[PATCH i-g-t 1/1] tests/intel/xe_debugfs: Add tests to read all debugfs and sysfs files

[Peter Senna Tschudin <peter.senna@linux.intel.com>]

The existing tests/intel/debugfs_test.c scans and reads all relevant
files from sysfs and debugfs, but it is specific to i915, leaving a gap
for Xe.

A similar test exists for Xe in tests/intel/xe_debugfs.c, but it has two
gaps compared to the i915 counterpart:
 - It lacks sysfs file testing.
 - It does not attempt to read all debugfs files.

This commit addresses these gaps by adding two new tests to
tests/intel/xe_debugfs.c:
 - sysfs_read_all_entries
 - debugfs_read_all_entries

Both tests use the function read_and_discard_sysfs_entries(), which was
copied from tests/intel/debugfs_test.c.

Cc: rodrigo.vivi@intel.com
Cc: katarzyna.piecielska@intel.com
Signed-off-by: Peter Senna Tschudin <peter.senna@linux.intel.com>
---
 tests/intel/xe_debugfs.c | 88 +++++++++++++++++++++++++++++++++++++++-
 1 file changed, 87 insertions(+), 1 deletion(-)

diff --git a/tests/intel/xe_debugfs.c b/tests/intel/xe_debugfs.c
index ec8b0d0b5..0b468c4d4 100644
--- a/tests/intel/xe_debugfs.c
+++ b/tests/intel/xe_debugfs.c
@@ -235,15 +235,90 @@ static int opt_handler(int option, int option_index, void *input)
 	return IGT_OPT_HANDLER_SUCCESS;
 }
 
+/**
+ * SUBTEST: sysfs_read_all_entries
+ * Description: Read all entries from sysfs path.
+ *
+ * SUBTEST: debugfs_read_all_entries
+ * Description: Read all entries from debugfs path.
+ */
+static void read_and_discard_sysfs_entries(int path_fd, int indent)
+{
+	struct dirent *dirent;
+	DIR *dir;
+	char tabs[8];
+	int i;
+
+	igt_assert(indent < sizeof(tabs) - 1);
+
+	for (i = 0; i < indent; i++)
+		tabs[i] = '\t';
+	tabs[i] = '\0';
+
+	dir = fdopendir(path_fd);
+	if (!dir)
+		return;
+
+	while ((dirent = readdir(dir))) {
+		if (!strcmp(dirent->d_name, ".") ||
+		    !strcmp(dirent->d_name, ".."))
+			continue;
+
+		if (dirent->d_type == DT_DIR) {
+			int sub_fd;
+
+			sub_fd = openat(path_fd, dirent->d_name,
+					O_RDONLY | O_DIRECTORY);
+			if (sub_fd < 0)
+				continue;
+
+			igt_debug("%sEntering subdir %s\n", tabs, dirent->d_name);
+			read_and_discard_sysfs_entries(sub_fd, indent + 1);
+			close(sub_fd);
+		} else if (dirent->d_type == DT_REG) {
+			char buf[512];
+			int sub_fd;
+			ssize_t ret;
+
+			igt_kmsg(KMSG_DEBUG "Reading file \"%s\"\n", dirent->d_name);
+			igt_debug("%sReading file \"%s\"\n", tabs, dirent->d_name);
+			igt_set_timeout(5, "reading sysfs entry");
+
+			sub_fd = openat(path_fd, dirent->d_name, O_RDONLY | O_NONBLOCK);
+			if (sub_fd == -1) {
+				igt_debug("%sCould not open file \"%s\" with error: %m\n",
+					  tabs, dirent->d_name);
+				continue;
+			}
+
+			do {
+				ret = read(sub_fd, buf, sizeof(buf));
+			} while (ret == sizeof(buf));
+
+			if (ret == -1)
+				igt_debug("%sCould not read file \"%s\" with error: %m\n",
+					  tabs, dirent->d_name);
+
+			igt_reset_timeout();
+			close(sub_fd);
+		}
+	}
+	closedir(dir);
+}
+
 igt_main_args("", long_options, help_str, opt_handler, NULL)
 {
 	char devnode[PATH_MAX];
 	int fd;
 	int gt;
+	int debugfs;
+	int sysfs;
 
 	igt_fixture {
 		fd = drm_open_driver(DRIVER_XE);
 		__igt_debugfs_dump(fd, "info", IGT_LOG_INFO);
+		debugfs = igt_debugfs_dir(fd);
+		sysfs = igt_sysfs_open(fd);
 	}
 
 	igt_subtest("base") {
@@ -263,6 +338,17 @@ igt_main_args("", long_options, help_str, opt_handler, NULL)
 		test_forcewake(fd);
 	}
 
-	igt_fixture
+	igt_describe("Read all entries from sysfs path.");
+	igt_subtest("sysfs_read_all_entries")
+		read_and_discard_sysfs_entries(sysfs, 0);
+
+	igt_describe("Read all entries from debugfs path.");
+	igt_subtest("debugfs_read_all_entries")
+		read_and_discard_sysfs_entries(debugfs, 0);
+
+	igt_fixture {
+		close(sysfs);
+		close(debugfs);
 		drm_close_driver(fd);
+	}
 }
-- 
2.34.1