There is a data-dependency between the fields of struct l_reloc_result
and the field used as the initialization guard. Users of the guard
expect writes to the structure to be observable when they also observe
the guard initialized. The solution for this problem is to use an acquire
and release load and store to ensure previous writes to the structure are
observable if the guard is initialized.
The previous implementation used DL_FIXUP_VALUE_ADDR (l_reloc_result->addr)
as the initialization guard, making it impossible for some architectures
to load and store it atomically, i.e. hppa and ia64, due to its larger size.
This commit adds an unsigned int to l_reloc_result to be used as the new
initialization guard of the struct, making it possible to load and store
it atomically in all architectures. The fix ensures that the values
observed in l_reloc_result are consistent and do not lead to crashes.
The algorithm is documented in the code in elf/dl-runtime.c
(_dl_profile_fixup). Not all data races have been eliminated.
Tested with build-many-glibcs and on powerpc, powerpc64, and powerpc64le.
[BZ #23690]
* elf/dl-runtime.c (_dl_profile_fixup): Guarantee memory
modification order when accessing reloc_result->addr.
* include/link.h (reloc_result): Add field init.
* nptl/Makefile (tests): Add tst-audit-threads.
(modules-names): Add tst-audit-threads-mod1 and
tst-audit-threads-mod2.
Add rules to build tst-audit-threads.
* nptl/tst-audit-threads-mod1.c: New file.
* nptl/tst-audit-threads-mod2.c: Likewise.
* nptl/tst-audit-threads.c: Likewise.
* nptl/tst-audit-threads.h: Likewise.
Signed-off-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
All the required code already existed, and some of it was already
running.
AT_SYSINFO_EHDR is processed if NEED_DL_SYSINFO_DSO is defined, but it
looks like it always is. The call to setup_vdso is also unconditional,
so all that was left to do was setup the function pointers and use
them. This patch just deletes some #ifdef to enable that.
[BZ #19767]
* nptl/Makefile (tests-static): Add tst-cond11-static.
(tests): Likewise.
* nptl/tst-cond11-static.c: New File.
* sysdeps/unix/sysv/linux/Makefile (tests-static): Add
tst-affinity-static.
(tests): Likewise.
* sysdeps/unix/sysv/linux/sysdep-vdso.h: Check USE_VSYSCALL
instead of SHARED.
* sysdeps/unix/sysv/linux/sysdep.h (ALWAYS_USE_VSYSCALL): New.
(USE_VSYSCALL): Likewise.
* sysdeps/unix/sysv/linux/tst-affinity-static.c: New file.
* sysdeps/unix/sysv/linux/x86/libc-vdso.h: Check USE_VSYSCALL
instead of SHARED.
* sysdeps/unix/sysv/linux/x86_64/init-first.c: Don't check
SHARED.
* sysdeps/unix/sysv/linux/x86_64/sysdep.h (ALWAYS_USE_VSYSCALL):
New.
The race leads either to pthread_mutex_destroy returning EBUSY
or triggering an assertion (See description in bugzilla).
This patch is fixing the race by ensuring that the elision path is
used in all cases if elision is enabled by the GLIBC_TUNABLES framework.
The __kind variable in struct __pthread_mutex_s is accessed concurrently.
Therefore we are now using the atomic macros.
The new testcase tst-mutex10 is triggering the race on s390x and intel.
Presumably also on power, but I don't have access to a power machine
with lock-elision. At least the code for power is the same as on the other
two architectures.
ChangeLog:
[BZ #23275]
* nptl/tst-mutex10.c: New File.
* nptl/Makefile (tests): Add tst-mutex10.
(tst-mutex10-ENV): New variable.
* sysdeps/unix/sysv/linux/s390/force-elision.h: (FORCE_ELISION):
Ensure that elision path is used if elision is available.
* sysdeps/unix/sysv/linux/powerpc/force-elision.h (FORCE_ELISION):
Likewise.
* sysdeps/unix/sysv/linux/x86/force-elision.h: (FORCE_ELISION):
Likewise.
* nptl/pthreadP.h (PTHREAD_MUTEX_TYPE, PTHREAD_MUTEX_TYPE_ELISION)
(PTHREAD_MUTEX_PSHARED): Use atomic_load_relaxed.
* nptl/pthread_mutex_consistent.c (pthread_mutex_consistent): Likewise.
* nptl/pthread_mutex_getprioceiling.c (pthread_mutex_getprioceiling):
Likewise.
* nptl/pthread_mutex_lock.c (__pthread_mutex_lock_full)
(__pthread_mutex_cond_lock_adjust): Likewise.
* nptl/pthread_mutex_setprioceiling.c (pthread_mutex_setprioceiling):
Likewise.
* nptl/pthread_mutex_timedlock.c (__pthread_mutex_timedlock): Likewise.
* nptl/pthread_mutex_trylock.c (__pthread_mutex_trylock): Likewise.
* nptl/pthread_mutex_unlock.c (__pthread_mutex_unlock_full): Likewise.
* sysdeps/nptl/bits/thread-shared-types.h (struct __pthread_mutex_s):
Add comments.
* nptl/pthread_mutex_destroy.c (__pthread_mutex_destroy):
Use atomic_load_relaxed and atomic_store_relaxed.
* nptl/pthread_mutex_init.c (__pthread_mutex_init):
Use atomic_store_relaxed.
This patch adds to testsuite new test cases to test all new introduced
C11 threads functions, types and macros are tested.
Checked with a build for all major ABI (aarch64-linux-gnu, alpha-linux-gnu,
arm-linux-gnueabi, i386-linux-gnu, ia64-linux-gnu, m68k-linux-gnu,
microblaze-linux-gnu [1], mips{64}-linux-gnu, nios2-linux-gnu,
powerpc{64le}-linux-gnu, s390{x}-linux-gnu, sparc{64}-linux-gnu,
and x86_64-linux-gnu).
Also ran a full check on aarch64-linux-gnu, x86_64-linux-gnu, i686-linux-gnu,
arm-linux-gnueabhf, and powerpc64le-linux-gnu.
Adhemerval Zanella <adhemerval.zanella@linaro.org>
Juan Manuel Torres Palma <jmtorrespalma@gmail.com>
[BZ #14092]
* nptl/Makefile (tests): Add new test files.
* nptl/tst-call-once.c : New file. Tests C11 functions and types.
* nptl/tst-cnd-basic.c: Likewise.
* nptl/tst-cnd-broadcast.c: Likewise.
* nptl/tst-cnd-timedwait.c: Likewise.
* nptl/tst-mtx-basic.c: Likewise.
* nptl/tst-mtx-recursive.c: Likewise.
* nptl/tst-mtx-timedlock.c: Likewise.
* nptl/tst-mtx-trylock.c: Likewise.
* nptl/tst-thrd-basic.c: Likewise.
* nptl/tst-thrd-detach.c: Likewise.
* nptl/tst-thrd-sleep.c: Likewise.
* nptl/tst-tss-basic.c: Likewise.
This patch adds the tss_* definitions from C11 threads (ISO/IEC 9899:2011),
more specifically tss_create, tss_delete, tss_get, tss_set, and required
types.
Mostly of the definitions are composed based on POSIX conterparts, including
tss_t (pthread_key_t).
Checked with a build for all major ABI (aarch64-linux-gnu, alpha-linux-gnu,
arm-linux-gnueabi, i386-linux-gnu, ia64-linux-gnu, m68k-linux-gnu,
microblaze-linux-gnu [1], mips{64}-linux-gnu, nios2-linux-gnu,
powerpc{64le}-linux-gnu, s390{x}-linux-gnu, sparc{64}-linux-gnu,
and x86_64-linux-gnu).
Also ran a full check on aarch64-linux-gnu, x86_64-linux-gnu, i686-linux-gnu,
arm-linux-gnueabhf, and powerpc64le-linux-gnu.
[BZ #14092]
* conform/data/threads.h-data (thread_local): New macro.
(TSS_DTOR_ITERATIONS): Likewise.
(tss_t): New type.
(tss_dtor_t): Likewise.
(tss_create): New function.
(tss_get): Likewise.
(tss_set): Likewise.
(tss_delete): Likewise.
* nptl/Makefile (libpthread-routines): Add tss_create, tss_delete,
tss_get, and tss_set objects.
* nptl/Versions (libpthread) [GLIBC_2.28]: Likewise.
* nptl/tss_create.c: New file.
* nptl/tss_delete.c: Likewise.
* nptl/tss_get.c: Likewise.
* nptl/tss_set.c: Likewise.
* sysdeps/nptl/threads.h (thread_local): New define.
(TSS_DTOR_ITERATIONS): Likewise.
(tss_t): New typedef.
(tss_dtor_t): Likewise.
(tss_create): New prototype.
(tss_get): Likewise.
(tss_set): Likewise.
(tss_delete): Likewise.
This patch adds the cnd_* definitions from C11 threads (ISO/IEC 9899:2011),
more specifically cnd_broadcast, cnd_destroy, cnd_init, cnd_signal,
cnd_timedwait, cnd_wait, and required types.
Mostly of the definitions are composed based on POSIX conterparts, and
cnd_t is also based on internal pthreads fields, but with distinct internal
layout to avoid possible issues with code interchange (such as trying to pass
POSIX structure on C11 functions and to avoid inclusion of pthread.h). The
idea is to make it possible to share POSIX internal implementation for mostly
of the code making adjust where only required.
Checked with a build for all major ABI (aarch64-linux-gnu, alpha-linux-gnu,
arm-linux-gnueabi, i386-linux-gnu, ia64-linux-gnu, m68k-linux-gnu,
microblaze-linux-gnu [1], mips{64}-linux-gnu, nios2-linux-gnu,
powerpc{64le}-linux-gnu, s390{x}-linux-gnu, sparc{64}-linux-gnu,
and x86_64-linux-gnu).
Also ran a full check on aarch64-linux-gnu, x86_64-linux-gnu, i686-linux-gnu,
arm-linux-gnueabhf, and powerpc64le-linux-gnu.
[BZ #14092]
* conform/data/threads.h-data (cnd_t): New type.
(cnd_init): New function.
(cnd_signal): Likewise.
(cnd_broadcast): Likewise.
(cnd_wait): Likewise.
(cnd_timedwait): Likewise.
(cnd_destroy): Likewise.
* nptl/Makefile (libpthread-routines): Add cnd_broadcast,
cnd_destroy, cnd_init, cnd_signal, cnd_timedwait, and cnd_wait
object.
* nptl/Versions (libpthread) [GLIBC_2.28]: Likewise.
* nptl/cnd_broadcast.c: New file.
* nptl/cnd_destroy.c: Likewise.
* nptl/cnd_init.c: Likewise.
* nptl/cnd_signal.c: Likewise.
* nptl/cnd_timedwait.c: Likewise.
* nptl/cnd_wait.c: Likewise.
* sysdeps/nptl/threads.h (cnd_t): New type.
(cnd_init): New prototype.
(cnd_signa): Likewise.
(cnd_broadcast): Likewise.
(cnd_wait): Likewise.
(cnd_timedwait): Likewise.
(cnd_destroy): Likewise.
This patch adds the call_* definitions from C11 threads (ISO/IEC 9899:2011),
more specifically call_once and required types.
Mostly of the definitions are composed based on POSIX conterparts,including
once_flag (pthread_once_t). The idea is to make possible to share POSIX
internal implementations for mostly of the code (and making adjustment only
when required).
Checked with a build for all major ABI (aarch64-linux-gnu, alpha-linux-gnu,
arm-linux-gnueabi, i386-linux-gnu, ia64-linux-gnu, m68k-linux-gnu,
microblaze-linux-gnu [1], mips{64}-linux-gnu, nios2-linux-gnu,
powerpc{64le}-linux-gnu, s390{x}-linux-gnu, sparc{64}-linux-gnu,
and x86_64-linux-gnu).
Also ran a full check on aarch64-linux-gnu, x86_64-linux-gnu, i686-linux-gnu,
arm-linux-gnueabhf, and powerpc64le-linux-gnu.
[BZ #14092]
* conform/data/threads.h-data (ONCE_FLAG_INIT): New macro.
(once_flag): New type.
(call_once): New function.
* nptl/Makefile (libpthread-routines): Add call_once object.
* nptl/Versions (libphread) [GLIBC_2.28]: Add call_once symbol.
* nptl/call_once.c: New file.
* sysdeps/nptl/threads.h (ONCE_FLAG_INIT): New define.
(once_flag): New type.
(call_once): New prototype.
This patch adds the mtx_* definitions from C11 threads (ISO/IEC 9899:2011),
more specifically mtx_init, mtx_destroy, mtx_lock, mtx_timedlock, mtx_trylock,
mtx_unlock, and required types.
Mostly of the definitions are composed based on POSIX conterparts, and mtx_t
is also based on internal pthread fields, but with a distinct internal layout
to avoid possible issues with code interchange (such as trying to pass POSIX
structure on C11 functions and to avoid inclusion of pthread.h). The idea
is to make possible to share POSIX internal implementations for mostly of
the code (and making adjustment only when required).
Checked with a build for all major ABI (aarch64-linux-gnu, alpha-linux-gnu,
arm-linux-gnueabi, i386-linux-gnu, ia64-linux-gnu, m68k-linux-gnu,
microblaze-linux-gnu [1], mips{64}-linux-gnu, nios2-linux-gnu,
powerpc{64le}-linux-gnu, s390{x}-linux-gnu, sparc{64}-linux-gnu,
and x86_64-linux-gnu).
Also ran a full check on aarch64-linux-gnu, x86_64-linux-gnu, i686-linux-gnu,
arm-linux-gnueabhf, and powerpc64le-linux-gnu.
[BZ #14092]
* conform/data/threads.h-data (mtx_plain): New constant.
(mtx_recursive): Likewise.
(mtx_timed): Likewise.
(mtx_t): New type.
(mtx_init): New function.
(mtx_lock): Likewise.
(mtx_timedlock): Likewise.
(mtx_trylock): Likewise.
(mtx_unlock): Likewise.
(mtx_destroy): Likewise.
* nptl/Makefile (libpthread-routines): Add mtx_destroy, mtx_init,
mtx_lock, mtx_timedlock, mtx_trylock, and mtx_unlock object.
* nptl/Versions (libpthread) [GLIBC_2.28]): Add mtx_init, mtx_lock,
mtx_timedlock, mtx_trylock, mtx_unlock, and mtx_destroy.
* nptl/mtx_destroy.c: New file.
* nptl/mtx_init.c: Likewise.
* nptl/mtx_lock.c: Likewise.
* nptl/mtx_timedlock.c: Likewise.
* nptl/mtx_trylock.c: Likewise.
* nptl/mtx_unlock.c: Likewise.
* sysdeps/nptl/threads.h (mtx_plain): New enumeration.
(mtx_recursive): Likewise.
(mtx_timed): Likewise.
(mtx_t): New type.
(mtx_init): New prototype.
(mtx_lock): Likewise.
(mtx_timedlock): Likewise.
(mtx_trylock): Likewise.
(mtx_unlock): Likewise.
(mtx_destroy): Likewise.
This patch adds the thrd_* definitions from C11 threads (ISO/IEC 9899:2011),
more specifically thrd_create, thrd_curent, rhd_detach, thrd_equal,
thrd_exit, thrd_join, thrd_sleep, thrd_yield, and required types.
Mostly of the definitions are composed based on POSIX conterparts, such as
thrd_t (using pthread_t). For thrd_* function internally direct
POSIX pthread call are used with the exceptions:
1. thrd_start uses pthread_create internal implementation, but changes
how to actually calls the start routine. This is due the difference
in signature between POSIX and C11, where former return a 'void *'
and latter 'int'.
To avoid calling convention issues due 'void *' to int cast, routines
from C11 threads are started slight different than default pthread one.
Explicit cast to expected return are used internally on pthread_create
and the result is stored back to void also with an explicit cast.
2. thrd_sleep uses nanosleep internal direct syscall to avoid clobbering
errno and to handle expected standard return codes. It is a
cancellation entrypoint to be consistent with both thrd_join and
cnd_{timed}wait.
3. thrd_yield also uses internal direct syscall to avoid errno clobbering.
Checked with a build for all major ABI (aarch64-linux-gnu, alpha-linux-gnu,
arm-linux-gnueabi, i386-linux-gnu, ia64-linux-gnu, m68k-linux-gnu,
microblaze-linux-gnu [1], mips{64}-linux-gnu, nios2-linux-gnu,
powerpc{64le}-linux-gnu, s390{x}-linux-gnu, sparc{64}-linux-gnu,
and x86_64-linux-gnu).
Also ran a full check on aarch64-linux-gnu, x86_64-linux-gnu, i686-linux-gnu,
arm-linux-gnueabhf, and powerpc64le-linux-gnu.
[BZ #14092]
* conform/Makefile (conformtest-headers-ISO11): Add threads.h.
(linknamespace-libs-ISO11): Add libpthread.a.
* conform/data/threads.h-data: New file: add C11 thrd_* types and
functions.
* include/stdc-predef.h (__STDC_NO_THREADS__): Remove definition.
* nptl/Makefile (headers): Add threads.h.
(libpthread-routines): Add new C11 thread thrd_create, thrd_current,
thrd_detach, thrd_equal, thrd_exit, thrd_join, thrd_sleep, and
thrd_yield.
* nptl/Versions (libpthread) [GLIBC_2.28]): Add new C11 thread
thrd_create, thrd_current, thrd_detach, thrd_equal, thrd_exit,
thrd_join, thrd_sleep, and thrd_yield symbols.
* nptl/descr.h (struct pthread): Add c11 field.
* nptl/pthreadP.h (ATTR_C11_THREAD): New define.
* nptl/pthread_create.c (START_THREAD_DEFN): Call C11 thread start
routine with expected function prototype.
(__pthread_create_2_1): Add C11 threads check based on attribute
value.
* sysdeps/unix/sysdep.h (INTERNAL_SYSCALL_CANCEL): New macro.
* nptl/thrd_create.c: New file.
* nptl/thrd_current.c: Likewise.
* nptl/thrd_detach.c: Likewise.
* nptl/thrd_equal.c: Likewise.
* nptl/thrd_exit.c: Likewise.
* nptl/thrd_join.c: Likewise.
* nptl/thrd_priv.h: Likewise.
* nptl/thrd_sleep.c: Likewise.
* nptl/thrd_yield.c: Likewise.
* include/threads.h: Likewise.
The __libc_freeres framework does not extend to non-libc.so objects.
This causes problems in general for valgrind and mtrace detecting
unfreed objects in both libdl.so and libpthread.so. This change is
a pre-requisite to properly moving the malloc hooks out of malloc
since such a move now requires precise accounting of all allocated
data before destructors are run.
This commit adds a proper hook in libc.so.6 for both libdl.so and
for libpthread.so, this ensures that shm-directory.c which uses
freeit () to free memory is called properly. We also remove the
nptl_freeres hook and fall back to using weak-ref-and-check idiom
for a loaded libpthread.so, thus making this process similar for
all DSOs.
Lastly we follow best practice and use explicit free calls for
both libdl.so and libpthread.so instead of the generic hook process
which has undefined order.
Tested on x86_64 with no regressions.
Signed-off-by: DJ Delorie <dj@redhat.com>
Signed-off-by: Carlos O'Donell <carlos@redhat.com>
This patch fixes the OFD ("file private") locks for architectures that
support non-LFS flock definition (__USE_FILE_OFFSET64 not defined). The
issue in this case is both F_OFD_{GETLK,SETLK,SETLKW} and
F_{SET,GET}L{W}K64 expects a flock64 argument and when using old
F_OFD_* flags with a non LFS flock argument the kernel might interpret
the underlying data wrongly. Kernel idea originally was to avoid using
such flags in non-LFS syscall, but since GLIBC uses fcntl with LFS
semantic as default it is possible to provide the functionality and
avoid the bogus struct kernel passing by adjusting the struct manually
for the required flags.
The idea follows other LFS interfaces that provide two symbols:
1. A new LFS fcntl64 is added on default ABI with the usual macros to
select it for FILE_OFFSET_BITS=64.
2. The Linux non-LFS fcntl use a stack allocated struct flock64 for
F_OFD_{GETLK,SETLK,SETLKW} copy the results on the user provided
struct.
3. Keep a compat symbol with old broken semantic for architectures
that do not define __OFF_T_MATCHES_OFF64_T.
So for architectures which defines __USE_FILE_OFFSET64, fcntl64 will
aliased to fcntl and no adjustment would be required. So to actually
use F_OFD_* with LFS support the source must be built with LFS support
(_FILE_OFFSET_BITS=64).
Also F_OFD_SETLKW command is handled a cancellation point, as for
F_SETLKW{64}.
Checked on x86_64-linux-gnu and i686-linux-gnu.
[BZ #20251]
* NEWS: Mention fcntl64 addition.
* csu/check_fds.c: Replace __fcntl_nocancel by __fcntl64_nocancel.
* login/utmp_file.c: Likewise.
* sysdeps/posix/fdopendir.c: Likewise.
* sysdeps/posix/opendir.c: Likewise.
* sysdeps/unix/pt-fcntl.c: Likewise.
* include/fcntl.h (__libc_fcntl64, __fcntl64,
__fcntl64_nocancel_adjusted): New prototype.
(__fcntl_nocancel_adjusted): Remove prototype.
* io/Makefile (routines): Add fcntl64.
(CFLAGS-fcntl64.c): New rule.
* io/Versions [GLIBC_2.28] (fcntl64): New symbol.
[GLIBC_PRIVATE] (__libc_fcntl): Rename to __libc_fcntl64.
* io/fcntl.h (fcntl64): Add prototype and redirect if
__USE_FILE_OFFSET64 is defined.
* io/fcntl64.c: New file.
* manual/llio.text: Add a note for which commands fcntl acts a
cancellation point.
* nptl/Makefile (CFLAGS-fcntl64.c): New rule.
* sysdeps/mach/hurd/fcntl.c: Alias fcntl to fcntl64 symbols.
* sysdeps/mach/hurd/i386/libc.abilist [GLIBC_2.28] (fcntl, fcntl64):
New symbols.
* sysdeps/unix/sysv/linux/fcntl.c (__libc_fcntl): Fix F_GETLK64,
F_OFD_GETLK, F_SETLK64, F_SETLKW64, F_OFD_SETLK, and F_OFD_SETLKW for
non-LFS case.
* sysdeps/unix/sysv/linux/fcntl64.c: New file.
* sysdeps/unix/sysv/linux/fcntl_nocancel.c (__fcntl_nocancel): Rename
to __fcntl64_nocancel.
(__fcntl_nocancel_adjusted): Rename to __fcntl64_nocancel_adjusted.
* sysdeps/unix/sysv/linux/not-cancel.h (__fcntl_nocancel): Rename
to __fcntl64_nocancel.
* sysdeps/unix/sysv/linux/tst-ofdlocks.c: New file.
* sysdeps/unix/sysv/linux/tst-ofdlocks-compat.c: Likewise.
* sysdeps/unix/sysv/linux/Makefile (tests): Add tst-ofdlocks.
(tests-internal): Add tst-ofdlocks-compat.
* sysdeps/unix/sysv/linux/aarch64/libc.abilist [GLIBC_2.28]
(fcntl64): New symbol.
* sysdeps/unix/sysv/linux/alpha/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/ia64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist: Likewise.
* sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/arm/libc.abilist [GLIBC_2.28] (fcntl,
fcntl64): Likewise.
* sysdeps/unix/sysv/linux/hppa/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/i386/libc.abilis: Likewise.
* sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/microblaze/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/nios2/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sh/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist: Likewise.
Neither the <dlfcn.h> entry points, nor lazy symbol resolution, nor
initial shared library load-up, are cancellation points, so ld.so
should exclusively use I/O primitives that are not cancellable. We
currently achieve this by having the cancellation hooks compile as
no-ops when IS_IN(rtld); this patch changes to using exclusively
_nocancel primitives in the source code instead, which makes the
intent clearer and significantly reduces the amount of code compiled
under IS_IN(rtld) as well as IS_IN(libc) -- in particular,
elf/Makefile no longer thinks we require a copy of unwind.c in
rtld-libc.a. (The older mechanism is preserved as a backstop.)
The bulk of the change is splitting up the files that define the
_nocancel I/O functions, so they don't also define the variants that
*are* cancellation points; after which, the existing logic for picking
out the bits of libc that need to be recompiled as part of ld.so Just
Works. I did this for all of the _nocancel functions, not just the
ones used by ld.so, for consistency.
fcntl was a little tricky because it's only a cancellation point for
certain opcodes (F_SETLKW(64), which can block), and the existing
__fcntl_nocancel wasn't applying the FCNTL_ADJUST_CMD hook, which
strikes me as asking for trouble, especially as the only nontrivial
definition of FCNTL_ADJUST_CMD (for powerpc64) changes F_*LK* opcodes.
To fix this, fcntl_common moves to fcntl_nocancel.c along with
__fcntl_nocancel, and changes its name to the extern (but hidden)
symbol __fcntl_nocancel_adjusted, so that regular fcntl can continue
calling it. __fcntl_nocancel now applies FCNTL_ADJUST_CMD; so that
both both fcntl.c and fcntl_nocancel.c can see it, the only nontrivial
definition moves from sysdeps/u/s/l/powerpc/powerpc64/fcntl.c to
.../powerpc64/sysdep.h and becomes entirely a macro, instead of a macro
that calls an inline function.
The nptl version of libpthread also changes a little, because its
"compat-routines" formerly included files that defined all the
_nocancel functions it uses; instead of continuing to duplicate them,
I exported the relevant ones from libc.so as GLIBC_PRIVATE. Since the
Linux fcntl.c calls a function defined by fcntl_nocancel.c, it can no
longer be used from libpthread.so; instead, introduce a custom
forwarder, pt-fcntl.c, and export __libc_fcntl from libc.so as
GLIBC_PRIVATE. The nios2-linux ABI doesn't include a copy of vfork()
in libpthread, and it was handling that by manipulating
libpthread-routines in .../linux/nios2/Makefile; it is cleaner to do
what other such ports do, and have a pt-vfork.S that defines no symbols.
Right now, it appears that Hurd does not implement _nocancel I/O, so
sysdeps/generic/not-cancel.h will forward everything back to the
regular functions. This changed the names of some of the functions
that sysdeps/mach/hurd/dl-sysdep.c needs to interpose.
* elf/dl-load.c, elf/dl-misc.c, elf/dl-profile.c, elf/rtld.c
* sysdeps/unix/sysv/linux/dl-sysdep.c
Include not-cancel.h. Use __close_nocancel instead of __close,
__open64_nocancel instead of __open, __read_nocancel instead of
__libc_read, and __write_nocancel instead of __libc_write.
* csu/check_fds.c (check_one_fd)
* sysdeps/posix/fdopendir.c (__fdopendir)
* sysdeps/posix/opendir.c (__alloc_dir): Use __fcntl_nocancel
instead of __fcntl and/or __libc_fcntl.
* sysdeps/unix/sysv/linux/pthread_setname.c (pthread_setname_np)
* sysdeps/unix/sysv/linux/pthread_getname.c (pthread_getname_np)
* sysdeps/unix/sysv/linux/i386/smp.h (is_smp_system):
Use __open64_nocancel instead of __open_nocancel.
* sysdeps/unix/sysv/linux/not-cancel.h: Move all of the
hidden_proto declarations to the end and issue them if either
IS_IN(libc) or IS_IN(rtld).
* sysdeps/unix/sysv/linux/Makefile [subdir=io] (sysdep_routines):
Add close_nocancel, fcntl_nocancel, nanosleep_nocancel,
open_nocancel, open64_nocancel, openat_nocancel, pause_nocancel,
read_nocancel, waitpid_nocancel, write_nocancel.
* io/Versions [GLIBC_PRIVATE]: Add __libc_fcntl,
__fcntl_nocancel, __open64_nocancel, __write_nocancel.
* posix/Versions: Add __nanosleep_nocancel, __pause_nocancel.
* nptl/pt-fcntl.c: New file.
* nptl/Makefile (pthread-compat-wrappers): Remove fcntl.
(libpthread-routines): Add pt-fcntl.
* include/fcntl.h (__fcntl_nocancel_adjusted): New function.
(__libc_fcntl): Remove attribute_hidden.
* sysdeps/unix/sysv/linux/fcntl.c (__libc_fcntl): Call
__fcntl_nocancel_adjusted, not fcntl_common.
(__fcntl_nocancel): Move to new file fcntl_nocancel.c.
(fcntl_common): Rename to __fcntl_nocancel_adjusted; also move
to fcntl_nocancel.c.
* sysdeps/unix/sysv/linux/fcntl_nocancel.c: New file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/fcntl.c: Remove file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h:
Define FCNTL_ADJUST_CMD here, as a self-contained macro.
* sysdeps/unix/sysv/linux/close.c: Move __close_nocancel to...
* sysdeps/unix/sysv/linux/close_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/nanosleep.c: Move __nanosleep_nocancel to...
* sysdeps/unix/sysv/linux/nanosleep_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/open.c: Move __open_nocancel to...
* sysdeps/unix/sysv/linux/open_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/open64.c: Move __open64_nocancel to...
* sysdeps/unix/sysv/linux/open64_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/openat.c: Move __openat_nocancel to...
* sysdeps/unix/sysv/linux/openat_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/openat64.c: Move __openat64_nocancel to...
* sysdeps/unix/sysv/linux/openat64_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/pause.c: Move __pause_nocancel to...
* sysdeps/unix/sysv/linux/pause_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/read.c: Move __read_nocancel to...
* sysdeps/unix/sysv/linux/read_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/waitpid.c: Move __waitpid_nocancel to...
* sysdeps/unix/sysv/linux/waitpid_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/write.c: Move __write_nocancel to...
* sysdeps/unix/sysv/linux/write_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/nios2/Makefile: Don't override
libpthread-routines.
* sysdeps/unix/sysv/linux/nios2/pt-vfork.S: New file which
defines nothing.
* sysdeps/mach/hurd/dl-sysdep.c: Define __read instead of
__libc_read, and __write instead of __libc_write. Define
__open64 in addition to __open.
libpthread_nonshared.a is unused after this, so remove it from the
build.
There is no ABI impact because pthread_atfork was implemented using
__register_atfork in libc even before this change.
pthread_atfork has to be a weak alias because pthread_* names are not
reserved in libc.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
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.
An elided mutex don't fail destroy. Elision was disabled for the
test nptl/tst-mutex8 in nptl/Makefile. Thus we can run tests which
destroy a locked mutex.
As elision is only disabled for tst-mutex8, the variants
tst-mutex8-static, tst-mutexpi8 and tst-mutexpi8-static are still
failing if lock elision is enabled.
This patch adds a runtime check, if the checked type of mutex will
be elided. This check is using TUNABLE_GET_FULL to determine if
elision is enabled via the tunables framework.
The pthread_mutex_destroy tests are only run if we dont't assume an
elided mutex.
This way, we can run the whole glibc testsuite with or without enabled
lock elision.
ChangeLog:
* nptl/Makefile (tst-mutex8-ENV): Delete.
* nptl/tst-mutex8.c (check_type):
Add runtime check if mutex will be elided.
In commit cba595c350 and commit
f81ddabffd, ABI compatibility with
applications was broken by increasing the size of the on-stack
allocated __pthread_unwind_buf_t beyond the oringal size.
Applications only have the origianl space available for
__pthread_unwind_register, and __pthread_unwind_next to use,
any increase in the size of __pthread_unwind_buf_t causes these
functions to write beyond the original structure into other
on-stack variables leading to segmentation faults in common
applications like vlc. The only workaround is to version those
functions which operate on the old sized objects, but this must
happen in glibc 2.28.
Thank you to Andrew Senkevich, H.J. Lu, and Aurelien Jarno, for
submitting reports and tracking the issue down.
The commit reverts the above mentioned commits and testing on
x86_64 shows that the ABI compatibility is restored. A tst-cleanup1
regression test linked with an older glibc now passes when run
with the newly built glibc. Previously a tst-cleanup1 linked with
an older glibc would segfault when run with an affected glibc build.
Tested on x86_64 with no regressions.
Signed-off-by: Carlos O'Donell <carlos@redhat.com>
I verified that without the guard accounting change in commit
630f4cc3aa (Fix stack guard size
accounting) and RTLD_NOW for libgcc_s introduced by commit
f993b87540 (nptl: Open libgcc.so with
RTLD_NOW during pthread_cancel), the tst-minstack-cancel test fails on
an AVX-512F machine. tst-minstack-exit still passes, and either of
the mentioned commit by itself frees sufficient stack space to make
tst-minstack-cancel pass, too.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
GCC PR 83641 results in a miscompilation of libpthread, which
causes pthread_exit not to restore callee-saved registers before
running destructors for objects on the stack. This test detects
this situation:
info: unsigned int, direct pthread_exit call
tst-thread-exit-clobber.cc:80: numeric comparison failure
left: 4148288912 (0xf741dd90); from: value
right: 1600833940 (0x5f6ac994); from: magic_values.v2
info: double, direct pthread_exit call
info: unsigned int, indirect pthread_exit call
info: double, indirect pthread_exit call
error: 1 test failures
`make check' sometimes triggers a rebuild of librt.so using
nptl/Makefile, which ignores librt's dependence on libpthread. This
causes the build to blow up when we attempt to run the test suite on
RISC-V.
2018-01-06 Palmer Dabbelt <palmer@sifive.com>
* nptl/Makefile (/librt.so): Always depend on
"$(shared-thread-library)".
This patch consolidates the pthread_join and gnu extensions to avoid
code duplication. The function pthread_join, pthread_tryjoin_np, and
pthread_timedjoin_np are now based on pthread_timedjoin_ex.
It also fixes some inconsistencies on ESRCH, EINVAL, EDEADLK handling
(where each implementation differs from each other) and also on
clenup handler (which now always use a CAS).
Checked on i686-linux-gnu and x86_64-linux-gnu.
* nptl/pthreadP.h (__pthread_timedjoin_np): Define.
* nptl/pthread_join.c (pthread_join): Use __pthread_timedjoin_np.
* nptl/pthread_tryjoin.c (pthread_tryjoin): Likewise.
* nptl/pthread_timedjoin.c (cleanup): Use CAS on argument setting.
(pthread_timedjoin_np): Define internal symbol and common code from
pthread_join.
* sysdeps/unix/sysv/linux/i386/lowlevellock.h (__lll_timedwait_tid):
Remove superflous checks.
* sysdeps/unix/sysv/linux/x86_64/lowlevellock.h (__lll_timedwait_tid):
Likewise.
Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
All binaries use TLS and thus need a properly set up TCB, so we can
simply return its address directly, instead of forwarding to the
libpthread implementation from libc.
For versioned symbols, the dynamic linker checks that the soname matches
the name supplied by the link editor, so a compatibility symbol in
libpthread is needed.
To avoid linking against the libpthread function in all cases, we would
have to bump the symbol version of libpthread in libc.so and supply a
compat symbol. This commit does not do that because the function
implementation is so small, so the overhead by two active copies of the
same function might well be smaller than the increase in symbol table
size.
On x86, padding in struct __jmp_buf_tag is used for shadow stack pointer
to support shadow stack in Intel Control-flow Enforcemen Technology.
Since the cancel_jmp_buf array is passed to setjmp and longjmp by
casting it to pointer to struct __jmp_buf_tag, it should be as large
as struct __jmp_buf_tag. Otherwise when shadow stack is enabled,
setjmp and longjmp will write and read beyond cancel_jmp_buf when saving
and restoring shadow stack pointer.
This patch adds bits/types/__cancel_jmp_buf_tag.h to define struct
__cancel_jmp_buf_tag so that Linux/x86 can add saved_mask to
cancel_jmp_buf.
Tested natively on i386, x86_64 and x32. Tested hppa-linux-gnu with
build-many-glibcs.py.
[BZ #22563]
* bits/types/__cancel_jmp_buf_tag.h: New file.
* sysdeps/unix/sysv/linux/x86/bits/types/__cancel_jmp_buf_tag.h
* sysdeps/unix/sysv/linux/x86/pthreaddef.h: Likewise.
* sysdeps/unix/sysv/linux/x86/nptl/pthreadP.h: Likewise.
* nptl/Makefile (headers): Add
bits/types/__cancel_jmp_buf_tag.h.
* nptl/descr.h [NEED_SAVED_MASK_IN_CANCEL_JMP_BUF]
(pthread_unwind_buf): Add saved_mask to cancel_jmp_buf.
* sysdeps/nptl/pthread.h: Include
<bits/types/__cancel_jmp_buf_tag.h>.
(__pthread_unwind_buf_t): Use struct __cancel_jmp_buf_tag with
__cancel_jmp_buf.
* sysdeps/unix/sysv/linux/hppa/pthread.h: Likewise.
This patch adds several new tunables to control the behavior of
elision on supported platforms[1]. Since elision now depends
on tunables, we should always *compile* with elision enabled,
and leave the code disabled, but available for runtime
selection. This gives us *much* better compile-time testing of
the existing code to avoid bit-rot[2].
Tested on ppc, ppc64, ppc64le, s390x and x86_64.
[1] This part of the patch was initially proposed by
Paul Murphy but was "staled" because the framework have changed
since the patch was originally proposed:
https://patchwork.sourceware.org/patch/10342/
[2] This part of the patch was inititally proposed as a RFC by
Carlos O'Donnell. Make sense to me integrate this on the patch:
https://sourceware.org/ml/libc-alpha/2017-05/msg00335.html
* elf/dl-tunables.list: Add elision parameters.
* manual/tunables.texi: Add entries about elision tunable.
* sysdeps/unix/sysv/linux/powerpc/elision-conf.c:
Add callback functions to dynamically enable/disable elision.
Add multiple callbacks functions to set elision parameters.
Deleted __libc_enable_secure check.
* sysdeps/unix/sysv/linux/s390/elision-conf.c: Likewise.
* sysdeps/unix/sysv/linux/x86/elision-conf.c: Likewise.
* configure: Regenerated.
* configure.ac: Option enable_lock_elision was deleted.
* config.h.in: ENABLE_LOCK_ELISION flag was deleted.
* config.make.in: Remove references to enable_lock_elision.
* manual/install.texi: Elision configure option was removed.
* INSTALL: Regenerated to remove enable_lock_elision.
* nptl/Makefile:
Disable elision so it can verify error case for destroying a mutex.
* sysdeps/powerpc/nptl/elide.h:
Cleanup ENABLE_LOCK_ELISION check.
Deleted macros for the case when ENABLE_LOCK_ELISION was not defined.
* sysdeps/s390/configure: Regenerated.
* sysdeps/s390/configure.ac: Remove references to enable_lock_elision..
* nptl/tst-mutex8.c:
Deleted all #ifndef ENABLE_LOCK_ELISION from the test.
* sysdeps/powerpc/powerpc32/sysdep.h:
Deleted all ENABLE_LOCK_ELISION checks.
* sysdeps/powerpc/powerpc64/sysdep.h: Likewise.
* sysdeps/powerpc/sysdep.h: Likewise.
* sysdeps/s390/nptl/bits/pthreadtypes-arch.h: Likewise.
* sysdeps/unix/sysv/linux/powerpc/force-elision.h: Likewise.
* sysdeps/unix/sysv/linux/s390/elision-conf.h: Likewise.
* sysdeps/unix/sysv/linux/s390/force-elision.h: Likewise.
* sysdeps/unix/sysv/linux/s390/lowlevellock.h: Likewise.
* sysdeps/unix/sysv/linux/s390/Makefile: Remove references to
enable-lock-elision.
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.vnet.ibm.com>
Various subdirectories of glibc include Banner files to put some text
in the output of executing libc.so.6, under "Available extensions".
Some of those subdirectories (e.g. crypt) may originally have been
add-ons (and so optional, so a particular glibc build might or might
not have included them), but except for libidn they aren't now (or if
only included in some builds, in the case of soft-fp, the inclusion
depends on the architecture for which glibc is configured rather than
having any glibc configuration for which it's an optional feature),
and it doesn't seem useful for the libc.so.6 output to call out a few
features like that.
This patch removes the non-add-on Banner files, updating contrib.texi
where they noted contributions not otherwise mentioned there.
Tested for x86_64.
* crypt/Banner: Remove file.
* nptl/Banner: Likewise.
* resolv/Banner: Likewise.
* soft-fp/Banner: Likewise.
* nptl/Makefile ($(objpfx)banner.h): Remove rule.
($(objpfx)version.d): Remove dependency on banner.h.
($(objpfx)version.os): Likewise.
* nptl/version.c (banner): Do not include banner.h.
* manual/contrib.texi: Update entries for Richard Henderson, Jakub
Jelinek and BIND code.
65810f0ef0 fixed a robust mutex bug but
introduced BZ 21778: if the CAS used to try to acquire a lock fails, the
expected value is not updated, which breaks other cases in the loce
acquisition loop. The fix is to simply update the expected value with
the value returned by the CAS, which ensures that behavior is as if the
first case with the CAS never happened (if the CAS fails).
This is a regression introduced in the last release.
Tested on x86_64, i686, ppc64, ppc64le, s390x, aarch64, armv7hl.
Without this fix, the rwlock can fail to execute the explicit hand-over
in certain cases (e.g., empty critical sections that switch quickly between
read and write phases). This can then lead to errors in how __wrphase_futex
is accessed, which in turn can lead to deadlocks.
Single thread optimization is valid if at thread creation time the
optimization can be disabled. This is in principle true for all
stream objects that user code can access (and thus needs locking),
using the same internal list as fflush(0) uses. However in glibc
open_memstream is not on that list (BZ 21735) so the optimization
has to be disabled.
* libio/memstream.c (__open_memstream): Set _IO_FLAGS2_NEED_LOCK.
* libio/wmemstream.c (open_wmemstream): Likewise.
* nptl/tst-memstream.c: New.
The following tests depend on ENABLE_LOCK_ELISION, which is only
available on tests-internal.
- nptl/tst-mutex8
- nptl/tst-mutex8-static
- nptl/tst-mutexpi8
- nptl/tst-mutexpi8-static
* nptl/Makefile (tests): Move nptl/tst-mutex8, nptl/tst-mutex8-static,
nptl/tst-mutexpi8 and nptl/tst-mutexpi8-static to...
(tests-internal): ... here.
This patch consolidates the fsync Linux syscall generation on
sysdeps/unix/sysv/linux/fsync.c. It basically removes it from
architectures auto-generation list.
For arm it also removes the __errno_location call since fsync
is not called with SYSCALL_CANCEL with call arch-specific
INLINE_SYSCALL macro which in turn will call __set_errno macro
(and setting errno directly).
Checked on i686-linux-gnu, x86_64-linux-gnu, x86_64-linux-gnux32,
arch64-linux-gnu, arm-linux-gnueabihf, powerpc64le-linux-gnu,
sparc64-linux-gnu, and sparcv9-linux-gnu.
* misc/Makefile (CFLAGS-fsync.c): New flag.
* nptl/Makefile (CFLAGS-fsync.c): Likewise.
* sysdeps/unix/syscalls.list (fsync): Remove from auto-generation
syscall list.
* sysdeps/unix/sysv/linux/fsync.c: New file.
* sysdeps/unix/sysv/linux/arm/localplt.data [libpthread.so]
(__errno_location): Remove.
This patch consolidates the fdatasync Linux syscall generation on
sysdeps/unix/sysv/linux/fdatasync.c. It basically removes it from
architectures auto-generation list.
Checked on i686-linux-gnu, x86_64-linux-gnu, x86_64-linux-gnux32,
arch64-linux-gnu, arm-linux-gnueabihf, powerpc64le-linux-gnu,
sparc64-linux-gnu, and sparcv9-linux-gnu.
* misc/makefile (CFLAGS-datasync.c): New flag.
* nptl/makefile (CFLAGS-datasync.c): Likewise.
* sysdeps/unix/sysv/linux/syscalls.list (fdatasync): Remove from
auto-generation syscall list.
* sysdeps/unix/sysv/linux/fdatasync.c: New file.
This patch consolidates the msync Linux syscall generation on
sysdeps/unix/sysv/linux/msync.c. It basically removes it from
architectures auto-generation list.
Checked on i686-linux-gnu, x86_64-linux-gnu, x86_64-linux-gnux32,
arch64-linux-gnu, arm-linux-gnueabihf, powerpc64le-linux-gnu,
sparc64-linux-gnu, and sparcv9-linux-gnu.
* misc/Makefile (CFLAGS-msync.c): New rule.
* nptl/Makefile (CFLAGS-msync.c): Likewise.
* sysdeps/unix/syscalls.list: Remove msync from auto-generation list.
* sysdeps/unix/sysv/linux/msync.c: New file.
This patch consolidates the sigsuspend Linux syscall generation on
sysdeps/unix/sysv/linux/sigsuspend.c. It basically removes the alpha
assembly version which call the old sigsusped interface using only
the first doubleword from sigset. Current minimum supported kernel
on alpha (3.2) enforces rt_sigsuspend on the architecture
(__ARCH_WANT_SYS_RT_SIGSUSPEND option on kernel), so it is possible
to use the default implementation.
Checked on i686-linux-gnu, x86_64-linux-gnu, x86_64-linux-gnux32,
arch64-linux-gnu, arm-linux-gnueabihf, powerpc64le-linux-gnu,
sparc64-linux-gnu, and sparcv9-linux-gnu.
* sysdeps/unix/sysv/linux/alpha/sigsuspend.S: Remove file.
* sysdeps/unix/sysv/linux/sigsuspend.c: Simplify include list.
* nptl/Makefile (CFLAGS-sigsuspend.c): New rule.
* sysdeps/unix/sysv/linux/sparc/sparc64/Makefile
(CFLAGS-sigsuspend.c): Remove rule.
This patch consolidates the nanosleep Linux syscall generation on
sysdeps/unix/sysv/linux/nanosleep.c. It basically removes it from
architectures auto-generation list.
Checked on i686-linux-gnu, x86_64-linux-gnu, x86_64-linux-gnux32,
arch64-linux-gnu, arm-linux-gnueabihf, powerpc64le-linux-gnu,
sparc64-linux-gnu, and sparcv9-linux-gnu.
* nptl/Makefile (CFLAGS-nanosleep.c): New rule.
* posix/Makefile (CFLAGS-nanosleep.c): Likewise.
* sysdeps/unix/sysv/linux/nanosleep.c: New file.
* sysdeps/unix/sysv/linux/syscalls.list: Remove nanosleep from
auto-generated list.
This patch adds a new build module called 'testsuite'.
IS_IN (testsuite) implies _ISOMAC, as do IS_IN_build and __cplusplus
(which means several ad-hoc tests for __cplusplus can go away).
libc-symbols.h now suppresses almost all of *itself* when _ISOMAC is
defined; in particular, _ISOMAC mode does not get config.h
automatically anymore.
There are still quite a few tests that need to see internal gunk of
one variety or another. For them, we now have 'tests-internal' and
'test-internal-extras'; files in this category will still be compiled
with MODULE_NAME=nonlib, and everything proceeds as it always has.
The bulk of this patch is moving tests from 'tests' to
'tests-internal'. There is also 'tests-static-internal', which has
the same effect on files in 'tests-static', and 'modules-names-tests',
which has the *inverse* effect on files in 'modules-names' (it's
inverted because most of the things in modules-names are *not* tests).
For both of these, the file must appear in *both* the new variable and
the old one.
There is also now a special case for when libc-symbols.h is included
without MODULE_NAME being defined at all. (This happens during the
creation of libc-modules.h, and also when preprocessing Versions
files.) When this happens, IS_IN is set to be always false and
_ISOMAC is *not* defined, which was the status quo, but now it's
explicit.
The remaining changes to C source files in this patch seemed likely to
cause problems in the absence of the main change. They should be
relatively self-explanatory. In a few cases I duplicated a definition
from an internal header rather than move the test to tests-internal;
this was a judgement call each time and I'm happy to change those
however reviewers feel is more appropriate.
* Makerules: New subdir configuration variables 'tests-internal'
and 'test-internal-extras'. Test files in these categories will
still be compiled with MODULE_NAME=nonlib. Test files in the
existing categories (tests, xtests, test-srcs, test-extras) are
now compiled with MODULE_NAME=testsuite.
New subdir configuration variable 'modules-names-tests'. Files
which are in both 'modules-names' and 'modules-names-tests' will
be compiled with MODULE_NAME=testsuite instead of
MODULE_NAME=extramodules.
(gen-as-const-headers): Move to tests-internal.
(do-tests-clean, common-mostlyclean): Support tests-internal.
* Makeconfig (built-modules): Add testsuite.
* Makefile: Change libof-check-installed-headers-c and
libof-check-installed-headers-cxx to 'testsuite'.
* Rules: Likewise. Support tests-internal.
* benchtests/strcoll-inputs/filelist#en_US.UTF-8:
Remove extra-modules.mk.
* config.h.in: Don't check for __OPTIMIZE__ or __FAST_MATH__ here.
* include/libc-symbols.h: Move definitions of _GNU_SOURCE,
PASTE_NAME, PASTE_NAME1, IN_MODULE, IS_IN, and IS_IN_LIB to the
very top of the file and rationalize their order.
If MODULE_NAME is not defined at all, define IS_IN to always be
false, and don't define _ISOMAC.
If any of IS_IN (testsuite), IS_IN_build, or __cplusplus are
true, define _ISOMAC and suppress everything else in this file,
starting with the inclusion of config.h.
Do check for inappropriate definitions of __OPTIMIZE__ and
__FAST_MATH__ here, but only if _ISOMAC is not defined.
Correct some out-of-date commentary.
* include/math.h: If _ISOMAC is defined, undefine NO_LONG_DOUBLE
and _Mlong_double_ before including math.h.
* include/string.h: If _ISOMAC is defined, don't expose
_STRING_ARCH_unaligned. Move a comment to a more appropriate
location.
* include/errno.h, include/stdio.h, include/stdlib.h, include/string.h
* include/time.h, include/unistd.h, include/wchar.h: No need to
check __cplusplus nor use __BEGIN_DECLS/__END_DECLS.
* misc/sys/cdefs.h (__NTHNL): New macro.
* sysdeps/m68k/m680x0/fpu/bits/mathinline.h
(__m81_defun): Use __NTHNL to avoid errors with GCC 6.
* elf/tst-env-setuid-tunables.c: Include config.h with _LIBC
defined, for HAVE_TUNABLES.
* inet/tst-checks-posix.c: No need to define _ISOMAC.
* intl/tst-gettext2.c: Provide own definition of N_.
* math/test-signgam-finite-c99.c: No need to define _ISOMAC.
* math/test-signgam-main.c: No need to define _ISOMAC.
* stdlib/tst-strtod.c: Convert to test-driver. Split locale_test to...
* stdlib/tst-strtod1i.c: ...this new file.
* stdlib/tst-strtod5.c: Convert to test-driver and add copyright notice.
Split tests of __strtod_internal to...
* stdlib/tst-strtod5i.c: ...this new file.
* string/test-string.h: Include stdint.h. Duplicate definition of
inhibit_loop_to_libcall here (from libc-symbols.h).
* string/test-strstr.c: Provide dummy definition of
libc_hidden_builtin_def when including strstr.c.
* sysdeps/ia64/fpu/libm-symbols.h: Suppress entire file in _ISOMAC
mode; no need to test __STRICT_ANSI__ nor __cplusplus as well.
* 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.
* elf/Makefile: Move tst-ptrguard1-static, tst-stackguard1-static,
tst-tls1-static, tst-tls2-static, tst-tls3-static, loadtest,
unload, unload2, circleload1, neededtest, neededtest2,
neededtest3, neededtest4, tst-tls1, tst-tls2, tst-tls3,
tst-tls6, tst-tls7, tst-tls8, tst-dlmopen2, tst-ptrguard1,
tst-stackguard1, tst-_dl_addr_inside_object, and all of the
ifunc tests to tests-internal.
Don't add $(modules-names) to test-extras.
* inet/Makefile: Move tst-inet6_scopeid_pton to tests-internal.
Add tst-deadline to tests-static-internal.
* malloc/Makefile: Move tst-mallocstate and tst-scratch_buffer to
tests-internal.
* misc/Makefile: Move tst-atomic and tst-atomic-long to tests-internal.
* nptl/Makefile: Move tst-typesizes, tst-rwlock19, tst-sem11,
tst-sem12, tst-sem13, tst-barrier5, tst-signal7, tst-tls3,
tst-tls3-malloc, tst-tls5, tst-stackguard1, tst-sem11-static,
tst-sem12-static, and tst-stackguard1-static to tests-internal.
Link tests-internal with libpthread also.
Don't add $(modules-names) to test-extras.
* nss/Makefile: Move tst-field to tests-internal.
* posix/Makefile: Move bug-regex5, bug-regex20, bug-regex33,
tst-rfc3484, tst-rfc3484-2, and tst-rfc3484-3 to tests-internal.
* stdlib/Makefile: Move tst-strtod1i, tst-strtod3, tst-strtod4,
tst-strtod5i, tst-tls-atexit, and tst-tls-atexit-nodelete to
tests-internal.
* sunrpc/Makefile: Move tst-svc_register to tests-internal.
* sysdeps/powerpc/Makefile: Move test-get_hwcap and
test-get_hwcap-static to tests-internal.
* sysdeps/unix/sysv/linux/Makefile: Move tst-setgetname to
tests-internal.
* sysdeps/x86_64/fpu/Makefile: Add all libmvec test modules to
modules-names-tests.
This patch consolidates the write Linux syscall implementation on
sysdeps/unix/sysv/linux/write.c.
Checked on i686-linux-gnu, x86_64-linux-gnu, x86_64-linux-gnux32,
arch64-linux-gnu, arm-linux-gnueabihf, and powerpc64le-linux-gnu.
* include/unistd.h (write): Add hidden proto.
* io/Makefile (CFLAGS-write.c): New rule.
* nptl/Makefile (CFLAGS-write.c): Likewise.
* sysdeps/unix/sysv/linux/write.c: New file.
This patch consolidates the read Linux syscall implementation on
sysdeps/unix/sysv/linux/read.c. This leads to a different frame
pointer creation on some architectures:
* It fixes BZ#21428 on aarch64, since now the returned address
for the read syscall can be correctly found out by
backtrace_symbols.
* It makes tst-backtrace{5,6} fails on powerpc due an issue on
its custom backtrace implementation. It is fixed on subsequent
patch from this set.
Checked on i686-linux-gnu, x86_64-linux-gnu, x86_64-linux-gnux32,
arch64-linux-gnu, arm-linux-gnueabihf, and powerpc64le-linux-gnu.
[BZ #21428]
* include/unistd.h (read): Add hidden proto.
* io/Makefile (CFLAGS-read.c): New rule.
* nptl/Makefile (CFLAGS-read.c): New rule.
* sysdeps/unix/sysv/linux/read.c: New file.
This patch consolidates the close Linux syscall generation on
sysdeps/unix/sysv/linux/close.c.
Checked on i686-linux-gnu, x86_64-linux-gnu, x86_64-linux-gnux32,
arch64-linux-gnu, arm-linux-gnueabihf, and powerpc64le-linux-gnu.
* nptl/Makefile (CFLAGS-close.c): New flag.
* sysdeps/unix/sysv/linux/close.c: New file.
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
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.
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.
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.
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.
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
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.
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.
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.)
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.
This reverts commit 62ce266b0b.
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.
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 manually tested on both
the gdb CLI and Eclipse CDT.
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 it 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 a native build and a cross build using a Beaglebone
Black, with the build system's filesystem shared with the board through NFS.
Finally, I've written a README that explains all this and more.
Hopefully this should be good to go in now. Thanks.
ChangeLog:
2016-07-04 Martin Galvan <martin.galvan@tallertechnologies.com>
* Makeconfig (build-hardcoded-path-in-tests): Set to 'yes' for shared builds
if tests-need-hardcoded-path is defined.
(all-subdirs): Add pretty-printers.
* Makerules ($(py-const)): New rule.
* Rules (others): Add $(py-const), if defined.
* nptl/Makefile (gen-py-const-headers): Define.
* nptl/nptl-printers.py: New file.
* nptl/nptl_lock_constants.pysym: Likewise.
* pretty-printers/Makefile: Likewise.
* pretty-printers/README: Likewise.
* pretty-printers/test-condvar-attributes.c: Likewise.
* pretty-printers/test-condvar-attributes.p: Likewise.
* pretty-printers/test-condvar-printer.c: Likewise.
* pretty-printers/test-condvar-printer.py: Likewise.
* pretty-printers/test-mutex-attributes.c: Likewise.
* pretty-printers/test-mutex-attributes.py: Likewise.
* pretty-printers/test-mutex-printer.c: Likewise.
* pretty-printers/test-mutex-printer.py: Likewise.
* pretty-printers/test-rwlock-attributes.c: Likewise.
* pretty-printers/test-rwlock-attributes.py: Likewise.
* pretty-printers/test-rwlock-printer.c: Likewise.
* pretty-printers/test-rwlock-printer.py: Likewise.
* pretty-printers/test_common.py: Likewise.
* scripts/gen-py-const.awk: Likewise.
tst-cleanupx4 is linked with tst-cleanupx4.o and tst-cleanup4aux.o.
Since tst-cleanupx4.o is compiled from tst-cleanup4.c with -fexceptions,
tst-cleanup4aux.c should also be compiled with -fexceptions.
Tested on x86-64 and i686.
[BZ #18645]
* nptl/Makefile (extra-test-objs): Add tst-cleanupx4aux.o.
(test-extras): Add tst-cleanupx4aux.
(CFLAGS-tst-cleanupx4aux.c): New. Set to -fexceptions.
($(objpfx)tst-cleanupx4): Replace tst-cleanup4aux.o with
tst-cleanupx4aux.o.
* nptl/tst-cleanupx4aux.c: New file.
This patch adds cancellation tests for both sendmmsg and recvmmsg
syscalls. Since for some system configuration (x86_64/i686 on
older kernels and non-Linux platforms), the tests are added as
two independent that report as unsupported if the syscall is not
presented.
Both new tests uses the already tst-cancel4.c code, which as moved
to a common tst-cancel4-common{.c,h} files.
Tested on x86_64 and i686.
* nptl/Makefile (test): Add tst-cancel4_1 and tst-cancel4_2.
* nptl/tst-cancel4-common.c: New file.
* nptl/tst-cancel4-common.h: Likewise.
* nptl/tst-cancel4.c: Move common definitions to
tst-cancel4-common.{c,h} file.
* nptl/tst-cancel4_1.c: New test.
* nptl/tst-cancel4_2.c: New test.
After some discussion in libc-alpha about this POSIX compliance fix, I see
that GLIBC should indeed revert back to previous definition of msghdr and
cmsghdr and implementation of sendmsg, recvmsg, sendmmsg, recvmmsg due some
reasons:
* The possible issue where the syscalls wrapper add the compatibility
layer is quite limited in scope and range. And kernel current
also add some limits to the values on the internal msghdr and
cmsghdr fields:
- msghdr::msg_iovlen larger than UIO_MAXIOV (1024) returns
EMSGSIZE.
- msghdr::msg_controllen larger than INT_MAX returns ENOBUFS.
* There is a small performance hit for recvmsg/sendmsg/recmmsg which
is neglectable, but it is a big hit for sendmmsg since now instead
of calling the syscall for the packed structure, GLIBC is calling
multiple sendmsg. This defeat the very existence of the syscall.
* It currently breaks libsanitizer build on GCC [1] (I fixed on compiler-rt).
However the fix is incomplete because it does add any runtime check
since libsanitizer currently does not have any facility to intercept
symbols with multiple version [2].
This, along with incorret dlsym/dlvsym return for versioned symbol due
another bug [3], makes hard to interpose versioned symbols.
Also, current approach of fixing GCC PR#71445 leads to half-baked
solutions without versioned symbol interposing.
This patch basically reverts commits 2f0dc39029, 222c2d7f43,
af7f7c7ec8. I decided to not revert abf29edd4a (Adjust
kernel-features.h defaults for recvmsg and sendmsg) mainly because it
does not really address the POSIX compliance original issue and also
adds some cleanups.
Tested on x86, i386, s390, s390x, aarch64, and powerpc64le.
[1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71445
[2] https://github.com/google/sanitizers/issues/628
[3] https://sourceware.org/bugzilla/show_bug.cgi?id=14932
* conform/data/sys/socket.h-data (msghdr.msg_iovlen): Add xfail-.
(msghdr.msg_controllen): Likewise.
(cmsghdr.cmsg_len): Likewise.
* nptl/Makefile (libpthread-routines): Remove ptw-oldrecvmsg and
ptw-oldsendmsg.
(CFLAGS-oldrecvmsg.c): Remove rule.
(CFLAGS-oldsendmsg.c): Likewise.
(CFLAGS-recvmsg.c): Add rule.
(CFLAGS-sendmsg.c): Likewise.
* sysdeps/unix/sysv/linux/Makefile (sysdep_routines): Remove
oldrecvmsg, oldsendmsg, oldrecvmmsg, oldsendmmsg.
(CFLAGS-recvmsg.c): Remove rule.
(CFLAGS-sendmsg.c): Likewise.
(CFLAGS-oldrecvmsg.c): Likewise.
(CFLAGS-oldsendmsg.c): Likewise.
(CFLAGS-recvmmsg.c): Likewise.
* sysdeps/unix/sysv/linux/bits/socket.h (msghdr.msg_iovlen): Revert
to kernel defined interfaces.
(msghdr.msg_controllen): Likewise.
(cmsghdr.cmsg_len): Likewise.
(msghdr.__glibc_reserved1): Remove member.
(msghdr.__glibc_reserved2): Likewise.
(cmsghdr.__glibc_reserved1): Likewise.
* sysdeps/unix/sysv/linux/oldrecvmmsg.c: Remove file.
* sysdeps/unix/sysv/linux/oldrecvmsg.c: Likewise.
* sysdeps/unix/sysv/linux/oldsendmmsg.c: Likewise.
* sysdeps/unix/sysv/linux/oldsendmsg.c: Likewise.
* sysdeps/unix/sysv/linux/recvmmsg.c: Revert back to previous
version.
* sysdeps/unix/sysv/linux/recvmsg.c: Likewise.
* sysdeps/unix/sysv/linux/sendmmsg.c: Likewise.
* sysdeps/unix/sysv/linux/sendmsg.c: Likewise.
* sysdeps/unix/sysv/linux/aarch64/Versions [libc] (GLIBC_2.24):
Remove recvmsg and sendmsg.
* sysdeps/unix/sysv/linux/alpha/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/hppa/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/i386/Versions [libc] (GLIBC_2.24): Likewise.
* sysdeps/unix/sysv/linux/m68k/Versions [libc] (GLIBC_2.24): Likewise.
* sysdeps/unix/sysv/linux/microblaze/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n32/Versions
[libc] (GLIBC_2.24): Likewise.
* sysdeps/unix/sysv/linux/nios2/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/powerpc/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/Versions
[libc] (GLIBC_2.24): Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/sh/Versions [libc] (GLIBC_2.24): Likewise.
* sysdeps/unix/sysv/linux/sparc/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/tile/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/x86_64/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/Versions: Remove file
* sysdeps/unix/sysv/linux/x86_64/64/Versions: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/Versions: Likewise.
* sysdeps/unix/sysv/linux/aarch64/libc.abilist: Remove new 2.24
version for {recv,send,recm,sendm}msg.
* sysdeps/unix/sysv/linux/alpha/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/arm/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/hppa/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/i386/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/ia64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/microblaze/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/nios2/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sh/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/tile/tilepro/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist: Likewise.
This patch fixes wrong/missing bits from the Fix {recv,send}{m}msg
standard compliance (BZ#16919) patches:
* nptl/Makefile sets CFLAGS-oldrecvfrom.c, but there's no such file as
oldrecvfrom.c. It should be oldsendmsg.c as defined by ChangeLog.
* sysdeps/unix/sysv/linux/hppa/Versions and
sysdeps/unix/sysv/linux/i386/Versions list a symbol recvms instead of
recvmsg at version GLIBC_2.24.
* nptl/Makefile (CFLAGS-oldrecvfrom.c): Remove rule.
(CFLAGS-oldsendmsg.c): Add rule.
* sysdeps/unix/sysv/linux/hppa/Versions [libc] (GLIBC_2.24):
Correct recvmsg symbol name.
* sysdeps/unix/sysv/linux/i386/Versions [libc] (GLIBC_2.24):
Likewise.
Error checking mutexes are not supposed to be subject to lock elision.
That would defeat the error checking nature of the mutex because lock
elision doesn't record ownership.
The previous barrier implementation did not fulfill the POSIX requirements
for when a barrier can be destroyed. Specifically, it was possible that
threads that haven't noticed yet that their round is complete still access
the barrier's memory, and that those accesses can happen after the barrier
has been legally destroyed.
The new algorithm does not have this issue, and it avoids using a lock
internally.
NPTL has tests that initializers work with various -std= options. Now
that we can rely on -std=gnu11 and -std=c11 being available, this
patch adds versions of those tests for those options.
Tested for x86_64 and x86 (testsuite).
* nptl/tst-initializers1-c11.c: New file.
* nptl/tst-initializers1-gnu11.c: Likewise.
* nptl/Makefile (tests): Add these new tests.
(CFLAGS-tst-initializers1-c11.c): New variable.
(CFLAGS-tst-initializers1-gnu11.c): Likewise.
sysdeps/nptl/configure.ac tests for forced unwind support and the C
cleanup attribute, giving errors if either is unsupported. It does
nothing beyond running those two tests.
Both the attribute, and _Unwind_GetCFA which is used in the forced
unwind test, were added in GCC 3.3. Thus these tests are long
obsolete, and this patch removes the configure fragment running them,
along with associated conditionals.
Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).
* sysdeps/nptl/configure.ac: Remove file.
* sysdeps/nptl/configure: Remove generated file.
* configure.ac (libc_cv_forced_unwind): Do not substitute.
* configure: Regenerated.
* config.h.in (HAVE_FORCED_UNWIND): Remove #undef.
* config.make.in (have-forced-unwind): Remove variable.
* nptl/Makefile [$(have-forced-unwind) = yes]: Make code
unconditional.
* nptl/descr.h [HAVE_FORCED_UNWIND]: Likewise.
* nptl/unwind.c [HAVE_FORCED_UNWIND]: Likewise.
(__pthread_unwind) [!HAVE_FORCED_UNWIND]: Remove conditional code.
* nptl/version.c [HAVE_FORCED_UNWIND]: Make code unconditional.
* sysdeps/nptl/Makefile [$(have-forced-unwind) = yes]: Make code
unconditional.
This patch pthread cancellation tests to check for failures cases
wherer the syscall cancel wrapper should both set the error and
the errno values.
Tested on i686, x86_64, x32, powerpc64le, and aarch64.
* nptl/Makefile (tests): Add tst-cancel26.c and tst-cancel27.c.
* nptl/tst-cancel26.c: New file.
* nptl/tst-cancel27.c: Likewise.
The recently introduced TLS variables in the thread-local destructor
implementation (__cxa_thread_atexit_impl) used the default GD access
model, resulting in a call to __tls_get_addr. This causes a deadlock
with recent changes to the way TLS is initialized because DTV
allocations are delayed and hence despite knowing the offset to the
variable inside its TLS block, the thread has to take the global rtld
lock to safely update the TLS offset.
This causes deadlocks when a thread is instantiated and joined inside
a destructor of a dlopen'd DSO. The correct long term fix is to
somehow not take the lock, but that will need a lot deeper change set
to alter the way in which the big rtld lock is used.
Instead, this patch just eliminates the call to __tls_get_addr for the
thread-local variables inside libc.so, libpthread.so and rtld by
building all of their units with -mtls-model=initial-exec.
There were concerns that the static storage for TLS is limited and
hence we should not be using it. Additionally, dynamically loaded
modules may result in libc.so looking for this static storage pretty
late in static binaries. Both concerns are valid when using TLSDESC
since that is where one may attempt to allocate a TLS block from
static storage for even those variables that are not IE. They're not
very strong arguments for the traditional TLS model though, since it
assumes that the static storage would be used sparingly and definitely
not by default. Hence, for now this would only theoretically affect
ARM architectures.
The impact is hence limited to statically linked binaries that dlopen
modules that in turn load libc.so, all that on arm hardware. It seems
like a small enough impact to justify fixing the larger problem that
currently affects everything everywhere.
This still does not solve the original problem completely. That is,
it is still possible to deadlock on the big rtld lock with a small
tweak to the test case attached to this patch. That problem is
however not a regression in 2.22 and hence could be tackled as a
separate project. The test case is picked up as is from Alex's patch.
This change has been tested to verify that it does not cause any
issues on x86_64.
ChangeLog:
[BZ #18457]
* nptl/Makefile (tests): New test case tst-join7.
(modules-names): New test case module tst-join7mod.
* nptl/tst-join7.c: New file.
* nptl/tst-join7mod.c: New file.
* Makeconfig (tls-model): Pass -ftls-model=initial-exec for
all translation units in libc.so, libpthread.so and rtld.
and also powerpc64 and powerpc64le. See the discussion in the thread
below for details. This change reverts the problematic bits leaving
the added test in place and marking XFAIL in anticipation of fixing
the bug in the near future.
https://sourceware.org/ml/libc-alpha/2015-07/msg00141.html
[BZ #18435]
* nptl/pthreadP.h (pthread_cleanup_push, pthread_cleanup_pop):
Revert commit ed225df3ad.
* nptl/Makefile (test-xfail-tst-once5): Define.
the initialization routine to exit by throwing an exception.
Such an execution, termed exceptional, requires call_once to
propagate the exception to its caller. A program may contain
any number of exceptional executions but only one returning
execution (which, if it exists, must be the last execution
with the same once flag).
On POSIX systems such as Linux, std::call_once is implemented
in terms of pthread_once. However, as discussed in libstdc++
bug 66146 - "call_once not C++11-compliant on ppc64le," GLIBC's
pthread_once hangs when the initialization function exits by
throwing an exception on at least arm and ppc64 (though
apparently not on x86_64). This effectively prevents call_once
from conforming to the C++ requirements since there doesn't
appear to be a thread-safe way to work around this problem in
libstdc++.
This patch changes pthread_once to handle gracefully init
functions that exit by throwing exceptions. It was successfully
tested on ppc64, ppc64le, and x86_64.
[BZ #18435]
* nptl/Makefile: Add tst-once5.cc.
* nptl/pthreadP.h (pthread_cleanup_push, pthread_cleanup_pop):
Remove macro redefinitions.
* nptl/tst-once5.cc: New test.
In commit 02657da2cf, .interp section
was removed from libpthread.so. This led to an error:
$ /lib64/libpthread.so.0
Native POSIX Threads Library by Ulrich Drepper et al
Copyright (C) 2015 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.
There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE.
Forced unwind support included.
Segmentation fault
(gdb) bt
#0 0x00000000000055a6 in _exit@plt ()
Unfortunately, there is no way to add a regression test for the bug
because .interp specifies the path to dynamic linker of the target
system.
[BZ #18479]
* nptl/pt-interp.c: New file.
* nptl/Makefile (libpthread-routines, libpthread-shared-only-routines):
Add pt-interp.
[$(build-shared) = yes] ($(objpfx)pt-interp.os): Depend on
$(common-objpfx)runtime-linker.h.
This adds wake-ups that would be missing if assuming that for a
non-writer-preferring rwlock, if one thread has acquired a rdlock and
does not release it, another thread will eventually acquire a rdlock too
despite concurrent write lock acquisition attempts. BZ 14958 is about
supporting this assumption. Strictly speaking, this isn't a valid
test case, but nonetheless worth supporting (see comment 7 of BZ 14958).
If we set up a rwlock to prefer writers (and disallow recursive rdlock
acquisitions), then readers will block for writers that are blocked to
acquire the lock (otherwise, readers could constantly enter and exit,
and the writer would never get the lock). However, the existing
implementation did not wake such readers when the writer timed out.
This patch adds the missing wake-up.
There's no similar case for writers being blocked on readers.
This patch removes the socket.S implementation for all ports and replace
it by a C implementation using socketcall. For ports that implement
the syscall directly, there is no change.
The patch idea is to simplify the socket function implementation that
uses the socketcall to be based on C implemetation instead of a pseudo
assembly implementation with arch specific parts. The patch then remove
the assembly implementatation for the ports which uses socketcall
(i386, microblaze, mips, powerpc, sparc, m68k, s390 and sh).
I have cross-build GLIBC for afore-mentioned ports and tested on both
i386 and ppc32 without regressions.
pthread_mutexattr_settype adds PTHREAD_MUTEX_NO_ELISION_NP to kind,
which is an internal flag that pthread_mutexattr_gettype shouldn't
expose, since pthread_mutexattr_settype wouldn't accept it.
This commit fixes semaphore destruction by either using 64b atomic
operations (where available), or by using two separate fields when only
32b atomic operations are available. In the latter case, we keep a
conservative estimate of whether there are any waiting threads in one
bit of the field that counts the number of available tokens, thus
allowing sem_post to atomically both add a token and determine whether
it needs to call futex_wake.
See:
https://sourceware.org/ml/libc-alpha/2014-12/msg00155.html
This patch changes _dl_allocate_tls_init to resize DTV if the current DTV
isn't big enough. Tested on X86-64, x32 and ia32.
[BZ #13862]
* elf/dl-tls.c: Include <atomic.h>.
(oom): Remove #ifdef SHARED/#endif.
(_dl_static_dtv, _dl_initial_dtv): Moved before ...
(_dl_resize_dtv): This. Extracted from _dl_update_slotinfo.
(_dl_allocate_tls_init): Resize DTV if the current DTV isn't
big enough.
(_dl_update_slotinfo): Call _dl_resize_dtv to resize DTV.
* nptl/Makefile (tests): Add tst-stack4.
(modules-names): Add tst-stack4mod.
($(objpfx)tst-stack4): New.
(tst-stack4mod.sos): Likewise.
($(objpfx)tst-stack4.out): Likewise.
($(tst-stack4mod.sos)): Likewise.
(clean): Likewise.
* nptl/tst-stack4.c: New file.
* nptl/tst-stack4mod.c: Likewise.
pthread_atfork is already built in an extra-libs context, which gives
it NOT_IN_libc in its CPPFLAGS. Adding the same definition to CFLAGS
is pointless.
Verified that the code is unchanged on x86_64.
If a call to the set*id functions fails in a multi-threaded program,
the abort introduced in commit 13f7fe35ae
was triggered.
We address by checking that all calls to set*id on all threads give
the same result, and only abort if we see success followed by failure
(or vice versa).
