Szabolcs Nagy [Thu, 30 Jan 2020 10:40:01 +0000 (10:40 +0000)]
Add NEWS entry about 64-bit time_t syscall use on 32-bit targets
This internal change ideally should not affect the public API or ABI,
but there is a widespread use of seccomp sandboxes, even on 32-bit
targets, that don't handle new Linux syscall usage well, so it's
worth mentioning in the NEWS.
Florian Weimer [Thu, 30 Jan 2020 14:54:49 +0000 (15:54 +0100)]
nptl: Avoid using PTHREAD_MUTEX_DEFAULT in macro definition [BZ #25271]
Commit 1c3f9acf1f1f75faa7a28bf39af64afd ("nptl: Add struct_mutex.h")
replaced a zero constant with the identifier PTHREAD_MUTEX_DEFAULT
in the macro PTHREAD_MUTEX_INITIALIZER. However, that constant
is not available in ISO C11 mode:
In file included from /usr/include/bits/thread-shared-types.h:74,
from /usr/include/bits/pthreadtypes.h:23,
from /usr/include/pthread.h:26,
from bug25271.c:1:
bug25271.c:3:21: error: ‘PTHREAD_MUTEX_DEFAULT’ undeclared here (not in a function)
3 | pthread_mutex_t m = PTHREAD_MUTEX_INITIALIZER;
| ^~~~~~~~~~~~~~~~~~~~~~~~~
This commit change the constant to the equivalent
PTHREAD_MUTEX_TIMED_NP, which is in the POSIX extension namespace
and thus always available.
Joseph Myers [Fri, 24 Jan 2020 17:23:47 +0000 (17:23 +0000)]
Build raise with -fasynchronous-unwind-tables.
In testing glibc for Arm and MIPS, I see:
FAIL: misc/tst-sigcontext-get_pc
If this test - backtracing through a call to raise - is valid, then
raise needs to be built with -fasynchronous-unwind-tables (as the test
itself is) to have the required unwind information for that
backtracing to work. Adding that option, which this patch does,
causes the test for pass for Arm. For MIPS, the test still does not
pass (the backtrace has an address that is 2 bytes after the "address
in signal handler", for unknown reasons), although the patch allows a
longer backtrace to be produced.
Joseph Myers [Fri, 24 Jan 2020 17:23:07 +0000 (17:23 +0000)]
Fix locale/tst-locale-locpath cross-testing when sshd sets LANG.
The locale/tst-locale-locpath test unsets LANG, then runs a test with
test_wrapper_env and expects LANG to remain unset for that test. This
does not work for cross-testing with cross-test-ssh.sh when sshd (on
the system specified as an argument to cross-test-ssh.sh) is
configured to have a default LANG setting.
The general design used in cross testing, after commit 8540f6d2a74fe9d67440535ebbcfa252180a3172 ("Don't require test wrappers
to preserve environment variables, use more consistent environment.",
6 June 2014), is that environment settings required by tests should be
passed explicitly to $(test-wrapper-env). This patch changes
tst-locale-locpath.sh to pass an explicit LANG= rather than expecting
"unset LANG" to be in effect for the program run under
test_wrapper_env. Note that this does slightly change the environment
in which the test is run natively (empty LANG instead of unset LANG)
but that difference does not appear relevant to what it is trying to
test.
Tested for Arm that this fixes the failure seen for that test in
cross-testing.
Joseph Myers [Fri, 24 Jan 2020 17:22:13 +0000 (17:22 +0000)]
Fix elf/tst-rtld-preload cross-testing.
As noted in
<https://sourceware.org/ml/libc-alpha/2019-06/msg00824.html>,
elf/tst-rtld-preload fails when cross-testing because it attempts to
run the test wrapper with itself. Unfortunately, that thread never
resulted in a complete and correct patch for that test.
This patch addresses the issues with that test more thoroughly. The
test is changed not to use the wrapper twice, including updating the
message it prints about the command it runs to be more complete and
accurate after the change; the Makefile is changed not to pass the
redundant '$(test-wrapper)' argument.
Tested for Arm that this fixes the failure seen for that test in
cross-testing.
Joseph Myers [Thu, 23 Jan 2020 14:34:16 +0000 (14:34 +0000)]
Fix cross-testing of tst-ifunc-fault-* tests.
The tests elf/tst-ifunc-fault-bindnow and elf/tst-ifunc-fault-lazy
fail in cross-testing because they run the dynamic linker directly
without using the test wrapper. This patch fixes them to use the test
wrapper instead.
Tested that this fixes the failure of those two tests for powerpc
soft-float.
gitlog-to-changelog: Drop scripts in favour of gnulib version
The ChangeLog automation scripts were incorporated in gnulib as
vcs-to-changelog for a while now since other projects expressed the
desire to use and extend this script. In the interest of avoiding
duplication of code, drop the glibc version of gitlog-to-changelog and
use the gnulib one directly.
The only file that remains is vcstocl_quirks.py, which specifies
properties and quirks of the glibc project source code. This patch
also drops the shebang at the start of vcstocl_quirks.py since the
file is not intended to be directly executable.
Andreas Schwab [Mon, 20 Jan 2020 16:01:50 +0000 (17:01 +0100)]
Fix array overflow in backtrace on PowerPC (bug 25423)
When unwinding through a signal frame the backtrace function on PowerPC
didn't check array bounds when storing the frame address. Fixes commit d400dcac5e ("PowerPC: fix backtrace to handle signal trampolines").
Stefan Liebler [Mon, 20 Jan 2020 09:55:55 +0000 (10:55 +0100)]
Get rid of Werror=maybe-uninitialized in res_send.c.
The commit 446997ff1433d33452b81dfa9e626b8dccf101a4 introduced
this new usage of resplen. If build with gcc 9 -march>=z13 on s390x,
the following warning occurs:
res_send.c: In function ‘__res_context_send’:
res_send.c:539:6: error: ‘resplen’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
539 | if (resplen > HFIXEDSZ)
| ^
Therefore this patch adds a further DIAG_IGNORE_NEEDS_COMMENT in the
same way as it was previously done for usages of resplen or n.
See commit d1bc2cbbed9aea2017ef941f63c8786571da5b4f.
The translation project coordinator Benno Schulenberg suggested that
we could save space in our tarball by trimming the generated po files
by using msgattrib and dropping all untranslated, fuzzy and obsolete
messages. This patch updates the update-translations target to do
that. Testing indicates that the current po files reduce by over 65K
lines due to this trimming.
translations: Run msgmerge when downloading translations
The latest translations in the translationproject URL need to be
merged in using msgmerge for the po files to be correctly updated,
otherwise we may end up getting odd results, such as the previous
translations update. This patch adds another step to the
update-translations Makefile target which does a msgmerge of the
downloaded po file with libc.pot and then uses that as the final
result.
Matheus Castanho [Fri, 17 Jan 2020 14:44:54 +0000 (11:44 -0300)]
Fix maybe-uninitialized error on powerpc
The build has been failing on powerpc64le-linux-gnu with GCC 10
due to a maybe-uninitialized error:
../sysdeps/ieee754/dbl-64/mpa.c:875:6: error: ‘w.e’ may be used
uninitialized in this function [-Werror=maybe-uninitialized]
875 | EY -= EX;
| ^~
The warning is thrown because when __inv is called by __dvd *y is not
initialized and if t == 0 before calling __dbl_mp, EY will stay
uninitialized, as the function does not touch it in this case.
However, since t will be set to 1/t before calling __dbl_mp, t == 0 will
never happen, so we can instruct the compiler to ignore this case, which
suppresses the warning.
Tested on powerpc64le.
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
Florian Weimer [Fri, 17 Jan 2020 14:05:34 +0000 (15:05 +0100)]
Remove incorrect alloc_size attribute from pvalloc [BZ #25401]
pvalloc is guarantueed to round up the allocation size to the page
size, so applications can assume that the memory region is larger
than the passed-in argument. The alloc_size attribute cannot express
that.
The test case is based on a suggestion from Jakub Jelinek.
Fix tst-pkey.c pkey_alloc return checks and manual
This test was failing in some powerpc systems as it was not checking
for ENOSPC return.
As said on the Linux man-pages and can be observed by the implementation
at mm/mprotect.c in the Linux Kernel source. The syscall pkey_alloc can
return EINVAL or ENOSPC. ENOSPC will indicate either that all keys are
in use or that the kernel does not support pkeys.
Reviewed-by: Gabriel F. T. Gomes <gabriel@inconstante.net.br>
The update-translation target seems to have downloaded outdated
translations for these languages. Revert them and try to figure out
if this is a problem with the target or an error in translations.
Florian Weimer [Thu, 16 Jan 2020 15:53:58 +0000 (16:53 +0100)]
elf: Add elf/tst-dlopenfail-2 [BZ #25396]
Without CET, a jump into a newly loaded object through an overwritten
link map often does not crash, it just executes some random code.
CET detects this in some cases because the function pointer does not
point to the start of a function in the replacement shared object,
so there is no ENDBR instruction.
The new test uses a small shared object and the existing dangling
link map to trigger the bug.
Joseph Myers [Mon, 13 Jan 2020 16:32:57 +0000 (16:32 +0000)]
Update build-many-glibcs.py for GCC move to git.
This patch updates build-many-glibcs.py for the move of GCC to git,
teaching it to do the initial checkout from git, to replace an SVN
checkout with a git one if --replace-sources is used, and to get the
commit identifier from a git checkout after updating it.
Stefan Liebler [Mon, 13 Jan 2020 10:06:41 +0000 (11:06 +0100)]
Fix "elf: Add tst-ldconfig-ld_so_conf-update test" on 32bit.
This new test was introduced with recent commit 591236f1a33f11cc65ccf009d997071ba853e186.
If run on 32bit, it fails while renaming tst-ldconfig-ld-mod.so as there is no
/usr/lib64 directory. This patch is constructing the file name with help of
support_libdir_prefix.
Paul Eggert [Fri, 10 Jan 2020 07:00:25 +0000 (23:00 -0800)]
Update timezone/README
* timezone/version: New file, also taken from tzcode2018i.
* timezone/README: Reword so that people needn't paw through
old ChangeLog files to see which version we're using, a process
that is error-prone. Update an obsolescent URL.
Test ldconfig after /etc/ld.so.conf update and verify a running process
observes changes to /etc/ld.so.cache.
The test uses the test-in-container framework.
Zack Weinberg [Wed, 8 Jan 2020 20:23:12 +0000 (15:23 -0500)]
Revise NEWS description of changes to gettimeofday etc.
Mostly English grammar and style improvements. The bullet list is
reorganized a little for clarity. The details of exactly which
Linux-based ports still report system-wide time zone information
from gettimeofday has been removed, as this is not intended to be
something people should rely on.
Also clarify the deprecation of older SPARC ISAs, based on the fact
that “SPARC version 7” is actually the very first version of the SPARC
ISA (Sun Microsystems was very fond of letting the marketing
department pick version numbers).
We no longer write manual ChangeLog entries since they are
auto-generated at release time. Drop dependency of the `make dist`
target on the file and document the fact that the latest ChangeLog
entries can be read in the highest numbered ChangeLog.N file in
ChangeLog.old.
The ChangeLog.old/ChangeLog.20 file for 2.31 will thus be generated
just before tagging a release.
Reviewed-by: Paul Eggert <eggert@cs.ucla.edu> Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Zack Weinberg [Wed, 8 Jan 2020 19:28:23 +0000 (14:28 -0500)]
MIPS: Fix circular definition of __LDBL_MANT_DIG__ in ieee754.h
In commit aa706e13f4bfdf32a27c498902edf4f6006e433e,
sysdeps/mips/ieee754/ieee754.h was changed to use GCC’s predefined
macro __LDBL_MANT_DIG__, instead of including <float.h> and using
LDBL_MANT_DIG (and therefore polluting the user namespace with all of
the macros defined in float.h). In order to support compilers that
don’t provide __LDBL_MANT_DIG__, there is a fallback #if block which
was supposed to include <float.h> and then define __LDBL_MANT_DIG__ to
LDBL_MANT_DIG. However, at some point during the development of the
patch, a typo was introduced, causing the fallback block to define
__LDBL_MANT_DIG__ to expand to __LDBL_MANT_DIG__.
Add another newline when the number of files differing is too large.
This is typical for across-the-board changes such as the copyright
year update that happened recently.
Samuel Thibault [Sat, 4 Jan 2020 18:37:53 +0000 (19:37 +0100)]
htl: Add __errno_location and __h_errno_location
As explained on
https://sourceware.org/ml/libc-alpha/2020-01/msg00049.html
the presence of __errno_location in libpthread.so on GNU/Linux makes
libpthread getting linked in for libstdc++. This aligns on that behavior, to
avoid issues that only GNU/Hurd would get.
Samuel Thibault [Sat, 4 Jan 2020 17:53:23 +0000 (18:53 +0100)]
htl: Move pthread_atfork to libc_nonshared.a
This follows bd60ce86520b ('nptl: Move pthread_atfork to libc_nonshared.a')
with the same rationale: there is no non-libpthread equivalent to be used
for making linking against libpthread optional.
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.
This patch avoid probing the __NR_clock_getttime64 syscall each time
__clock_gettime64 is issued on a kernel without 64 bit time support.
Once ENOSYS is obtained, only 32-bit clock_gettime are used.
No architecture currently defines the vDSO symbol. On archictures
with 64-bit time_t the HAVE_CLOCK_GETRES_VSYSCALL is renamed to
HAVE_CLOCK_GETRES64_VSYSCALL, it simplifies clock_gettime code.
This patch avoid probing the __NR_clock_getttime64 syscall each time
__clock_gettime64 is issued on a kernel without 64 bit time support.
Once ENOSYS is obtained, only 32-bit clock_gettime are used.
No architecture currently defines the vDSO symbol. On architectures
with 64-bit time_t the HAVE_CLOCK_GETTIME_VSYSCALL is renamed to
HAVE_CLOCK_GETTIME64_VSYSCALL, it simplifies clock_gettime code.
This patch moves the vDSO setup from libc to loader code, just after
the vDSO link_map setup. For static case the initialization
is moved to _dl_non_dynamic_init instead.
Instead of using the mangled pointer, the vDSO data is set as
attribute_relro (on _rtld_global_ro for shared or _dl_vdso_* for
static). It is read-only even with partial relro.
It fixes BZ#24967 now that the vDSO pointer is setup earlier than
malloc interposition is called.
Also, vDSO calls should not be a problem for static dlopen as
indicated by BZ#20802. The vDSO pointer would be zero-initialized
and the syscall will be issued instead.
Checked on x86_64-linux-gnu, i686-linux-gnu, aarch64-linux-gnu,
arm-linux-gnueabihf, powerpc64le-linux-gnu, powerpc64-linux-gnu,
powerpc-linux-gnu, s390x-linux-gnu, sparc64-linux-gnu, and
sparcv9-linux-gnu. I also run some tests on mips.
The code is similar to the one at elf/dl-reloc.c, where it checks for
the l_relro_size from the link_map (obtained from PT_GNU_RELRO header
from program headers) and calls_dl_protected_relro.
For testing I will use the ones proposed by Florian's patch
'elf: Add tests for working RELRO protection' [1].
Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc64le-linux-gnu,
aarch64-linux-gnu, s390x-linux-gnu, and sparc64-linux-gnu. I also
check with --enable-static pie on x86_64-linux-gnu, i686-linux-gnu,
and aarch64-linux-gnu which seems the only architectures where
static PIE is actually working (as per 9d7a3741c9e, on
arm-linux-gnueabihf, powerpc64{le}-linux-gnu, and s390x-linux-gnu
I am seeing runtime issues not related to my patch).
The IFUNC bypass to vDSO is used when USE_IFUNC_TIME is set.
Currently powerpc and x86 defines it. Otherwise the generic
implementation is used, which calls clock_gettime.
Checked on powerpc64le-linux-gnu, powerpc64-linux-gnu,
powerpc-linux-gnu-power4, x86_64-linux-gnu, and i686-linux-gnu.
The IFUNC bypass to vDSO is used when USE_IFUNC_GETTIMEOFDAY is set.
Currently aarch64, powerpc*, and x86 defines it. Otherwise the
generic implementation is used, which calls clock_gettime.
Checked on aarch64-linux-gnu, powerpc64le-linux-gnu,
powerpc64-linux-gnu, powerpc-linux-gnu-power4, x86_64-linux-gnu,
and i686-linux-gnu.
- It requires sync the auto-generated C file with current glibc
implementation;
- It still uses symbol redirections hacks where libc-symbols.h
provide macros that uses compiler builtins
(libc_ifunc_redirected for instance);
- It does not handle all required compiler handling
(inhibit_stack_protector on iFUNC resolver).
- No architecure uses it.
This is the only use of auto-generation syscall which uses a vDSO
plus IFUNC and the current x86 generic implementation already covers
the expected semantic.
linux: Fix vDSO macros build with time64 interfaces
As indicated on libc-help [1] the ec138c67cb commit broke 32-bit
builds when configured with --enable-kernel=5.1 or higher. The
scenario 10 from [2] might also occur in this configuration and
INLINE_VSYSCALL will try to use the vDSO symbol and
HAVE_CLOCK_GETTIME64_VSYSCALL does not set HAVE_VSYSCALL prior its
usage.
Also, there is no easy way to just enable the code to use one
vDSO symbol since the macro INLINE_VSYSCALL is redefined if
HAVE_VSYSCALL is set.
Instead of adding more pre-processor handling and making the code
even more convoluted, this patch removes the requirement of defining
HAVE_VSYSCALL before including sysdep-vdso.h to enable vDSO usage.
The INLINE_VSYSCALL is now expected to be issued inside a
HAVE_*_VSYSCALL check, since it will try to use the internal vDSO
pointers.
Both clock_getres and clock_gettime vDSO code for time64_t were
removed since there is no vDSO setup code for the symbol (an
architecture can not set HAVE_CLOCK_GETTIME64_VSYSCALL).
Checked on i686-linux-gnu (default and with --enable-kernel=5.1),
x86_64-linux-gnu, aarch64-linux-gnu, and powerpc64le-linux-gnu.
I also checked against a build to mips64-linux-gnu and
sparc64-linux-gnu.
The result of INTERNAL_SYSCALL_CANCEL should be checked with
macros INTERNAL_SYSCALL_ERROR_P and INTERNAL_SYSCALL_ERRNO instead
of comparing the result directly.
This patch adds a new macro, libm_alias_finite, to define all _finite
symbol. It sets all _finite symbol as compat symbol based on its first
version (obtained from the definition at built generated first-versions.h).
The <fn>f128_finite symbols were introduced in GLIBC 2.26 and so need
special treatment in code that is shared between long double and float128.
It is done by adding a list, similar to internal symbol redifinition,
on sysdeps/ieee754/float128/float128_private.h.
Alpha also needs some tricky changes to ensure we still emit 2 compat
symbols for sqrt(f).
Rafał Lużyński [Mon, 30 Dec 2019 10:58:18 +0000 (11:58 +0100)]
Multiple locales: Add date_fmt (bug 24054)
It is not specified what should be the content of d_t_fmt and date_fmt
but in the built-in C locale those fields have only one difference:
date_fmt contains "%Z" (the current time zone) while d_t_fmt does not.
For most of the locales this commit does the following operation:
copy d_t_fmt to date_fmt, and then remove "%Z" from d_t_fmt.
If "%Z" was originally missing from d_t_fmt add it to date_fmt.
It also corrects comments where necessary.
Exceptions:
* In bo_CN, dz_BT, and km_KH "%Z" has not been added to date_fmt because
it was too difficult. In these locales date_fmt has been set to the
copy of d_t_fmt.
* In en_DK "%Z" has not been removed from d_t_fmt in order to preserve
the conformance with the standard mentioned in the comment.
The command to identify and initially edit the locales that need the
update was:
for i in `grep -lw d_t_fmt *`
do
if ! grep -qw date_fmt $i ; then
awk '/d_t_fmt/ { print $0; gsub("d_t_fmt", "date_fmt"); } //{ print $0 }' < $i > $i.next
mv $i.next $i
fi
done
Hurd uses an empty prefix, so the linker scripts end up in /lib, the
find command picked them up, and stripping them failed because they
are not ELF files.
Florian Weimer [Thu, 2 Jan 2020 09:18:37 +0000 (10:18 +0100)]
Linux: Remove pread/pread64, pwrite/pwrite64 kludges from <sysdep.h>
Since the switch away from auto-generated wrappers for these system
calls, the kludge is already included in the C source file of the
system call wrapper.
This command uses pre-built compilers to re-install the Linux headers
from the current sources into a temporary location and runs glibc's
“make update-syscalls-lists” against that. This updates the glibc
source tree with the current system call numbers.
The new classes GlibcPolicyForCompiler and GlibcPolicyForBuild allow
customization of the Glibc.build_glibc method, replacing the existing
for_compiler flag.
Florian Weimer [Thu, 2 Jan 2020 09:18:22 +0000 (10:18 +0100)]
Linux: Use system call tables during build
Use <arch-syscall.h> instead of <asm/unistd.h> to obtain the system
call numbers. A few direct includes of <asm/unistd.h> need to be
removed (if the system call numbers are already provided indirectly
by <sysdep.h>) or replaced with <sys/syscall.h>.
Current Linux headers for alpha define the required system call names,
so most of the _NR_* hacks are no longer needed. For the 32-bit arm
architecture, eliminate the INTERNAL_SYSCALL_ARM macro, now that we
have regular system call names for cacheflush and set_tls. There are
more such cleanup opportunities for other architectures, but these
cleanups are required to avoid macro redefinition errors during the
build.
For ia64, it is desirable to use <asm/break.h> directly to obtain
the break number for system calls (which is not a system call number
itself). This requires replacing __BREAK_SYSCALL with
__IA64_BREAK_SYSCALL because the former is defined as an alias in
<asm/unistd.h>, but not in <asm/break.h>.
Florian Weimer [Thu, 2 Jan 2020 09:18:10 +0000 (10:18 +0100)]
Linux: Add tables with system call numbers
The new tables are currently only used for consistency checks
with the installed kernel headers and the architecture-independent
system call names table. They are based on Linux 5.4.
The goal is to use these architecture-specific tables to ensure
that system call wrappers are available irrespective of the version
of the installed kernel headers.
The tables are formatted in the form of C header files so that they
can be used directly in an #include directive, without external
preprocessing. (External preprocessing of a plain table file
would introduce cross-subdirectory dependency issues.) However,
the intent is that they can still be treated as tables and can be
processed by simple tools.
The irregular system call names on 32-bit arm add a complication.
The <fixup-asm-unistd.h> header is introduced to work around that,
and the system calls are listed under regular names in the
<arch-syscall.h> file.
A make target, update-syscalls-list, is added to patch the glibc
sources with data from the current kernel headers.
Joseph Myers [Wed, 1 Jan 2020 00:21:22 +0000 (00:21 +0000)]
Update copyright dates not handled by scripts/update-copyrights.
I've updated copyright dates in glibc for 2020. This is the patch for
the changes not generated by scripts/update-copyrights and subsequent
build / regeneration of generated files. As well as the usual annual
updates, mainly dates in --version output (minus libc.texinfo which
previously had to be handled manually but is now successfully updated
by update-copyrights), there is a fix to
sysdeps/unix/sysv/linux/powerpc/bits/termios-c_lflag.h where a typo in
the copyright notice meant it failed to be updated automatically.
Please remember to include 2020 in the dates for any new files added
in future (which means updating any existing uncommitted patches you
have that add new files to use the new copyright dates in them).
Rafał Lużyński [Mon, 30 Dec 2019 10:42:46 +0000 (11:42 +0100)]
lv_LV locale: Correct the time part of d_t_fmt (bug 25324)
Currently d_t_fmt formats time as "plkst. %H un %M". A quick Google
search says that "plkst." means "o’clock" and "un" means "and".
Also this format does not display seconds.
CLDR does not mention anything like that. We have no reason to use
anything different than "%H:%M:%S".
Jeremie Koenig [Sun, 29 Dec 2019 16:59:55 +0000 (17:59 +0100)]
hurd: Global signal disposition
This adds _hurd_sigstate_set_global_rcv used by libpthread to enable
POSIX-confirming behavior of signals on a per-thread basis.
This also provides a sigstate destructor _hurd_sigstate_delete, and a
global process signal state, which needs to be locked and check when
global disposition is enabled, thus the addition of _hurd_sigstate_lock
_hurd_sigstate_actions _hurd_sigstate_pending _hurd_sigstate_unlock helpers.
This also updates all the glibc code accordingly.
This also drops support for get_int(INIT_SIGMASK), which did not make sense
any more since we do not have a single signal thread any more.
During fork/spawn, this also reinitializes the child global sigstate's
lock. That cures an issue that would very rarely cause a deadlock in the
child in fork, tries to unlock ss' critical section lock at the end of
fork. This will typically (always?) be observed in /bin/sh, which is not
surprising as that is the foremost caller of fork.
To reproduce an intermediate state, add an endless loop if
_hurd_global_sigstate is locked after __proc_dostop (cast through
volatile); that is, while still being in the fork's parent process.
When that triggers (use the libtool testsuite), the signal thread has
already locked ss (which is _hurd_global_sigstate), and is stuck at
hurdsig.c:685 in post_signal, trying to lock _hurd_siglock (which the
main thread already has locked and keeps locked until after
__task_create). This is the case that ss->thread == MACH_PORT_NULL, that
is, a global signal. In the main thread, between __proc_dostop and
__task_create is the __thread_abort call on the signal thread which would
abort any current kernel operation (but leave ss locked). Later in fork,
in the parent, when _hurd_siglock is unlocked in fork, the parent's
signal thread can proceed and will unlock eventually the global sigstate.
In the client, _hurd_siglock will likewise be unlocked, but the global
sigstate never will be, as the client's signal thread has been configured
to restart execution from _hurd_msgport_receive. Thus, when the child
tries to unlock ss' critical section lock at the end of fork, it will
first lock the global sigstate, will spin trying to lock it, which can
never be successful, and we get our deadlock.
Options seem to be:
* Move the locking of _hurd_siglock earlier in post_signal -- but that
may generally impact performance, if this locking isn't generally
needed anyway?
On the other hand, would it actually make sense to wait here until we
are not any longer in a critical section (which is meant to disable
signal delivery anyway (but not for preempted signals?))?
* Clear the global sigstate in the fork's child with the rationale that
we're anyway restarting the signal thread from a clean state. This
has now been implemented.
Why has this problem not been observed before Jérémie's patches? (Or has
it? Perhaps even more rarely?) In _S_msg_sig_post, the signal is now
posted to a *global receiver thread*, whereas previously it was posted to
the *designated signal-receiving thread*. The latter one was in a
critical section in fork, so didn't try to handle the signal until after
leaving the critical section? (Not completely analyzed and verified.)
Another question is what the signal is that is being received
during/around the time __proc_dostop executes.
Jeremie Koenig [Sun, 29 Dec 2019 16:18:04 +0000 (17:18 +0100)]
hurd: Signal code refactoring
This should not change the current behavior, although this fixes a few
minor bugs which were made apparent in the process of global signal
disposition work:
- Split into more functions
- Scope variables more restrictively
- Split out inner functions
- refactor check_pending_signals
- make sigsuspend POSIX-conformant.
- fix uninitialized act value.
Not thoroughly tested, but manual testing as well as glibc tests look fine, and
manual -lpthread testing also looks fine (within the given bounds for a new
stack to be used with makecontext).
ldbl-128ibm-compat: Do not mix -mabi=*longdouble and -mlong-double-128
Some compiler versions, e.g. GCC 7, complain when -mlong-double-128 is
used together with -mabi=ibmlongdouble or -mabi=ieeelongdouble,
producing the following error message:
ldbl-128ibm-compat: Compiler flags for stdio functions
Some of the files that provide stdio.h and wchar.h functions have a
filename prefixed with 'io', such as 'iovsprintf.c'. On platforms that
imply ldbl-128ibm-compat, these files must be compiled with the flag
-mabi=ibmlongdouble. This patch adds this flag to their compilation.
Notice that this is not required for the other files that provide
similar functions, because filenames that are not prefixed with 'io'
have ldbl-128ibm-compat counterparts in the Makefile, which already adds
-mabi=ibmlongdouble to them.
Reviewed-by: Gabriel F. T. Gomes <gabrielftg@linux.ibm.com>
Do not redirect calls to __GI_* symbols, when redirecting to *ieee128
On platforms where long double has IEEE binary128 format as a third
option (initially, only powerpc64le), many exported functions are
redirected to their __*ieee128 equivalents. This redirection is
provided by installed headers such as stdio-ldbl.h, and is supposed to
work correctly with user code.
However, during the build of glibc, similar redirections are employed,
in internal headers, such as include/stdio.h, in order to avoid extra
PLT entries. These redirections conflict with the redirections to
__*ieee128, and must be avoided during the build. This patch protects
the second redirections with a test for __LONG_DOUBLE_USES_FLOAT128, a
new macro that is defined to 1 when functions that deal with long double
typed values reuses the _Float128 implementation (this is currently only
true for powerpc64le).
Tested for powerpc64le, x86_64, and with build-many-glibcs.py.
Co-authored-by: Gabriel F. T. Gomes <gabrielftg@linux.ibm.com> Reviewed-by: Florian Weimer <fweimer@redhat.com>
The functions do not fail regardless of the argument value. Also, for
Linux the return value is not correct on some platforms due the missing
usage of INTERNAL_SYSCALL_ERROR_P / INTERNAL_SYSCALL_ERRNO macros.
Checked on x86_64-linux-gnu, i686-linux-gnu, and sparc64-linux-gnu.
Avoid compat symbols for totalorder in powerpc64le IEEE long double
On powerpc64le, the libm_alias_float128_other_r_ldbl macro is
used to create an alias between totalorderf128 and __totalorderlieee128,
as well as between the totalordermagf128 and __totalordermaglieee128.
However, the totalorder* and totalordermag* functions changed their
parameter type since commit ID 42760d764649 and got compat symbols for
their old versions. With this change, the aforementioned macro would
create two conflicting aliases for __totalorderlieee128 and
__totalordermaglieee128.
This patch avoids the creation of the alias between the IEEE long double
symbols (__totalorderl*ieee128) and the compat symbols, because the IEEE
long double functions have never been exported thus don't need such
compat symbol.
Tested for powerpc64le.
Reviewed-by: Joseph Myers <joseph@codesourcery.com>
This patch adds IEEE long double versions of q*cvt* functions for
powerpc64le. Unlike all other long double to/from string conversion
functions, these do not rely on internal functions that can take
floating-point numbers with different formats and act on them
accordingly, instead, the related files are rebuilt with the
-mabi=ieeelongdouble compiler flag set.
Having -mabi=ieeelongdouble passed to the compiler causes the object
files to be marked with a .gnu_attribute that is incompatible with the
.gnu_attribute in files built with -mabi=ibmlongdouble (the default).
The difference causes error messages similar to the following:
ld: libc_pic.a(s_isinfl.os) uses IBM long double,
libc_pic.a(ieee128-qefgcvt_r.os) uses IEEE long double.
collect2: error: ld returned 1 exit status
make[2]: *** [../Makerules:649: libc_pic.os] Error 1
Although this warning is useful in other situations, the library
actually needs to have functions with different long double formats, so
.gnu_attribute generation is explicitly disabled for these files with
the use of -mno-gnu-attribute.
Tested for powerpc64le on the branch that actually enables the
sysdeps/ieee754/ldbl-128ibm-compat for powerpc64le.
Reviewed-by: Paul E. Murphy <murphyp@linux.ibm.com>
This patch refactors the *cvt functions implementation in a way that
makes it easier to re-use them for implementing the IEEE long double on
powerpc64le. By removing the macros that generate the function names
(APPEND combined with FUNC_PREFIX), the new code makes it easier to
define new function names, such as __qecvtieee128.
Tested that installed stripped binaries for all build-many-glibcs
targets remain identical before and after this patch. Also tested for
powerpc64le and x86_64.
Reviewed-by: Paul E. Murphy <murphyp@linux.ibm.com>
This patch refactors the *cvt functions implementation in a way that
makes it easier to re-use them for implementing the IEEE long double on
powerpc64le. By splitting the implementation per se in one file
(efgcvt-template.c) and the alias definitions in others (e.g. efgcvt.c),
the new code makes it easier to define new function names, such as
__qecvtieee128.
Tested that installed stripped binaries for all build-many-glibcs
targets remain identical before and after this patch. Also tested for
powerpc64le and x86_64.
Reviewed-by: Paul E. Murphy <murphyp@linux.ibm.com>
Xuelei Zhang [Thu, 19 Dec 2019 15:26:33 +0000 (15:26 +0000)]
aarch64: Optimized memset for Kunpeng processor.
Due to the branch prediction issue of Kunpeng processor, we found
memset_generic has poor performance on middle sizes setting, and so
we reconstructed the logic, expanded the loop by 4 times in set_long
to solve the problem, even when setting below 1K sizes have benefit.
Another change is that DZ_ZVA seems no work when setting zero, so we
discarded it and used set_long to set zero instead. Fewer branches and
predictions also make the zero case have slightly improvement.
Xuelei Zhang [Thu, 19 Dec 2019 13:41:40 +0000 (13:41 +0000)]
aarch64: Optimized strlen for strlen_asimd
Optimize the strlen implementation by using vector operations and
loop unrolling in main loop.Compared to __strlen_generic,it reduces
latency of cases in bench-strlen by 7%~18% when the length of src
is greater than 128 bytes, with gains throughout the benchmark.
git://sourceware.org / glibc.git / log