1 files changed, 78 insertions, 0 deletions
diff --git a/cmd/dtrace/test/tst/common/buffering/tst.ring3.d b/cmd/dtrace/test/tst/common/buffering/tst.ring3.d
new file mode 100644
index 0000000..68e3588
--- /dev/null
+++ b/cmd/dtrace/test/tst/common/buffering/tst.ring3.d
@@ -0,0 +1,78 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+
+/*
+ * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#pragma ident	"%Z%%M%	%I%	%E% SMI"
+
+/*
+ * ASSERTION:
+ *   Positive test for ring buffer policy.
+ *
+ * SECTION: Buffers and Buffering/ring Policy;
+ *	Buffers and Buffering/Buffer Sizes;
+ *	Options and Tunables/bufsize;
+ *	Options and Tunables/bufpolicy
+ */
+
+/*
+ * We make some regrettable assumptions about the implementation in this test.
+ * First, we assume that each entry for the printf() of an int takes _exactly_
+ * eight bytes (four bytes for the EPID, four bytes for the payload).  Second,
+ * we assume that by allocating storage for n + 1 records, we will get exactly
+ * n.  Here is why:  the final predicate that evaluates to false will reserve
+ * space that it won't use.  This act of reservation will advance the wrapped
+ * offset.  That record won't be subsequently used, but the wrapped offset has
+ * advanced.  (And in this case, that old record is clobbered by the exit()
+ * anyway.)  Thirdly:  we rely on t_cpu/cpu_id.  Finally:  we rely on being
+ * able to run on the CPU that we first ran on.
+ */
+#pragma D option bufpolicy=ring
+#pragma D option bufsize=40
+#pragma D option quiet
+
+int n;
+
+BEGIN
+{
+	cpuid = -1;
+}
+
+tick-10msec
+/cpuid == -1/
+{
+	cpuid = curthread->t_cpu->cpu_id;
+}
+
+tick-10msec
+/curthread->t_cpu->cpu_id == cpuid && n < 100/
+{
+	printf("%d\n", n++);
+}
+
+tick-10msec
+/n == 100/
+{
+	exit(0);
+}