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* linux: Use __libc_single_threaded on forkAdhemerval Zanella2021-03-121-1/+2
| | | | Checked on x86_64-linux-gnu.
* Implement <unwind-link.h> for dynamically loading the libgcc_s unwinderFlorian Weimer2021-03-011-0/+3
| | | | | | | | | | This will be used to consolidate the libgcc_s access for backtrace and pthread_cancel. Unlike the existing backtrace implementations, it provides some hardening based on pointer mangling. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* Update copyright dates with scripts/update-copyrightsPaul Eggert2021-01-021-1/+1
| | | | | | | | | | | | | | | | I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 6694 files FOO. I then removed trailing white space from benchtests/bench-pthread-locks.c and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this diagnostic from Savannah: remote: *** pre-commit check failed ... remote: *** error: lines with trailing whitespace found remote: error: hook declined to update refs/heads/master
* nss: Implement <nss_database.h>Florian Weimer2020-12-041-0/+9
| | | | | | | | | | | This code manages the mappings of the available databases in NSS (i.e. passwd, hosts, netgroup, etc) with the actions that should be taken to do a query on those databases. This is the main API between query functions scattered throughout glibc and the underlying code (actions, modules, etc). Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
* Linux: set_robust_list syscall number is always availableFlorian Weimer2020-03-031-6/+4
| | | | | | | Due to the built-in tables, __NR_set_robust_list is always defined (although it may not be available at run time). Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* Update copyright dates with scripts/update-copyrights.Joseph Myers2020-01-011-1/+1
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* Prefer https to http for gnu.org and fsf.org URLsPaul Eggert2019-09-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^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
* nptl: Remove pthread_clock_gettime pthread_clock_settimeAdhemerval Zanella2019-03-221-8/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch removes CLOCK_THREAD_CPUTIME_ID and CLOCK_PROCESS_CPUTIME_ID support from clock_gettime and clock_settime generic implementation. For Linux, kernel already provides supports through the syscall and Hurd HTL lacks __pthread_clock_gettime and __pthread_clock_settime internal implementation. As described in clock_gettime man-page [1] on 'Historical note for SMP system', implementing CLOCK_{THREAD,PROCESS}_CPUTIME_ID with timer registers is error-prone and susceptible to timing and accurary issues that the libc can not deal without kernel support. This allows removes unused code which, however, still incur in some runtime overhead in thread creation (the struct pthread cpuclock_offset initialization). If hurd eventually wants to support them it should either either implement as a kernel facility (or something related due its architecture) or in system specific implementation. Checked on aarch64-linux-gnu, x86_64-linux-gnu, and i686-linux-gnu. I also checked on a i686-gnu build. * nptl/Makefile (libpthread-routines): Remove pthread_clock_gettime and pthread_clock_settime. * nptl/pthreadP.h (__find_thread_by_id): Remove prototype. * elf/dl-support.c [!HP_TIMING_NOAVAIL] (_dl_cpuclock_offset): Remove. (_dl_non_dynamic_init): Remove _dl_cpuclock_offset setting. * elf/rtld.c (_dl_start_final): Likewise. * nptl/allocatestack.c (__find_thread_by_id): Remove function. * sysdeps/generic/ldsodefs.h [!HP_TIMING_NOAVAIL] (_dl_cpuclock_offset): Remove. * sysdeps/mach/hurd/dl-sysdep.c [!HP_TIMING_NOAVAIL] (_dl_cpuclock_offset): Remove. * nptl/descr.h (struct pthread): Rename cpuclock_offset to cpuclock_offset_ununsed. * nptl/nptl-init.c (__pthread_initialize_minimal_internal): Remove cpuclock_offset set. * nptl/pthread_create.c (START_THREAD_DEFN): Likewise. * sysdeps/nptl/fork.c (__libc_fork): Likewise. * nptl/pthread_clock_gettime.c: Remove file. * nptl/pthread_clock_settime.c: Likewise. * sysdeps/unix/clock_gettime.c (hp_timing_gettime): Remove function. [HP_TIMING_AVAIL] (realtime_gettime): Remove CLOCK_THREAD_CPUTIME_ID and CLOCK_PROCESS_CPUTIME_ID support. * sysdeps/unix/clock_settime.c (hp_timing_gettime): Likewise. [HP_TIMING_AVAIL] (realtime_gettime): Likewise. * sysdeps/posix/clock_getres.c (hp_timing_getres): Likewise. [HP_TIMING_AVAIL] (__clock_getres): Likewise. * sysdeps/unix/clock_nanosleep.c (CPUCLOCK_P, INVALID_CLOCK_P): Likewise. (__clock_nanosleep): Remove CPUCLOCK_P and INVALID_CLOCK_P usage. [1] http://man7.org/linux/man-pages/man2/clock_gettime.2.html
* nptl: Avoid fork handler lock for async-signal-safe fork [BZ #24161]Florian Weimer2019-02-081-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 27761a1042daf01987e7d79636d0c41511c6df3c ("Refactor atfork handlers") introduced a lock, atfork_lock, around fork handler list accesses. It turns out that this lock occasionally results in self-deadlocks in malloc/tst-mallocfork2: (gdb) bt #0 __lll_lock_wait_private () at ../sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:63 #1 0x00007f160c6f927a in __run_fork_handlers (who=(unknown: 209394016), who@entry=atfork_run_prepare) at register-atfork.c:116 #2 0x00007f160c6b7897 in __libc_fork () at ../sysdeps/nptl/fork.c:58 #3 0x00000000004027d6 in sigusr1_handler (signo=<optimized out>) at tst-mallocfork2.c:80 #4 sigusr1_handler (signo=<optimized out>) at tst-mallocfork2.c:64 #5 <signal handler called> #6 0x00007f160c6f92e4 in __run_fork_handlers (who=who@entry=atfork_run_parent) at register-atfork.c:136 #7 0x00007f160c6b79a2 in __libc_fork () at ../sysdeps/nptl/fork.c:152 #8 0x0000000000402567 in do_test () at tst-mallocfork2.c:156 #9 0x0000000000402dd2 in support_test_main (argc=1, argv=0x7ffc81ef1ab0, config=config@entry=0x7ffc81ef1970) at support_test_main.c:350 #10 0x0000000000402362 in main (argc=<optimized out>, argv=<optimized out>) at ../support/test-driver.c:168 If no locking happens in the single-threaded case (where fork is expected to be async-signal-safe), this deadlock is avoided. (pthread_atfork is not required to be async-signal-safe, so a fork call from a signal handler interrupting pthread_atfork is not a problem.)
* Update copyright dates with scripts/update-copyrights.Joseph Myers2019-01-011-1/+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.
* Refactor Linux ARCH_FORK implementationAdhemerval Zanella2018-03-071-7/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch refactors the ARCH_FORK macro and the required architecture specific header to simplify the required architecture definitions to provide the fork syscall semantic and proper document current Linux clone ABI variant. Instead of require the reimplementation of arch-fork.h header, this patch changes the ARCH_FORK to an inline function with clone ABI defined by kernel-features.h define. The generic kernel ABI meant for newer ports is used as default and redefine if the architecture requires. Checked on x86_64-linux-gnu and i686-linux-gnu. Also with a build for all the afected ABIs. * sysdeps/nptl/fork.c (ARCH_FORK): Replace by auch_fork. * sysdeps/unix/sysv/linux/alpha/arch-fork.h: Remove file. * sysdeps/unix/sysv/linux/riscv/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/aarch64/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/arm/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/hppa/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/i386/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/ia64/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/m68k/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/microblaze/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/mips/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/nios2/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/powerpc/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/s390/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/sh/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/sparc/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/tile/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/x86_64/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/arch-fork.h (arch_fork): New function. * sysdeps/unix/sysv/linux/aarch64/kernel-features.h: New file. * sysdeps/unix/sysv/linux/riscv/kernel-features.h: Likewise. * sysdeps/unix/sysv/linux/arm/kernel-features.h (__ASSUME_CLONE_BACKWARDS): Define. * sysdeps/unix/sysv/linux/createthread.c (ARCH_CLONE): Define to __clone2 if __NR_clone2 is defined. * sysdeps/unix/sysv/linux/hppa/kernel-features.h (__ASSUME_CLONE_BACKWARDS): Likewise. * sysdeps/unix/sysv/linux/i386/kernel-features.h (__ASSUME_CLONE_BACKWARDS): Likewise. * sysdeps/unix/sysv/linux/ia64/kernel-features.h (__ASSUME_CLONE2): Likewise. * sysdeps/unix/sysv/linux/microblaze/kernel-features.h (__ASSUME_CLONE_BACKWARDS3): Likewise. * sysdeps/unix/sysv/linux/kernel-features.h: Document possible clone variants and the define architecture can use. (__ASSUME_CLONE_DEFAULT): Define as default. * sysdeps/unix/sysv/linux/mips/kernel-features.h (__ASSUME_CLONE_BACKWARDS): Likewise. * sysdeps/unix/sysv/linux/powerpc/kernel-features.h (__ASSUME_CLONE_BACKWARDS): Likewise. * sysdeps/unix/sysv/linux/s390/kernel-features.h (__ASSUME_CLONE_BACKWARDS2): Likewise.
* Refactor atfork handlersAdhemerval Zanella2018-02-221-93/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Current implementation (sysdeps/nptl/fork.c) replicates the atfork handlers list backward to invoke the child handlers after fork/clone syscall. The internal atfork handlers is implemented as a single-linked list so a lock-free algorithm can be used, trading fork mulithread call performance for some code complexity and dynamic stack allocation (since the backwards list should not fail). This patch refactor it to use a dynarary instead of a linked list. It simplifies the external variables need to be exported and also the internal atfork handler member definition. The downside is a serialization of fork call in multithread, since to operate on the dynarray the internal lock should be used. However as noted by Florian, it already acquires external locks for malloc and libio so it is already hitting some lock contention. Besides, posix_spawn should be faster and more scalable to run external programs in multithread environments. Checked on x86_64-linux-gnu. * nptl/Makefile (routines): Remove unregister-atfork. * nptl/register-atfork.c (fork_handler_pool): Remove variable. (fork_handler_alloc): Remove function. (fork_handlers, fork_handler_init): New variables. (__fork_lock): Rename to atfork_lock. (__register_atfork, __unregister_atfork, libc_freeres_fn): Rewrite to use a dynamic array to add/remove atfork handlers. * sysdeps/nptl/fork.c (__libc_fork): Likewise. * sysdeps/nptl/fork.h (__fork_lock, __fork_handlers, __linkin_atfork): Remove declaration. (fork_handler): Remove next, refcntr, and need_signal member. (__run_fork_handler_type): New enum. (__run_fork_handlers): New prototype. * sysdeps/nptl/libc-lockP.h (__libc_atfork): Remove declaration.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2018-01-011-1/+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.
* nptl: Define __PTHREAD_MUTEX_{NUSERS_AFTER_KIND,USE_UNION}Adhemerval Zanella2017-11-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds two new internal defines to set the internal pthread_mutex_t layout required by the supported ABIS: 1. __PTHREAD_MUTEX_NUSERS_AFTER_KIND which control whether to define __nusers fields before or after __kind. The preferred value for is 0 for new ports and it sets __nusers before __kind. 2. __PTHREAD_MUTEX_USE_UNION which control whether internal __spins and __list members will be place inside an union for linuxthreads compatibility. The preferred value is 0 for ports and it sets to not use an union to define both fields. It fixes the wrong offsets value for __kind value on x86_64-linux-gnu-x32. Checked with a make check run-built-tests=no on all afected ABIs. [BZ #22298] * nptl/allocatestack.c (allocate_stack): Check if __PTHREAD_MUTEX_HAVE_PREV is non-zero, instead if __PTHREAD_MUTEX_HAVE_PREV is defined. * nptl/descr.h (pthread): Likewise. * nptl/nptl-init.c (__pthread_initialize_minimal_internal): Likewise. * nptl/pthread_create.c (START_THREAD_DEFN): Likewise. * sysdeps/nptl/fork.c (__libc_fork): Likewise. * sysdeps/nptl/pthread.h (PTHREAD_MUTEX_INITIALIZER): Likewise. * sysdeps/nptl/bits/thread-shared-types.h (__PTHREAD_MUTEX_NUSERS_AFTER_KIND, __PTHREAD_MUTEX_USE_UNION): New defines. (__pthread_internal_list): Check __PTHREAD_MUTEX_USE_UNION instead of __WORDSIZE for internal layout. (__pthread_mutex_s): Check __PTHREAD_MUTEX_NUSERS_AFTER_KIND instead of __WORDSIZE for internal __nusers layout and __PTHREAD_MUTEX_USE_UNION instead of __WORDSIZE whether to use an union for __spins and __list fields. (__PTHREAD_MUTEX_HAVE_PREV): Define also for __PTHREAD_MUTEX_USE_UNION case. * sysdeps/aarch64/nptl/bits/pthreadtypes-arch.h (__PTHREAD_MUTEX_NUSERS_AFTER_KIND, __PTHREAD_MUTEX_USE_UNION): New defines. * sysdeps/alpha/nptl/bits/pthreadtypes-arch.h (__PTHREAD_MUTEX_NUSERS_AFTER_KIND, __PTHREAD_MUTEX_USE_UNION): Likewise. * sysdeps/arm/nptl/bits/pthreadtypes-arch.h (__PTHREAD_MUTEX_NUSERS_AFTER_KIND, __PTHREAD_MUTEX_USE_UNION): Likewise. * sysdeps/hppa/nptl/bits/pthreadtypes-arch.h (__PTHREAD_MUTEX_NUSERS_AFTER_KIND, __PTHREAD_MUTEX_USE_UNION): Likewise. * sysdeps/ia64/nptl/bits/pthreadtypes-arch.h (__PTHREAD_MUTEX_NUSERS_AFTER_KIND, __PTHREAD_MUTEX_USE_UNION): Likewise. * sysdeps/m68k/nptl/bits/pthreadtypes-arch.h (__PTHREAD_MUTEX_NUSERS_AFTER_KIND, __PTHREAD_MUTEX_USE_UNION): Likewise. * sysdeps/microblaze/nptl/bits/pthreadtypes-arch.h (__PTHREAD_MUTEX_NUSERS_AFTER_KIND, __PTHREAD_MUTEX_USE_UNION): Likewise. * sysdeps/mips/nptl/bits/pthreadtypes-arch.h (__PTHREAD_MUTEX_NUSERS_AFTER_KIND, __PTHREAD_MUTEX_USE_UNION): Likewise. * sysdeps/nios2/nptl/bits/pthreadtypes-arch.h (__PTHREAD_MUTEX_NUSERS_AFTER_KIND, __PTHREAD_MUTEX_USE_UNION): Likewise. * sysdeps/powerpc/nptl/bits/pthreadtypes-arch.h (__PTHREAD_MUTEX_NUSERS_AFTER_KIND, __PTHREAD_MUTEX_USE_UNION): Likewise. * sysdeps/s390/nptl/bits/pthreadtypes-arch.h (__PTHREAD_MUTEX_NUSERS_AFTER_KIND, __PTHREAD_MUTEX_USE_UNION): Likewise. * sysdeps/sh/nptl/bits/pthreadtypes-arch.h (__PTHREAD_MUTEX_NUSERS_AFTER_KIND, __PTHREAD_MUTEX_USE_UNION): Likewise. * sysdeps/sparc/nptl/bits/pthreadtypes-arch.h (__PTHREAD_MUTEX_NUSERS_AFTER_KIND, __PTHREAD_MUTEX_USE_UNION): Likewise. * sysdeps/tile/nptl/bits/pthreadtypes-arch.h (__PTHREAD_MUTEX_NUSERS_AFTER_KIND, __PTHREAD_MUTEX_USE_UNION): Likewise. * sysdeps/x86/nptl/bits/pthreadtypes-arch.h (__PTHREAD_MUTEX_NUSERS_AFTER_KIND, __PTHREAD_MUTEX_USE_UNION): Likewise. Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* fork: Remove bogus parent PID assertions [BZ #21386]Florian Weimer2017-05-121-8/+0
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* Clear list of acquired robust mutexes in the child process after forking.Torvald Riegel2017-01-131-6/+14
| | | | | | | | | | | | | | Robust mutexes acquired at the time of a call to fork() do not remain acquired by the forked child process. We have to clear the list of acquired robust mutexes before registering this list with the kernel; otherwise, if some of the robust mutexes are process-shared, the parent process can alter the child's robust mutex list, which can lead to deadlocks or even modification of memory that may not be occupied by a mutex anymore. [BZ #19402] * sysdeps/nptl/fork.c (__libc_fork): Clear list of acquired robust mutexes.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2017-01-011-1/+1
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* Remove cached PID/TID in cloneAdhemerval Zanella2016-11-241-12/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch remove the PID cache and usage in current GLIBC code. Current usage is mainly used a performance optimization to avoid the syscall, however it adds some issues: - The exposed clone syscall will try to set pid/tid to make the new thread somewhat compatible with current GLIBC assumptions. This cause a set of issue with new workloads and usecases (such as BZ#17214 and [1]) as well for new internal usage of clone to optimize other algorithms (such as clone plus CLONE_VM for posix_spawn, BZ#19957). - The caching complexity also added some bugs in the past [2] [3] and requires more effort of each port to handle such requirements (for both clone and vfork implementation). - Caching performance gain in mainly on getpid and some specific code paths. The getpid performance leverage is questionable [4], either by the idea of getpid being a hotspot as for the getpid implementation itself (if it is indeed a justifiable hotspot a vDSO symbol could let to a much more simpler solution). Other usage is mainly for non usual code paths, such as pthread cancellation signal and handling. For thread creation (on stack allocation) the code simplification in fact adds some performance gain due the no need of transverse the stack cache and invalidate each element pid. Other thread usages will require a direct getpid syscall, such as cancellation/setxid signal, thread cancellation, thread fail path (at create_thread), and thread signal (pthread_kill and pthread_sigqueue). However these are hardly usual hotspots and I think adding a syscall is justifiable. It also simplifies both the clone and vfork arch-specific implementation. And by review each fork implementation there are some discrepancies that this patch also solves: - microblaze clone/vfork does not set/reset the pid/tid field - hppa uses the default vfork implementation that fallback to fork. Since vfork is deprecated I do not think we should bother with it. The patch also removes the TID caching in clone. My understanding for such semantic is try provide some pthread usage after a user program issue clone directly (as done by thread creation with CLONE_PARENT_SETTID and pthread tid member). However, as stated before in multiple discussions threads, GLIBC provides clone syscalls without further supporting all this semantics. I ran a full make check on x86_64, x32, i686, armhf, aarch64, and powerpc64le. For sparc32, sparc64, and mips I ran the basic fork and vfork tests from posix/ folder (on a qemu system). So it would require further testing on alpha, hppa, ia64, m68k, nios2, s390, sh, and tile (I excluded microblaze because it is already implementing the patch semantic regarding clone/vfork). [1] https://codereview.chromium.org/800183004/ [2] https://sourceware.org/ml/libc-alpha/2006-07/msg00123.html [3] https://sourceware.org/bugzilla/show_bug.cgi?id=15368 [4] http://yarchive.net/comp/linux/getpid_caching.html * sysdeps/nptl/fork.c (__libc_fork): Remove pid cache setting. * nptl/allocatestack.c (allocate_stack): Likewise. (__reclaim_stacks): Likewise. (setxid_signal_thread): Obtain pid through syscall. * nptl/nptl-init.c (sigcancel_handler): Likewise. (sighandle_setxid): Likewise. * nptl/pthread_cancel.c (pthread_cancel): Likewise. * sysdeps/unix/sysv/linux/pthread_kill.c (__pthread_kill): Likewise. * sysdeps/unix/sysv/linux/pthread_sigqueue.c (pthread_sigqueue): Likewise. * sysdeps/unix/sysv/linux/createthread.c (create_thread): Likewise. * sysdeps/unix/sysv/linux/getpid.c: Remove file. * nptl/descr.h (struct pthread): Change comment about pid value. * nptl/pthread_getattr_np.c (pthread_getattr_np): Remove thread pid assert. * sysdeps/unix/sysv/linux/pthread-pids.h (__pthread_initialize_pids): Do not set pid value. * nptl_db/td_ta_thr_iter.c (iterate_thread_list): Remove thread pid cache check. * nptl_db/td_thr_validate.c (td_thr_validate): Likewise. * sysdeps/aarch64/nptl/tcb-offsets.sym: Remove pid offset. * sysdeps/alpha/nptl/tcb-offsets.sym: Likewise. * sysdeps/arm/nptl/tcb-offsets.sym: Likewise. * sysdeps/hppa/nptl/tcb-offsets.sym: Likewise. * sysdeps/i386/nptl/tcb-offsets.sym: Likewise. * sysdeps/ia64/nptl/tcb-offsets.sym: Likewise. * sysdeps/m68k/nptl/tcb-offsets.sym: Likewise. * sysdeps/microblaze/nptl/tcb-offsets.sym: Likewise. * sysdeps/mips/nptl/tcb-offsets.sym: Likewise. * sysdeps/nios2/nptl/tcb-offsets.sym: Likewise. * sysdeps/powerpc/nptl/tcb-offsets.sym: Likewise. * sysdeps/s390/nptl/tcb-offsets.sym: Likewise. * sysdeps/sh/nptl/tcb-offsets.sym: Likewise. * sysdeps/sparc/nptl/tcb-offsets.sym: Likewise. * sysdeps/tile/nptl/tcb-offsets.sym: Likewise. * sysdeps/x86_64/nptl/tcb-offsets.sym: Likewise. * sysdeps/unix/sysv/linux/aarch64/clone.S: Remove pid and tid caching. * sysdeps/unix/sysv/linux/alpha/clone.S: Likewise. * sysdeps/unix/sysv/linux/arm/clone.S: Likewise. * sysdeps/unix/sysv/linux/hppa/clone.S: Likewise. * sysdeps/unix/sysv/linux/i386/clone.S: Likewise. * sysdeps/unix/sysv/linux/ia64/clone2.S: Likewise. * sysdeps/unix/sysv/linux/mips/clone.S: Likewise. * sysdeps/unix/sysv/linux/nios2/clone.S: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/clone.S: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc64/clone.S: Likewise. * sysdeps/unix/sysv/linux/s390/s390-32/clone.S: Likewise. * sysdeps/unix/sysv/linux/s390/s390-64/clone.S: Likewise. * sysdeps/unix/sysv/linux/sh/clone.S: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc32/clone.S: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc64/clone.S: Likewise. * sysdeps/unix/sysv/linux/tile/clone.S: Likewise. * sysdeps/unix/sysv/linux/x86_64/clone.S: Likewise. * sysdeps/unix/sysv/linux/aarch64/vfork.S: Remove pid set and reset. * sysdeps/unix/sysv/linux/alpha/vfork.S: Likewise. * sysdeps/unix/sysv/linux/arm/vfork.S: Likewise. * sysdeps/unix/sysv/linux/i386/vfork.S: Likewise. * sysdeps/unix/sysv/linux/ia64/vfork.S: Likewise. * sysdeps/unix/sysv/linux/m68k/clone.S: Likewise. * sysdeps/unix/sysv/linux/m68k/vfork.S: Likewise. * sysdeps/unix/sysv/linux/mips/vfork.S: Likewise. * sysdeps/unix/sysv/linux/nios2/vfork.S: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/vfork.S: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc64/vfork.S: Likewise. * sysdeps/unix/sysv/linux/s390/s390-32/vfork.S: Likewise. * sysdeps/unix/sysv/linux/s390/s390-64/vfork.S: Likewise. * sysdeps/unix/sysv/linux/sh/vfork.S: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc32/vfork.S: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc64/vfork.S: Likewise. * sysdeps/unix/sysv/linux/tile/vfork.S: Likewise. * sysdeps/unix/sysv/linux/x86_64/vfork.S: Likewise. * sysdeps/unix/sysv/linux/tst-clone2.c (f): Remove direct pthread struct access. (clone_test): Remove function. (do_test): Rewrite to take in consideration pid is not cached anymore.
* malloc: Simplify static malloc interposition [BZ #20432]Florian Weimer2016-08-261-3/+3
| | | | | | | | Existing interposed mallocs do not define the glibc-internal fork callbacks (and they should not), so statically interposed mallocs lead to link failures because the strong reference from fork pulls in glibc's malloc, resulting in multiple definitions of malloc-related symbols.
* Increase fork signal safety for single-threaded processes [BZ #19703]Florian Weimer2016-05-121-15/+38
| | | | | | | | | This provides a band-aid and addresses the scenario where fork is called from a signal handler while the process is in the malloc subsystem (or has acquired the libio list lock). It does not address the general issue of async-signal-safety of fork; multi-threaded processes are not covered, and some glibc subsystems have fork handlers which are not async-signal-safe.
* malloc: Run fork handler as late as possible [BZ #19431]Florian Weimer2016-04-141-1/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | Previously, a thread M invoking fork would acquire locks in this order: (M1) malloc arena locks (in the registered fork handler) (M2) libio list lock A thread F invoking flush (NULL) would acquire locks in this order: (F1) libio list lock (F2) individual _IO_FILE locks A thread G running getdelim would use this order: (G1) _IO_FILE lock (G2) malloc arena lock After executing (M1), (F1), (G1), none of the threads can make progress. This commit changes the fork lock order to: (M'1) libio list lock (M'2) malloc arena locks It explicitly encodes the lock order in the implementations of fork, and does not rely on the registration order, thus avoiding the deadlock.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2016-01-041-1/+1
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* Rename bits/stdio-lock.h to stdio-lock.h (bug 14912).Joseph Myers2015-09-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | It was noted in <https://sourceware.org/ml/libc-alpha/2012-09/msg00305.html> that the bits/*.h naming scheme should only be used for installed headers. This patch renames bits/stdio-lock.h to plain stdio-lock.h to follow that convention. Tested for x86_64 (testsuite, and that installed stripped shared libraries are unchanged by the patch). [BZ #14912] * bits/stdio-lock.h: Move to ... * sysdeps/generic/stdio-lock.h: ...here. (_BITS_STDIO_LOCK_H): Rename macro to _STDIO_LOCK_H. * sysdeps/nptl/bits/stdio-lock.h: Move to ... * sysdeps/nptl/stdio-lock.h: ...here. (_BITS_STDIO_LOCK_H): Rename macro to _STDIO_LOCK_H. * include/libio.h: Include <stdio-lock.h> instead of <bits/stdio-lock.h>. * sysdeps/nptl/fork.c: Likewise. * sysdeps/pthread/flockfile.c: Likewise. * sysdeps/pthread/ftrylockfile.c: Likewise. * sysdeps/pthread/funlockfile.c: Likewise.
* Add and use new glibc-internal futex API.Torvald Riegel2015-07-101-1/+2
| | | | | | | | | | | | | | | | | | | | 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.
* Fix wake-up in sysdeps/nptl/fork.c.Torvald Riegel2015-01-131-1/+1
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* Update copyright dates with scripts/update-copyrights.Joseph Myers2015-01-021-1/+1
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* NPTL: Move fork state variables to initializer files.Roland McGrath2014-12-171-8/+0
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* Don't touch user-controlled stdio locks in forked child (bug 12847)Andreas Schwab2014-12-101-1/+2
| | | | | The stdio locks for streams with the _IO_USER_LOCK flag should not be touched by internal code.
* pthread_once: Clean up constants.Torvald Riegel2014-10-201-1/+2
| | | | [BZ #15215] This just gives a name to the integer constants being used.
* NPTL is no longer an add-on!Roland McGrath2014-07-071-1/+1
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* Get rid of nptl/sysdeps/ entirely!Roland McGrath2014-07-071-0/+238