mm,kmemleak-test.c: move kmemleak-test.c to samples dir

kmemleak-test.c is just a kmemleak test module, which also can not be used
as a built-in kernel module.  Thus, i think it may should not be in mm
dir, and move the kmemleak-test.c to samples/kmemleak/kmemleak-test.c.
Fix the spelling of built-in by the way.

Signed-off-by: Hui Su <sh_def@163.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Rob Herring <robh@kernel.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Cc: Divya Indi <divya.indi@oracle.com>
Cc: Tomas Winkler <tomas.winkler@intel.com>
Cc: David Howells <dhowells@redhat.com>
Link: https://lkml.kernel.org/r/20200925183729.GA172837@rlk
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 103 insertions, 0 deletions

diff --git a/samples/Makefile b/samples/Makefile
index 754553597581..c3392a595e4b 100644
--- a/samples/Makefile
+++ b/samples/Makefile
@@ -28,3 +28,4 @@ subdir-$(CONFIG_SAMPLE_VFS)		+= vfs
 obj-$(CONFIG_SAMPLE_INTEL_MEI)		+= mei/
 subdir-$(CONFIG_SAMPLE_WATCHDOG)	+= watchdog
 subdir-$(CONFIG_SAMPLE_WATCH_QUEUE)	+= watch_queue
+obj-$(CONFIG_DEBUG_KMEMLEAK_TEST)	+= kmemleak/
diff --git a/samples/kmemleak/Makefile b/samples/kmemleak/Makefile
new file mode 100644
index 000000000000..16b6132c540c
--- /dev/null
+++ b/samples/kmemleak/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+obj-$(CONFIG_DEBUG_KMEMLEAK_TEST) += kmemleak-test.o
diff --git a/samples/kmemleak/kmemleak-test.c b/samples/kmemleak/kmemleak-test.c
new file mode 100644
index 000000000000..7b476eb8285f
--- /dev/null
+++ b/samples/kmemleak/kmemleak-test.c
@@ -0,0 +1,99 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * samples/kmemleak/kmemleak-test.c
+ *
+ * Copyright (C) 2008 ARM Limited
+ * Written by Catalin Marinas <catalin.marinas@arm.com>
+ */
+
+#define pr_fmt(fmt) "kmemleak: " fmt
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/list.h>
+#include <linux/percpu.h>
+#include <linux/fdtable.h>
+
+#include <linux/kmemleak.h>
+
+struct test_node {
+	long header[25];
+	struct list_head list;
+	long footer[25];
+};
+
+static LIST_HEAD(test_list);
+static DEFINE_PER_CPU(void *, kmemleak_test_pointer);
+
+/*
+ * Some very simple testing. This function needs to be extended for
+ * proper testing.
+ */
+static int __init kmemleak_test_init(void)
+{
+	struct test_node *elem;
+	int i;
+
+	pr_info("Kmemleak testing\n");
+
+	/* make some orphan objects */
+	pr_info("kmalloc(32) = %p\n", kmalloc(32, GFP_KERNEL));
+	pr_info("kmalloc(32) = %p\n", kmalloc(32, GFP_KERNEL));
+	pr_info("kmalloc(1024) = %p\n", kmalloc(1024, GFP_KERNEL));
+	pr_info("kmalloc(1024) = %p\n", kmalloc(1024, GFP_KERNEL));
+	pr_info("kmalloc(2048) = %p\n", kmalloc(2048, GFP_KERNEL));
+	pr_info("kmalloc(2048) = %p\n", kmalloc(2048, GFP_KERNEL));
+	pr_info("kmalloc(4096) = %p\n", kmalloc(4096, GFP_KERNEL));
+	pr_info("kmalloc(4096) = %p\n", kmalloc(4096, GFP_KERNEL));
+#ifndef CONFIG_MODULES
+	pr_info("kmem_cache_alloc(files_cachep) = %p\n",
+		kmem_cache_alloc(files_cachep, GFP_KERNEL));
+	pr_info("kmem_cache_alloc(files_cachep) = %p\n",
+		kmem_cache_alloc(files_cachep, GFP_KERNEL));
+#endif
+	pr_info("vmalloc(64) = %p\n", vmalloc(64));
+	pr_info("vmalloc(64) = %p\n", vmalloc(64));
+	pr_info("vmalloc(64) = %p\n", vmalloc(64));
+	pr_info("vmalloc(64) = %p\n", vmalloc(64));
+	pr_info("vmalloc(64) = %p\n", vmalloc(64));
+
+	/*
+	 * Add elements to a list. They should only appear as orphan
+	 * after the module is removed.
+	 */
+	for (i = 0; i < 10; i++) {
+		elem = kzalloc(sizeof(*elem), GFP_KERNEL);
+		pr_info("kzalloc(sizeof(*elem)) = %p\n", elem);
+		if (!elem)
+			return -ENOMEM;
+		INIT_LIST_HEAD(&elem->list);
+		list_add_tail(&elem->list, &test_list);
+	}
+
+	for_each_possible_cpu(i) {
+		per_cpu(kmemleak_test_pointer, i) = kmalloc(129, GFP_KERNEL);
+		pr_info("kmalloc(129) = %p\n",
+			per_cpu(kmemleak_test_pointer, i));
+	}
+
+	return 0;
+}
+module_init(kmemleak_test_init);
+
+static void __exit kmemleak_test_exit(void)
+{
+	struct test_node *elem, *tmp;
+
+	/*
+	 * Remove the list elements without actually freeing the
+	 * memory.
+	 */
+	list_for_each_entry_safe(elem, tmp, &test_list, list)
+		list_del(&elem->list);
+}
+module_exit(kmemleak_test_exit);
+
+MODULE_LICENSE("GPL");