This adds new functions for futex operations, starting with wait,
abstimed_wait, reltimed_wait, wake. They add documentation and error
checking according to the current draft of the Linux kernel futex manpage.
Waiting with absolute or relative timeouts is split into separate functions.
This allows for removing a few cases of code duplication in pthreads code,
which uses absolute timeouts; also, it allows us to put platform-specific
code to go from an absolute to a relative timeout into the platform-specific
futex abstractions..
Futex operations that can be canceled are also split out into separate
functions suffixed by "_cancelable".
There are separate versions for both Linux and NaCl; while they currently
differ only slightly, my expectation is that the separate versions of
lowlevellock-futex.h will eventually be merged into futex-internal.h
when we get to move the lll_ functions over to the new futex API.
Some pthreads functions use getrlimit and gettimeofday, but these
functions are XSI, not base POSIX; this is a namespace issue for
dynamic linking as well as static linking. This patch makes them use
__getrlimit and __gettimeofday instead - the former needed to be newly
exported from libc.so at GLIBC_PRIVATE (and so now needs
libc_hidden_proto / libc_hidden_def), the latter was already exported.
Tested for x86_64 (testsuite, and that disassembly of installed shared
libraries is unchanged by the patch).
[BZ #17682]
* resource/Versions (libc): Add __getrlimit at GLIBC_PRIVATE.
* resource/getrlimit.c (__getrlimit): Use libc_hidden_def.
* sysdeps/mach/hurd/getrlimit.c (__getrlimit): Likewise.
* include/sys/resource.h (__getrlimit): Use libc_hidden_proto.
* nptl/nptl-init.c (__pthread_initialize_minimal_internal): Use
__getrlimit instead of getrlimit.
* nptl/pthread_cond_timedwait.c (__pthread_cond_timedwait): Use
__gettimeofday instead of gettimeofday.
* nptl/pthread_rwlock_timedrdlock.c (pthread_rwlock_timedrdlock):
Likewise.
* nptl/pthread_rwlock_timedwrlock.c (pthread_rwlock_timedwrlock):
Likewise.
* sysdeps/pthread/aio_misc.c (handle_fildes_io): Likewise.
* conform/Makefile (test-xfail-POSIX2008/aio.h/linknamespace):
Remove variable.
(test-xfail-POSIX2008/pthread.h/linknamespace): Likewise.
(test-xfail-POSIX2008/time.h/linknamespace): Likewise.
If a call to the set*id functions fails in a multi-threaded program,
the abort introduced in commit 13f7fe35ae
was triggered.
We address by checking that all calls to set*id on all threads give
the same result, and only abort if we see success followed by failure
(or vice versa).
At this point, we can only abort the process because we have already
switched credentials on other threads. Returning an error would still
leave the process in an inconsistent state.
The new xtest needs root privileges to run.
This patch introduces two new convenience functions to set the default
thread attributes used for creating threads. This allows a programmer
to set the default thread attributes just once in a process and then
run pthread_create without additional attributes.
This reverts the change that allows the POSIX Thread default stack size
to be changed by the environment variable
GLIBC_PTHREAD_DEFAULT_STACKSIZE. It has been requested that more
discussion happen before this change goes into 2.18.
