The libthr code makes use of higher-level primitives (pthread_mutex_t and

pthread_cond_t) internaly in addition to the low-level spinlock_t. The
garbage collector mutex and condition variable are two such examples. This
might lead to critical sections nested within critical sections. Implement
a reference counting mechanism so that signals are masked only on the first
entry and unmasked on the last exit.

I'm not sure I like the idea of nested critical sections, but if
the library is going to use the pthread primitives it might be necessary.

Approved by:	re/blanket libthr

1 files changed, 1 insertions, 0 deletions

diff --git a/lib/libthr/thread/thr_private.h b/lib/libthr/thread/thr_private.h
index b02df32..6048bd0 100644
--- a/lib/libthr/thread/thr_private.h
+++ b/lib/libthr/thread/thr_private.h
@@ -426,6 +426,7 @@ struct pthread {
 	u_int64_t		uniqueid; /* for gdb */
 	thr_id_t		thr_id;
 	sigset_t		savedsig;
+	int			crit_ref; /* crit. section netsting level */
 
 	/*
 	 * Lock for accesses to this thread structure.