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
Since htl does not actually need a stack switch, we can initialize it
like nptl is, avoiding all sorts of startup issues with ifunc.
More precisely, htl defines __pthread_initialize_minimal instead of the
elder _cthread_init_routine. We can then drop the stack switching dances.
Like hurd_thread_cancel does.
* sysdeps/mach/hurd/htl/pt-docancel.c: Include <hurd/signal.h>
(__pthread_do_cancel): Lock target thread's critical_section_lock and ss
lock around thread mangling.
* sysdeps/htl/pthreadP.h: Include <link.h>
(__pthread_init_static_tls): New prototype.
* htl/pt-alloc.c (__pthread_init_static_tls): New function.
* sysdeps/mach/hurd/htl/pt-sysdep.c (_init_routine): Initialize tcb
field of initial thread. Set GL(dl_init_static_tls) to
&__pthread_init_static_tls.
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.
900778283a ("htl: make pthread_spin_lock really spin") made
pthread_spin_lock really spin and not block, but the current users of
__pthread_spin_lock were assuming that it blocks, i.e. they use it as a
lightweight mutex fitting in just one int.
__pthread_spin_wait provides that support back.
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>
This adds _hurd_sigstate_set_global_rcv used by libpthread to enable
POSIX-confirming behavior of signals on a per-thread basis.
This also provides a sigstate destructor _hurd_sigstate_delete, and a
global process signal state, which needs to be locked and check when
global disposition is enabled, thus the addition of _hurd_sigstate_lock
_hurd_sigstate_actions _hurd_sigstate_pending _hurd_sigstate_unlock helpers.
This also updates all the glibc code accordingly.
This also drops support for get_int(INIT_SIGMASK), which did not make sense
any more since we do not have a single signal thread any more.
During fork/spawn, this also reinitializes the child global sigstate's
lock. That cures an issue that would very rarely cause a deadlock in the
child in fork, tries to unlock ss' critical section lock at the end of
fork. This will typically (always?) be observed in /bin/sh, which is not
surprising as that is the foremost caller of fork.
To reproduce an intermediate state, add an endless loop if
_hurd_global_sigstate is locked after __proc_dostop (cast through
volatile); that is, while still being in the fork's parent process.
When that triggers (use the libtool testsuite), the signal thread has
already locked ss (which is _hurd_global_sigstate), and is stuck at
hurdsig.c:685 in post_signal, trying to lock _hurd_siglock (which the
main thread already has locked and keeps locked until after
__task_create). This is the case that ss->thread == MACH_PORT_NULL, that
is, a global signal. In the main thread, between __proc_dostop and
__task_create is the __thread_abort call on the signal thread which would
abort any current kernel operation (but leave ss locked). Later in fork,
in the parent, when _hurd_siglock is unlocked in fork, the parent's
signal thread can proceed and will unlock eventually the global sigstate.
In the client, _hurd_siglock will likewise be unlocked, but the global
sigstate never will be, as the client's signal thread has been configured
to restart execution from _hurd_msgport_receive. Thus, when the child
tries to unlock ss' critical section lock at the end of fork, it will
first lock the global sigstate, will spin trying to lock it, which can
never be successful, and we get our deadlock.
Options seem to be:
* Move the locking of _hurd_siglock earlier in post_signal -- but that
may generally impact performance, if this locking isn't generally
needed anyway?
On the other hand, would it actually make sense to wait here until we
are not any longer in a critical section (which is meant to disable
signal delivery anyway (but not for preempted signals?))?
* Clear the global sigstate in the fork's child with the rationale that
we're anyway restarting the signal thread from a clean state. This
has now been implemented.
Why has this problem not been observed before Jérémie's patches? (Or has
it? Perhaps even more rarely?) In _S_msg_sig_post, the signal is now
posted to a *global receiver thread*, whereas previously it was posted to
the *designated signal-receiving thread*. The latter one was in a
critical section in fork, so didn't try to handle the signal until after
leaving the critical section? (Not completely analyzed and verified.)
Another question is what the signal is that is being received
during/around the time __proc_dostop executes.
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
* htl/cthreads-compat.c (__cthread_detach): Call __pthread_detach
instead of pthread_detach.
(__cthread_fork): Call __pthread_create instead of pthread_create.
(__cthread_keycreate): Call __pthread_key_create instead of
pthread_key_create.
(__cthread_getspecific): Call __pthread_getspecific instead of
pthread_getspecific.
(__cthread_setspecific): Call __pthread_setspecific instead of
pthread_setspecific.
* htl/pt-alloc.c (__pthread_alloc): Call __pthread_mutex_lock and
__pthread_mutex_unlock instead of pthread_mutex_lock and
pthread_mutex_unlock.
* htl/pt-cleanup.c (__pthread_get_cleanup_stack): Rename to
___pthread_get_cleanup_stack.
(__pthread_get_cleanup_stack): New strong alias.
* htl/pt-create.c: Include <pthreadP.h>.
(entry_point): Call __pthread_exit instead of pthread_exit.
(pthread_create): Rename to __pthread_create.
(pthread_create): New strong alias.
* htl/pt-detach.c (pthread_detach): Rename to __pthread_detach.
(pthread_detach): New strong alias.
(__pthread_detach): Call __pthread_cond_broadcast instead of
pthread_cond_broadcast.
* htl/pt-exit.c (__pthread_exit): Call __pthread_setcancelstate
instead of pthread_setcancelstate.
* htl/pt-testcancel.c: Include <pthreadP.h>.
(pthread_testcancel): Call __pthread_exit instead of pthread_exit.
* sysdeps/htl/pt-attr-getstack.c: Include <pthreadP.h>
(__pthread_attr_getstack): Call __pthread_attr_getstackaddr and
__pthread_attr_getstacksize instead of pthread_attr_getstackaddr and
pthread_attr_getstacksize.
* sysdeps/htl/pt-attr-getstackaddr.c (pthread_attr_getstackaddr):
Rename to __pthread_attr_getstackaddr.
(pthread_attr_getstackaddr): New strong alias.
* sysdeps/htl/pt-attr-getstacksize.c (pthread_attr_getstacksize):
Rename to __pthread_attr_getstacksize.
(pthread_attr_getstacksize): New strong alias.
* sysdeps/htl/pt-attr-setstack.c: Include <pthreadP.h>.
(pthread_attr_setstack): Rename to __pthread_attr_setstack.
(pthread_attr_setstack): New strong alias.
(__pthread_attr_setstack): Call __pthread_attr_getstacksize,
__pthread_attr_setstacksize and __pthread_attr_setstackaddr instead of
pthread_attr_getstacksize, pthread_attr_setstacksize and
pthread_attr_setstackaddr.
* sysdeps/htl/pt-attr-setstackaddr.c (pthread_attr_setstackaddr):
Rename to __pthread_attr_setstackaddr.
(pthread_attr_setstackaddr): New strong alias.
* sysdeps/htl/pt-attr-setstacksize.c (pthread_attr_setstacksize):
Rename to __pthread_attr_setstacksize.
(pthread_attr_setstacksize): New strong alias.
* sysdeps/htl/pt-cond-timedwait.c: Include <pthreadP.h>.
(__pthread_cond_timedwait_internal): Use __pthread_exit instead of
pthread_exit.
* sysdeps/htl/pt-key-create.c: Include <pthreadP.h>.
(__pthread_key_create): New hidden def.
* sysdeps/htl/pt-key.h: Include <pthreadP.h>.
* sysdeps/htl/pthreadP.h (_pthread_mutex_init,
__pthread_cond_broadcast, __pthread_create, __pthread_detach,
__pthread_exit, __pthread_key_create, __pthread_getspecific,
__pthread_setspecific, __pthread_setcancelstate,
__pthread_attr_getstackaddr, __pthread_attr_setstackaddr,
__pthread_attr_getstacksize, __pthread_attr_setstacksize,
__pthread_attr_setstack, ___pthread_get_cleanup_stack): New
declarations.
(__pthread_key_create, _pthread_mutex_init): New hidden declarations.
* sysdeps/mach/hurd/htl/pt-attr-setstackaddr.c
(pthread_attr_setstackaddr): Rename to __pthread_attr_setstackaddr.
(pthread_attr_setstackaddr): New strong alias.
* sysdeps/mach/hurd/htl/pt-attr-setstacksize.c
(pthread_attr_setstacksize): Rename to __pthread_attr_setstacksize.
(pthread_attr_setstacksize): New strong alias.
* sysdeps/mach/hurd/htl/pt-docancel.c: Include <pthreadP.h>.
(call_exit): Call __pthread_exit instead of pthread_exit.
* sysdeps/mach/hurd/htl/pt-mutex-init.c: Include <pthreadP.h>.
(_pthread_mutex_init): New hidden definition.
* sysdeps/mach/hurd/htl/pt-sysdep.c: Include <pthreadP.h>.
(_init_routine): Call __pthread_attr_init and __pthread_attr_setstack
instead of pthread_attr_init and pthread_attr_setstack.
Contributed by
Agustina Arzille <avarzille@riseup.net>
Amos Jeffries <squid3@treenet.co.nz>
David Michael <fedora.dm0@gmail.com>
Marco Gerards <marco@gnu.org>
Marcus Brinkmann <marcus@gnu.org>
Neal H. Walfield <neal@gnu.org>
Pino Toscano <toscano.pino@tiscali.it>
Richard Braun <rbraun@sceen.net>
Roland McGrath <roland@gnu.org>
Samuel Thibault <samuel.thibault@ens-lyon.org>
Thomas DiModica <ricinwich@yahoo.com>
Thomas Schwinge <tschwinge@gnu.org>
* htl: New directory.
* sysdeps/htl: New directory.
* sysdeps/hurd/htl: New directory.
* sysdeps/i386/htl: New directory.
* sysdeps/mach/htl: New directory.
* sysdeps/mach/hurd/htl: New directory.
* sysdeps/mach/hurd/i386/htl: New directory.
* nscd/Depend, resolv/Depend, rt/Depend: Add htl dependency.
* sysdeps/mach/hurd/i386/Implies: Add mach/hurd/i386/htl imply.
* sysdeps/mach/hurd/i386/libpthread.abilist: New file.
