This is another attempt at making pthread_once handle throwing exceptions
from the init routine callback. As the new testcases show, just switching
to the cleanup attribute based cleanup does fix the tst-once5 test, but
breaks the new tst-oncey3 test. That is because when throwing exceptions,
only the unwind info registered cleanups (i.e. C++ destructors or cleanup
attribute), when cancelling threads and there has been unwind info from the
cancellation point up to whatever needs cleanup both unwind info registered
cleanups and THREAD_SETMEM (self, cleanup, ...) registered cleanups are
invoked, but once we hit some frame with no unwind info, only the
THREAD_SETMEM (self, cleanup, ...) registered cleanups are invoked.
So, to stay fully backwards compatible (allow init routines without
unwind info which encounter cancellation points) and handle exception throwing
we actually need to register the pthread_once cleanups in both unwind info
and in the THREAD_SETMEM (self, cleanup, ...) way.
If an exception is thrown, only the former will happen and we in that case
need to also unregister the THREAD_SETMEM (self, cleanup, ...) registered
handler, because otherwise after catching the exception the user code could
call deeper into the stack some cancellation point, get cancelled and then
a stale cleanup handler would clobber stack and probably crash.
If a thread calling init routine is cancelled and unwind info ends before
the pthread_once frame, it will be cleaned up through self->cleanup as
before. And if unwind info is present, unwind_stop first calls the
self->cleanup registered handler for the frame, then it will call the
unwind info registered handler but that will already see __do_it == 0
and do nothing.
The elision interfaces are closely aligned between the targets that
implement them, so declare them in the generic <lowlevellock.h>
file.
Empty .c stubs are provided, so that fewer makefile updates
under sysdeps are needed. Also simplify initialization via
__libc_early_init.
The symbols __lll_clocklock_elision, __lll_lock_elision,
__lll_trylock_elision, __lll_unlock_elision, __pthread_force_elision
move into libc. For the time being, non-hidden references are used
from libpthread to access them, but once that part of libpthread
is moved into libc, hidden symbols will be used again. (Hidden
references seem desirable to reduce the likelihood of transactions
aborts.)
Take in consideration the trailling NULL since sem_search uses
strcmp to compare entries.
Checked on x86_64-linux-gnu and powerpc-linux-gnu (where it triggered
a nptl/tst-sem7 regression).
sem_open already returns EINVAL for input names larger than NAME_MAX,
so it can assume the largest name length with tfind.
Checked on x86_64-linux-gnu.
The internal semaphore list code is moved to a specific file,
sem_routine.c, and the internal usage is simplified to only two
functions (one to insert a new semaphore and one to remove it
from the internal list). There is no need to expose the
internal locking, neither how the semaphore mapping is implemented.
No functional or semantic change is expected, tested on
x86_64-linux-gnu.
Previously, glibc would pick an arbitrary tmpfs file system from
/proc/mounts if /dev/shm was not available. This could lead to
an unsuitable file system being picked for the backing storage for
shm_open, sem_open, and related functions.
This patch introduces a new function, __shm_get_name, which builds
the file name under the appropriate (now hard-coded) directory. It is
called from the various shm_* and sem_* function. Unlike the
SHM_GET_NAME macro it replaces, the callers handle the return values
and errno updates. shm-directory.c is moved directly into the posix
subdirectory because it can be implemented directly using POSIX
functionality. It resides in libc because it is needed by both
librt and nptl/htl.
In the sem_open implementation, tmpfname is initialized directly
from a string constant. This happens to remove one alloca call.
Checked on x86_64-linux-gnu.
I used these shell commands:
../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")
and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 6694 files FOO.
I then removed trailing white space from benchtests/bench-pthread-locks.c
and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this
diagnostic from Savannah:
remote: *** pre-commit check failed ...
remote: *** error: lines with trailing whitespace found
remote: error: hook declined to update refs/heads/master
The aio_suspend function has been converted to support 64 bit time.
This change uses (in aio_misc.h):
- __futex_abstimed_wait64 (instead of futex_reltimed_wait)
- __futex_abstimed_wait_cancellable64
(instead of futex_reltimed_wait_cancellable)
from ./sysdeps/nptl/futex-helpers.h
The aio_suspend() accepts relative timeout, which then is converted to
absolute one.
The i686-gnu port (HURD) do not define DONT_NEED_AIO_MISC_COND and as it
doesn't (yet) support 64 bit time it uses not converted
pthread_cond_timedwait().
The __aio_suspend() is supposed to be run on ports with __TIMESIZE !=64 and
__WORDSIZE==32. It internally utilizes __aio_suspend_time64() and hence the
conversion from 32 bit struct timespec to 64 bit one is required.
For ports supporting 64 bit time the __aio_suspend_time64() will be used
either via alias (to __aio_suspend when __TIMESIZE==64) or redirection
(when -D_TIME_BITS=64 is passed).
Build tests:
./src/scripts/build-many-glibcs.py glibcs
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The 878fe624d4 changed lll_futex_timed_wait, which expects a relative
timeout, with a __futex_abstimed_wait64, which expects an absolute
timeout. However the code still passes a relative timeout.
Also, the PTHREAD_PRIO_PROTECT support for clocks different than
CLOCK_REALTIME was broken since the inclusion of
pthread_mutex_clocklock (9d20e22e46) since lll_futex_timed_wait
always use CLOCK_REALTIME.
This patch fixes by removing the relative time calculation. It
also adds some xtests that tests both thread and inter-process
usage.
Checked on x86_64-linux-gnu.
The align the GNU extension with the others one that accept specify
which clock to wait for (such as pthread_mutex_clocklock).
Check on x86_64-linux-gnu.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
Linux futex FUTEX_LOCK_PI operation only supports CLOCK_REALTIME,
so pthread_mutex_clocklock operation with priority aware mutexes
may fail depending of the input timeout.
Also, it is not possible to convert a CLOCK_MONOTONIC to a
CLOCK_REALTIME due the possible wall clock time change which might
invalid the requested timeout.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
- tst-mtx-recursive.c: mtx_init fails to use mtx_plain. Per C11
specs, using mtx_recursive alone is not supported. This isn't
catched because mtx_plain is defined as 0.
- tst-thrd-sleep.c: thrd_sleep returns 0 on success, a negative
value on failure. Testing against thrd_success is incorrect.
- tst-tss-basic.c: tss_set is incorrectly checkd for a non-0
value. The test should test aginst C11 threads error codes.
This isn't catched because thrd_success is defined as 0.
Note that all three tests fail on FreeBSD, which defines all mutex type
values, as well as all C11 threads error codes with non-0 values.
By aligning its implementation on pthread_cond_wait.
* sysdeps/htl/sem-timedwait.c (cancel_ctx): New structure.
(cancel_hook): New function.
(__sem_timedwait_internal): Check for cancellation and register
cancellation hook that wakes the thread up, and check again for
cancellation on exit.
* nptl/tst-cancel13.c, nptl/tst-cancelx13.c: Move to...
* sysdeps/pthread/: ... here.
* nptl/Makefile: Move corresponding references and rules to...
* sysdeps/pthread/Makefile: ... here.
* nptl/tst-cancel25.c: Move to...
* sysdeps/pthread/tst-cancel25.c: ... here.
(tf2) Do not test for SIGCANCEL when it is not defined.
* nptl/Makefile: Move corresponding reference to...
* sysdeps/pthread/Makefile: ... here.
d6d74ec16 ('htl: Enable more tests') moved the linking rules from
nptl/Makefile and htl/Makefile to the shared sysdeps/pthread/Makefile. But
e.g. on powerpc some tests are added in sysdeps/powerpc/Makefile, which is
included *after* sysdeps/pthread/Makefile, and thus the tests don't get
affected by the rules and fail to link. For now let's just copy over the
set of rules in both nptl/Makefile and htl/Makefile.
* sysdeps/pthread/Makefile: Move libpthread linking rules to...
* htl/Makefile: ... here and...
* nptl/Makefile: ... there.
This allows to reuse the storage after calling pthread_cond_destroy.
* sysdeps/htl/bits/types/struct___pthread_cond.h (__pthread_cond):
Replace unused struct __pthread_condimpl *__impl field with unsigned int
__wrefs.
(__PTHREAD_COND_INITIALIZER): Update accordingly.
* sysdeps/htl/pt-cond-timedwait.c (__pthread_cond_timedwait_internal):
Register as waiter in __wrefs field. On unregistering, wake any pending
pthread_cond_destroy.
* sysdeps/htl/pt-cond-destroy.c (__pthread_cond_destroy): Register wake
request in __wrefs.
* nptl/Makefile (tests): Move tst-cond20 tst-cond21 to...
* sysdeps/pthread/Makefile (tests): ... here.
* nptl/tst-cond20.c nptl/tst-cond21.c: Move to...
* sysdeps/pthread/tst-cond20.c sysdeps/pthread/tst-cond21.c: ... here.
so it gets shared by nptl and htl. Also add htl versions of thrd_current and
thrd_yield.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Since gettimeofday will shortly be implemented in terms of
clock_gettime on all platforms, internal code should use clock_gettime
directly; in addition to removing a layer of indirection, this will
allow us to remove the PLT-bypass gunk for gettimeofday. (We can't
quite do that yet, but it'll be coming later in this patch series.)
In many cases, the changed code does fewer conversions.
The changed code always assumes __clock_gettime (CLOCK_REALTIME)
cannot fail. Most of the call sites were assuming gettimeofday could
not fail, but a few places were checking for errors. POSIX says
clock_gettime can only fail if the clock constant is invalid or
unsupported, and CLOCK_REALTIME is the one and only clock constant
that's required to be supported. For consistency I grepped the entire
source tree for any other places that checked for errors from
__clock_gettime (CLOCK_REALTIME), found one, and changed it too.
(For the record, POSIX also says gettimeofday can never fail.)
(It would be nice if we could declare that GNU systems will always
support CLOCK_MONOTONIC as well as CLOCK_REALTIME; there are several
places where we are using CLOCK_REALTIME where _MONOTONIC would be
more appropriate, and/or trying to use _MONOTONIC and then falling
back to _REALTIME. But the Hurd doesn't support CLOCK_MONOTONIC yet,
and it looks like adding it would involve substantial changes to
gnumach's internals and API. Oh well.)
A few Hurd-specific files were changed to use __host_get_time instead
of __clock_gettime, as this seemed tidier. We also assume this cannot
fail. Skimming the code in gnumach leads me to believe the only way
it could fail is if __mach_host_self also failed, and our
Hurd-specific code consistently assumes that can't happen, so I'm
going with that.
With the exception of support/support_test_main.c, test cases are not
modified, mainly because I didn't want to have to figure out which
test cases were testing gettimeofday specifically.
The definition of GETTIME in sysdeps/generic/memusage.h had a typo and
was not reading tv_sec at all. I fixed this. It appears nobody has been
generating malloc traces on a machine that doesn't have a superseding
definition.
There are a whole bunch of places where the code could be simplified
by factoring out timespec subtraction and/or comparison logic, but I
want to keep this patch as mechanical as possible.
Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc64le-linux-gnu,
powerpc64-linux-gnu, powerpc-linux-gnu, and aarch64-linux-gnu.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Lukasz Majewski <lukma@denx.de>
The valid_nanoseconds () static inline function has been introduced to
check if nanoseconds value is in the correct range - greater or equal to
zero and less than 1000000000.
The explicit #include <time.h> has been added to files where it was
missing.
The __syscall_slong_t type for ns has been used to avoid issues on x32.
Tested with:
- scripts/build-many-glibcs.py
- make PARALLELMFLAGS="-j12" && make PARALLELMFLAGS="-j12" xcheck on x86_64
