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2023-06-02Fix all the remaining misspellings -- BZ 25337Paul Pluzhnikov1-2/+2
2023-01-06Update copyright dates with scripts/update-copyrightsJoseph Myers1-1/+1
2022-01-01Update copyright dates with scripts/update-copyrightsPaul Eggert1-1/+1
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 7061 files FOO. I then removed trailing white space from math/tgmath.h, support/tst-support-open-dev-null-range.c, and sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following obscure pre-commit check failure diagnostics from Savannah. I don't know why I run into these diagnostics whereas others evidently do not. remote: *** 912-#endif remote: *** 913: remote: *** 914- remote: *** error: lines with trailing whitespace found ... remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
2021-09-03Remove "Contributed by" linesSiddhesh Poyarekar1-1/+0
We stopped adding "Contributed by" or similar lines in sources in 2012 in favour of git logs and keeping the Contributors section of the glibc manual up to date. Removing these lines makes the license header a bit more consistent across files and also removes the possibility of error in attribution when license blocks or files are copied across since the contributed-by lines don't actually reflect reality in those cases. Move all "Contributed by" and similar lines (Written by, Test by, etc.) into a new file CONTRIBUTED-BY to retain record of these contributions. These contributors are also mentioned in manual/contrib.texi, so we just maintain this additional record as a courtesy to the earlier developers. The following scripts were used to filter a list of files to edit in place and to clean up the CONTRIBUTED-BY file respectively. These were not added to the glibc sources because they're not expected to be of any use in future given that this is a one time task: https://gist.github.com/siddhesh/b5ecac94eabfd72ed2916d6d8157e7dc https://gist.github.com/siddhesh/15ea1f5e435ace9774f485030695ee02 Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-07-07nptl: Reduce the GLIBC_PRIVATE ABIFlorian Weimer1-2/+3
The remaining symbols are mostly used by libthread_db. __pthread_get_minstack has to remain exported even though unused. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-06-15y2038: Add support for 64-bit time on legacy ABIsAdhemerval Zanella1-6/+3
A new build flag, _TIME_BITS, enables the usage of the newer 64-bit time symbols for legacy ABI (where 32-bit time_t is default). The 64 bit time support is only enabled if LFS (_FILE_OFFSET_BITS=64) is also used. Different than LFS support, the y2038 symbols are added only for the required ABIs (armhf, csky, hppa, i386, m68k, microblaze, mips32, mips64-n32, nios2, powerpc32, sparc32, s390-32, and sh). The ABIs with 64-bit time support are unchanged, both for symbol and types redirection. On Linux the full 64-bit time support requires a minimum of kernel version v5.1. Otherwise, the 32-bit fallbacks are used and might results in error with overflow return code (EOVERFLOW). The i686-gnu does not yet support 64-bit time. This patch exports following rediretions to support 64-bit time: * libc: adjtime adjtimex clock_adjtime clock_getres clock_gettime clock_nanosleep clock_settime cnd_timedwait ctime ctime_r difftime fstat fstatat futimens futimes futimesat getitimer getrusage gettimeofday gmtime gmtime_r localtime localtime_r lstat_time lutimes mktime msgctl mtx_timedlock nanosleep nanosleep ntp_gettime ntp_gettimex ppoll pselec pselect pthread_clockjoin_np pthread_cond_clockwait pthread_cond_timedwait pthread_mutex_clocklock pthread_mutex_timedlock pthread_rwlock_clockrdlock pthread_rwlock_clockwrlock pthread_rwlock_timedrdlock pthread_rwlock_timedwrlock pthread_timedjoin_np recvmmsg sched_rr_get_interval select sem_clockwait semctl semtimedop sem_timedwait setitimer settimeofday shmctl sigtimedwait stat thrd_sleep time timegm timerfd_gettime timerfd_settime timespec_get utime utimensat utimes utimes wait3 wait4 * librt: aio_suspend mq_timedreceive mq_timedsend timer_gettime timer_settime * libanl: gai_suspend Reviewed-by: Lukasz Majewski <lukma@denx.de> Reviewed-by: Carlos O'Donell <carlos@redhat.com> Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-05-19nptl: Add missing __pthread_cond_wait alias in static buildsFlorian Weimer1-0/+3
Fixes commit cf3fff1c195f859ba949a7ad86d4fca70bd99740 ("nptl: Move cnd_wait into libc"). Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
2021-05-03nptl: Move cnd_wait into libcFlorian Weimer1-2/+0
The symbol was moved using scripts/move-symbol-to-libc.py. The __pthread_cond_wait@@GLIBC_PRIVATE symbol is no longer neded, so remove that as well. Reviewed-by: Carlos O'Donell <carlos@redhat.com> Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-05-03nptl: Move cnd_timedwait into libcFlorian Weimer1-4/+6
The symbol was moved using scripts/move-symbol-to-libc.py. The __pthread_cond_timedwait@@GLIBC_PRIVATE symbol is no longer neded, so remove that as well. Reviewed-by: Carlos O'Donell <carlos@redhat.com> Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-04-21nptl: Move core condition variable functions into libcFlorian Weimer1-20/+42
Onl pthread_cond_clockwait did not have a forwarder, so it needs a new symbol version. Some complications arise due to the need to supply hidden aliases, GLIBC_PRIVATE exports (for the C11 condition variable implementation that still remains in libpthread) and 64-bit time_t stubs. pthread_cond_broadcast, pthread_cond_signal, pthread_cond_timedwait, pthread_cond_wait, pthread_cond_clockwait have been moved using scripts/move-symbol-to-libc.py. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-01-04nptl: Fix comment typo in pthread_cond_wait.cJangwoong Kim1-1/+1
2021-01-02Update copyright dates with scripts/update-copyrightsPaul Eggert1-1/+1
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
2020-11-27nptl: Add EOVERFLOW checks for futex callsAdhemerval Zanella1-2/+2
Some futex-internal calls require additional check for EOVERFLOW (as indicated by [1] [2] [3]). For both mutex and rwlock code, EOVERFLOW is handle as ETIMEDOUT; since it indicate to the caller that the blocking operation could not be issued. For mutex it avoids a possible issue where PTHREAD_MUTEX_ROBUST_* might assume EOVERFLOW indicate futex has succeed, and for PTHREAD_MUTEX_PP_* it avoid a potential busy infinite loop. For rwlock and semaphores, it also avoids potential busy infinite loops. Checked on x86_64-linux-gnu and i686-linux-gnu, although EOVERFLOW won't be possible with current usage (since all timeouts on 32-bit architectures with 32-bit time_t support will be in the range of 32-bit time_t). [1] https://sourceware.org/pipermail/libc-alpha/2020-November/120079.html [2] https://sourceware.org/pipermail/libc-alpha/2020-November/120080.html [3] https://sourceware.org/pipermail/libc-alpha/2020-November/120127.html
2020-11-25nptl: Remove futex_wait_cancelableAdhemerval Zanella1-20/+2
It is used solely on __pthread_cond_wait_common and the call can be replaced by a __futex_abstimed_wait_cancelable64 one. Checked on x86_64-linux-gnu and i686-linux-gnu. Reviewed-by: Lukasz Majewski <lukma@denx.de>
2020-09-02y2038: nptl: Convert pthread_cond_{clock|timed}wait to support 64 bit timeLukasz Majewski1-8/+35
The pthread_cond_clockwait and pthread_cond_timedwait have been converted to support 64 bit time. This change introduces new futex_abstimed_wait_cancelable64 function in ./sysdeps/nptl/futex-helpers.c, which uses futex_time64 where possible and tries to replace low-level preprocessor macros from lowlevellock-futex.h The pthread_cond_{clock|timed}wait only accepts absolute time. Moreover, there is no need to check for NULL passed as *abstime pointer as __pthread_cond_wait_common() always passes non-NULL struct __timespec64 pointer to futex_abstimed_wait_cancellable64(). For systems with __TIMESIZE != 64 && __WORDSIZE == 32: - Conversions between 64 bit time to 32 bit are necessary - Redirection to __pthread_cond_{clock|timed}wait64 will provide support for 64 bit time The futex_abstimed_wait_cancelable64 function has been put into a separate file on the purpose - to avoid issues apparent on the m68k architecture related to small number of available registers (there is not enough registers to put all necessary arguments in them if the above function would be added to futex-internal.h with __always_inline attribute). In fact - new function - namely __futex_abstimed_wait_cancellable32 is used to reduce number of needed registers (as some in-register values are stored on the stack when function call is made). Build tests: ./src/scripts/build-many-glibcs.py glibcs Run-time tests: - Run specific tests on ARM/x86 32bit systems (qemu): https://github.com/lmajewski/meta-y2038 and run tests: https://github.com/lmajewski/y2038-tests/commits/master Above tests were performed with Y2038 redirection applied as well as without to test the proper usage of both __pthread_cond_{clock|timed}wait64 and __pthread_cond_{clock|timed}wait. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2020-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers1-1/+1
2019-10-27time: Introduce function to check correctness of nanoseconds valueLukasz Majewski1-2/+2
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
2019-09-07Prefer https to http for gnu.org and fsf.org URLsPaul Eggert1-1/+1
Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g ' \ $(find $(git ls-files) -prune -type f \ ! -name '*.po' \ ! -name 'ChangeLog*' \ ! -path COPYING ! -path COPYING.LIB \ ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \ ! -path manual/texinfo.tex ! -path scripts/config.guess \ ! -path scripts/config.sub ! -path scripts/install-sh \ ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \ ! -path INSTALL ! -path locale/programs/charmap-kw.h \ ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \ ! '(' -name configure \ -execdir test -f configure.ac -o -f configure.in ';' ')' \ ! '(' -name preconfigure \ -execdir test -f preconfigure.ac ';' ')' \ -print) and then by running 'make dist-prepare' to regenerate files built from the altered files, and then executing the following to cleanup: chmod a+x sysdeps/unix/sysv/linux/riscv/configure # Omit irrelevant whitespace and comment-only changes, # perhaps from a slightly-different Autoconf version. git checkout -f \ sysdeps/csky/configure \ sysdeps/hppa/configure \ sysdeps/riscv/configure \ sysdeps/unix/sysv/linux/csky/configure # Omit changes that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines git checkout -f \ sysdeps/powerpc/powerpc64/ppc-mcount.S \ sysdeps/unix/sysv/linux/s390/s390-64/syscall.S # Omit change that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
2019-07-12nptl: Remove futex_supports_exact_relative_timeoutsMike Crowe1-5/+0
The only implementation of futex_supports_exact_relative_timeouts always returns true. Let's remove it and all its callers. * nptl/pthread_cond_wait.c: (__pthread_cond_clockwait): Remove code that is only useful if futex_supports_exact_relative_timeouts () returns false. * nptl/pthread_condattr_setclock.c: (pthread_condattr_setclock): Likewise. * sysdeps/nptl/futex-internal.h: Remove comment about relative timeouts potentially being imprecise since it's no longer true. Remove declaration of futex_supports_exact_relative_timeouts. * sysdeps/unix/sysv/linux/futex-internal.h: Remove implementation of futex_supports_exact_relative_timeouts. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-07-12nptl: Add POSIX-proposed pthread_mutex_clocklockMike Crowe1-5/+4
Add POSIX-proposed pthread_mutex_clocklock function that works like pthread_mutex_timedlock but takes a clockid parameter to measure the abstime parameter against. * sysdeps/nptl/pthread.h: Add pthread_mutex_clocklock. * nptl/DESIGN-systemtap-probes.txt: Likewise. * nptl/pthread_mutex_timedlock.c (__pthread_mutex_clocklock_common): Rename from __pthread_mutex_timedlock and add clockid parameter. Pass this parameter to lll_clocklock and lll_clocklock_elision in place of CLOCK_REALTIME. (__pthread_mutex_clocklock): New function to add LIBC_PROBE and validate clockid parameter before calling __pthread_mutex_clocklock_common. (__pthread_mutex_timedlock): New implementation to add LIBC_PROBE and calls __pthread_mutex_clocklock_common passing CLOCK_REALTIME as the clockid. * nptl/Makefile: Add tst-mutex11.c. * nptl/tst-abstime.c (th): Add tests for pthread_mutex_clocklock. * nptl/tst-mutex11.c: New tests for passing invalid and unsupported clockid parameters to pthread_mutex_clocklock. * nptl/tst-mutex5.c (do_test_clock): Rename from do_test and take clockid parameter to indicate which clock to be used. Call pthread_mutex_timedlock or pthread_mutex_clocklock as appropriate. (do_test): Call do_test_clock to separately test pthread_mutex_timedlock, pthread_mutex_clocklock(CLOCK_REALTIME) and pthread_mutex_clocklock(CLOCK_MONOTONIC). * nptl/tst-mutex9.c: Likewise. * nptl/Versions (GLIBC_2.30): Add pthread_mutex_clocklock. * sysdeps/unix/sysv/linux/aarch64/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/alpha/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/arm/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/csky/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/hppa/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/i386/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/ia64/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/m68k/coldfire/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/m68k/m680x0/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/microblaze/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/mips/mips32/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/mips/mips64/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/nios2/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/riscv/rv64/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/s390/s390-32/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/s390/s390-64/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/sh/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/sparc/sparc32/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/sparc/sparc64/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/x86_64/64/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/x86_64/x32/libpthread.abilist (GLIBC_2.30): Likewise. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-07-12nptl: Add POSIX-proposed pthread_cond_clockwaitMike Crowe1-6/+38
Add: int pthread_cond_clockwait (pthread_cond_t *cond, pthread_mutex_t *mutex, clockid_t clockid, const struct timespec *abstime) which behaves just like pthread_cond_timedwait except it always measures abstime against the supplied clockid. Currently supports CLOCK_REALTIME and CLOCK_MONOTONIC and returns EINVAL if any other clock is specified. Includes feedback from many others. This function was originally proposed[1] as pthread_cond_timedwaitonclock_np, but The Austin Group preferred the new name. * nptl/Makefile: Add tst-cond26 and tst-cond27 * nptl/Versions (GLIBC_2.30): Add pthread_cond_clockwait * sysdeps/nptl/pthread.h: Likewise * nptl/forward.c: Add __pthread_cond_clockwait * nptl/forward.c: Likewise * nptl/pthreadP.h: Likewise * sysdeps/nptl/pthread-functions.h: Likewise * nptl/pthread_cond_wait.c (__pthread_cond_wait_common): Add clockid parameter and comment describing why we don't need to check its value. Use that value when calling futex_abstimed_wait_cancelable rather than reading the clock from the flags. (__pthread_cond_wait): Pass unused clockid parameter. (__pthread_cond_timedwait): Read clock from flags and pass it to __pthread_cond_wait_common. (__pthread_cond_clockwait): Add new function with weak alias from pthread_cond_clockwait. * sysdeps/mach/hurd/i386/libpthread.abilist (GLIBC_2.30): * Likewise. * sysdeps/unix/sysv/linux/aarch64/libpthread.abilist * (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/alpha/libpthread.abilist (GLIBC_2.30): * Likewise. * sysdeps/unix/sysv/linux/arm/libpthread.abilist (GLIBC_2.30): * Likewise. * sysdeps/unix/sysv/linux/csky/libpthread.abilist (GLIBC_2.30): * Likewise. * sysdeps/unix/sysv/linux/hppa/libpthread.abilist (GLIBC_2.30): * Likewise. * sysdeps/unix/sysv/linux/i386/libpthread.abilist (GLIBC_2.30): * Likewise. * sysdeps/unix/sysv/linux/ia64/libpthread.abilist (GLIBC_2.30): * Likewise. * sysdeps/unix/sysv/linux/m68k/coldfire/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/m68k/m680x0/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/microblaze/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/mips/mips32/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/mips/mips64/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/nios2/libpthread.abilist (GLIBC_2.30): * Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/riscv/rv64/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/s390/s390-32/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/s390/s390-64/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/sh/libpthread.abilist (GLIBC_2.30): * Likewise. * sysdeps/unix/sysv/linux/sparc/sparc32/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/sparc/sparc64/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/x86_64/64/libpthread.abilist (GLIBC_2.30): Likewise. * sysdeps/unix/sysv/linux/x86_64/x32/libpthread.abilist (GLIBC_2.30): Likewise. * nptl/tst-cond11.c (run_test): Support testing pthread_cond_clockwait too by using a special magic CLOCK_USE_ATTR_CLOCK value to determine whether to call pthread_cond_timedwait or pthread_cond_clockwait. (do_test): Pass CLOCK_USE_ATTR_CLOCK for existing tests, and add new tests using all combinations of CLOCK_MONOTONIC and CLOCK_REALTIME. * ntpl/tst-cond26.c: New test for passing unsupported and * invalid clocks to pthread_cond_clockwait. * nptl/tst-cond27.c: Add test similar to tst-cond5.c, but using struct timespec and pthread_cond_clockwait. * manual/threads.texi: Document pthread_cond_clockwait. The * comment was provided by Carlos O'Donell. [1] https://sourceware.org/ml/libc-alpha/2015-07/msg00193.html Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-07-12nptl: Add clockid parameter to futex timed wait callsMike Crowe1-26/+6
In preparation for adding POSIX clockwait variants of timedwait functions, add a clockid_t parameter to futex_abstimed_wait functions and pass CLOCK_REALTIME from all callers for the time being. Replace lll_futex_timed_wait_bitset with lll_futex_clock_wait_bitset which takes a clockid_t parameter rather than the magic clockbit. * sysdeps/nptl/lowlevellock-futex.h, sysdeps/unix/sysv/linux/lowlevellock-futex.h: Replace lll_futex_timed_wait_bitset with lll_futex_clock_wait_bitset that takes a clockid rather than a special clockbit. * sysdeps/nptl/lowlevellock-futex.h: Add lll_futex_supported_clockid so that client functions can check whether their clockid parameter is valid even if they don't ultimately end up calling lll_futex_clock_wait_bitset. * sysdeps/nptl/futex-internal.h, sysdeps/unix/sysv/linux/futex-internal.h (futex_abstimed_wait, futex_abstimed_wait_cancelable): Add clockid_t parameter to indicate which clock the absolute time passed should be measured against. Pass that clockid onto lll_futex_clock_wait_bitset. Add invalid clock as reason for returning -EINVAL. * sysdeps/nptl/futex-internal.h, sysdeps/unix/sysv/linux/futex-internal.h: Introduce futex_abstimed_supported_clockid so that client functions can check whether their clockid parameter is valid even if they don't ultimately end up calling futex_abstimed_wait. * nptl/pthread_cond_wait.c (__pthread_cond_wait_common): Remove code to calculate relative timeout for __PTHREAD_COND_CLOCK_MONOTONIC_MASK and just pass CLOCK_MONOTONIC or CLOCK_REALTIME as required to futex_abstimed_wait_cancelable. * nptl/pthread_rwlock_common (__pthread_rwlock_rdlock_full) (__pthread_wrlock_full), nptl/sem_waitcommon (do_futex_wait): Pass additional CLOCK_REALTIME to futex_abstimed_wait_cancelable. * nptl/pthread_mutex_timedlock.c (__pthread_mutex_timedlock): Switch to lll_futex_clock_wait_bitset and pass CLOCK_REALTIME Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers1-1/+1
* All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
2018-08-31[BZ #20271] Add newlines in __libc_fatal calls.Paul Pluzhnikov1-1/+1
2018-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers1-1/+1
* All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
2017-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers1-1/+1
2016-12-31New condvar implementation that provides stronger ordering guarantees.Torvald Riegel1-159/+595
This is a new implementation for condition variables, required after http://austingroupbugs.net/view.php?id=609 to fix bug 13165. In essence, we need to be stricter in which waiters a signal or broadcast is required to wake up; this couldn't be solved using the old algorithm. ISO C++ made a similar clarification, so this also fixes a bug in current libstdc++, for example. We can't use the old algorithm anymore because futexes do not guarantee to wake in FIFO order. Thus, when we wake, we can't simply let any waiter grab a signal, but we need to ensure that one of the waiters happening before the signal is woken up. This is something the previous algorithm violated (see bug 13165). There's another issue specific to condvars: ABA issues on the underlying futexes. Unlike mutexes that have just three states, or semaphores that have no tokens or a limited number of them, the state of a condvar is the *order* of the waiters. A waiter on a semaphore can grab a token whenever one is available; a condvar waiter must only consume a signal if it is eligible to do so as determined by the relative order of the waiter and the signal. Therefore, this new algorithm maintains two groups of waiters: Those eligible to consume signals (G1), and those that have to wait until previous waiters have consumed signals (G2). Once G1 is empty, G2 becomes the new G1. 64b counters are used to avoid ABA issues. This condvar doesn't yet use a requeue optimization (ie, on a broadcast, waking just one thread and requeueing all others on the futex of the mutex supplied by the program). I don't think doing the requeue is necessarily the right approach (but I haven't done real measurements yet): * If a program expects to wake many threads at the same time and make that scalable, a condvar isn't great anyway because of how it requires waiters to operate mutually exclusive (due to the mutex usage). Thus, a thundering herd problem is a scalability problem with or without the optimization. Using something like a semaphore might be more appropriate in such a case. * The scalability problem is actually at the mutex side; the condvar could help (and it tries to with the requeue optimization), but it should be the mutex who decides how that is done, and whether it is done at all. * Forcing all but one waiter into the kernel-side wait queue of the mutex prevents/avoids the use of lock elision on the mutex. Thus, it prevents the only cure against the underlying scalability problem inherent to condvars. * If condvars use short critical sections (ie, hold the mutex just to check a binary flag or such), which they should do ideally, then forcing all those waiter to proceed serially with kernel-based hand-off (ie, futex ops in the mutex' contended state, via the futex wait queues) will be less efficient than just letting a scalable mutex implementation take care of it. Our current mutex impl doesn't employ spinning at all, but if critical sections are short, spinning can be much better. * Doing the requeue stuff requires all waiters to always drive the mutex into the contended state. This leads to each waiter having to call futex_wake after lock release, even if this wouldn't be necessary. [BZ #13165] * nptl/pthread_cond_broadcast.c (__pthread_cond_broadcast): Rewrite to use new algorithm. * nptl/pthread_cond_destroy.c (__pthread_cond_destroy): Likewise. * nptl/pthread_cond_init.c (__pthread_cond_init): Likewise. * nptl/pthread_cond_signal.c (__pthread_cond_signal): Likewise. * nptl/pthread_cond_wait.c (__pthread_cond_wait): Likewise. (__pthread_cond_timedwait): Move here from pthread_cond_timedwait.c. (__condvar_confirm_wakeup, __condvar_cancel_waiting, __condvar_cleanup_waiting, __condvar_dec_grefs, __pthread_cond_wait_common): New. (__condvar_cleanup): Remove. * npt/pthread_condattr_getclock.c (pthread_condattr_getclock): Adapt. * npt/pthread_condattr_setclock.c (pthread_condattr_setclock): Likewise. * npt/pthread_condattr_getpshared.c (pthread_condattr_getpshared): Likewise. * npt/pthread_condattr_init.c (pthread_condattr_init): Likewise. * nptl/tst-cond1.c: Add comment. * nptl/tst-cond20.c (do_test): Adapt. * nptl/tst-cond22.c (do_test): Likewise. * sysdeps/aarch64/nptl/bits/pthreadtypes.h (pthread_cond_t): Adapt structure. * sysdeps/arm/nptl/bits/pthreadtypes.h (pthread_cond_t): Likewise. * sysdeps/ia64/nptl/bits/pthreadtypes.h (pthread_cond_t): Likewise. * sysdeps/m68k/nptl/bits/pthreadtypes.h (pthread_cond_t): Likewise. * sysdeps/microblaze/nptl/bits/pthreadtypes.h (pthread_cond_t): Likewise. * sysdeps/mips/nptl/bits/pthreadtypes.h (pthread_cond_t): Likewise. * sysdeps/nios2/nptl/bits/pthreadtypes.h (pthread_cond_t): Likewise. * sysdeps/s390/nptl/bits/pthreadtypes.h (pthread_cond_t): Likewise. * sysdeps/sh/nptl/bits/pthreadtypes.h (pthread_cond_t): Likewise. * sysdeps/tile/nptl/bits/pthreadtypes.h (pthread_cond_t): Likewise. * sysdeps/unix/sysv/linux/alpha/bits/pthreadtypes.h (pthread_cond_t): Likewise. * sysdeps/unix/sysv/linux/powerpc/bits/pthreadtypes.h (pthread_cond_t): Likewise. * sysdeps/x86/bits/pthreadtypes.h (pthread_cond_t): Likewise. * sysdeps/nptl/internaltypes.h (COND_NWAITERS_SHIFT): Remove. (COND_CLOCK_BITS): Adapt. * sysdeps/nptl/pthread.h (PTHREAD_COND_INITIALIZER): Adapt. * nptl/pthreadP.h (__PTHREAD_COND_CLOCK_MONOTONIC_MASK, __PTHREAD_COND_SHARED_MASK): New. * nptl/nptl-printers.py (CLOCK_IDS): Remove. (ConditionVariablePrinter, ConditionVariableAttributesPrinter): Adapt. * nptl/nptl_lock_constants.pysym: Adapt. * nptl/test-cond-printers.py: Adapt. * sysdeps/unix/sysv/linux/hppa/internaltypes.h (cond_compat_clear, cond_compat_check_and_clear): Adapt. * sysdeps/unix/sysv/linux/hppa/pthread_cond_timedwait.c: Remove file ... * sysdeps/unix/sysv/linux/hppa/pthread_cond_wait.c (__pthread_cond_timedwait): ... and move here. * nptl/DESIGN-condvar.txt: Remove file. * nptl/lowlevelcond.sym: Likewise. * nptl/pthread_cond_timedwait.c: Likewise. * sysdeps/unix/sysv/linux/i386/i486/pthread_cond_broadcast.S: Likewise. * sysdeps/unix/sysv/linux/i386/i486/pthread_cond_signal.S: Likewise. * sysdeps/unix/sysv/linux/i386/i486/pthread_cond_timedwait.S: Likewise. * sysdeps/unix/sysv/linux/i386/i486/pthread_cond_wait.S: Likewise. * sysdeps/unix/sysv/linux/i386/i586/pthread_cond_broadcast.S: Likewise. * sysdeps/unix/sysv/linux/i386/i586/pthread_cond_signal.S: Likewise. * sysdeps/unix/sysv/linux/i386/i586/pthread_cond_timedwait.S: Likewise. * sysdeps/unix/sysv/linux/i386/i586/pthread_cond_wait.S: Likewise. * sysdeps/unix/sysv/linux/i386/i686/pthread_cond_broadcast.S: Likewise. * sysdeps/unix/sysv/linux/i386/i686/pthread_cond_signal.S: Likewise. * sysdeps/unix/sysv/linux/i386/i686/pthread_cond_timedwait.S: Likewise. * sysdeps/unix/sysv/linux/i386/i686/pthread_cond_wait.S: Likewise. * sysdeps/unix/sysv/linux/x86_64/pthread_cond_broadcast.S: Likewise. * sysdeps/unix/sysv/linux/x86_64/pthread_cond_signal.S: Likewise. * sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S: Likewise. * sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S: Likewise.
2016-01-0