[PATCH i-g-t v2 3/3] tests/xe_intel_bb: check multithreading rescans won't segfault

["Zbigniew Kempczyński" <zbigniew.kempczynski@intel.com>]

This test is likely only for checking purposes, it doesn't makes
sense to merge it after series review.

Signed-off-by: Zbigniew Kempczyński <zbigniew.kempczynski@intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Cc: Kamil Konieczny <kamil.konieczny@linux.intel.com>
---
 tests/intel-ci/xe-fast-feedback.testlist |  1 +
 tests/intel/xe_intel_bb.c                | 47 ++++++++++++++++++++++++
 2 files changed, 48 insertions(+)

diff --git a/tests/intel-ci/xe-fast-feedback.testlist b/tests/intel-ci/xe-fast-feedback.testlist
index 0234d3e72d..7adb9a3436 100644
--- a/tests/intel-ci/xe-fast-feedback.testlist
+++ b/tests/intel-ci/xe-fast-feedback.testlist
@@ -7,6 +7,7 @@ igt@fbdev@nullptr
 igt@fbdev@read
 igt@fbdev@write
 
+igt@xe_intel_bb@multithread-open
 igt@kms_addfb_basic@addfb25-4-tiled
 igt@kms_addfb_basic@addfb25-bad-modifier
 igt@kms_addfb_basic@addfb25-modifier-no-flag
diff --git a/tests/intel/xe_intel_bb.c b/tests/intel/xe_intel_bb.c
index 845052bf26..5df009f9ed 100644
--- a/tests/intel/xe_intel_bb.c
+++ b/tests/intel/xe_intel_bb.c
@@ -18,6 +18,7 @@
 
 #include "igt.h"
 #include "igt_crc.h"
+#include "igt_device_scan.h"
 #include "intel_blt.h"
 #include "intel_bufops.h"
 #include "intel_mocs.h"
@@ -950,6 +951,49 @@ static int render(struct buf_ops *bops, uint32_t tiling,
 	return fails;
 }
 
+/**
+ * SUBTEST: multithread-open
+ * Description: check device scanning when multiple threads are involved
+ */
+static void *__single_open(void *data)
+{
+	struct igt_device_card card;
+	int fd;
+
+	igt_info("Thread: %d\n", (int)to_user_pointer(data));
+
+	for (int i = 0; i < 5; i++)
+		igt_devices_scan();
+
+	igt_assert_eq(igt_device_card_match("pci:vendor=intel", &card), true);
+	igt_info("Device detail: %s, %s, %s\n", card.subsystem, card.card, card.render);
+
+	fd = igt_open_card(&card);
+	igt_info("Fd: %d\n", fd);
+	igt_assert(fd >= 0);
+	close(fd);
+
+	return NULL;
+}
+
+#define NUM_THREADS 100
+static void multithread_open(void)
+{
+	pthread_t pth[NUM_THREADS];
+	int i, ret;
+
+	for (i = 0; i < NUM_THREADS; i++) {
+		ret = pthread_create(&pth[i], NULL, __single_open,
+				     from_user_pointer(i));
+		igt_assert_eq(ret, 0);
+	}
+
+	for (i = 0; i < NUM_THREADS; i++) {
+		ret = pthread_join(pth[i], NULL);
+		igt_assert_eq(ret, 0);
+	}
+}
+
 static int opt_handler(int opt, int opt_index, void *data)
 {
 	switch (opt) {
@@ -1063,6 +1107,9 @@ igt_main_args("dpib", NULL, help_str, opt_handler, NULL)
 		}
 	}
 
+	igt_subtest("multithread-open")
+		multithread_open();
+
 	igt_fixture {
 		buf_ops_destroy(bops);
 		drm_close_driver(xe);
-- 
2.34.1