locking/static_keys: Provide a selftest

The 'jump label' self-test is in reality testing static keys - rename things
accordingly.

Also prettify the code in various places while at it.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: benh@kernel.crashing.org
Cc: bp@alien8.de
Cc: davem@davemloft.net
Cc: ddaney@caviumnetworks.com
Cc: heiko.carstens@de.ibm.com
Cc: linux-kernel@vger.kernel.org
Cc: liuj97@gmail.com
Cc: luto@amacapital.net
Cc: michael@ellerman.id.au
Cc: rabin@rab.in
Cc: ralf@linux-mips.org
Cc: rostedt@goodmis.org
Cc: vbabka@suse.cz
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/0c091ecebd78a879ed8a71835d205a691a75ab4e.1438227999.git.jbaron@akamai.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

lib/Kconfig.debug

@@ -1841,12 +1841,12 @@ config MEMTEST
 	        memtest=17, mean do 17 test patterns.
 	  If you are unsure how to answer this question, answer N.
 
-config TEST_JUMP_LABEL
+config TEST_STATIC_KEYS
-	tristate "Test jump label"
+	tristate "Test static keys"
 	default n
 	depends on m
 	help
-	  Test jump labels.
+	  Test the static key interfaces.
 
 	  If unsure, say N.
 

lib/Makefile

@@ -39,8 +39,8 @@ obj-$(CONFIG_TEST_KSTRTOX) += test-kstrtox.o
 obj-$(CONFIG_TEST_LKM) += test_module.o
 obj-$(CONFIG_TEST_RHASHTABLE) += test_rhashtable.o
 obj-$(CONFIG_TEST_USER_COPY) += test_user_copy.o
-obj-$(CONFIG_TEST_JUMP_LABEL) += test_jump_label.o
+obj-$(CONFIG_TEST_STATIC_KEYS) += test_static_keys.o
-obj-$(CONFIG_TEST_JUMP_LABEL) += test_jump_label_base.o
+obj-$(CONFIG_TEST_STATIC_KEYS) += test_static_key_base.o
 
 ifeq ($(CONFIG_DEBUG_KOBJECT),y)
 CFLAGS_kobject.o += -DDEBUG

lib/test_jump_label.c

@@ -1,225 +0,0 @@
-/*
- * Kernel module for testing jump labels.
- *
- * Copyright 2015 Akamai Technologies Inc. All Rights Reserved
- *
- * Authors:
- *      Jason Baron       <jbaron@akamai.com>
- *
- * This software is licensed under the terms of the GNU General Public
- * License version 2, as published by the Free Software Foundation, and
- * may be copied, distributed, and modified under those terms.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- */
-
-#include <linux/module.h>
-#include <linux/jump_label.h>
-
-/* old keys */
-struct static_key old_true_key = STATIC_KEY_INIT_TRUE;
-struct static_key old_false_key = STATIC_KEY_INIT_FALSE;
-
-/* new api */
-DEFINE_STATIC_KEY_TRUE(true_key);
-DEFINE_STATIC_KEY_FALSE(false_key);
-
-/* external */
-extern struct static_key base_old_true_key;
-extern struct static_key base_inv_old_true_key;
-extern struct static_key base_old_false_key;
-extern struct static_key base_inv_old_false_key;
-
-/* new api */
-extern struct static_key_true base_true_key;
-extern struct static_key_true base_inv_true_key;
-extern struct static_key_false base_false_key;
-extern struct static_key_false base_inv_false_key;
-
-
-struct test_branch {
-	bool init_state;
-	struct static_key *key;
-	bool (*test_key)(void);
-};
-
-#define test_key_func(key, branch)	\
-({bool func(void) { return branch(key); } func;	})
-
-static void invert_key(struct static_key *key)
-{
-	if (static_key_enabled(key))
-		static_key_disable(key);
-	else
-		static_key_enable(key);
-}
-
-static void invert_keys(struct test_branch *branches, int size)
-{
-	struct static_key *previous = NULL;
-	int i;
-
-	for (i = 0; i < size; i++) {
-		if (previous != branches[i].key) {
-			invert_key(branches[i].key);
-			previous = branches[i].key;
-		}
-	}
-}
-
-int verify_branches(struct test_branch *branches, int size, bool invert)
-{
-	int i;
-	bool ret, init;
-
-	for (i = 0; i < size; i++) {
-		ret = static_key_enabled(branches[i].key);
-		init = branches[i].init_state;
-		if (ret != (invert ? !init : init))
-			return -EINVAL;
-		ret = branches[i].test_key();
-		if (static_key_enabled(branches[i].key)) {
-			if (!ret)
-				return -EINVAL;
-		} else {
-			if (ret)
-				return -EINVAL;
-		}
-	}
-	return 0;
-}
-
-static int __init test_jump_label_init(void)
-{
-	int ret;
-	int size;
-
-	struct test_branch jump_label_tests[] = {
-		/* internal keys - old keys */
-		{
-			.init_state = true,
-			.key = &old_true_key,
-			.test_key = test_key_func(&old_true_key, static_key_true),
-		},
-		{
-			.init_state = false,
-			.key = &old_false_key,
-			.test_key = test_key_func(&old_false_key, static_key_false),
-		},
-		/* internal keys - new keys */
-		{
-			.init_state = true,
-			.key = &true_key.key,
-			.test_key = test_key_func(&true_key, static_branch_likely),
-		},
-		{
-			.init_state = true,
-			.key = &true_key.key,
-			.test_key = test_key_func(&true_key, static_branch_unlikely),
-		},
-		{
-			.init_state = false,
-			.key = &false_key.key,
-			.test_key = test_key_func(&false_key, static_branch_likely),
-		},
-		{
-			.init_state = false,
-			.key = &false_key.key,
-			.test_key = test_key_func(&false_key, static_branch_unlikely),
-		},
-		/* external keys - old keys */
-		{
-			.init_state = true,
-			.key = &base_old_true_key,
-			.test_key = test_key_func(&base_old_true_key, static_key_true),
-		},
-		{
-			.init_state = false,
-			.key = &base_inv_old_true_key,
-			.test_key = test_key_func(&base_inv_old_true_key, static_key_true),
-		},
-		{
-			.init_state = false,
-			.key = &base_old_false_key,
-			.test_key = test_key_func(&base_old_false_key, static_key_false),
-		},
-		{
-			.init_state = true,
-			.key = &base_inv_old_false_key,
-			.test_key = test_key_func(&base_inv_old_false_key, static_key_false),
-		},
-		/* external keys - new keys */
-		{
-			.init_state = true,
-			.key = &base_true_key.key,
-			.test_key = test_key_func(&base_true_key, static_branch_likely),
-		},
-		{
-			.init_state = true,
-			.key = &base_true_key.key,
-			.test_key = test_key_func(&base_true_key, static_branch_unlikely),
-		},
-		{
-			.init_state = false,
-			.key = &base_inv_true_key.key,
-			.test_key = test_key_func(&base_inv_true_key, static_branch_likely),
-		},
-		{
-			.init_state = false,
-			.key = &base_inv_true_key.key,
-			.test_key = test_key_func(&base_inv_true_key, static_branch_unlikely),
-		},
-		{
-			.init_state = false,
-			.key = &base_false_key.key,
-			.test_key = test_key_func(&base_false_key, static_branch_likely),
-		},
-		{
-			.init_state = false,
-			.key = &base_false_key.key,
-			.test_key = test_key_func(&base_false_key, static_branch_unlikely),
-		},
-		{
-			.init_state = true,
-			.key = &base_inv_false_key.key,
-			.test_key = test_key_func(&base_inv_false_key, static_branch_likely),
-		},
-		{
-			.init_state = true,
-			.key = &base_inv_false_key.key,
-			.test_key = test_key_func(&base_inv_false_key, static_branch_unlikely),
-		},
-	};
-
-	size = ARRAY_SIZE(jump_label_tests);
-
-	ret = verify_branches(jump_label_tests, size, false);
-	if (ret)
-		goto out;
-
-	invert_keys(jump_label_tests, size);
-	ret = verify_branches(jump_label_tests, size, true);
-	if (ret)
-		goto out;
-
-	invert_keys(jump_label_tests, size);
-	ret = verify_branches(jump_label_tests, size, false);
-	if (ret)
-		goto out;
-	return 0;
-out:
-	return ret;
-}
-
-static void __exit test_jump_label_exit(void)
-{
-}
-
-module_init(test_jump_label_init);
-module_exit(test_jump_label_exit);
-
-MODULE_AUTHOR("Jason Baron <jbaron@akamai.com>");
-MODULE_LICENSE("GPL");

lib/test_static_key_base.c

@@ -1,5 +1,5 @@
 /*
- * Kernel module for testing jump labels.
+ * Kernel module for testing static keys.
  *
  * Copyright 2015 Akamai Technologies Inc. All Rights Reserved
  *
@@ -47,7 +47,7 @@ static void invert_key(struct static_key *key)
 		static_key_enable(key);
 }
 
-static int __init test_jump_label_base_init(void)
+static int __init test_static_key_base_init(void)
 {
 	invert_key(&base_inv_old_true_key);
 	invert_key(&base_inv_old_false_key);
@@ -57,12 +57,12 @@ static int __init test_jump_label_base_init(void)
 	return 0;
 }
 
-static void __exit test_jump_label_base_exit(void)
+static void __exit test_static_key_base_exit(void)
 {
 }
 
-module_init(test_jump_label_base_init);
+module_init(test_static_key_base_init);
-module_exit(test_jump_label_base_exit);
+module_exit(test_static_key_base_exit);
 
 MODULE_AUTHOR("Jason Baron <jbaron@akamai.com>");
 MODULE_LICENSE("GPL");

lib/test_static_keys.c

@@ -0,0 +1,225 @@
+/*
+ * Kernel module for testing static keys.
+ *
+ * Copyright 2015 Akamai Technologies Inc. All Rights Reserved
+ *
+ * Authors:
+ *      Jason Baron       <jbaron@akamai.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/jump_label.h>
+
+/* old keys */
+struct static_key old_true_key	= STATIC_KEY_INIT_TRUE;
+struct static_key old_false_key	= STATIC_KEY_INIT_FALSE;
+
+/* new api */
+DEFINE_STATIC_KEY_TRUE(true_key);
+DEFINE_STATIC_KEY_FALSE(false_key);
+
+/* external */
+extern struct static_key base_old_true_key;
+extern struct static_key base_inv_old_true_key;
+extern struct static_key base_old_false_key;
+extern struct static_key base_inv_old_false_key;
+
+/* new api */
+extern struct static_key_true base_true_key;
+extern struct static_key_true base_inv_true_key;
+extern struct static_key_false base_false_key;
+extern struct static_key_false base_inv_false_key;
+
+
+struct test_key {
+	bool			init_state;
+	struct static_key	*key;
+	bool			(*test_key)(void);
+};
+
+#define test_key_func(key, branch) \
+	({bool func(void) { return branch(key); } func;	})
+
+static void invert_key(struct static_key *key)
+{
+	if (static_key_enabled(key))
+		static_key_disable(key);
+	else
+		static_key_enable(key);
+}
+
+static void invert_keys(struct test_key *keys, int size)
+{
+	struct static_key *previous = NULL;
+	int i;
+
+	for (i = 0; i < size; i++) {
+		if (previous != keys[i].key) {
+			invert_key(keys[i].key);
+			previous = keys[i].key;
+		}
+	}
+}
+
+int verify_keys(struct test_key *keys, int size, bool invert)
+{
+	int i;
+	bool ret, init;
+
+	for (i = 0; i < size; i++) {
+		ret = static_key_enabled(keys[i].key);
+		init = keys[i].init_state;
+		if (ret != (invert ? !init : init))
+			return -EINVAL;
+		ret = keys[i].test_key();
+		if (static_key_enabled(keys[i].key)) {
+			if (!ret)
+				return -EINVAL;
+		} else {
+			if (ret)
+				return -EINVAL;
+		}
+	}
+	return 0;
+}
+
+static int __init test_static_key_init(void)
+{
+	int ret;
+	int size;
+
+	struct test_key static_key_tests[] = {
+		/* internal keys - old keys */
+		{
+			.init_state	= true,
+			.key		= &old_true_key,
+			.test_key	= test_key_func(&old_true_key, static_key_true),
+		},
+		{
+			.init_state	= false,
+			.key		= &old_false_key,
+			.test_key	= test_key_func(&old_false_key, static_key_false),
+		},
+		/* internal keys - new keys */
+		{
+			.init_state	= true,
+			.key		= &true_key.key,
+			.test_key	= test_key_func(&true_key, static_branch_likely),
+		},
+		{
+			.init_state	= true,
+			.key		= &true_key.key,
+			.test_key	= test_key_func(&true_key, static_branch_unlikely),
+		},
+		{
+			.init_state	= false,
+			.key		= &false_key.key,
+			.test_key	= test_key_func(&false_key, static_branch_likely),
+		},
+		{
+			.init_state	= false,
+			.key		= &false_key.key,
+			.test_key	= test_key_func(&false_key, static_branch_unlikely),
+		},
+		/* external keys - old keys */
+		{
+			.init_state	= true,
+			.key		= &base_old_true_key,
+			.test_key	= test_key_func(&base_old_true_key, static_key_true),
+		},
+		{
+			.init_state	= false,
+			.key		= &base_inv_old_true_key,
+			.test_key	= test_key_func(&base_inv_old_true_key, static_key_true),
+		},
+		{
+			.init_state	= false,
+			.key		= &base_old_false_key,
+			.test_key	= test_key_func(&base_old_false_key, static_key_false),
+		},
+		{
+			.init_state	= true,
+			.key		= &base_inv_old_false_key,
+			.test_key	= test_key_func(&base_inv_old_false_key, static_key_false),
+		},
+		/* external keys - new keys */
+		{
+			.init_state	= true,
+			.key		= &base_true_key.key,
+			.test_key	= test_key_func(&base_true_key, static_branch_likely),
+		},
+		{
+			.init_state	= true,
+			.key		= &base_true_key.key,
+			.test_key	= test_key_func(&base_true_key, static_branch_unlikely),
+		},
+		{
+			.init_state	= false,
+			.key		= &base_inv_true_key.key,
+			.test_key	= test_key_func(&base_inv_true_key, static_branch_likely),
+		},
+		{
+			.init_state	= false,
+			.key		= &base_inv_true_key.key,
+			.test_key	= test_key_func(&base_inv_true_key, static_branch_unlikely),
+		},
+		{
+			.init_state	= false,
+			.key		= &base_false_key.key,
+			.test_key	= test_key_func(&base_false_key, static_branch_likely),
+		},
+		{
+			.init_state	= false,
+			.key		= &base_false_key.key,
+			.test_key	= test_key_func(&base_false_key, static_branch_unlikely),
+		},
+		{
+			.init_state	= true,
+			.key		= &base_inv_false_key.key,
+			.test_key	= test_key_func(&base_inv_false_key, static_branch_likely),
+		},
+		{
+			.init_state	= true,
+			.key		= &base_inv_false_key.key,
+			.test_key	= test_key_func(&base_inv_false_key, static_branch_unlikely),
+		},
+	};
+
+	size = ARRAY_SIZE(static_key_tests);
+
+	ret = verify_keys(static_key_tests, size, false);
+	if (ret)
+		goto out;
+
+	invert_keys(static_key_tests, size);
+	ret = verify_keys(static_key_tests, size, true);
+	if (ret)
+		goto out;
+
+	invert_keys(static_key_tests, size);
+	ret = verify_keys(static_key_tests, size, false);
+	if (ret)
+		goto out;
+	return 0;
+out:
+	return ret;
+}
+
+static void __exit test_static_key_exit(void)
+{
+}
+
+module_init(test_static_key_init);
+module_exit(test_static_key_exit);
+
+MODULE_AUTHOR("Jason Baron <jbaron@akamai.com>");
+MODULE_LICENSE("GPL");

tools/testing/selftests/jumplabel/test_jump_label.sh

@@ -1,16 +0,0 @@
-#!/bin/sh
-# Runs jump label kernel module tests
-
-if /sbin/modprobe -q test_jump_label_base; then
-	if /sbin/modprobe -q test_jump_label; then
-		echo "jump_label: ok"
-		/sbin/modprobe -q -r test_jump_label
-		/sbin/modprobe -q -r test_jump_label_base
-	else
-		echo "jump_label: [FAIL]"
-		/sbin/modprobe -q -r test_jump_label_base
-	fi
-else
-	echo "jump_label: [FAIL]"
-	exit 1
-fi

tools/testing/selftests/static_keys/Makefile

@@ -1,8 +1,8 @@
-# Makefile for jump label selftests
+# Makefile for static keys selftests
 
 # No binaries, but make sure arg-less "make" doesn't trigger "run_tests"
 all:
 
-TEST_PROGS := test_jump_label.sh
+TEST_PROGS := test_static_keys.sh
 
 include ../lib.mk

tools/testing/selftests/static_keys/test_static_keys.sh

@@ -0,0 +1,16 @@
+#!/bin/sh
+# Runs static keys kernel module tests
+
+if /sbin/modprobe -q test_static_key_base; then
+	if /sbin/modprobe -q test_static_keys; then
+		echo "static_key: ok"
+		/sbin/modprobe -q -r test_static_keys
+		/sbin/modprobe -q -r test_static_key_base
+	else
+		echo "static_keys: [FAIL]"
+		/sbin/modprobe -q -r test_static_key_base
+	fi
+else
+	echo "static_key: [FAIL]"
+	exit 1
+fi