[PATCH v19 06/11] selftests: tracing: Add a basic testcase for wprobe

["Masami Hiramatsu (Google)" <mhiramat@kernel.org>]

From: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Add 'add_remove_wprobe.tc' testcase for testing wprobe event that
tests adding and removing operations of the wprobe event.

Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
 Changes in v17:
  - Catch failures when enabling wprobe and call exit_unresolved
    in case hardware watchpoints are exhausted.
 Changes in v9:
  - Fix command check logic to prevent early exit under 'set -e'
    (errexit) when grep or test fails.
  - Simplify enable/disable status checks by removing cat pipes.
 Changes in v8:
  - Fixed silently test failure path.
---
 tools/testing/selftests/ftrace/config              |    1 
 .../ftrace/test.d/dynevent/add_remove_wprobe.tc    |   66 ++++++++++++++++++++
 2 files changed, 67 insertions(+)
 create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/add_remove_wprobe.tc

diff --git a/tools/testing/selftests/ftrace/config b/tools/testing/selftests/ftrace/config
index 29f05f7c6e2c..c2caea1ba1f5 100644
--- a/tools/testing/selftests/ftrace/config
+++ b/tools/testing/selftests/ftrace/config
@@ -33,3 +33,4 @@ CONFIG_SYNTH_EVENTS=y
 CONFIG_TRACER_SNAPSHOT=y
 CONFIG_UPROBES=y
 CONFIG_UPROBE_EVENTS=y
+CONFIG_WPROBE_EVENTS=y
diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_wprobe.tc b/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_wprobe.tc
new file mode 100644
index 000000000000..3c622fb07e7f
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_wprobe.tc
@@ -0,0 +1,66 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Generic dynamic event - add/remove wprobe events
+# requires: dynamic_events "w[:[<group>/][<event>]] [r|w|rw]@<addr>[:<len>]":README
+
+echo 0 > events/enable
+echo > dynamic_events
+
+# Use jiffies as a variable that is frequently written to.
+TARGET=jiffies
+
+echo "w:my_wprobe w@$TARGET" >> dynamic_events
+
+if ! grep -q my_wprobe dynamic_events; then
+    echo "Failed to create wprobe event"
+    exit_fail
+fi
+
+if [ ! -d events/wprobes/my_wprobe ]; then
+    echo "Failed to create wprobe event directory"
+    exit_fail
+fi
+
+if ! echo 1 > events/wprobes/my_wprobe/enable; then
+    echo "Failed to enable wprobe (hardware watchpoints may be exhausted)"
+    exit_unresolved
+fi
+
+# Check if the event is enabled
+if ! grep -q 1 events/wprobes/my_wprobe/enable; then
+    echo "Failed to enable wprobe event"
+    exit_fail
+fi
+
+# Let some time pass to trigger the breakpoint
+sleep 1
+
+# Check if we got any trace output
+if ! grep -q my_wprobe trace; then
+    echo "wprobe event was not triggered"
+    exit_fail
+fi
+
+echo 0 > events/wprobes/my_wprobe/enable
+
+# Check if the event is disabled
+if ! grep -q 0 events/wprobes/my_wprobe/enable; then
+    echo "Failed to disable wprobe event"
+    exit_fail
+fi
+
+echo "-:my_wprobe" >> dynamic_events
+
+if grep -q my_wprobe dynamic_events; then
+    echo "Failed to remove wprobe event"
+    exit_fail
+fi
+
+if [ -d events/wprobes/my_wprobe ]; then
+    echo "Failed to remove wprobe event directory"
+    exit_fail
+fi
+
+clear_trace
+
+exit 0