linux-stable.git/tools/testing/selftests/timers, branch linux-6.10.y

selftests: timers: ksft_exit functions do not return

2024-05-06T19:57:21+00:00

After commit f7d5bcd35d42 ("selftests: kselftest: Mark functions that
unconditionally call exit() as __noreturn"), ksft_exit_...() functions
are marked as __noreturn, which means the return type should not be
'int' but 'void' because they are not returning anything (and never were
since exit() has always been called).

To facilitate updating the return type of these functions, remove
'return' before the calls to ksft_exit_...(), as __noreturn prevents the
compiler from warning that a caller of the ksft_exit functions does not
return a value because the program will terminate upon calling these
functions.

Reviewed-by: Muhammad Usama Anjum 
Reviewed-by: Thomas Gleixner 
Signed-off-by: Nathan Chancellor 
Signed-off-by: Shuah Khan

selftests: timers: Fix abs() warning in posix_timers test

2024-04-12T12:11:15+00:00

Building with clang results in the following warning:

  posix_timers.c:69:6: warning: absolute value function 'abs' given an
      argument of type 'long long' but has parameter of type 'int' which may
      cause truncation of value [-Wabsolute-value]
        if (abs(diff - DELAY * USECS_PER_SEC) > USECS_PER_SEC / 2) {
            ^
So switch to using llabs() instead.

Fixes: 0bc4b0cf1570 ("selftests: add basic posix timers selftests")
Signed-off-by: John Stultz 
Signed-off-by: Thomas Gleixner 
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240410232637.4135564-3-jstultz@google.com

selftests: timers: Fix posix_timers ksft_print_msg() warning

2024-04-12T12:11:15+00:00

After commit 6d029c25b71f ("selftests/timers/posix_timers: Reimplement
check_timer_distribution()") the following warning occurs when building
with an older gcc:

posix_timers.c:250:2: warning: format not a string literal and no format arguments [-Wformat-security]
  250 |  ksft_print_msg(errmsg);
      |  ^~~~~~~~~~~~~~

Fix this up by changing it to ksft_print_msg("%s", errmsg)

Fixes: 6d029c25b71f ("selftests/timers/posix_timers: Reimplement check_timer_distribution()")
Signed-off-by: John Stultz 
Signed-off-by: Thomas Gleixner 
Acked-by: Justin Stitt 
Acked-by: Shuah Khan 
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240410232637.4135564-1-jstultz@google.com

selftests: timers: Fix valid-adjtimex signed left-shift undefined behavior

2024-04-10T20:07:42+00:00

The struct adjtimex freq field takes a signed value who's units are in
shifted (<<16) parts-per-million.

Unfortunately for negative adjustments, the straightforward use of:

  freq = ppm << 16 trips undefined behavior warnings with clang:

valid-adjtimex.c:66:6: warning: shifting a negative signed value is undefined [-Wshift-negative-value]
        -499<<16,
        ~~~~^
valid-adjtimex.c:67:6: warning: shifting a negative signed value is undefined [-Wshift-negative-value]
        -450<<16,
        ~~~~^
..

Fix it by using a multiply by (1 << 16) instead of shifting negative values
in the valid-adjtimex test case. Align the values for better readability.

Reported-by: Lee Jones 
Reported-by: Muhammad Usama Anjum 
Signed-off-by: John Stultz 
Signed-off-by: Thomas Gleixner 
Reviewed-by: Muhammad Usama Anjum 
Link: https://lore.kernel.org/r/20240409202222.2830476-1-jstultz@google.com
Link: https://lore.kernel.org/lkml/0c6d4f0d-2064-4444-986b-1d1ed782135f@collabora.com/

selftests/timers/posix_timers: Reimplement check_timer_distribution()

2024-04-09T15:48:19+00:00

check_timer_distribution() runs ten threads in a busy loop and tries to
test that the kernel distributes a process posix CPU timer signal to every
thread over time.

There is not guarantee that this is true even after commit bcb7ee79029d
("posix-timers: Prefer delivery of signals to the current thread") because
that commit only avoids waking up the sleeping process leader thread, but
that has nothing to do with the actual signal delivery.

As the signal is process wide the first thread which observes sigpending
and wins the race to lock sighand will deliver the signal. Testing shows
that this hangs on a regular base because some threads never win the race.

The comment "This primarily tests that the kernel does not favour any one."
is wrong. The kernel does favour a thread which hits the timer interrupt
when CLOCK_PROCESS_CPUTIME_ID expires.

Rewrite the test so it only checks that the group leader sleeping in join()
never receives SIGALRM and the thread which burns CPU cycles receives all
signals.

In older kernels which do not have commit bcb7ee79029d ("posix-timers:
Prefer delivery of signals to the current thread") the test-case fails
immediately, the very 1st tick wakes the leader up. Otherwise it quickly
succeeds after 100 ticks.

CI testing wants to use newer selftest versions on stable kernels. In this
case the test is guaranteed to fail.

So check in the failure case whether the kernel version is less than v6.3
and skip the test result in that case.

[ tglx: Massaged change log, renamed the version check helper ]

Fixes: e797203fb3ba ("selftests/timers/posix_timers: Test delivery of signals across threads")
Signed-off-by: Oleg Nesterov 
Signed-off-by: Thomas Gleixner 
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240409133802.GD29396@redhat.com

selftests: timers: Convert nsleep-lat test to generate KTAP output

2023-10-05T21:00:14+00:00

Currently the nsleep-lat test does not produce KTAP output but rather a
custom format. This means that we only get a pass/fail for the suite, not
for each individual test that the suite does. Convert to using the standard
kselftest output functions which result in KTAP output being generated.

Signed-off-by: Mark Brown 
Signed-off-by: Shuah Khan

selftests: timers: Convert posix_timers test to generate KTAP output

2023-10-05T21:00:07+00:00

Currently the posix_timers test does not produce KTAP output but rather a
custom format. This means that we only get a pass/fail for the suite, not
for each individual test that the suite does. Convert to using the standard
kselftest output functions which result in KTAP output being generated.

As part of this fix the printing of diagnostics in the unlikely event that
the pthread APIs fail, these were using perror() but the API functions
directly return an error code instead of setting errno.

Signed-off-by: Mark Brown 
Signed-off-by: Shuah Khan

tools: timers: fix freq average calculation

2023-07-13T19:32:36+00:00

Delete a duplicate assignment from this function implementation.
The note means ppm is average of the two actual freq samples.
But ppm have a duplicate assignment.

Signed-off-by: Minjie Du 
Acked-by: John Stultz 
Signed-off-by: Shuah Khan

selftests/timers/posix_timers: Test delivery of signals across threads

2023-04-16T07:00:18+00:00

Test that POSIX timers using CLOCK_PROCESS_CPUTIME_ID eventually deliver
a signal to all running threads.  This effectively tests that the kernel
doesn't prefer any one thread (or subset of threads) for signal delivery.

Signed-off-by: Dmitry Vyukov 
Signed-off-by: Marco Elver 
Signed-off-by: Thomas Gleixner 
Link: https://lore.kernel.org/r/20230316123028.2890338-2-elver@google.com

selftests: timers: clocksource-switch: adapt to kselftest framework

2022-07-14T20:36:52+00:00

So we have proper counters at the end of a test. We also print the
kselftest header at the end of the test, so we don't mix with the output
of the child process. There is only this one test anyhow.

Signed-off-by: Wolfram Sang 
Acked-by: John Stultz 
Signed-off-by: Shuah Khan