[v4] syscalls/membarrier: Add membarrier() initial test

Message ID 20181008132914.8246-1-rafael.tinoco@linaro.org
State New
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Series
  • [v4] syscalls/membarrier: Add membarrier() initial test
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Commit Message

Rafael David Tinoco Oct. 8, 2018, 1:29 p.m.
Fixes: #265

Initial test for membarrier() syscall. It tests all existing membarrier
"commands" (or features), including the need (or not) for previous
registration for the call to work.

Some features did not exist in older kernels and that is covered by
skipping some calls, flagging test as skipped & okay, and forcing
others, making sure that return codes and errno are set right in those
cases.

Tests are done in a child process due to inexistent kernel interface to
"unregister" the process from being affected by membarrier() call.

Signed-off-by: Rafael David Tinoco <rafael.tinoco@linaro.org>
---
 configure.ac                                  |   1 +
 include/lapi/membarrier.h                     |  30 ++
 include/lapi/syscalls/aarch64.in              |   1 +
 include/lapi/syscalls/arm.in                  |   1 +
 include/lapi/syscalls/hppa.in                 |   1 +
 include/lapi/syscalls/i386.in                 |   1 +
 include/lapi/syscalls/ia64.in                 |   1 +
 include/lapi/syscalls/powerpc.in              |   1 +
 include/lapi/syscalls/powerpc64.in            |   1 +
 include/lapi/syscalls/s390.in                 |   1 +
 include/lapi/syscalls/s390x.in                |   1 +
 include/lapi/syscalls/sparc.in                |   1 +
 include/lapi/syscalls/sparc64.in              |   1 +
 include/lapi/syscalls/x86_64.in               |   1 +
 runtest/syscalls                              |   2 +
 .../kernel/syscalls/membarrier/.gitignore     |   1 +
 testcases/kernel/syscalls/membarrier/Makefile |   8 +
 .../kernel/syscalls/membarrier/membarrier01.c | 418 ++++++++++++++++++
 18 files changed, 472 insertions(+)
 create mode 100644 include/lapi/membarrier.h
 create mode 100644 testcases/kernel/syscalls/membarrier/.gitignore
 create mode 100644 testcases/kernel/syscalls/membarrier/Makefile
 create mode 100644 testcases/kernel/syscalls/membarrier/membarrier01.c

Comments

Jan Stancek Oct. 8, 2018, 2:07 p.m. | #1
----- Original Message -----
> Fixes: #265
> 
> Initial test for membarrier() syscall. It tests all existing membarrier
> "commands" (or features), including the need (or not) for previous
> registration for the call to work.
> 
> Some features did not exist in older kernels and that is covered by
> skipping some calls, flagging test as skipped & okay, and forcing
> others, making sure that return codes and errno are set right in those
> cases.
> 
> Tests are done in a child process due to inexistent kernel interface to
> "unregister" the process from being affected by membarrier() call.
> 
> Signed-off-by: Rafael David Tinoco <rafael.tinoco@linaro.org>

Looks good to me.

We probably can drop linux/membarrier.h configure check, right?
(since v4 doesn't include it and unsupported kernel should
hit ENOSYS and TCONF)

Regards,
Jan
Rafael David Tinoco Oct. 8, 2018, 2:13 p.m. | #2
On 10/8/18 11:07 AM, Jan Stancek wrote:
> 
> 
> ----- Original Message -----
>> Fixes: #265
>>
>> Initial test for membarrier() syscall. It tests all existing membarrier
>> "commands" (or features), including the need (or not) for previous
>> registration for the call to work.
>>
>> Some features did not exist in older kernels and that is covered by
>> skipping some calls, flagging test as skipped & okay, and forcing
>> others, making sure that return codes and errno are set right in those
>> cases.
>>
>> Tests are done in a child process due to inexistent kernel interface to
>> "unregister" the process from being affected by membarrier() call.
>>
>> Signed-off-by: Rafael David Tinoco <rafael.tinoco@linaro.org>
> 
> Looks good to me.
> 
> We probably can drop linux/membarrier.h configure check, right?
> (since v4 doesn't include it and unsupported kernel should
> hit ENOSYS and TCONF)

Ooops, true. No need to check HAVE_LINUX_MEMBARRIER_H if we are 
declaring all CMDs and will be given ENOSYS. Want me to send a v5 ?

> Regards,
> Jan
>
Jan Stancek Oct. 8, 2018, 2:25 p.m. | #3
----- Original Message -----
> On 10/8/18 11:07 AM, Jan Stancek wrote:
> > 
> > 
> > ----- Original Message -----
> >> Fixes: #265
> >>
> >> Initial test for membarrier() syscall. It tests all existing membarrier
> >> "commands" (or features), including the need (or not) for previous
> >> registration for the call to work.
> >>
> >> Some features did not exist in older kernels and that is covered by
> >> skipping some calls, flagging test as skipped & okay, and forcing
> >> others, making sure that return codes and errno are set right in those
> >> cases.
> >>
> >> Tests are done in a child process due to inexistent kernel interface to
> >> "unregister" the process from being affected by membarrier() call.
> >>
> >> Signed-off-by: Rafael David Tinoco <rafael.tinoco@linaro.org>
> > 
> > Looks good to me.
> > 
> > We probably can drop linux/membarrier.h configure check, right?
> > (since v4 doesn't include it and unsupported kernel should
> > hit ENOSYS and TCONF)
> 
> Ooops, true. No need to check HAVE_LINUX_MEMBARRIER_H if we are
> declaring all CMDs and will be given ENOSYS. Want me to send a v5 ?

Let's give a couple days to other potential reviewers. If nothing
else comes up, I can drop it before push.

Thanks,
Jan
Rafael David Tinoco Oct. 8, 2018, 2:43 p.m. | #4
On 10/8/18 11:25 AM, Jan Stancek wrote:
>>> Looks good to me.
>>>
>>> We probably can drop linux/membarrier.h configure check, right?
>>> (since v4 doesn't include it and unsupported kernel should
>>> hit ENOSYS and TCONF)

>> Ooops, true. No need to check HAVE_LINUX_MEMBARRIER_H if we are
>> declaring all CMDs and will be given ENOSYS. Want me to send a v5 ?

> Let's give a couple days to other potential reviewers. If nothing
> else comes up, I can drop it before push.

Thanks a lot for reviewing this.

Best,
Rafael
Jan Stancek Oct. 11, 2018, 9:06 a.m. | #5
----- Original Message -----
> On 10/8/18 11:25 AM, Jan Stancek wrote:
> >>> Looks good to me.
> >>>
> >>> We probably can drop linux/membarrier.h configure check, right?
> >>> (since v4 doesn't include it and unsupported kernel should
> >>> hit ENOSYS and TCONF)
> 
> >> Ooops, true. No need to check HAVE_LINUX_MEMBARRIER_H if we are
> >> declaring all CMDs and will be given ENOSYS. Want me to send a v5 ?
> 
> > Let's give a couple days to other potential reviewers. If nothing
> > else comes up, I can drop it before push.
> 
> Thanks a lot for reviewing this.

Pushed.

Regards,
Jan

Patch

diff --git a/configure.ac b/configure.ac
index e1ecb32a7..98425f997 100644
--- a/configure.ac
+++ b/configure.ac
@@ -45,6 +45,7 @@  AC_CHECK_HEADERS([ \
     linux/mempolicy.h \
     linux/module.h \
     linux/netlink.h \
+    linux/membarrier.h \
     mm.h \
     netinet/sctp.h \
     pthread.h \
diff --git a/include/lapi/membarrier.h b/include/lapi/membarrier.h
new file mode 100644
index 000000000..2b6c57fb3
--- /dev/null
+++ b/include/lapi/membarrier.h
@@ -0,0 +1,30 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2018 Linaro Limited. All rights reserved.
+ * Author: Rafael David Tinoco <rafael.tinoco@linaro.org>
+ */
+
+#ifndef LAPI_MEMBARRIER_H
+#define LAPI_MEMBARRIER_H
+
+/*
+ * Having <linux/membarrier.h> is enough to know if the test should run or
+ * not, but it might not define all needed MEMBARRIER_CMD_* being tested,
+ * since its first versions included just a few commands.
+ */
+
+enum membarrier_cmd {
+	MEMBARRIER_CMD_QUERY					= 0,
+	MEMBARRIER_CMD_GLOBAL					= (1 << 0),
+	MEMBARRIER_CMD_GLOBAL_EXPEDITED				= (1 << 1),
+	MEMBARRIER_CMD_REGISTER_GLOBAL_EXPEDITED		= (1 << 2),
+	MEMBARRIER_CMD_PRIVATE_EXPEDITED			= (1 << 3),
+	MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED		= (1 << 4),
+	MEMBARRIER_CMD_PRIVATE_EXPEDITED_SYNC_CORE		= (1 << 5),
+	MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED_SYNC_CORE	= (1 << 6),
+
+	/* Alias for header backward compatibility. */
+	MEMBARRIER_CMD_SHARED			= MEMBARRIER_CMD_GLOBAL,
+};
+
+#endif
diff --git a/include/lapi/syscalls/aarch64.in b/include/lapi/syscalls/aarch64.in
index 9ac7f997b..f6b0b2949 100644
--- a/include/lapi/syscalls/aarch64.in
+++ b/include/lapi/syscalls/aarch64.in
@@ -256,6 +256,7 @@  sendmmsg 269
 kcmp 272
 getrandom 278
 memfd_create 279
+membarrier 283
 mlock2 284
 copy_file_range 285
 _sysctl 1078
diff --git a/include/lapi/syscalls/arm.in b/include/lapi/syscalls/arm.in
index 0a7f98ac5..d8897b180 100644
--- a/include/lapi/syscalls/arm.in
+++ b/include/lapi/syscalls/arm.in
@@ -341,6 +341,7 @@  renameat2 (__NR_SYSCALL_BASE+382)
 getrandom (__NR_SYSCALL_BASE+384)
 memfd_create (__NR_SYSCALL_BASE+385)
 execveat (__NR_SYSCALL_BASE+387)
+membarrier (__NR_SYSCALL_BASE+389)
 mlock2 (__NR_SYSCALL_BASE+390)
 copy_file_range (__NR_SYSCALL_BASE+391)
 statx (__NR_SYSCALL_BASE+397)
diff --git a/include/lapi/syscalls/hppa.in b/include/lapi/syscalls/hppa.in
index 3db978069..e961dabe3 100644
--- a/include/lapi/syscalls/hppa.in
+++ b/include/lapi/syscalls/hppa.in
@@ -17,5 +17,6 @@  splice 291
 tee 293
 vmsplice 294
 memfd_create 340
+membarrier 343
 mlock2 345
 copy_file_range 346
diff --git a/include/lapi/syscalls/i386.in b/include/lapi/syscalls/i386.in
index a000564d2..2a6df8bda 100644
--- a/include/lapi/syscalls/i386.in
+++ b/include/lapi/syscalls/i386.in
@@ -341,6 +341,7 @@  renameat2 354
 getrandom 355
 memfd_create 356
 execveat 358
+membarrier 375
 mlock2 376
 copy_file_range 377
 statx 383
diff --git a/include/lapi/syscalls/ia64.in b/include/lapi/syscalls/ia64.in
index 278819387..02f86d7d3 100644
--- a/include/lapi/syscalls/ia64.in
+++ b/include/lapi/syscalls/ia64.in
@@ -296,5 +296,6 @@  prlimit64 1325
 renameat2 1338
 getrandom 1339
 memfd_create 1340
+membarrier 1344
 mlock2 1346
 copy_file_range 1347
diff --git a/include/lapi/syscalls/powerpc.in b/include/lapi/syscalls/powerpc.in
index c0b4226eb..e8e5acb3b 100644
--- a/include/lapi/syscalls/powerpc.in
+++ b/include/lapi/syscalls/powerpc.in
@@ -347,6 +347,7 @@  sched_getattr 356
 renameat2 357
 getrandom 359
 memfd_create 360
+membarrier 365
 mlock2 378
 copy_file_range 379
 statx 383
diff --git a/include/lapi/syscalls/powerpc64.in b/include/lapi/syscalls/powerpc64.in
index c0b4226eb..e8e5acb3b 100644
--- a/include/lapi/syscalls/powerpc64.in
+++ b/include/lapi/syscalls/powerpc64.in
@@ -347,6 +347,7 @@  sched_getattr 356
 renameat2 357
 getrandom 359
 memfd_create 360
+membarrier 365
 mlock2 378
 copy_file_range 379
 statx 383
diff --git a/include/lapi/syscalls/s390.in b/include/lapi/syscalls/s390.in
index 47a04de27..8f0ba9278 100644
--- a/include/lapi/syscalls/s390.in
+++ b/include/lapi/syscalls/s390.in
@@ -331,6 +331,7 @@  sched_getattr 346
 renameat2 347
 getrandom 349
 memfd_create 350
+membarrier 356
 execveat 354
 mlock2 374
 copy_file_range 375
diff --git a/include/lapi/syscalls/s390x.in b/include/lapi/syscalls/s390x.in
index 83732ffbe..4fe69f41e 100644
--- a/include/lapi/syscalls/s390x.in
+++ b/include/lapi/syscalls/s390x.in
@@ -331,5 +331,6 @@  sched_getattr 346
 renameat2 347
 getrandom 349
 memfd_create 350
+membarrier 356
 mlock2 374
 copy_file_range 375
diff --git a/include/lapi/syscalls/sparc.in b/include/lapi/syscalls/sparc.in
index 2b06a797a..e611ffae8 100644
--- a/include/lapi/syscalls/sparc.in
+++ b/include/lapi/syscalls/sparc.in
@@ -336,5 +336,6 @@  kcmp 341
 renameat2 345
 getrandom 347
 memfd_create 348
+membarrier 351
 mlock2 356
 copy_file_range 357
diff --git a/include/lapi/syscalls/sparc64.in b/include/lapi/syscalls/sparc64.in
index 8c8a86673..9794078e4 100644
--- a/include/lapi/syscalls/sparc64.in
+++ b/include/lapi/syscalls/sparc64.in
@@ -312,5 +312,6 @@  kcmp 341
 renameat2 345
 getrandom 347
 memfd_create 348
+membarrier 351
 mlock2 356
 copy_file_range 357
diff --git a/include/lapi/syscalls/x86_64.in b/include/lapi/syscalls/x86_64.in
index 4ce8477de..9a1832114 100644
--- a/include/lapi/syscalls/x86_64.in
+++ b/include/lapi/syscalls/x86_64.in
@@ -308,6 +308,7 @@  renameat2 316
 getrandom 318
 memfd_create 319
 execveat 322
+membarrier 324
 mlock2 325
 copy_file_range 326
 statx 332
diff --git a/runtest/syscalls b/runtest/syscalls
index 0d0be7713..19be14098 100644
--- a/runtest/syscalls
+++ b/runtest/syscalls
@@ -1504,3 +1504,5 @@  statx02 statx02
 statx03 statx03
 statx04 statx04
 statx05 statx05
+
+membarrier01 membarrier01
diff --git a/testcases/kernel/syscalls/membarrier/.gitignore b/testcases/kernel/syscalls/membarrier/.gitignore
new file mode 100644
index 000000000..eec8058b9
--- /dev/null
+++ b/testcases/kernel/syscalls/membarrier/.gitignore
@@ -0,0 +1 @@ 
+/membarrier01
diff --git a/testcases/kernel/syscalls/membarrier/Makefile b/testcases/kernel/syscalls/membarrier/Makefile
new file mode 100644
index 000000000..f71e4fc25
--- /dev/null
+++ b/testcases/kernel/syscalls/membarrier/Makefile
@@ -0,0 +1,8 @@ 
+# Copyright (c) 2018 - Linaro Limited. All rights reserved.
+# SPDX-License-Identifier: GPL-2.0-or-later
+
+top_srcdir		?= ../../../..
+
+include $(top_srcdir)/include/mk/testcases.mk
+
+include $(top_srcdir)/include/mk/generic_leaf_target.mk
\ No newline at end of file
diff --git a/testcases/kernel/syscalls/membarrier/membarrier01.c b/testcases/kernel/syscalls/membarrier/membarrier01.c
new file mode 100644
index 000000000..cb5ef0a76
--- /dev/null
+++ b/testcases/kernel/syscalls/membarrier/membarrier01.c
@@ -0,0 +1,418 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2018 Linaro Limited. All rights reserved.
+ * Author: Rafael David Tinoco <rafael.tinoco@linaro.org>
+ */
+/*
+ * Basic tests for membarrier(2) syscall. Tests below are responsible for
+ * testing the membarrier(2) interface only, without checking if the barrier
+ * was successful or not. Check test_case structure for each test description.
+ */
+
+#include "config.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+#include <syscall.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "tst_test.h"
+#include "lapi/syscalls.h"
+#include "lapi/membarrier.h"
+
+#ifdef HAVE_LINUX_MEMBARRIER_H
+
+struct test_case {
+	char testname[80];
+	int command;		/* membarrier cmd                            */
+	int needregister;	/* membarrier cmd needs register cmd	     */
+	int flags;		/* flags for given membarrier cmd	     */
+	long exp_ret;		/* expected return code for given cmd        */
+	int exp_errno;		/* expected errno for given cmd failure      */
+	int enabled;		/* enabled, despite results from CMD_QUERY   */
+	int always;		/* CMD_QUERY should always enable this test  */
+	int force;		/* force if CMD_QUERY reports not enabled    */
+	int force_exp_errno;	/* expected errno after forced cmd           */
+	int change_exp_errno;	/* previous kernels forced errno result      */
+	int change_kernver[3];	/* kernel version having diff expected errno */
+};
+
+struct test_case tc[] = {
+	{
+	 /*
+	  * case 00) invalid cmd
+	  *     - enabled by default
+	  *     - should always fail with EINVAL
+	  */
+	 .testname = "cmd_fail",
+	 .command = -1,
+	 .exp_ret = -1,
+	 .exp_errno = EINVAL,
+	 .enabled = 1,
+	 },
+	{
+	 /*
+	  * case 01) invalid flags
+	  *     - enabled by default
+	  *     - should always fail with EINVAL
+	  */
+	 .testname = "cmd_flags_fail",
+	 .command = MEMBARRIER_CMD_QUERY,
+	 .flags = 1,
+	 .exp_ret = -1,
+	 .exp_errno = EINVAL,
+	 .enabled = 1,
+	 },
+	{
+	 /*
+	  * case 02) global barrier
+	  *     - should ALWAYS be enabled by CMD_QUERY
+	  *     - should always succeed
+	  */
+	 .testname = "cmd_global_success",
+	 .command = MEMBARRIER_CMD_GLOBAL,
+	 .flags = 0,
+	 .exp_ret = 0,
+	 .always = 1,
+	 },
+	 /*
+	  * commit 22e4ebb975 (v4.14-rc1) added cases 03, 04 and 05 features:
+	  */
+	{
+	 /*
+	  * case 03) private expedited barrier with no registrations
+	  *     - should fail with errno=EPERM due to no registrations
+	  *     - or be skipped if unsupported by running kernel
+	  */
+	 .testname = "cmd_private_expedited_fail",
+	 .command = MEMBARRIER_CMD_PRIVATE_EXPEDITED,
+	 .flags = 0,
+	 .exp_ret = -1,
+	 .exp_errno = EPERM,
+	 },
+	{
+	 /*
+	  * case 04) register private expedited
+	  *     - should succeed when supported by running kernel
+	  *     - or fail with errno=EINVAL if unsupported and forced
+	  */
+	 .testname = "cmd_private_expedited_register_success",
+	 .command = MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED,
+	 .flags = 0,
+	 .exp_ret = 0,
+	 .force = 1,
+	 .force_exp_errno = EINVAL,
+	 },
+	{
+	 /*
+	  * case 05) private expedited barrier with registration
+	  *     - should succeed due to existing registration
+	  *     - or fail with errno=EINVAL if unsupported and forced
+	  *     - NOTE: commit 70216e18e5 (v4.16-rc1) changed behavior:
+	  *     -       (a) if unsupported, and forced, < 4.16 , errno is EINVAL
+	  *     -       (b) if unsupported, and forced, >= 4.16, errno is EPERM
+	  */
+	 .testname = "cmd_private_expedited_success",
+	 .needregister = MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED,
+	 .command = MEMBARRIER_CMD_PRIVATE_EXPEDITED,
+	 .flags = 0,
+	 .exp_ret = 0,
+	 .force = 1,
+	 .force_exp_errno = EPERM,
+	 .change_exp_errno = EINVAL,
+	 .change_kernver = { 4, 16, 0 },
+	 },
+	 /*
+	  * commit 70216e18e5 (v4.16-rc1) added cases 06, 07 and 08 features:
+	  */
+	{
+	 /*
+	  * case 06) private expedited sync core barrier with no registrations
+	  *     - should fail with errno=EPERM due to no registrations
+	  *     - or be skipped if unsupported by running kernel
+	  */
+	 .testname = "cmd_private_expedited_sync_core_fail",
+	 .command = MEMBARRIER_CMD_PRIVATE_EXPEDITED_SYNC_CORE,
+	 .flags = 0,
+	 .exp_ret = -1,
+	 .exp_errno = EPERM,
+	 },
+	{
+	 /*
+	  * case 07) register private expedited sync core
+	  *     - should succeed when supported by running kernel
+	  *     - or fail with errno=EINVAL if unsupported and forced
+	  */
+	 .testname = "cmd_private_expedited_sync_core_register_success",
+	 .command = MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED_SYNC_CORE,
+	 .flags = 0,
+	 .exp_ret = 0,
+	 .force = 1,
+	 .force_exp_errno = EINVAL,
+	 },
+	{
+	 /*
+	  * case 08) private expedited sync core barrier with registration
+	  *     - should succeed due to existing registration
+	  *     - or fail with errno=EINVAL if unsupported and forced
+	  */
+	 .testname = "cmd_private_expedited_sync_core_success",
+	 .needregister = MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED_SYNC_CORE,
+	 .command = MEMBARRIER_CMD_PRIVATE_EXPEDITED_SYNC_CORE,
+	 .flags = 0,
+	 .exp_ret = 0,
+	 .force = 1,
+	 .force_exp_errno = EINVAL,
+	 },
+	 /*
+	  * commit c5f58bd58f4 (v4.16-rc1) added cases 09, 10 and 11 features:
+	  */
+	{
+	 /*
+	  * case 09) global expedited barrier with no registrations
+	  *     - should never fail due to no registrations
+	  *     - or be skipped if unsupported by running kernel
+	  */
+	 .testname = "cmd_global_expedited_success",
+	 .command = MEMBARRIER_CMD_GLOBAL_EXPEDITED,
+	 .flags = 0,
+	 .exp_ret = 0,
+	 },
+	{
+	 /*
+	  * case 10) register global expedited
+	  *     - should succeed when supported by running kernel
+	  *     - or fail with errno=EINVAL if unsupported and forced
+	  */
+	 .testname = "cmd_global_expedited_register_success",
+	 .command = MEMBARRIER_CMD_REGISTER_GLOBAL_EXPEDITED,
+	 .flags = 0,
+	 .exp_ret = 0,
+	 .force = 1,
+	 .force_exp_errno = EINVAL,
+	 },
+	{
+	 /*
+	  * case 11) global expedited barrier with registration
+	  *     - should also succeed with registrations
+	  *     - or fail with errno=EINVAL if unsupported and forced
+	  */
+	 .testname = "cmd_global_expedited_success",
+	 .needregister = MEMBARRIER_CMD_REGISTER_GLOBAL_EXPEDITED,
+	 .command = MEMBARRIER_CMD_GLOBAL_EXPEDITED,
+	 .flags = 0,
+	 .exp_ret = 0,
+	 .force = 1,
+	 .force_exp_errno = EINVAL,
+	 },
+};
+
+#define passed_ok(_test)						       \
+	do {								       \
+		tst_res(TPASS, "membarrier(2): %s passed", _test.testname);    \
+		return;							       \
+	} while (0)
+
+#define passed_unexpec(_test)						       \
+	do {								       \
+		tst_res(TFAIL, "membarrier(2): %s passed unexpectedly. "       \
+			"ret = %ld with errno %d were expected. (force: %d)",  \
+			_test.testname, _test.exp_ret, _test.exp_errno,        \
+			_test.force);					       \
+		return;							       \
+	} while (0)
+
+#define failed_ok(_test)						       \
+	do {								       \
+		tst_res(TPASS, "membarrier(2): %s failed as expected",	       \
+			_test.testname);				       \
+		return;							       \
+	} while (0)
+
+#define failed_ok_unsupported(_test)					       \
+	do {								       \
+		tst_res(TPASS, "membarrier(2): %s failed as expected "	       \
+			"(unsupported)", _test.testname);		       \
+		return;							       \
+	} while (0)
+
+#define failed_not_ok(_test, _gotret, _goterr)				       \
+	do {								       \
+		tst_res(TFAIL, "membarrier(2): %s failed. "		       \
+			"ret = %ld when expected was %ld. "		       \
+			"errno = %d when expected was %d. (force: %d)",        \
+			_test.testname, _gotret, _test.exp_ret, _goterr,       \
+			_test.exp_errno, _test.force);			       \
+		return;							       \
+	} while (0)
+
+#define failed_unexpec(_test, _gotret, _goterr) 			       \
+	do {								       \
+		tst_res(TFAIL, "membarrier(2): %s failed unexpectedly. "       \
+			"Got ret = %ld with errno %d. (force: %d)",	       \
+			_test.testname, _gotret, _goterr, _test.force);	       \
+		return;							       \
+	} while (0)
+
+#define skipped(_test)							       \
+	do {								       \
+		tst_res(TPASS, "membarrier(2): %s skipped (unsupported)",      \
+			_test.testname);				       \
+		return;							       \
+	} while (0)
+
+#define skipped_fail(_test)						       \
+	do {								       \
+		tst_res(TFAIL, "membarrier(2): %s reported as not supported",  \
+			_test.testname);				       \
+		return;							       \
+	} while (0)
+
+static int sys_membarrier(int cmd, int flags)
+{
+	return tst_syscall(__NR_membarrier, cmd, flags);
+}
+
+static void verify_membarrier(unsigned int i)
+{
+	int ret;
+
+	/* not enabled and not enforced: test is skipped */
+
+	if (!tc[i].enabled && !tc[i].force) {
+
+		if (tc[i].always == 0)
+			skipped(tc[i]);
+
+		skipped_fail(tc[i]);
+	}
+
+	/* iterations: registration needed for some cases */
+
+	if (tc[i].needregister && tc[i].enabled) {
+		ret = sys_membarrier(tc[i].needregister, 0);
+		if (ret < 0) {
+			tst_brk(TBROK, "membarrier(2): %s could not register",
+					tc[i].testname);
+		}
+	}
+
+	TEST(sys_membarrier(tc[i].command, tc[i].flags));
+
+	/* enabled and not enforced: regular expected results only */
+
+	if (tc[i].enabled && !tc[i].force) {
+
+		if (TST_RET >= 0 && tc[i].exp_ret == TST_RET)
+			passed_ok(tc[i]);
+
+		if (TST_RET < 0) {
+			if (tc[i].exp_ret == TST_RET)
+				failed_ok(tc[i]);
+			else
+				failed_not_ok(tc[i], TST_RET, TST_ERR);
+		}
+	}
+
+	/* not enabled and enforced: failure and expected errors */
+
+	if (!tc[i].enabled && tc[i].force) {
+
+		if (TST_RET >= 0)
+			passed_unexpec(tc[i]);
+
+		if (TST_RET < 0) {
+			if (tc[i].force_exp_errno == TST_ERR)
+				failed_ok_unsupported(tc[i]);
+			else
+				failed_unexpec(tc[i], TST_RET, TST_ERR);
+		}
+	}
+
+	/* enabled and enforced: tricky */
+
+	if (tc[i].enabled && tc[i].force) {
+
+		if (TST_RET >= 0) {
+			if (tc[i].exp_ret == TST_RET)
+				passed_ok(tc[i]);
+			else
+				passed_unexpec(tc[i]);
+		}
+
+		if (TST_RET < 0) {
+
+			if (tc[i].exp_ret == TST_RET) {
+
+				if (tc[i].exp_errno == TST_ERR)
+					failed_ok(tc[i]);
+				else
+					failed_unexpec(tc[i], TST_RET, TST_ERR);
+			}
+
+			/* unknown on force failure if enabled and forced */
+			failed_unexpec(tc[i], TST_RET, TST_ERR);
+		}
+	}
+}
+
+static void wrap_verify_membarrier(unsigned int i)
+{
+	pid_t pid;
+
+	/*
+	 * The Linux kernel does not provide a way to unregister the process
+	 * (mm->membarrier_state) intent of being affected by the membarrier(2)
+	 * system call, thus the need of having a wrapper to fork() a child.
+	 */
+
+	pid = SAFE_FORK();
+
+	if (pid)
+		SAFE_WAITPID(pid, NULL, 0);
+	else
+		verify_membarrier(i);
+}
+
+static void setup(void)
+{
+	size_t i;
+	int ret;
+
+	ret = sys_membarrier(MEMBARRIER_CMD_QUERY, 0);
+	if (ret < 0) {
+		if (errno == ENOSYS)
+			tst_brk(TBROK, "membarrier(2): not supported");
+	}
+
+	for (i = 0; i < ARRAY_SIZE(tc); i++) {
+		if ((tc[i].command > 0) && (ret & tc[i].command))
+			tc[i].enabled = 1;
+
+		/* forcing unsupported command might have different errno */
+
+		if (tc[i].change_exp_errno && tc[i].enabled == 0) {
+			if (tst_kvercmp(tc[i].change_kernver[0],
+					tc[i].change_kernver[1],
+					tc[i].change_kernver[2]) < 0)
+				tc[i].force_exp_errno = tc[i].change_exp_errno;
+		}
+	}
+}
+
+static struct tst_test test = {
+	.setup = setup,
+	.test = wrap_verify_membarrier,
+	.tcnt = ARRAY_SIZE(tc),
+	.min_kver = "4.3.0",	/* commit: 5b25b13ab0 (sys_membarrier(): ...) */
+	.forks_child = 1,
+};
+
+#else /* HAVE_LINUX_MEMBARRIER_H */
+TST_TEST_TCONF("<linux/membarrier.h> does not exist");
+#endif