The exact timer ID allocation mode is used by CRIU to restore timers with a
given ID. Add a test case for it.
It's skipped on older kernels when the prctl() fails.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/all/8734fl2tkx.ffs@tglx
Remove local NSEC_PER_SEC and USEC_PER_SEC defines. Pick them up from
include/vdso/time64.h. This requires -I $(top_srcdir) to the timers
Makefile to include the include/vdso/time64.h.
posix_timers test names the defines NSECS_PER_SEC and USECS_PER_SEC.
Change posix_timers test references to the defines to match the
defines in the header file.
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Acked-by: John Stultz <jstultz@google.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
__fatal_error routine doesn't check strerror_r() return value,
which results in the following compile time warning:
posix_timers.c: In function ‘__fatal_error’:
posix_timers.c:31:9: warning: ignoring return value of ‘strerror_r’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
31 | strerror_r(errno, buf, sizeof(buf));
Fix this by adding a check for return value and error handling appropriate
for the GNU-specific strerror_r() in use in __fatal_error(). Check if
return string is null and handle accordingly.
From Linux strerror_r() manual page:
"The GNU-specific strerror_r() returns a pointer to a string containing
the error message. This may be either a pointer to a string that the
function stores in buf, or a pointer to some (immutable) static string
(in which case buf is unused). If the function stores a string in buf,
then at most buflen bytes are stored (the string may be truncated if
buflen is too small and errnum is unknown). The string always includes
a terminating null byte."
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Acked-by: John Stultz <jstultz@google.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
When a timer signal is blocked and later unblocked then one signal should
be delivered with the correct number of overruns since the timer was queued.
Validate that behaviour.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
timer_gettime() must return the correct expiry time for interval timers
even when the timer is not armed, which is the case when a signal is
pending but blocked.
Works correctly for regular posix timers, but not for posix CPU timers.
Add a selftest to validate the fixes.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Posix timers with a delivery mode of SIGEV_NONE deliver no signals but the
remaining expiry time must be readable via timer_gettime() for both one
shot and interval timers.
That's implemented correctly for regular posix timers but broken for posix
CPU timers.
Add a self test so the fixes can be verified.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Add a test case to validate correct behaviour vs. timer reprogramming and
deletion.
The handling of queued signals in case of timer reprogramming or deletion
is inconsistent at best.
POSIX does not really specify the behaviour for that:
- "The effect of disarming or resetting a timer with pending expiration
notifications is unspecified."
- "The disposition of pending signals for the deleted timer is
unspecified."
In both cases it is reasonable to expect that pending signals are
discarded. Especially in the reprogramming case it does not make sense to
account for previous overruns or to deliver a signal for a timer which
has been disarmed.
Add tests to validate that no unexpected signals are delivered. They fail
for now until the signal and posix timer code is updated.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Add a test case to validate correct behaviour vs. SIG_IGN.
The posix specification states:
"Setting a signal action to SIG_IGN for a signal that is pending shall
cause the pending signal to be discarded, whether or not it is blocked."
The kernel implements this in the signal handling code, but due to the way
how posix timers are handling SIG_IGN for periodic timers, the behaviour
after installing a real handler again is inconsistent and suprising.
The following sequence is expected to deliver a signal:
install_handler(SIG);
block_signal(SIG);
timer_create(...); <- Should send SIG
timer_settime(value=100ms, interval=100ms);
sleep(1); <- Timer expires and queues signal, timer is not rearmed
as that should happen in the signal delivery path
ignore_signal(SIG); <- Discards queued signal
install_handler(SIG); <- Restore handler, should rearm but does not
sleep(1);
unblock_signal(SIG); <- Should deliver one signal with overrun count
set in siginfo
This fails because nothing rearms the timer when the signal handler is
restored. Add a test for this case which fails until the signal and posix
timer code is fixed.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
No point in returning to main() on fatal errors. Just exit right away.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
After commit f7d5bcd35d ("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 <usama.anjum@collabora.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
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: 0bc4b0cf15 ("selftests: add basic posix timers selftests")
Signed-off-by: John Stultz <jstultz@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240410232637.4135564-3-jstultz@google.com
After commit 6d029c25b7 ("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: 6d029c25b7 ("selftests/timers/posix_timers: Reimplement check_timer_distribution()")
Signed-off-by: John Stultz <jstultz@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Justin Stitt <justinstitt@google.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240410232637.4135564-1-jstultz@google.com
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 bcb7ee7902
("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 bcb7ee7902 ("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: e797203fb3 ("selftests/timers/posix_timers: Test delivery of signals across threads")
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240409133802.GD29396@redhat.com
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 <broonie@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
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 <dvyukov@google.com>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230316123028.2890338-2-elver@google.com
Based on 1 normalized pattern(s):
licensed under the terms of the gnu gpl license version 2
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 62 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.929121379@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In order to work, the 'err' return value has to be updated otherwise the
test can never be true.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
The posix_timers.c test has a loop that tries to keep it in
kernel space, repeatedly calling brk(). However, it doesn't
check the return value, which causes warnings.
This patch adds a err value which captures the return value
and modifies the test so it will quit if a failure occurs.
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Tested-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
The err variable is intended to receive the timer_create() return before
checking it
Signed-off-by: Felipe Pena <felipensp@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add some initial basic tests on a few posix timers interface such as
setitimer() and timer_settime().
These simply check that expiration happens in a reasonable timeframe after
expected elapsed clock time (user time, user + system time, real time,
...).
This is helpful for finding basic breakages while hacking
on this subsystem.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
Cc: Olivier Langlois <olivier@trillion01.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
