linux-stable.git/tools/testing/selftests/futex, branch linux-5.15.y

selftests/futex: Define SYS_futex on 32-bit architectures with 64-bit time_t

2025-08-28T14:24:17+00:00

[ Upstream commit 04850819c65c8242072818655d4341e70ae998b5 ]

The kernel does not provide sys_futex() on 32-bit architectures that do not
support 32-bit time representations, such as riscv32.

As a result, glibc cannot define SYS_futex, causing compilation failures in
tests that rely on this syscall. Define SYS_futex as SYS_futex_time64 in
such cases to ensure successful compilation and compatibility.

Signed-off-by: Cynthia Huang 
Signed-off-by: Ben Zong-You Xie 
Signed-off-by: Thomas Gleixner 
Reviewed-by: Muhammad Usama Anjum 
Link: https://lore.kernel.org/all/20250710103630.3156130-1-ben717@andestech.com
Signed-off-by: Sasha Levin

selftests/futex: Order calls to futex_lock_pi

2023-09-19T10:22:31+00:00

[ Upstream commit fbf4dec702774286db409815ffb077711a96b824 ]

Observed occassional failures in the futex_wait_timeout test:

ok 1 futex_wait relative succeeds
ok 2 futex_wait_bitset realtime succeeds
ok 3 futex_wait_bitset monotonic succeeds
ok 4 futex_wait_requeue_pi realtime succeeds
ok 5 futex_wait_requeue_pi monotonic succeeds
not ok 6 futex_lock_pi realtime returned 0
......

The test expects the child thread to complete some steps before
the parent thread gets to run. There is an implicit expectation
of the order of invocation of futex_lock_pi between the child thread
and the parent thread. Make this order explicit. If the order is
not met, the futex_lock_pi call in the parent thread succeeds and
will not timeout.

Fixes: f4addd54b161 ("selftests: futex: Expand timeout test")
Signed-off-by: Nysal Jan K.A 
Signed-off-by: Shuah Khan 
Signed-off-by: Sasha Levin

selftests/futex: fix build for clang

2022-11-26T08:24:30+00:00

[ Upstream commit 03cab65a07e083b6c1010fbc8f9b817e9aca75d9 ]

Don't use the test-specific header files as source files to force a
target dependency, as clang will complain if more than one source file
is used for a compile command with a single '-o' flag.

Use the proper Makefile variables instead as defined in
tools/testing/selftests/lib.mk.

Signed-off-by: Ricardo Cañuelo 
Reviewed-by: André Almeida 
Signed-off-by: Shuah Khan 
Signed-off-by: Sasha Levin

selftests: futex: Use variable MAKE instead of make

2022-02-08T17:34:12+00:00

commit b9199181a9ef8252e47e207be8c23e1f50662620 upstream.

Recursive make commands should always use the variable MAKE, not the
explicit command name ‘make’. This has benefits and removes the
following warning when multiple jobs are used for the build:

make[2]: warning: jobserver unavailable: using -j1.  Add '+' to parent make rule.

Fixes: a8ba798bc8ec ("selftests: enable O and KBUILD_OUTPUT")
Signed-off-by: Muhammad Usama Anjum 
Reviewed-by: André Almeida 
Signed-off-by: Shuah Khan 
Signed-off-by: Greg Kroah-Hartman

selftests: futex: Add futex compare requeue test

2021-06-22T09:20:16+00:00

Add testing for futex_cmp_requeue(). The first test just requeues from one
waiter to another one, and wakes it. The second performs both wake and
requeue, and checks the return values to see if the operation woke/requeued
the expected number of waiters.

Signed-off-by: André Almeida 
Signed-off-by: Thomas Gleixner 
Acked-by: Davidlohr Bueso 
Link: https://lore.kernel.org/r/20210531165036.41468-3-andrealmeid@collabora.com

selftests: futex: Add futex wait test

2021-06-22T09:20:15+00:00

There are three different strategies to uniquely identify a futex in the
kernel:

 - Private futexes: uses the pointer to mm_struct and the page address

 - Shared futexes: checks if the page containing the address is a PageAnon:
   - If it is, uses the same data as a private futexes
   - If it isn't, uses an inode sequence number from struct inode and
      the page's index

Create a selftest to check those three paths and basic wait/wake
mechanism.

Signed-off-by: André Almeida 
Signed-off-by: Thomas Gleixner 
Acked-by: Davidlohr Bueso 
Link: https://lore.kernel.org/r/20210531165036.41468-2-andrealmeid@collabora.com

selftests: futex: Expand timeout test

2021-05-12T18:44:59+00:00

Improve futex timeout testing by checking all the operations that
supports timeout and their available modes.

Signed-off-by: André Almeida 
Signed-off-by: Ingo Molnar 
Link: https://lore.kernel.org/r/20210427135328.11013-3-andrealmeid@collabora.com

selftests: futex: Correctly include headers dirs

2021-05-12T18:44:58+00:00

When building selftests, the build system will install uapi linux
headers at usr/include in kernel source's root directory. When building
with a different output folder, the headers will be installed at
kselftests/usr/include.

Add both paths so we can build the tests using up-to-date headers.

Currently, this is uncommon to happen since it's rare to find a
build system with an outdated futex header, but it happens
when testing new futex operations.

Signed-off-by: André Almeida 
Signed-off-by: Ingo Molnar 
Link: https://lore.kernel.org/r/20210427135328.11013-2-andrealmeid@collabora.com

.gitignore: add SPDX License Identifier

2020-03-25T10:50:48+00:00

Add SPDX License Identifier to all .gitignore files.

Signed-off-by: Masahiro Yamada 
Signed-off-by: Greg Kroah-Hartman

selftests: use LDLIBS for libraries instead of LDFLAGS

2020-02-13T20:14:34+00:00

While building selftests, the following errors were observed:
> tools/testing/selftests/timens'
> gcc -Wall -Werror -pthread  -lrt -ldl  timens.c  -o tools/testing/selftests/timens/timens
> /usr/bin/ld: /tmp/ccGy5CST.o: in function `check_config_posix_timers':
> timens.c:(.text+0x65a): undefined reference to `timer_create'
> collect2: error: ld returned 1 exit status

Quoting commit 870f193d48c2 ("selftests: net: use LDLIBS instead of
LDFLAGS"):

The default Makefile rule looks like:

$(CC) $(CFLAGS) $(LDFLAGS) $@ $^ $(LDLIBS)

When linking is done by gcc itself, no issue, but when it needs to be passed
to proper ld, only LDLIBS follows and then ld cannot know what libs to link
with.

More detail:
https://www.gnu.org/software/make/manual/html_node/Implicit-Variables.html

LDFLAGS
Extra flags to give to compilers when they are supposed to invoke the linker,
‘ld’, such as -L. Libraries (-lfoo) should be added to the LDLIBS variable
instead.

LDLIBS
Library flags or names given to compilers when they are supposed to invoke the
linker, ‘ld’. LOADLIBES is a deprecated (but still supported) alternative to
LDLIBS. Non-library linker flags, such as -L, should go in the LDFLAGS
variable.

While at here, correct other selftests, not only timens ones.

Reported-by: Shuah Khan 
Signed-off-by: Dmitry Safonov 
Tested-by: Shuah Khan 
Signed-off-by: Shuah Khan