kunit, slub: add test_kfree_rcu() and test_leak_destroy()

Add a test that will create cache, allocate one object, kfree_rcu() it
and attempt to destroy it. As long as the usage of kvfree_rcu_barrier()
in kmem_cache_destroy() works correctly, there should be no warnings in
dmesg and the test should pass.

Additionally add a test_leak_destroy() test that leaks an object on
purpose and verifies that kmem_cache_destroy() catches it.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>

diff --git a/lib/slub_kunit.c b/lib/slub_kunit.c
index e6667a28c0149141141c34f7ac4e03c1893727ea..6e3a1e5a7142f797fe20a28967657f50a466d4ee 100644 (file)
--- a/lib/slub_kunit.c
+++ b/lib/slub_kunit.c
@@ -5,6 +5,7 @@
 #include <linux/slab.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
+#include <linux/rcupdate.h>
 #include "../mm/slab.h"
 
 static struct kunit_resource resource;
@@ -157,6 +158,34 @@ static void test_kmalloc_redzone_access(struct kunit *test)
        kmem_cache_destroy(s);
 }
 
+struct test_kfree_rcu_struct {
+       struct rcu_head rcu;
+};
+
+static void test_kfree_rcu(struct kunit *test)
+{
+       struct kmem_cache *s = test_kmem_cache_create("TestSlub_kfree_rcu",
+                               sizeof(struct test_kfree_rcu_struct),
+                               SLAB_NO_MERGE);
+       struct test_kfree_rcu_struct *p = kmem_cache_alloc(s, GFP_KERNEL);
+
+       kfree_rcu(p, rcu);
+       kmem_cache_destroy(s);
+
+       KUNIT_EXPECT_EQ(test, 0, slab_errors);
+}
+
+static void test_leak_destroy(struct kunit *test)
+{
+       struct kmem_cache *s = test_kmem_cache_create("TestSlub_kfree_rcu",
+                                                       64, SLAB_NO_MERGE);
+       kmem_cache_alloc(s, GFP_KERNEL);
+
+       kmem_cache_destroy(s);
+
+       KUNIT_EXPECT_EQ(test, 1, slab_errors);
+}
+
 static int test_init(struct kunit *test)
 {
        slab_errors = 0;
@@ -177,6 +206,8 @@ 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_leak_destroy),
        {}
 };