change 56961 by davidxu at davidxu_alona on 2004/07/10 14:18:38

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Affected files ...

.. //depot/projects/davidxu_ksedbg/src/lib/libpthread/thread/thr_priority_queue.c#3 edit

Differences ...

==== //depot/projects/davidxu_ksedbg/src/lib/libpthread/thread/thr_priority_queue.c#3 (text+ko) ====

@@ -271,6 +271,16 @@
 			/* Mark the list as not being in the queue: */
 			pql->pl_queued = 0;
 		} else {
+			/*
+			 * note there may be a suspension event during this
+			 * test, If TMDF_DONOTRUNUSER is set after we tested it,
+			 * we will run the thread, this seems be a problem,
+			 * fortunatly, when we are being debugged, all context
+			 * switch will be done by kse_switchin, that is a syscall,
+			 * kse_switchin will check the flag again, the thread
+			 * will be returned via upcall, so next time, UTS won't
+			 * run the thread.
+			 */ 
 			while (pthread != NULL && !THR_IN_CRITICAL(pthread) &&
 			       (pthread->tcb->tcb_tmbx.tm_dflags &
 			         TMDF_DONOTRUNUSER)) {