[PATCH v30 12/13] mm/damon: Add user space selftests

[SeongJae Park <sj38.park@gmail.com>]

From: SeongJae Park <sjpark@amazon.de>

This commit adds a simple user space tests for DAMON.  The tests are
using kselftest framework.

Signed-off-by: SeongJae Park <sjpark@amazon.de>
---
 tools/testing/selftests/damon/Makefile        |  7 ++
 .../selftests/damon/_chk_dependency.sh        | 28 +++++++
 .../testing/selftests/damon/debugfs_attrs.sh  | 75 +++++++++++++++++++
 3 files changed, 110 insertions(+)
 create mode 100644 tools/testing/selftests/damon/Makefile
 create mode 100644 tools/testing/selftests/damon/_chk_dependency.sh
 create mode 100755 tools/testing/selftests/damon/debugfs_attrs.sh

diff --git a/tools/testing/selftests/damon/Makefile b/tools/testing/selftests/damon/Makefile
new file mode 100644
index 000000000000..8a3f2cd9fec0
--- /dev/null
+++ b/tools/testing/selftests/damon/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+# Makefile for damon selftests
+
+TEST_FILES = _chk_dependency.sh
+TEST_PROGS = debugfs_attrs.sh
+
+include ../lib.mk
diff --git a/tools/testing/selftests/damon/_chk_dependency.sh b/tools/testing/selftests/damon/_chk_dependency.sh
new file mode 100644
index 000000000000..0189db81550b
--- /dev/null
+++ b/tools/testing/selftests/damon/_chk_dependency.sh
@@ -0,0 +1,28 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+# Kselftest framework requirement - SKIP code is 4.
+ksft_skip=4
+
+DBGFS=/sys/kernel/debug/damon
+
+if [ $EUID -ne 0 ];
+then
+	echo "Run as root"
+	exit $ksft_skip
+fi
+
+if [ ! -d "$DBGFS" ]
+then
+	echo "$DBGFS not found"
+	exit $ksft_skip
+fi
+
+for f in attrs target_ids monitor_on
+do
+	if [ ! -f "$DBGFS/$f" ]
+	then
+		echo "$f not found"
+		exit 1
+	fi
+done
diff --git a/tools/testing/selftests/damon/debugfs_attrs.sh b/tools/testing/selftests/damon/debugfs_attrs.sh
new file mode 100755
index 000000000000..60342d6c86d8
--- /dev/null
+++ b/tools/testing/selftests/damon/debugfs_attrs.sh
@@ -0,0 +1,75 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+test_write_result() {
+	file=$1
+	content=$2
+	orig_content=$3
+	expect_reason=$4
+	expected=$5
+
+	echo "$content" > "$file"
+	if [ $? -ne "$expected" ]
+	then
+		echo "writing $content to $file doesn't return $expected"
+		echo "expected because: $expect_reason"
+		echo "$orig_content" > "$file"
+		exit 1
+	fi
+}
+
+test_write_succ() {
+	test_write_result "$1" "$2" "$3" "$4" 0
+}
+
+test_write_fail() {
+	test_write_result "$1" "$2" "$3" "$4" 1
+}
+
+test_content() {
+	file=$1
+	orig_content=$2
+	expected=$3
+	expect_reason=$4
+
+	content=$(cat "$file")
+	if [ "$content" != "$content" ]
+	then
+		echo "reading $file expected $expected but $content"
+		echo "expected because: $expect_reason"
+		echo "$orig_content" > "$file"
+		exit 1
+	fi
+}
+
+source ./_chk_dependency.sh
+
+# Test attrs file
+# ===============
+
+file="$DBGFS/attrs"
+orig_content=$(cat "$file")
+
+test_write_succ "$file" "1 2 3 4 5" "$orig_content" "valid input"
+test_write_fail "$file" "1 2 3 4" "$orig_content" "no enough fields"
+test_write_fail "$file" "1 2 3 5 4" "$orig_content" \
+	"min_nr_regions > max_nr_regions"
+test_content "$file" "$orig_content" "1 2 3 4 5" "successfully written"
+echo "$orig_content" > "$file"
+
+# Test target_ids file
+# ====================
+
+file="$DBGFS/target_ids"
+orig_content=$(cat "$file")
+
+test_write_succ "$file" "1 2 3 4" "$orig_content" "valid input"
+test_write_succ "$file" "1 2 abc 4" "$orig_content" "still valid input"
+test_content "$file" "$orig_content" "1 2" "non-integer was there"
+test_write_succ "$file" "abc 2 3" "$orig_content" "the file allows wrong input"
+test_content "$file" "$orig_content" "" "wrong input written"
+test_write_succ "$file" "" "$orig_content" "empty input"
+test_content "$file" "$orig_content" "" "empty input written"
+echo "$orig_content" > "$file"
+
+echo "PASS"
-- 
2.17.1