[PATCH 05/22] Set the ERROR PRID in BPF code

eugene.loh
2024-08-29T05:22:30Z

From: Eugene Loh <eugene.loh@oracle.com>

We use the fact that the ERROR PRID is always 3.

Signed-off-by: Eugene Loh <eugene.loh@oracle.com>
---
bpf/probe_error.c | 3 +++
test/unittest/builtinvar/tst.id_ERROR.d | 32 +++++++++++++++++++++++
test/unittest/builtinvar/tst.id_ERROR.r | 3 +++
test/unittest/builtinvar/tst.id_ERROR.r.p | 4 +++
4 files changed, 42 insertions(+)
create mode 100644 test/unittest/builtinvar/tst.id_ERROR.d
create mode 100644 test/unittest/builtinvar/tst.id_ERROR.r
create mode 100755 test/unittest/builtinvar/tst.id_ERROR.r.p

diff --git a/bpf/probe_error.c b/bpf/probe_error.c
index c8ddcdfa..ee1a1793 100644
--- a/bpf/probe_error.c
+++ b/bpf/probe_error.c
@@ -26,6 +26,7 @@ noinline void dt_probe_error(const dt_dctx_t *dctx, uint64_t pc, uint64_t fault,
uint64_t illval)
{
dt_mstate_t *mst = dctx->mst;
+ int oldprid = mst->prid;

mst->argv[0] = 0;
mst->argv[1] = mst->epid;
@@ -34,7 +35,9 @@ noinline void dt_probe_error(const dt_dctx_t *dctx, uint64_t pc, uint64_t fault,
mst->argv[4] = fault;
mst->argv[5] = illval;

+ mst->prid = 3;
dt_error(dctx);
+ mst->prid = oldprid;

mst->fault = fault;
}
diff --git a/test/unittest/builtinvar/tst.id_ERROR.d b/test/unittest/builtinvar/tst.id_ERROR.d
new file mode 100644
index 00000000..59021c60
--- /dev/null
+++ b/test/unittest/builtinvar/tst.id_ERROR.d
@@ -0,0 +1,32 @@
+/*
+ * Oracle Linux DTrace.
+ * Copyright (c) 2024, Oracle and/or its affiliates. All rights reserved.
+ * Licensed under the Universal Permissive License v 1.0 as shown at
+ * http://oss.oracle.com/licenses/upl.
+ */
+
+/*
+ * ASSERTION:
+ * The id in the ERROR probe is 3.
+ *
+ * SECTION: Variables/Built-in Variables
+ */
+
+#pragma D option quiet
+
+tick-1s
+{
+ /* trigger the ERROR probe */
+ trace(*((int*)0));
+}
+
+tick-2s
+{
+ exit(1);
+}
+
+ERROR
+{
+ printf("id of the ERROR probe = %d\n", id);
+ exit(0);
+}
diff --git a/test/unittest/builtinvar/tst.id_ERROR.r b/test/unittest/builtinvar/tst.id_ERROR.r
new file mode 100644
index 00000000..95974abe
--- /dev/null
+++ b/test/unittest/builtinvar/tst.id_ERROR.r
@@ -0,0 +1,3 @@
+id of the ERROR probe = 3
+
+-- @@stderr --
diff --git a/test/unittest/builtinvar/tst.id_ERROR.r.p b/test/unittest/builtinvar/tst.id_ERROR.r.p
new file mode 100755
index 00000000..884b43f4
--- /dev/null
+++ b/test/unittest/builtinvar/tst.id_ERROR.r.p
@@ -0,0 +1,4 @@
+#!/usr/bin/gawk -f
+
+# Drop the line with run-dependent PRID for profile probe.
+!/error on enabled probe ID/ { print }
--
2.43.5