Commit 579e1acb authored by Jason Baron's avatar Jason Baron Committed by Ingo Molnar

jump_label: Provide a self-test

Signed-off-by: default avatarJason Baron <jbaron@akamai.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
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: shuahkh@osg.samsung.com
Cc: vbabka@suse.cz
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/0c091ecebd78a879ed8a71835d205a691a75ab4e.1438227999.git.jbaron@akamai.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent ed79e946
......@@ -1841,6 +1841,15 @@ config MEMTEST
memtest=17, mean do 17 test patterns.
If you are unsure how to answer this question, answer N.
config TEST_JUMP_LABEL
tristate "Test jump label"
default n
depends on m
help
Test jump labels.
If unsure, say N.
source "samples/Kconfig"
source "lib/Kconfig.kgdb"
......
......@@ -39,6 +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_JUMP_LABEL) += test_jump_label_base.o
ifeq ($(CONFIG_DEBUG_KOBJECT),y)
CFLAGS_kobject.o += -DDEBUG
......
/*
* 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");
/*
* 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 base_old_true_key = STATIC_KEY_INIT_TRUE;
EXPORT_SYMBOL_GPL(base_old_true_key);
struct static_key base_inv_old_true_key = STATIC_KEY_INIT_TRUE;
EXPORT_SYMBOL_GPL(base_inv_old_true_key);
struct static_key base_old_false_key = STATIC_KEY_INIT_FALSE;
EXPORT_SYMBOL_GPL(base_old_false_key);
struct static_key base_inv_old_false_key = STATIC_KEY_INIT_FALSE;
EXPORT_SYMBOL_GPL(base_inv_old_false_key);
/* new keys */
DEFINE_STATIC_KEY_TRUE(base_true_key);
EXPORT_SYMBOL_GPL(base_true_key);
DEFINE_STATIC_KEY_TRUE(base_inv_true_key);
EXPORT_SYMBOL_GPL(base_inv_true_key);
DEFINE_STATIC_KEY_FALSE(base_false_key);
EXPORT_SYMBOL_GPL(base_false_key);
DEFINE_STATIC_KEY_FALSE(base_inv_false_key);
EXPORT_SYMBOL_GPL(base_inv_false_key);
static void invert_key(struct static_key *key)
{
if (static_key_enabled(key))
static_key_disable(key);
else
static_key_enable(key);
}
static int __init test_jump_label_base_init(void)
{
invert_key(&base_inv_old_true_key);
invert_key(&base_inv_old_false_key);
invert_key(&base_inv_true_key.key);
invert_key(&base_inv_false_key.key);
return 0;
}
static void __exit test_jump_label_base_exit(void)
{
}
module_init(test_jump_label_base_init);
module_exit(test_jump_label_base_exit);
MODULE_AUTHOR("Jason Baron <jbaron@akamai.com>");
MODULE_LICENSE("GPL");
......@@ -20,6 +20,7 @@ ifneq (1, $(quicktest))
TARGETS += timers
endif
TARGETS += user
TARGETS += jumplabel
TARGETS += vm
TARGETS += x86
#Please keep the TARGETS list alphabetically sorted
......
# Makefile for jump label selftests
# No binaries, but make sure arg-less "make" doesn't trigger "run_tests"
all:
TEST_PROGS := test_jump_label.sh
include ../lib.mk
#!/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
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment