[PATCH] add test for kmem_cache_destroy in a workqueue

[Vlastimil Babka]

---
 lib/slub_kunit.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)

diff --git a/lib/slub_kunit.c b/lib/slub_kunit.c
index f11691315c2f..5fe9775fba05 100644
--- a/lib/slub_kunit.c
+++ b/lib/slub_kunit.c
@@ -6,6 +6,7 @@
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/rcupdate.h>
+#include <linux/delay.h>
 #include "../mm/slab.h"
 
 static struct kunit_resource resource;
@@ -181,6 +182,52 @@ static void test_kfree_rcu(struct kunit *test)
 	KUNIT_EXPECT_EQ(test, 0, slab_errors);
 }
 
+struct cache_destroy_work {
+        struct work_struct work;
+        struct kmem_cache *s;
+};
+
+static void cache_destroy_workfn(struct work_struct *w)
+{
+	struct cache_destroy_work *cdw;
+
+	cdw = container_of(w, struct cache_destroy_work, work);
+
+	kmem_cache_destroy(cdw->s);
+}
+
+static void test_kfree_rcu_wq_destroy(struct kunit *test)
+{
+	struct test_kfree_rcu_struct *p;
+	struct cache_destroy_work cdw;
+	struct workqueue_struct *wq;
+	struct kmem_cache *s;
+
+	if (IS_BUILTIN(CONFIG_SLUB_KUNIT_TEST))
+		kunit_skip(test, "can't do kfree_rcu() when test is built-in");
+
+	INIT_WORK_ONSTACK(&cdw.work, cache_destroy_workfn);
+	wq = alloc_workqueue("test_kfree_rcu_destroy_wq", WQ_UNBOUND | WQ_MEM_RECLAIM, 0);
+	if (!wq)
+		kunit_skip(test, "failed to alloc wq");
+
+	s = test_kmem_cache_create("TestSlub_kfree_rcu_wq_destroy",
+				   sizeof(struct test_kfree_rcu_struct),
+				   SLAB_NO_MERGE);
+	p = kmem_cache_alloc(s, GFP_KERNEL);
+
+	kfree_rcu(p, rcu);
+
+	cdw.s = s;
+	queue_work(wq, &cdw.work);
+	msleep(1000);
+	flush_work(&cdw.work);
+
+	destroy_workqueue(wq);
+
+	KUNIT_EXPECT_EQ(test, 0, slab_errors);
+}
+
 static void test_leak_destroy(struct kunit *test)
 {
 	struct kmem_cache *s = test_kmem_cache_create("TestSlub_leak_destroy",
@@ -254,6 +301,7 @@ static struct kunit_case test_cases[] = {
 	KUNIT_CASE(test_clobber_redzone_free),
 	KUNIT_CASE(test_kmalloc_redzone_access),
 	KUNIT_CASE(test_kfree_rcu),
+	KUNIT_CASE(test_kfree_rcu_wq_destroy),
 	KUNIT_CASE(test_leak_destroy),
 	KUNIT_CASE(test_krealloc_redzone_zeroing),
 	{}
-- 
2.48.1