aboutsummaryrefslogtreecommitdiff
path: root/nptl
AgeCommit message (Collapse)Author
2017-05-03Bug 20116: Clarify behaviour of PD->lock.Carlos O'Donell
Add comments to the concurrency notes to clarify the semaphore-like and mutex-like behaviours of PD->lock.
2017-05-01nptl: Using libsupport for tst-cancel4*Adhemerval Zanella
Checked on x86_64-linux-gnu. * nptl/tst-cancel4-common.c: Use libsupport. * nptl/tst-cancel4-common.h: Likewise. * nptl/tst-cancel4.c (tf_read): Likewise. (tf_readv): Likewise. (tf_write): Likewise. (tf_writev): Likewise. (tf_sleep): Likewise. (tf_usleep): Likewise. (tf_nanosleep): Likewise. (tf_select): Likewise. (tf_pselect): Likewise. (tf_poll): Likewise. (tf_ppoll): Likewise. (tf_wait): Likewise. (tf_waitpid): Likewise. (tf_waitid): Likewise. (tf_sigpause): Likewise. (tf_sigsuspend): Likewise. (tf_sigwait): Likewise. (tf_sigwaitinfo): Likewise. (tf_sigtimedwait): Likewise. (tf_pause): Likewise. (tf_accept): Likewise. (tf_send): Likewise. (tf_recv): Likewise. (tf_recvfrom): Likewise. (tf_recvmsg): Likewise. (tf_open): Likewise. (tf_close): Likewise. (tf_pread): Likewise. (tf_pwrite): Likewise. (tf_preadv): Likewise. (tf_pwritev): Likewise. (tf_fsync): Likewise. (tf_fdatasync): Likewise. (tf_msync): Likewise. (tf_sendto): Likewise. (tf_sendmsg): Likewise. (tf_creat): Likewise. (tf_connect): Likewise. (tf_tcdrain): Likewise. (tf_msgrcv): Likewise. (tf_msgsnd): Likewise. * nptl/tst-cancel4_1.c (tf_sendmmsg): Likewise. * nptl/tst-cancel4_2.c (tf_recvmmsg): Likewise.
2017-04-25Fix sys/socket.h namespace issues from sys/uio.h inclusion (bug 21426).Joseph Myers
sys/socket.h includes sys/uio.h to get the definition of the iovec structure. POSIX allows sys/socket.h to make all sys/uio.h symbols visible. However, all of sys/uio.h is XSI-shaded, so for non-XSI POSIX this results in conformtest failures (for sys/socket.h and other headers that include it): Namespace violation: "UIO_MAXIOV" Namespace violation: "readv" Namespace violation: "writev" Now, there is some ambiguity in POSIX about what namespace reservations apply in this case - see http://austingroupbugs.net/view.php?id=1127 - but glibc convention would still avoid declaring readv and writev, for example, for feature test macros that don't include them (if only headers from the relevant standard are included), even if such declarations are permitted, so there is a bug here according to glibc conventions. This patch moves the struct iovec definition to a new bits/types/struct_iovec.h header and includes that from sys/socket.h instead of including the whole of sys/uio.h. This fixes the namespace issue; however, three files in glibc that were relying on the implicit inclusion needed to be updated to include sys/uio.h explicitly. So there is a question of whether sys/socket.h should continue to include sys/uio.h under some conditions, such as __USE_XOPEN or __USE_MISC or __USE_XOPEN || __USE_MISC, for greater compatibility with code that (wrongly) expects this optional inclusion to be present there. (I think the three affected files in glibc should still have explicit sys/uio.h inclusions added in any case, however.) Tested for x86_64. [BZ #21426] * misc/bits/types/struct_iovec.h: New file. * misc/Makefile (headers): Add bits/types/struct_iovec.h. * include/bits/types/struct_iovec.h: New file. * bits/uio.h (struct iovec): Replace by inclusion of <bits/types/struct_iovec.h>. * sysdeps/unix/sysv/linux/bits/uio.h (struct iovec): Likewise. * socket/sys/socket.h: Include <bits/types/struct_iovec.h> instead of <sys/uio.h>. * nptl/tst-cancel4.c: Include <sys/uio.h> * posix/test-errno.c: Likewise. * support/resolv_test.c: Likewise. * conform/Makefile (test-xfail-POSIX2008/arpa/inet.h/conform): Remove. (test-xfail-POSIX2008/netdb.h/conform): Likewise. (test-xfail-POSIX2008/netinet/in.h/conform): Likewise. (test-xfail-POSIX2008/sys/socket.h/conform): Likewise.
2017-04-04Remove CALL_THREAD_FCT macroAdhemerval Zanella
This patch removes CALL_THREAD_FCT macro usage and its defition for x86. For 32 bits it usage is only for force 16 stack alignment, however stack is already explicit aligned in clone syscall. For 64 bits and x32 it just a function call and there is no need to code it with inline assembly. Checked on i686-linux-gnu, x86_64-linux-gnu, and x86_64-linux-gnu-x32. * nptl/pthread_create.c (START_THREAD_DEFN): Remove CALL_THREAD_FCT macro usage. * sysdeps/i386/nptl/tls.h (CALL_THREAD_FCT): Remove definition. * sysdeps/x86_64/nptl/tls.h (CALL_THREAD_FCT): Likewise. * sysdeps/x86_64/32/nptl/tls.h: Remove file.
2017-04-04Remove __ASSUME_REQUEUE_PIAdhemerval Zanella
The new cond var implementation (ed19993b5b0d) removed all the __ASSUME_{REQUEUE_PI,FUTEX_LOCK_PI} internal usage so there is no need to keep defining it. This patch removes all USE_REQUEUE_PI and __ASSUME_REQUEUE_PI. It is as follow up from BZ#18463. Checked with a build for x86_64-linux-gnu, arm-linux-gnueabhf, m68-linux-gnu, mips64-linux-gnu, and sparc64-linux-gnu. * nptl/pthreadP.h (USE_REQUEUE_PI): Remove ununsed macro. * sysdeps/unix/sysv/linux/arm/kernel-features.h (__ASSUME_REQUEUE_PI): Likewise. * sysdeps/unix/sysv/linux/kernel-features.h (__ASSUME_REQUEUE_PI): Likewise. * sysdeps/unix/sysv/linux/m68k/kernel-features.h (__ASSUME_REQUEUE_PI): Likewise. * sysdeps/unix/sysv/linux/mips/kernel-features.h (__ASSUME_REQUEUE_PI): Likewise. * sysdeps/unix/sysv/linux/sparc/kernel-features.h (__ASSUME_REQUEUE_PI): Likewise.
2017-03-01Narrowing the visibility of libc-internal.h even further.Zack Weinberg
posix/wordexp-test.c used libc-internal.h for PTR_ALIGN_DOWN; similar to what was done with libc-diag.h, I have split the definitions of cast_to_integer, ALIGN_UP, ALIGN_DOWN, PTR_ALIGN_UP, and PTR_ALIGN_DOWN to a new header, libc-pointer-arith.h. It then occurred to me that the remaining declarations in libc-internal.h are mostly to do with early initialization, and probably most of the files including it, even in the core code, don't need it anymore. Indeed, only 19 files actually need what remains of libc-internal.h. 23 others need libc-diag.h instead, and 12 need libc-pointer-arith.h instead. No file needs more than one of them, and 16 don't need any of them! So, with this patch, libc-internal.h stops including libc-diag.h as well as losing the pointer arithmetic macros, and all including files are adjusted. * include/libc-pointer-arith.h: New file. Define cast_to_integer, ALIGN_UP, ALIGN_DOWN, PTR_ALIGN_UP, and PTR_ALIGN_DOWN here. * include/libc-internal.h: Definitions of above macros moved from here. Don't include libc-diag.h anymore either. * posix/wordexp-test.c: Include stdint.h and libc-pointer-arith.h. Don't include libc-internal.h. * debug/pcprofile.c, elf/dl-tunables.c, elf/soinit.c, io/openat.c * io/openat64.c, misc/ptrace.c, nptl/pthread_clock_gettime.c * nptl/pthread_clock_settime.c, nptl/pthread_cond_common.c * string/strcoll_l.c, sysdeps/nacl/brk.c * sysdeps/unix/clock_settime.c * sysdeps/unix/sysv/linux/i386/get_clockfreq.c * sysdeps/unix/sysv/linux/ia64/get_clockfreq.c * sysdeps/unix/sysv/linux/powerpc/get_clockfreq.c * sysdeps/unix/sysv/linux/sparc/sparc64/get_clockfreq.c: Don't include libc-internal.h. * elf/get-dynamic-info.h, iconv/loop.c * iconvdata/iso-2022-cn-ext.c, locale/weight.h, locale/weightwc.h * misc/reboot.c, nis/nis_table.c, nptl_db/thread_dbP.h * nscd/connections.c, resolv/res_send.c, soft-fp/fmadf4.c * soft-fp/fmasf4.c, soft-fp/fmatf4.c, stdio-common/vfscanf.c * sysdeps/ieee754/dbl-64/e_lgamma_r.c * sysdeps/ieee754/dbl-64/k_rem_pio2.c * sysdeps/ieee754/flt-32/e_lgammaf_r.c * sysdeps/ieee754/flt-32/k_rem_pio2f.c * sysdeps/ieee754/ldbl-128/k_tanl.c * sysdeps/ieee754/ldbl-128ibm/k_tanl.c * sysdeps/ieee754/ldbl-96/e_lgammal_r.c * sysdeps/ieee754/ldbl-96/k_tanl.c, sysdeps/nptl/futex-internal.h: Include libc-diag.h instead of libc-internal.h. * elf/dl-load.c, elf/dl-reloc.c, locale/programs/locarchive.c * nptl/nptl-init.c, string/strcspn.c, string/strspn.c * malloc/malloc.c, sysdeps/i386/nptl/tls.h * sysdeps/nacl/dl-map-segments.h, sysdeps/x86_64/atomic-machine.h * sysdeps/unix/sysv/linux/spawni.c * sysdeps/x86_64/nptl/tls.h: Include libc-pointer-arith.h instead of libc-internal.h. * elf/get-dynamic-info.h, sysdeps/nacl/dl-map-segments.h * sysdeps/x86_64/atomic-machine.h: Add multiple include guard.
2017-03-01Miscellaneous low-risk changes preparing for _ISOMAC testsuite.Zack Weinberg
These are a grab bag of changes where the testsuite was using internal symbols of some variety, but this was straightforward to fix, and the fixed code should work with or without the change to compile the testsuite under _ISOMAC. Four of these are just more #include adjustments, but I want to highlight sysdeps/powerpc/fpu/tst-setcontext-fpscr.c, which appears to have been written before the advent of sys/auxv.h. I think a big chunk of this file could be replaced by a simple call to getauxval, but I'll let someone who actually has a powerpc machine to test on do that. dlfcn/tst-dladdr.c was including ldsodefs.h just so it could use DL_LOOKUP_ADDRESS to print an additional diagnostic; as requested by Carlos, I have removed this. math/test-misc.c was using #ifndef NO_LONG_DOUBLE, which is an internal configuration macro, to decide whether to do certain tests involving 'long double'. I changed the test to #if LDBL_MANT_DIG > DBL_MANT_DIG instead, which uses only public float.h macros and is equivalent on all supported platforms. (Note that NO_LONG_DOUBLE doesn't mean 'the compiler doesn't support long double', it means 'long double is the same as double'.) tst-writev.c has a configuration macro 'ARTIFICIAL_LIMIT' that the Makefiles are expected to define, and sysdeps/unix/sysv/linux/Makefile was using the internal __getpagesize in the definition; changed to sysconf(_SC_PAGESIZE) which is the POSIX equivalent. ia64-linux doesn't supply 'clone', only '__clone2', which is not defined in the public headers(!) All the other clone tests have local extern declarations of __clone2, but tst-clone.c doesn't; it was getting away with this because include/sched.h does declare __clone2. * nss/tst-cancel-getpwuid_r.c: Include nss.h. * string/strcasestr.c: No need to include config.h. * sysdeps/powerpc/fpu/tst-setcontext-fpscr.c: Include sys/auxv.h. Don't include sysdep.h. * sysdeps/powerpc/tst-set_ppr.c: Don't include dl-procinfo.h. * dlfcn/tst-dladdr.c: Don't include ldsodefs.h. Don't use DL_LOOKUP_ADDRESS. * math/test-misc.c: Instead of testing NO_LONG_DOUBLE, test whether LDBL_MANT_DIG is greater than DBL_MANT_DIG. * sysdeps/unix/sysv/linux/Makefile (CFLAGS-tst-writev.c): Use sysconf (_SC_PAGESIZE) instead of __getpagesize in definition of ARTIFICIAL_LIMIT. * sysdeps/unix/sysv/linux/tst-clone.c [__ia64__]: Add extern declaration of __clone2.
2017-02-25Split DIAG_* macros to new header libc-diag.h.Zack Weinberg
Quite a few tests include libc-internal.h just for the DIAG_* macros. Split those macros to their own file, which can be included safely in _ISOMAC mode. I also moved ignore_value, since it seems logically related, even though I didn't notice any tests needing it. Also add -Wnonnull suppressions to two tests that _should_ have them, but the error is masked when compiling against internal headers. * include/libc-diag.h: New file. Define ignore_value, DIAG_PUSH_NEEDS_COMMENT, DIAG_POP_NEEDS_COMMENT, DIAG_IGNORE_NEEDS_COMMENT, and DIAG_IGNORE_Os_NEEDS_COMMENT here. * include/libc-internal.h: Definitions of above macros moved from here. Include libc-diag.h. Add copyright notice. * malloc/tst-malloc.c, malloc/tst-memcheck.c, malloc/tst-realloc.c * misc/tst-error1.c, posix/tst-dir.c, stdio-common/bug21.c * stdio-common/scanf14.c, stdio-common/scanf4.c, stdio-common/scanf7.c * stdio-common/test-vfprintf.c, stdio-common/tst-printf.c * stdio-common/tst-printfsz.c, stdio-common/tst-sprintf.c * stdio-common/tst-unlockedio.c, stdio-common/tstdiomisc.c * stdlib/bug-getcontext.c, string/tester.c, string/tst-endian.c * time/tst-strptime2.c, wcsmbs/tst-wcstof.c: Include libc-diag.h instead of libc-internal.h. * stdlib/tst-environ.c: Include libc-diag.h. Suppress -Wnonnull for call to unsetenv (NULL). * nptl/tst-mutex1.c: Include libc-diag.h. Suppress -Wnonnull for call to pthread_mutexattr_destroy (NULL).
2017-02-16Add missing header files throughout the testsuite.Zack Weinberg
* crypt/md5.h: Test _LIBC with #if defined, not #if. * dirent/opendir-tst1.c: Include sys/stat.h. * dirent/tst-fdopendir.c: Include sys/stat.h. * dirent/tst-fdopendir2.c: Include stdlib.h. * dirent/tst-scandir.c: Include stdbool.h. * elf/tst-auditmod1.c: Include link.h and stddef.h. * elf/tst-tls15.c: Include stdlib.h. * elf/tst-tls16.c: Include stdlib.h. * elf/tst-tls17.c: Include stdlib.h. * elf/tst-tls18.c: Include stdlib.h. * iconv/tst-iconv6.c: Include endian.h. * iconvdata/bug-iconv11.c: Include limits.h. * io/test-utime.c: Include stdint.h. * io/tst-faccessat.c: Include sys/stat.h. * io/tst-fchmodat.c: Include sys/stat.h. * io/tst-fchownat.c: Include sys/stat.h. * io/tst-fstatat.c: Include sys/stat.h. * io/tst-futimesat.c: Include sys/stat.h. * io/tst-linkat.c: Include sys/stat.h. * io/tst-mkdirat.c: Include sys/stat.h and stdbool.h. * io/tst-mkfifoat.c: Include sys/stat.h and stdbool.h. * io/tst-mknodat.c: Include sys/stat.h and stdbool.h. * io/tst-openat.c: Include stdbool.h. * io/tst-readlinkat.c: Include sys/stat.h. * io/tst-renameat.c: Include sys/stat.h. * io/tst-symlinkat.c: Include sys/stat.h. * io/tst-unlinkat.c: Include stdbool.h. * libio/bug-memstream1.c: Include stdlib.h. * libio/bug-wmemstream1.c: Include stdlib.h. * libio/tst-fwrite-error.c: Include stdlib.h. * libio/tst-memstream1.c: Include stdlib.h. * libio/tst-memstream2.c: Include stdlib.h. * libio/tst-memstream3.c: Include stdlib.h. * malloc/tst-interpose-aux.c: Include stdint.h. * misc/tst-preadvwritev-common.c: Include sys/stat.h. * nptl/tst-basic7.c: Include limits.h. * nptl/tst-cancel25.c: Include pthread.h, not pthreadP.h. * nptl/tst-cancel4.c: Include stddef.h, limits.h, and sys/stat.h. * nptl/tst-cancel4_1.c: Include stddef.h. * nptl/tst-cancel4_2.c: Include stddef.h. * nptl/tst-cond16.c: Include limits.h. Use sysconf(_SC_PAGESIZE) instead of __getpagesize. * nptl/tst-cond18.c: Include limits.h. Use sysconf(_SC_PAGESIZE) instead of __getpagesize. * nptl/tst-cond4.c: Include stdint.h. * nptl/tst-cond6.c: Include stdint.h. * nptl/tst-stack2.c: Include limits.h. * nptl/tst-stackguard1.c: Include stddef.h. * nptl/tst-tls4.c: Include stdint.h. Don't include tls.h. * nptl/tst-tls4moda.c: Include stddef.h. Don't include stdio.h, unistd.h, or tls.h. * nptl/tst-tls4modb.c: Include stddef.h. Don't include stdio.h, unistd.h, or tls.h. * nptl/tst-tls5.h: Include stddef.h. Don't include stdlib.h or tls.h. * posix/tst-getaddrinfo2.c: Include stdio.h. * posix/tst-getaddrinfo5.c: Include stdio.h. * posix/tst-pathconf.c: Include sys/stat.h. * posix/tst-posix_fadvise-common.c: Include stdint.h. * posix/tst-preadwrite-common.c: Include sys/stat.h. * posix/tst-regex.c: Include stdint.h. Don't include spawn.h or spawn_int.h. * posix/tst-regexloc.c: Don't include spawn.h or spawn_int.h. * posix/tst-vfork3.c: Include sys/stat.h. * resolv/tst-bug18665-tcp.c: Include stdlib.h. * resolv/tst-res_hconf_reorder.c: Include stdlib.h. * resolv/tst-resolv-search.c: Include stdlib.h. * stdio-common/tst-fmemopen2.c: Include stdint.h. * stdio-common/tst-vfprintf-width-prec.c: Include stdlib.h. * stdlib/test-canon.c: Include sys/stat.h. * stdlib/tst-tls-atexit.c: Include stdbool.h. * string/test-memchr.c: Include stdint.h. * string/tst-cmp.c: Include stdint.h. * sysdeps/pthread/tst-timer.c: Include stdint.h. * sysdeps/unix/sysv/linux/tst-sync_file_range.c: Include stdint.h. * sysdeps/wordsize-64/tst-writev.c: Include limits.h and stdint.h. * sysdeps/x86_64/fpu/math-tests-arch.h: Include cpu-features.h. Don't include init-arch.h. * sysdeps/x86_64/multiarch/test-multiarch.h: Include cpu-features.h. Don't include init-arch.h. * sysdeps/x86_64/tst-auditmod10b.c: Include link.h and stddef.h. * sysdeps/x86_64/tst-auditmod3b.c: Include link.h and stddef.h. * sysdeps/x86_64/tst-auditmod4b.c: Include link.h and stddef.h. * sysdeps/x86_64/tst-auditmod5b.c: Include link.h and stddef.h. * sysdeps/x86_64/tst-auditmod6b.c: Include link.h and stddef.h. * sysdeps/x86_64/tst-auditmod6c.c: Include link.h and stddef.h. * sysdeps/x86_64/tst-auditmod7b.c: Include link.h and stddef.h. * time/clocktest.c: Include stdint.h. * time/tst-posixtz.c: Include stdint.h. * timezone/tst-timezone.c: Include stdint.h.
2017-02-06nptl: Remove COLORING_INCREMENTAdhemerval Zanella
This patch removes the COLORING_INCREMENT define and usage on allocatestack.c. It has not been used since 564cd8b67ec487f (glibc-2.3.3) by any architecture. The idea is to simplify the code by removing obsolete code. * nptl/allocatestack.c [COLORING_INCREMENT] (nptl_ncreated): Remove. (allocate_stack): Remove COLORING_INCREMENT usage. * nptl/stack-aliasing.h (COLORING_INCREMENT). Likewise. * sysdeps/i386/i686/stack-aliasing.h (COLORING_INCREMENT): Likewise.
2017-02-03Bug 20915: Do not initialize DTV of other threads.Alexandre Oliva
In _dl_nothread_init_static_tls() and init_one_static_tls() we must not touch the DTV of other threads since we do not have ownership of them. The DTV need not be initialized at this point anyway since only LD/GD accesses will use them. If LD/GD accesses occur they will take care to initialize their own thread's DTV. Concurrency comments were removed from the patch since they need to be reworked along with a full description of DTV ownership and when it is or is not safe to modify these structures. Alexandre Oliva's original patch and discussion: https://sourceware.org/ml/libc-alpha/2016-09/msg00512.html
2017-01-28Bug 20116: Fix use after free in pthread_create()Carlos O'Donell
The commit documents the ownership rules around 'struct pthread' and when a thread can read or write to the descriptor. With those ownership rules in place it becomes obvious that pd->stopped_start should not be touched in several of the paths during thread startup, particularly so for detached threads. In the case of detached threads, between the time the thread is created by the OS kernel and the creating thread checks pd->stopped_start, the detached thread might have already exited and the memory for pd unmapped. As a regression test we add a simple test which exercises this exact case by quickly creating detached threads with large enough stacks to ensure the thread stack cache is bypassed and the stacks are unmapped. Before the fix the testcase segfaults, after the fix it works correctly and completes without issue. For a detailed discussion see: https://www.sourceware.org/ml/libc-alpha/2017-01/msg00505.html
2017-01-27nptl: Add tst-robust-forkFlorian Weimer
2017-01-20Fix mutex pretty printer test and pretty printer output.Torvald Riegel
This fixes the mutex pretty printer so that, if the owner ID isn't recorded (such as in the current lock elision implementation), "Owner ID" will be shown as "Unknown" instead of 0. It also changes the mutex printer output so that it says "Acquired" instead of "Locked". The mutex tests are updated accordingly. In addition, this adds a paragraph to the "Known issues" section of the printers README explaining that the printer output isn't guaranteed to cover every detail. 2017-01-14 Martin Galvan <martingalvan@sourceware.org> * README.pretty-printers (Known issues): Warn about printers not always covering everything. * nptl/nptl-printers.py (MutexPrinter): Change output. * nptl/test-mutex-printers.py: Fix test and adapt to changed output.
2017-01-13Add compiler barriers around modifications of the robust mutex list.Torvald Riegel
Any changes to the per-thread list of robust mutexes currently acquired as well as the pending-operations entry are not simply sequential code but basically concurrent with any actions taken by the kernel when it tries to clean up after a crash. This is not quite like multi-thread concurrency but more like signal-handler concurrency. This patch fixes latent bugs by adding compiler barriers where necessary so that it is ensured that the kernel crash handling sees consistent data. This is meant to be easy to backport, so we do not use C11-style signal fences yet. * nptl/descr.h (ENQUEUE_MUTEX_BOTH, DEQUEUE_MUTEX): Add compiler barriers and comments. * nptl/pthread_mutex_lock.c (__pthread_mutex_lock_full): Likewise. * nptl/pthread_mutex_timedlock.c (pthread_mutex_timedlock): Likewise. * nptl/pthread_mutex_unlock.c (__pthread_mutex_unlock_full): Likewise.
2017-01-13robust mutexes: Fix broken x86 assembly by removing itTorvald Riegel
lll_robust_unlock on i386 and x86_64 first sets the futex word to FUTEX_WAITERS|0 before calling __lll_unlock_wake, which will set the futex word to 0. If the thread is killed between these steps, then the futex word will be FUTEX_WAITERS|0, and the kernel (at least current upstream) will not set it to FUTEX_OWNER_DIED|FUTEX_WAITERS because 0 is not equal to the TID of the crashed thread. The lll_robust_lock assembly code on i386 and x86_64 is not prepared to deal with this case because the fastpath tries to only CAS 0 to TID and not FUTEX_WAITERS|0 to TID; the slowpath simply waits until it can CAS 0 to TID or the futex_word has the FUTEX_OWNER_DIED bit set. This issue is fixed by removing the custom x86 assembly code and using the generic C code instead. However, instead of adding more duplicate code to the custom x86 lowlevellock.h, the code of the lll_robust* functions is inlined into the single call sites that exist for each of these functions in the pthread_mutex_* functions. The robust mutex paths in the latter have been slightly reorganized to make them simpler. This patch is meant to be easy to backport, so C11-style atomics are not used. [BZ #20985] * nptl/Makefile: Adapt. * nptl/pthread_mutex_cond_lock.c (LLL_ROBUST_MUTEX_LOCK): Remove. (LLL_ROBUST_MUTEX_LOCK_MODIFIER): New. * nptl/pthread_mutex_lock.c (LLL_ROBUST_MUTEX_LOCK): Remove. (LLL_ROBUST_MUTEX_LOCK_MODIFIER): New. (__pthread_mutex_lock_full): Inline lll_robust* functions and adapt. * nptl/pthread_mutex_timedlock.c (pthread_mutex_timedlock): Inline lll_robust* functions and adapt. * nptl/pthread_mutex_unlock.c (__pthread_mutex_unlock_full): Likewise. * sysdeps/nptl/lowlevellock.h (__lll_robust_lock_wait, __lll_robust_lock, lll_robust_cond_lock, __lll_robust_timedlock_wait, __lll_robust_timedlock, __lll_robust_unlock): Remove. * sysdeps/unix/sysv/linux/i386/lowlevellock.h (lll_robust_lock, lll_robust_cond_lock, lll_robust_timedlock, lll_robust_unlock): Remove. * sysdeps/unix/sysv/linux/x86_64/lowlevellock.h (lll_robust_lock, lll_robust_cond_lock, lll_robust_timedlock, lll_robust_unlock): Remove. * sysdeps/unix/sysv/linux/sparc/lowlevellock.h (__lll_robust_lock_wait, __lll_robust_lock, lll_robust_cond_lock, __lll_robust_timedlock_wait, __lll_robust_timedlock, __lll_robust_unlock): Remove. * nptl/lowlevelrobustlock.c: Remove file. * nptl/lowlevelrobustlock.sym: Likewise. * sysdeps/unix/sysv/linux/i386/lowlevelrobustlock.S: Likewise. * sysdeps/unix/sysv/linux/x86_64/lowlevelrobustlock.S: Likewise.
2017-01-10New pthread rwlock that is more scalable.Torvald Riegel
This replaces the pthread rwlock with a new implementation that uses a more scalable algorithm (primarily through not using a critical section anymore to make state changes). The fast path for rdlock acquisition and release is now basically a single atomic read-modify write or CAS and a few branches. See nptl/pthread_rwlock_common.c for details. * nptl/DESIGN-rwlock.txt: Remove. * nptl/lowlevelrwlock.sym: Remove. * nptl/Makefile: Add new tests. * nptl/pthread_rwlock_common.c: New file. Contains the new rwlock. * nptl/pthreadP.h (PTHREAD_RWLOCK_PREFER_READER_P): Remove. (PTHREAD_RWLOCK_WRPHASE, PTHREAD_RWLOCK_WRLOCKED, PTHREAD_RWLOCK_RWAITING, PTHREAD_RWLOCK_READER_SHIFT, PTHREAD_RWLOCK_READER_OVERFLOW, PTHREAD_RWLOCK_WRHANDOVER, PTHREAD_RWLOCK_FUTEX_USED): New. * nptl/pthread_rwlock_init.c (__pthread_rwlock_init): Adapt to new implementation. * nptl/pthread_rwlock_rdlock.c (__pthread_rwlock_rdlock_slow): Remove. (__pthread_rwlock_rdlock): Adapt. * nptl/pthread_rwlock_timedrdlock.c (pthread_rwlock_timedrdlock): Adapt. * nptl/pthread_rwlock_timedwrlock.c (pthread_rwlock_timedwrlock): Adapt. * nptl/pthread_rwlock_trywrlock.c (pthread_rwlock_trywrlock): Adapt. * nptl/pthread_rwlock_tryrdlock.c (pthread_rwlock_tryrdlock): Adapt. * nptl/pthread_rwlock_unlock.c (pthread_rwlock_unlock): Adapt. * nptl/pthread_rwlock_wrlock.c (__pthread_rwlock_wrlock_slow): Remove. (__pthread_rwlock_wrlock): Adapt. * nptl/tst-rwlock10.c: Adapt. * nptl/tst-rwlock11.c: Adapt. * nptl/tst-rwlock17.c: New file. * nptl/tst-rwlock18.c: New file. * nptl/tst-rwlock19.c: New file. * nptl/tst-rwlock2b.c: New file. * nptl/tst-rwlock8.c: Adapt. * nptl/tst-rwlock9.c: Adapt. * sysdeps/aarch64/nptl/bits/pthreadtypes.h (pthread_rwlock_t): Adapt. * sysdeps/arm/nptl/bits/pthreadtypes.h (pthread_rwlock_t): Adapt. * sysdeps/hppa/nptl/bits/pthreadtypes.h (pthread_rwlock_t): Adapt. * sysdeps/ia64/nptl/bits/pthreadtypes.h (pthread_rwlock_t): Adapt. * sysdeps/m68k/nptl/bits/pthreadtypes.h (pthread_rwlock_t): Adapt. * sysdeps/microblaze/nptl/bits/pthreadtypes.h (pthread_rwlock_t): Adapt. * sysdeps/mips/nptl/bits/pthreadtypes.h (pthread_rwlock_t): Adapt. * sysdeps/nios2/nptl/bits/pthreadtypes.h (pthread_rwlock_t): Adapt. * sysdeps/s390/nptl/bits/pthreadtypes.h (pthread_rwlock_t): Adapt. * sysdeps/sh/nptl/bits/pthreadtypes.h (pthread_rwlock_t): Adapt. * sysdeps/sparc/nptl/bits/pthreadtypes.h (pthread_rwlock_t): Adapt. * sysdeps/tile/nptl/bits/pthreadtypes.h (pthread_rwlock_t): Adapt. * sysdeps/unix/sysv/linux/alpha/bits/pthreadtypes.h (pthread_rwlock_t): Adapt. * sysdeps/unix/sysv/linux/powerpc/bits/pthreadtypes.h (pthread_rwlock_t): Adapt. * sysdeps/x86/bits/pthreadtypes.h (pthread_rwlock_t): Adapt. * nptl/nptl-printers.py (): Adapt. * nptl/nptl_lock_constants.pysym: Adapt. * nptl/test-rwlock-printers.py: Adapt. * nptl/test-rwlockattr-printers.c: Adapt. * nptl/test-rwlockattr-printers.py: Adapt.
2017-01-03Fix up tabs/spaces mismatchesMartin Galvan
Mixing them up breaks the gdb pretty printer tests. ChangeLog: 2017-01-02 Martin Galvan <martingalvan@sourceware.org> * nptl/nptl-printers.py: Fix tabs/spaces mismatches.
2017-01-01Update copyright dates not handled by scripts/update-copyrights.Joseph Myers
I've updated copyright dates in glibc for 2017. This is the patch for the changes not generated by scripts/update-copyrights and subsequent build / regeneration of generated files. Please remember to include 2017 in the dates for any new files added in future (which means updating any existing uncommitted patches you have that add new files to use the new copyright dates in them). * NEWS: Update copyright dates. * catgets/gencat.c (print_version): Likewise. * csu/version.c (banner): Likewise. * debug/catchsegv.sh: Likewise. * debug/pcprofiledump.c (print_version): Likewise. * debug/xtrace.sh (do_version): Likewise. * elf/ldconfig.c (print_version): Likewise. * elf/ldd.bash.in: Likewise. * elf/pldd.c (print_version): Likewise. * elf/sotruss.sh: Likewise. * elf/sprof.c (print_version): Likewise. * iconv/iconv_prog.c (print_version): Likewise. * iconv/iconvconfig.c (print_version): Likewise. * locale/programs/locale.c (print_version): Likewise. * locale/programs/localedef.c (print_version): Likewise. * login/programs/pt_chown.c (print_version): Likewise. * malloc/memusage.sh (do_version): Likewise. * malloc/memusagestat.c (print_version): Likewise. * malloc/mtrace.pl: Likewise. * manual/libc.texinfo: Likewise. * nptl/version.c (banner): Likewise. * nscd/nscd.c (print_version): Likewise. * nss/getent.c (print_version): Likewise. * nss/makedb.c (print_version): Likewise. * posix/getconf.c (main): Likewise. * scripts/test-installation.pl: Likewise. * sysdeps/unix/sysv/linux/lddlibc4.c (main): Likewise.
2017-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers
2016-12-31New condvar implementation that provides stronger ordering guarantees.Torvald Riegel
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.
2016-12-26Initialize the stack guard earlier when linking statically [BZ #7065]Nick Alcock
The address of the stack canary is stored in a per-thread variable, which means that we must ensure that the TLS area is intialized before calling any -fstack-protector'ed functions. For dynamically linked applications, we ensure this (in a later patch) by disabling -fstack-protector for the whole dynamic linker, but for static applications, the AT_ENTRY address is called directly by the kernel, so we must deal with the problem differently. In static appliations, __libc_setup_tls performs the TCB setup and TLS initialization, so this commit arranges for it to be called early and unconditionally. The call (and the stack guard initialization) is before the DL_SYSDEP_OSCHECK hook, which if set will probably call functions which are stack-protected (it does on Linux and NaCL too). We also move apply_irel up, so that we can still safely call functions that require ifuncs while in __libc_setup_tls (though if stack-protection is enabled we still have to avoid calling functions that are not stack-protected at this stage).
2016-12-23Fix failing pretty printer tests when CPPFLAGS has optimizations.Carlos O'Donell
The value of CPPFLAGS provided by the environment may have optimizations that interfere with the pretty printer test requirements. To override such optimizations the pretty printer tests must also specify CPPFLAGS. The existing pretty printer tests are fixed and the README.pretty-printers is updated with the new requirement.
2016-12-19Robust mutexes: Fix lost wake-up.Torvald Riegel
Assume that Thread 1 waits to acquire a robust mutex using futexes to block (and thus sets the FUTEX_WAITERS flag), and is unblocked when this mutex is released. If Thread 2 concurrently acquires the lock and is killed, Thread 1 can recover from the died owner but fail to restore the FUTEX_WAITERS flag. This can lead to a Thread 3 that also blocked using futexes at the same time as Thread 1 to not get woken up because FUTEX_WAITERS is not set anymore. The fix for this is to ensure that we continue to preserve the FUTEX_WAITERS flag whenever we may have set it or shared it with another thread. This is the same requirement as in the algorithm for normal mutexes, only that the robust mutexes need additional handling for died owners and thus preserving the FUTEX_WAITERS flag cannot be done just in the futex slowpath code. [BZ #20973] * nptl/pthread_mutex_lock.c (__pthread_mutex_lock_full): Fix lost wake-up in robust mutexes. * nptl/pthread_mutex_timedlock.c (pthread_mutex_timedlock): Likewise.
2016-12-13nptl/tst-cancel7: Add missing case labelFlorian Weimer
The label was lost during the conversion to the new test framework in commit c23de0aacbeaa7a091609b35764bed931475a16d, and the --command option is currently unused.
2016-12-09support: Introduce new subdirectory for test infrastructureFlorian Weimer
The new test driver in <support/test-driver.c> has feature parity with the old one. The main difference is that its hooking mechanism is based on functions and function pointers instead of macros. This commit also implements a new environment variable, TEST_COREDUMPS, which disables the code which disables coredumps (that is, it enables them if the invocation environment has not disabled them). <test-skeleton.c> defines wrapper functions so that it is possible to use existing macros with the new-style hook functionality. This commit changes only a few test cases to the new test driver, to make sure that it works as expected.
2016-12-08Add pretty printers for the NPTL lock typesMartin Galvan
This patch adds pretty printers for the following NPTL types: - pthread_mutex_t - pthread_mutexattr_t - pthread_cond_t - pthread_condattr_t - pthread_rwlock_t - pthread_rwlockattr_t To load the pretty printers into your gdb session, do the following: python import sys sys.path.insert(0, '/path/to/glibc/build/nptl/pretty-printers') end source /path/to/glibc/source/pretty-printers/nptl-printers.py You can check which printers are registered and enabled by issuing the 'info pretty-printer' gdb command. Printers should trigger automatically when trying to print a variable of one of the types mentioned above. The printers are architecture-independent, and were tested on an AMD64 running Ubuntu 14.04 and an x86 VM running Fedora 24. In order to work, the printers need to know the values of various flags that are scattered throughout pthread.h and pthreadP.h as enums and #defines. Since replicating these constants in the printers file itself would create a maintenance burden, I wrote a script called gen-py-const.awk that Makerules uses to extract the constants. This script is pretty much the same as gen-as-const.awk, except it doesn't cast the constant values to 'long' and is thorougly documented. The constants need only to be enumerated in a .pysym file, which is then referenced by a Make variable called gen-py-const-headers. As for the install directory, I discussed this with Mike Frysinger and Siddhesh Poyarekar, and we agreed that it can be handled in a separate patch, and shouldn't block merging of this one. In addition, I've written a series of test cases for the pretty printers. Each lock type (mutex, condvar and rwlock) has two test programs, one for itself and other for its related 'attributes' object. Each test program in turn has a PExpect-based Python script that drives gdb and compares its output to the expected printer's. The tests run on the glibc host, which is assumed to have both gdb and PExpect; if either is absent the tests will fail with code 77 (UNSUPPORTED). For cross-testing you should use cross-test-ssh.sh as test-wrapper. I've tested the printers on both native builds and a cross build using a Beaglebone Black running Debian, with the build system's filesystem shared with the board through NFS. Finally, I've written a README that explains all this and more. * INSTALL: Regenerated. * Makeconfig: Add comments and whitespace to make the control flow clearer. (+link-printers-tests, +link-pie-printers-tests, CFLAGS-printers-tests, installed-rtld-LDFLAGS, built-rtld-LDFLAGS, link-libc-rpath, link-libc-tests-after-rpath-link, link-libc-printers-tests): New. (rtld-LDFLAGS, rtld-tests-LDFLAGS, link-libc-tests-rpath-link, link-libc-tests): Use the new variables as required. * Makerules ($(py-const)): New rule. generated: Add $(py-const). * README.pretty-printers: New file. * Rules (tests-printers-programs, tests-printers-out, py-env): New. (others): Depend on $(py-const). (tests): Depend on $(tests-printers-programs) or $(tests-printers-out), as required. Pass $(tests-printers) to merge-test-results.sh. * manual/install.texi: Add requirements for testing the pretty printers. * nptl/Makefile (gen-py-const-headers, pretty-printers, tests-printers, CFLAGS-test-mutexattr-printers.c CFLAGS-test-mutex-printers.c, CFLAGS-test-condattr-printers.c, CFLAGS-test-cond-printers.c, CFLAGS-test-rwlockattr-printers.c CFLAGS-test-rwlock-printers.c, tests-printers-libs): Define. * nptl/nptl-printers.py: New file. * nptl/nptl_lock_constants.pysym: Likewise. * nptl/test-cond-printers.c: Likewise. * nptl/test-cond-printers.py: Likewise. * nptl/test-condattr-printers.c: Likewise. * nptl/test-condattr-printers.py: Likewise. * nptl/test-mutex-printers.c: Likewise. * nptl/test-mutex-printers.py: Likewise. * nptl/test-mutexattr-printers.c: Likewise. * nptl/test-mutexattr-printers.py: Likewise. * nptl/test-rwlock-printers.c: Likewise. * nptl/test-rwlock-printers.py: Likewise. * nptl/test-rwlockattr-printers.c: Likewise. * nptl/test-rwlockattr-printers.py: Likewise. * scripts/gen-py-const.awk: Likewise. * scripts/test_printers_common.py: Likewise. * scripts/test_printers_exceptions.py: Likewise.
2016-11-30Implement _dl_catch_error, _dl_signal_error in libc.so [BZ #16628]Florian Weimer
This change moves the main implementation of _dl_catch_error, _dl_signal_error to libc.so, where TLS variables can be used directly. This removes a writable function pointer from the rtld_global variable. For use during initial relocation, minimal implementations of these functions are provided in ld.so. These are eventually interposed by the libc.so implementations. This is implemented by compiling elf/dl-error-skeleton.c twice, via elf/dl-error.c and elf/dl-error-minimal.c. As a side effect of this change, the static version of dl-error.c no longer includes support for the _dl_signal_cerror/_dl_receive_error mechanism because it is only used in ld.so.
2016-11-24Remove cached PID/TID in cloneAdhemerval Zanella
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.
2016-11-08Consolidate lseek/lseek64/llseek implementationsAdhemerval Zanella
This patch consolidates all Linux lseek/lseek64/llseek implementation in on on sysdeps/unix/sysv/linux/lseek{64}.c. It also removes the llseek file and instead consolidate the LFS lseek implementation on lseek64.c as for other LFS symbols implementations. The general idea is: - lseek: ABIs that not define __OFF_T_MATCHES_OFF64_T will preferable use __NR__llseek if kernel supports it, otherwise they will use __NR_lseek. ABIs that defines __OFF_T_MATCHES_OFF64_T won't produce any symbol. - lseek64: ABIs with __OFF_T_MATCHES_OFF64_T will preferable use __NR_lseek (since it will use 64-bit arguments without low/high splitting) and __NR__llseek if __NR_lseek is not defined (for some ILP32 ports). - llseek: files will be removed and symbols will be aliased ot lseek64. ABI without __OFF_T_MATCHES_OFF64_T and without __NR_llseek (basically MIPS64n32 so far) are covered by building lseek with off_t as expected and lseek64 using __NR_lseek (as expected for off64_t being passed using 64-bit registers). For this consolidation I mantained the x32 assembly specific implementation because to correctly fix this it would required both the x32 fix for {INLINE,INTERNAL}_SYSCALL [1] and a wrapper to correctly subscribe it to return 64 bits instead of default 32 bits (as for times). It could a future cleanup. It is based on my previous {INTERNAL,INLINE}_SYSCALL_CALL macro [2], although it is mainly for simplification. Tested on x86_64, i686, aarch64, armhf, and powerpc64le. * nptl/Makefile (libpthread-routines): Remove ptw-llseek and add ptw-lseek64. * sysdeps/unix/sysv/linux/Makefile (sysdeps_routines): Remove llseek. * sysdeps/unix/sysv/linux/alpha/Makefile (sysdeps_routines): Likewise. * sysdeps/unix/sysv/linux/generic/wordsize-32/llseek.c: Remove file. * sysdeps/unix/sysv/linux/generic/wordsize-32/lseek.c: Remove file. * sysdeps/unix/sysv/linux/mips/mips64/llseek.c: Likewise. * sysdeps/unix/sysv/linux/llseek.c: Remove file. * sysdeps/unix/sysv/linux/lseek.c: New file. * sysdeps/unix/sysv/linux/lseek64.c: Add default Linux implementation. * sysdeps/unix/sysv/linux/mips/mips64/syscalls.list: Remove lseek and __libc_lseek64 from auto-generation. * sysdeps/unix/sysv/linux/wordsize-64/syscalls.list: Likewise. * sysdeps/unix/sysv/linux/x86_64/x32/lseek64.S: New file. [1] https://sourceware.org/ml/libc-alpha/2016-08/msg00443.html [2] https://sourceware.org/ml/libc-alpha/2016-08/msg00646.html
2016-11-07Write messages to stdout and use write_message instead of writeGabriel F. T. Gomes
Replaces calls to write on file descriptor 2 with calls to write_message, which writes to STDOUT_FILENO (1) and properly deals with the return of write.
2016-11-07Use write_message instead of writeGabriel F. T. Gomes
In the test cases, there are writes to stdout which do not check the result value. This patch replaces such occurrences with calls to write_message, which properly deals with the unused result. Tested for powerpc64le.
2016-10-28Document a behavior of an elided pthread_rwlock_unlockTulio Magno Quites Machado Filho
Explain that pthread_rwlock_unlock may crash if called on a lock not held by the current thread.
2016-10-07Use libc_ifunc macro for siglongjmp, longjmp in libpthread.Stefan Liebler
This patch uses the libc_ifunc macro to create already existing ifunc functions longjmp_ifunc, siglongjmp_ifunc if HAVE_IFUNC is defined. The s390 pt-longjmp.c includes the common pt-longjmp.c and uses strong_alias to create the longjmp, siglongjmp symbols for glibc version 2.19. ChangeLog: * nptl/pt-longjmp.c (DEFINE_LONGJMP): Use libc_ifunc macro. * sysdeps/unix/sysv/linux/s390/pt-longjmp.c (longjmp, siglongjmp): Use strong_alias to create symbols for glibc verison 2.19.
2016-10-07Use libc_ifunc macro for vfork in libpthread.Stefan Liebler
This patch uses the libc_ifunc macro to create already existing ifunc functions vfork_ifunc and __vfork_ifunc if HAVE_IFUNC is defined. ChangeLog: * nptl/pt-vfork.c (DEFINE_VFORK): Use libc_ifunc macro.
2016-10-07Use libc_ifunc macro for system in libpthread.Stefan Liebler
This patch uses the libc_ifunc macro to create already existing ifunc function system_ifunc if HAVE_IFUNC is defined. ChangeLog: * nptl/pt-system.c (system_ifunc): Use libc_ifunc macro.
2016-09-21[PR19826] fix non-LE TLS in static programsAlexandre Oliva
An earlier fix for TLS dropped early initialization of DTV entries for modules using static TLS, leaving it for __tls_get_addr to set them up. That worked on platforms that require the GD access model to be relaxed to LE in the main executable, but it caused a regression on platforms that allow GD in the main executable, particularly in statically-linked programs: they use a custom __tls_get_addr that does not update the DTV, which fails when the DTV early initialization is not performed. In static programs, __libc_setup_tls performs the DTV initialization for the main thread, but the DTV of other threads is set up in _dl_allocate_tls_init, so that's the fix that matters. Restoring the initialization in the remaining functions modified by this patch was just for uniformity. It's not clear that it is ever needed: even on platforms that allow GD in the main executable, the dynamically-linked version of __tls_get_addr would set up the DTV entries, even for static TLS modules, while updating the DTV counter. for ChangeLog [BZ #19826] * elf/dl-tls.c (_dl_allocate_tls_init): Restore DTV early initialization of static TLS entries. * elf/dl-reloc.c (_dl_nothread_init_static_tls): Likewise. * nptl/allocatestack.c (init_one_static_tls): Likewise.
2016-09-20posix: Correctly enable/disable cancellation on Linux posix_spawnAdhemerval Zanella
This patch correctly enable and disable asynchronous cancellation on Linux posix_spawn. Current code invert the logic by enabling and disabling instead. It also adds a new test to check if posix_spawn is not a cancellation entrypoint. Checked on x86_64, i686, powerpc64le, and aarch64. * nptl/Makefile (tests): Add tst-exec5. * nptl/tst-exec5.c: New file. * sysdeps/unix/sysv/linux/spawni.c (__spawni): Correctly enable and disable asynchronous cancellation.
2016-09-15nptl: Consolidate sem_init implementationsAdhemerval Zanella
Current sparc32 sem_init and default one only differ on sem.newsem.pad initialization. This patch removes sparc32 and sparc32v9 sem_init arch specific implementation and set sparc32 to use nptl default one. The default implementation sets the required sem.newsem.pad to 0 (which is ununsed in other architectures). I checked on i686 and a sparc32v9 build. * nptl/sem_init.c (sem_init): Init pad value to 0. * sysdeps/sparc/sparc32/sem_init.c: Remove file. * sysdeps/sparc/sparc32/sparcv9/sem_init.c: Likewise.
2016-09-15nptl: Fix sem_wait and sem_timedwait cancellation (BZ#18243)Adhemerval Zanella
This patch fixes both sem_wait and sem_timedwait cancellation point for uncontended case. In this scenario only atomics are involved and thus the futex cancellable call is not issue and a pending cancellation signal is not handled. The fix is straighforward by calling pthread_testcancel is both function start. Although it would be simpler to call CANCELLATION_P directly, I decided to add an internal pthread_testcancel alias and use it to export less internal implementation on such function. A possible change on how pthread_testcancel is internally implemented would lead to either continue to force use CANCELLATION_P or to adjust its every use. GLIBC testcase also does have tests for uncontended cases, test-cancel12 and test-cancel14.c, however both are flawed by adding another cancellation point just after thread pthread_cleanup_pop: 47 static void * 48 tf (void *arg) 49 { 50 pthread_cleanup_push (cleanup, NULL); 51 52 int e = pthread_barrier_wait (&bar); 53 if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD) 54 { 55 puts ("tf: 1st barrier_wait failed"); 56 exit (1); 57 } 58 59 /* This call should block and be cancelable. */ 60 sem_wait (&sem); 61 62 pthread_cleanup_pop (0); 63 64 puts ("sem_wait returned"); 65 66 return NULL; 67 } So sem_{timed}wait does not act on cancellation, pthread_cleanup_pop executes 'cleanup' and then 'puts' acts on cancellation. Since pthread_cleanup_pop removed the clean-up handler, it will ran only once and thus it won't accuse an error to indicate sem_wait has not acted on the cancellation signal. This patch also fixes this behavior by removing the cancellation point 'puts'. It also adds some cleanup on all sem_{timed}wait cancel tests. It partially fixes BZ #18243. Checked on x86_64. [BZ #18243] * nptl/pthreadP.h (__pthread_testcancel): Add prototype and hidden_proto. * nptl/pthread_testcancel.c (pthread_cancel): Add internal aliais definition. * nptl/sem_timedwait.c (sem_timedwait): Add cancellation check for uncontended case. * nptl/sem_wait.c (__new_sem_wait): Likewise. * nptl/tst-cancel12.c (cleanup): Remove wrong cancellation point. (tf): Fix check for uncontended case. (do_test): Likewise. * nptl/tst-cancel13.c (cleanup): Remove wrong cancellation point. (tf): Fix check for uncontended case. (do_test): Likewise. * nptl/tst-cancel14.c (cleanup): Remove wrong cancellation point. (tf): Fix check for uncontended case. (do_test): Likewise. * nptl/tst-cancel15.c (cleanup): Remove wrong cancellation point. (tf): Fix check for uncontended case. (do_test): Likewise.
2016-09-15nptl: Set sem_open as a non cancellation point (BZ #15765)Adhemerval Zanella
This patch changes sem_open to not act as a cancellation point. Cancellation is disable at start and reenable in function exit. It fixes BZ #15765. Tested on x86_64 and i686. [BZ #15765] * nptl/Makefile (tests): Add tst-sem16. * nptl/tst-sem16.c: New file. * nptl/sem_open.c (sem_open): Disable asynchronous cancellation.
2016-09-15nptl: Consolidate sem_open implementationsAdhemerval Zanella
Current sparc32 sem_open and default one only differ on: 1. Default one contains a 'futex_supports_pshared' check. 2. sem.newsem.pad is initialized to zero. This patch removes sparc32 and sparc32v9 sem_open arch specific implementation and instead set sparc32 to use nptl default one. Using 1. is fine since it should always evaluate 0 for Linux (an optimized away by the compiler). Adding 2. to default implementation should be ok since 'pad' field is used mainly on sparc32 code. I checked on i686 and checked a sparc32v9 build. * nptl/sem_open.c (sem_open): Init pad value to 0. * sysdeps/sparc/sparc32/sem_open.c: Remove file. * sysdeps/sparc/sparc32/sparcv9/sem_open.c: Likewise.
2016-09-14Remove the ptw-% patternsFlorian Weimer
Nothing depends on the PTW macro anymore, so the mechanism to define PTW for recompliations of libc routines is no longer needed. The source files are still recompiled for the nptl directory, just without the “ptw-” prefix. (Reducing the number of pattern rules in sysd-rules is critical for improving make performance.)
2016-08-26malloc: Simplify static malloc interposition [BZ #20432]Florian Weimer
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.
2016-08-26nptl: Avoid expected SIGALRM in most tests [BZ #20432]Florian Weimer
Before this change, several tests did not detect early deadlocks because they used SIGALRM as the expected signal, and they ran for the full default TIMEOUT seconds. This commit adds a new delayed_exit function to the test skeleton, along with several error-checking wrappers to pthread functions. Additional error checking is introduced into several tests.
2016-08-17nptl/tst-once5: Reduce time to expected failureFlorian Weimer
2016-08-16nptl/tst-tls3-malloc: Force freeing of thread stacksFlorian Weimer
It turns out that due to the reduced stack size in tst-tls3 and the (fixed) default stack cache size, allocated TLS variables are never freed, so the test coverage for tst-tls3-malloc is less than complete. This change increases the thread stack size for tst-tls3-malloc only, to make sure thread stacks and TLS variables are freed.
2016-08-03elf: Do not use memalign for TCB/TLS blocks allocation [BZ #17730]Florian Weimer
Instead, call malloc and explicitly align the pointer. There is no external location to store the original (unaligned) pointer, and this commit increases the allocation size to store the pointer at a fixed location relative to the TCB pointer. The manual alignment means that some space goes unused which was previously made available for subsequent allocations. However, in the TLS_DTV_AT_TP case, the manual alignment code avoids aligning the pre-TCB to the TLS block alignment. (Even while using memalign, the allocation had some unused padding in front.) This concludes the removal of memalign calls from the TLS code, and the new tst-tls3-malloc test verifies that only core malloc routines are used.
2016-08-03elf: Avoid using memalign for TLS allocations [BZ #17730]Florian Weimer
Instead of a flag which indicates the pointer can be freed, dtv_t now includes the pointer which should be freed. Due to padding, the size of dtv_t does not increase. To avoid using memalign, the new allocate_dtv_entry function allocates a sufficiently large buffer so that a sub-buffer can be found in it which starts with an aligned pointer. Both the aligned and original pointers are kept, the latter for calling free later.
2016-07-11Revert "Add pretty printers for the NPTL lock types"Siddhesh Poyarekar
This reverts commit 62ce266b0b261def2c6329be9814ffdcc11964d6. The change is not mature enough because it needs the following fixes: 1. Redirect test output to a file like other tests 2. Eliminate the need to use a .gdbinit because distributions will break without it. I should have caught that but I was in too much of a hurry to get the patch in :/ 3. Feature checking during configure to determine things like minimum required gdb version, python-pexpect version, etc. to make sure that tests work correctly.