1 files changed, 63 insertions, 7 deletions

diff --git a/src/pkg/runtime/os_netbsd.c b/src/pkg/runtime/os_netbsd.c
index 29ea0cb42..cee96ebed 100644
--- a/src/pkg/runtime/os_netbsd.c
+++ b/src/pkg/runtime/os_netbsd.c
@@ -57,18 +57,23 @@ getncpu(void)
 		return 1;
 }
 
+#pragma textflag NOSPLIT
 uintptr
 runtime·semacreate(void)
 {
 	return 1;
 }
 
-#pragma textflag NOSPLIT
-int32
-runtime·semasleep(int64 ns)
+static void
+semasleep(void)
 {
+	int64 ns;
 	Timespec ts;
 
+	ns = (int64)(uint32)g->m->scalararg[0] | (int64)(uint32)g->m->scalararg[1]<<32;
+	g->m->scalararg[0] = 0;
+	g->m->scalararg[1] = 0;
+
 	// spin-mutex lock
 	while(runtime·xchg(&g->m->waitsemalock, 1))
 		runtime·osyield();
@@ -115,7 +120,8 @@ runtime·semasleep(int64 ns)
 			g->m->waitsemacount--;
 			// spin-mutex unlock
 			runtime·atomicstore(&g->m->waitsemalock, 0);
-			return 0;  // semaphore acquired
+			g->m->scalararg[0] = 0; // semaphore acquired
+			return;
 		}
 
 		// semaphore not available.
@@ -128,13 +134,36 @@ runtime·semasleep(int64 ns)
 	// lock held but giving up
 	// spin-mutex unlock
 	runtime·atomicstore(&g->m->waitsemalock, 0);
-	return -1;
+	g->m->scalararg[0] = -1;
+	return;
+}
+
+#pragma textflag NOSPLIT
+int32
+runtime·semasleep(int64 ns)
+{
+	int32 r;
+	void (*fn)(void);
+
+	g->m->scalararg[0] = (uint32)ns;
+	g->m->scalararg[1] = (uint32)(ns>>32);
+	fn = semasleep;
+	runtime·onM(&fn);
+	r = g->m->scalararg[0];
+	g->m->scalararg[0] = 0;
+	return r;
 }
 
+static void badsemawakeup(void);
+
+#pragma textflag NOSPLIT
 void
 runtime·semawakeup(M *mp)
 {
 	uint32 ret;
+	void (*fn)(void);
+	void *oldptr;
+	uintptr oldscalar;
 
 	// spin-mutex lock
 	while(runtime·xchg(&mp->waitsemalock, 1))
@@ -143,12 +172,39 @@ runtime·semawakeup(M *mp)
 	// TODO(jsing) - potential deadlock, see semasleep() for details.
 	// Confirm that LWP is parked before unparking...
 	ret = runtime·lwp_unpark(mp->procid, &mp->waitsemacount);
-	if(ret != 0 && ret != ESRCH)
-		runtime·printf("thrwakeup addr=%p sem=%d ret=%d\n", &mp->waitsemacount, mp->waitsemacount, ret);
+	if(ret != 0 && ret != ESRCH) {
+		// semawakeup can be called on signal stack.
+		// Save old ptrarg/scalararg so we can restore them.
+		oldptr = g->m->ptrarg[0];
+		oldscalar = g->m->scalararg[0];
+		g->m->ptrarg[0] = mp;
+		g->m->scalararg[0] = ret;
+		fn = badsemawakeup;
+		if(g == g->m->gsignal)
+			fn();
+		else
+			runtime·onM(&fn);
+		g->m->ptrarg[0] = oldptr;
+		g->m->scalararg[0] = oldscalar;
+	}
 	// spin-mutex unlock
 	runtime·atomicstore(&mp->waitsemalock, 0);
 }
 
+static void
+badsemawakeup(void)
+{
+	M *mp;
+	int32 ret;
+
+	mp = g->m->ptrarg[0];
+	g->m->ptrarg[0] = nil;
+	ret = g->m->scalararg[0];
+	g->m->scalararg[0] = 0;
+
+	runtime·printf("thrwakeup addr=%p sem=%d ret=%d\n", &mp->waitsemacount, mp->waitsemacount, ret);
+}
+
 void
 runtime·newosproc(M *mp, void *stk)
 {