commit 6f573a27b6
Author: Noah Goldstein <goldstein.w.n@gmail.com>
Date: Wed Jun 23 01:19:34 2021 -0400
x86-64: Add wcslen optimize for sse4.1
added wcsnlen-sse4.1 to the wcslen ifunc implementation list. Since the
random value in the the RSI register is larger than the wide-character
string length in the existing wcslen test, it didn't trigger the wcslen
test failure. Add a test to force 0 into the RSI register before calling
wcslen.
https://sourceware.org/bugzilla/show_bug.cgi?id=21782 dropped an ld
diagnostic for R_X86_64_PC32 referencing an undefined weak symbol in
-pie links. Arguably keeping the diagnostic like other ports is more
correct, since statically resolving movl foo(%rip), %eax to the
link-time zero address produces a corrupted output.
It turns out that --enable-static-pie builds do not depend on the ld
behavior. GCC generates GOT indirection for weak declarations for
-fPIE/-fPIC, so what ld does with the PC-relative relocation doesn't
really matter.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
This patch adds a way to close a range of file descriptors on
posix_spawn as a new file action. The API is similar to the one
provided by Solaris 11 [1], where the file action causes the all open
file descriptors greater than or equal to input on to be closed when
the new process is spawned.
The function posix_spawn_file_actions_addclosefrom_np is safe to be
implemented by iterating over /proc/self/fd, since the Linux spawni.c
helper process does not use CLONE_FILES, so its has own file descriptor
table and any failure (in /proc operation) aborts the process creation
and returns an error to the caller.
I am aware that this file action might be redundant to the current
approach of POSIX in promoting O_CLOEXEC in more interfaces. However
O_CLOEXEC is still not the default and for some specific usages, the
caller needs to close all possible file descriptors to avoid them
leaking. Some examples are CPython (discussed in BZ#10353) and OpenJDK
jspawnhelper [2] (where OpenJDK spawns a helper process to exactly
closes all file descriptors). Most likely any environment which calls
functions that might open file descriptor under the hood and aim to use
posix_spawn might face the same requirement.
Checked on x86_64-linux-gnu and i686-linux-gnu on kernel 5.11 and 4.15.
[1] https://docs.oracle.com/cd/E36784_01/html/E36874/posix-spawn-file-actions-addclosefrom-np-3c.html
[2] https://github.com/openjdk/jdk/blob/master/src/java.base/unix/native/libjava/childproc.c#L82
The function closes all open file descriptors greater than or equal to
input argument. Negative values are clamped to 0, i.e, it will close
all file descriptors.
As indicated by the bug report, this is a common symbol provided by
different systems (Solaris, OpenBSD, NetBSD, FreeBSD) and, although
its has inherent issues with not taking in consideration internal libc
file descriptors (such as syslog), this is also a common feature used
in multiple projects [1][2][3][4][5].
The Linux fallback implementation iterates over /proc and close all
file descriptors sequentially. Although it was raised the questioning
whether getdents on /proc/self/fd might return disjointed entries
when file descriptor are closed; it does not seems the case on my
testing on multiple kernel (v4.18, v5.4, v5.9) and the same strategy
is used on different projects [1][2][3][5].
Also, the interface is set a fail-safe meaning that a failure in the
fallback results in a process abort.
Checked on x86_64-linux-gnu and i686-linux-gnu on kernel 5.11 and 4.15.
[1] 5238e95759/src/basic/fd-util.c (L217)
[2] ddf4b77e11/src/lxc/start.c (L236)
[3] 9e4f2f3a6b/Modules/_posixsubprocess.c (L220)
[4] 5f47c0613e/src/libstd/sys/unix/process2.rs (L303-L308)
[5] https://github.com/openjdk/jdk/blob/master/src/java.base/unix/native/libjava/childproc.c#L82
It was added on Linux 5.9 (278a5fbaed89) with CLOSE_RANGE_CLOEXEC
added on 5.11 (582f1fb6b721f). Although FreeBSD has added the same
syscall, this only adds the symbol on Linux ports. This syscall is
required to provided a fail-safe way to implement the closefrom
symbol (BZ #10353).
Checked on x86_64-linux-gnu and i686-linux-gnu on kernel 5.11 and 4.15.
This patch updates the kernel version in the test tst-mman-consts.py
to 5.13. (There are no new MAP_* constants covered by this test in
5.13 that need any other header changes.)
Tested with build-many-glibcs.py.
Now that there are no internal users anymore, these new symbol
versions can be removed from the public ABI. The compatibility
symbols remain.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This avoids an ABI hazard (types changing between different modules
of glibc) without introducing linknamespace issues. In particular,
NSS modules now call __lll_lock_wait_private@@GLIBC_PRIVATE to wait
on internal locks (the unlock path is inlined and performs a direct
system call).
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This patch consolidates the setsockopt implementation on
sysdeps/unix/sysv/linux/getsockopt.c. The changes are:
1. Remove it from auto-generation syscalls.list on all architectures.
2. Add __ASSUME_SETSOCKOPT_SYSCALL as default and undef if for
specific kernel versions on some architectures.
This also fix a potential issue where 32-bit time_t ABI should use the
linux setsockopt which overrides the underlying SO_* constants used for
socket timestamping for _TIME_BITS=64.
Checked on x86_64-linux-gnu and i686-linux-gnu.
This patch consolidates the getsockopt Linux syscall implementation on
sysdeps/unix/sysv/linux/getsockopt.c. The changes are:
1. Remove it from auto-generation syscalls.list on all architectures.
2. Add __ASSUME_GETSOCKOPT_SYSCALL as default and undef if for
specific kernel versions on some architectures.
This also fix a potential issue where 32-bit time_t ABI should use the
linux getsockopt which overrides the underlying SO_* constants used for
socket timestamping for _TIME_BITS=64.
Checked on x86_64-linux-gnu and i686-linux-gnu.
This avoids crashes in libc when cmsg is null and refrencing msg
structure when it is null
Signed-off-by: Khem Raj <raj.khem@gmail.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The symbols gai_cancel, gai_error, gai_suspend, getaddrinfo_a,
__gai_suspend_time64 were moved using scripts/move-symbol-to-libc.py.
For Hurd (which remains !PTHREAD_IN_LIBC), a few #define redirects
had to be added because several pthread functions are not available
under __. (Linux uses __ prefixes for most hidden aliases, and has
to in some cases to avoid linknamespace issues.)
This patch modifies the current POWER9 implementation of strcpy and
stpcpy to optimize it for POWER9/10.
Since no new POWER10 instructions are used, the original POWER9 strcpy is
modified instead of creating a new implementation for POWER10. This
implementation is based on both the original POWER9 implementation of
strcpy and the preamble of the new POWER10 implementation of strlen.
The changes also affect stpcpy, which uses the same implementation with
some additional code before returning.
On POWER9, averaging improvements across the benchmark
inputs (length/source alignment/destination alignment), for an
experiment that ran the benchmark five times, bench-strcpy showed an
improvement of 5.23%, and bench-stpcpy showed an improvement of 6.59%.
On POWER10, bench-strcpy showed 13.16%, and bench-stpcpy showed 13.59%.
The changes are:
1. Removed the null string optimization.
Although this results in a few extra cycles for the null string, in
combination with the second change, this resulted in improvements for
for other cases.
2. Adapted the preamble from strlen for POWER10.
This is the part of the function that handles up to the first 16 bytes
of the string.
3. Increased number of unrolled iterations in the main loop to 6.
Reviewed-by: Matheus Castanho <msc@linux.ibm.com>
Tested-by: Matheus Castanho <msc@linux.ibm.com>
From
https://www.intel.com/content/www/us/en/support/articles/000059422/processors.html
* Intel TSX will be disabled by default.
* The processor will force abort all Restricted Transactional Memory (RTM)
transactions by default.
* A new CPUID bit CPUID.07H.0H.EDX[11](RTM_ALWAYS_ABORT) will be enumerated,
which is set to indicate to updated software that the loaded microcode is
forcing RTM abort.
* On processors that enumerate support for RTM, the CPUID enumeration bits
for Intel TSX (CPUID.07H.0H.EBX[11] and CPUID.07H.0H.EBX[4]) continue to
be set by default after microcode update.
* Workloads that were benefited from Intel TSX might experience a change
in performance.
* System software may use a new bit in Model-Specific Register (MSR) 0x10F
TSX_FORCE_ABORT[TSX_CPUID_CLEAR] functionality to clear the Hardware Lock
Elision (HLE) and RTM bits to indicate to software that Intel TSX is
disabled.
1. Add RTM_ALWAYS_ABORT to CPUID features.
2. Set RTM usable only if RTM_ALWAYS_ABORT isn't set. This skips the
string/tst-memchr-rtm etc. testcases on the affected processors, which
always fail after a microcde update.
3. Check RTM feature, instead of usability, against /proc/cpuinfo.
This fixes BZ #28033.
Linux 5.13 has three new syscalls (landlock_create_ruleset,
landlock_add_rule, landlock_restrict_self). Update syscall-names.list
and regenerate the arch-syscall.h headers with build-many-glibcs.py
update-syscalls.
Tested with build-many-glibcs.py.
On s390 (31bit), the pointer to the first byte after s always wraps
around with n >= 0x80000000 and can lead to stop searching before
end of s.
Thus this patch just use NULL as byte after s in this case and
the srst instruction stops searching with "not found" when wrapping
around from top address to zero.
This is observable with testcase string/test-memchr
starting with commit "String: Add overflow tests for strnlen, memchr,
and strncat [BZ #27974]"
https://sourceware.org/git/?p=glibc.git;a=commit;h=da5a6fba0febbfc90896ce1b2eb75c6d8a88a72d
Starting with recent commit 84f7ce8447
"posix: Add glob64 with 64-bit time_t support", elf/check-localplt
fails due to extra PLT reference __glob64_time64 in __glob64_time64
itself.
This is observable with gcc 7.5 on x86_64 with -m32 or s390x with
-m31. E.g. if build with gcc 10, gcc is generating a call to
__glob64_time64.localalias.
This patch is adding a hidden version of __glob64_time64 in the
same way as for __globfree64_time64.
Add hp-timing.h using the cntvct_el0 counter. Return timing in nanoseconds
so it is fully compatible with generic hp-timing. Don't set HP_TIMING_INLINE
in the dynamic linker since it adds unnecessary overheads and some ancient
kernels may not handle emulating cntcvt correctly. Currently cntvct_el0 is
only used for timing in the benchtests.
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
Optimize strnlen by avoiding UMINV which is slow on most cores. On Neoverse N1
large strings are 1.8x faster than the current version, and bench-strnlen is
50% faster overall. This version is MTE compatible.
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
malloc initialization depends on __get_nprocs, so using
scratch buffers in __get_nprocs may result in infinite recursion.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
The symbols forkpty, login, login_tty, logout, logwtmp, openpty
were moved using scripts/move-symbol-to-libc.py.
This is a single commit because most of the symbols are tied together
via forkpty, for example.
Several changes to use hidden prototypes are needed. This commit
also updates pseudoterminal terminology on modified lines.
For 390 (31-bit), this commit follows the existing style for the
compat symbol version creation.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
RFC 8335 defines the network utility PROBE, which builds off of the
capabilities of Ping to query more detailed interface information from
networking nodes.
The definitions included in this patchset have been accepted into the
linux net-next branch and will be included in Linux 5.13. This
patchset adds the same definitions to the glibc for use in the
iputils package.
The relevant commits for the Linux definitions can be found here:
e542d29ca8750f4fc2a1
These changes have been tested by running the glibc tests on x86_64
Signed-off-by: Andreas Roeseler <andreas.a.roeseler@gmail.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
After recent commit
447954a206
"math: redirect roundeven function", building on
s390x fails with:
Error: symbol `__roundevenl' is already defined
Similar to aarch64/riscv fix, this patch redirects target
specific functions for s390x:
commit 3213ed770c
"Update math: redirect roundeven function"
Austin Group issue 62 [1] dropped the async-signal-safe requirement
for fork and provided a async-signal-safe _Fork replacement that
does not run the atfork handlers. It will be included in the next
POSIX standard.
It allow to close a long standing issue to make fork AS-safe (BZ#4737).
As indicated on the bug, besides the internal lock for the atfork
handlers itself; there is no guarantee that the handlers itself will
not introduce more AS-safe issues.
The idea is synchronize fork with the required internal locks to allow
children in multithread processes to use mostly of standard function
(even though POSIX states only AS-safe function should be used). On
signal handles, _Fork should be used intead and only AS-safe functions
should be used.
For testing, the new tst-_Fork only check basic usage. I also added
a new tst-mallocfork3 which uses the same strategy to check for
deadlock of tst-mallocfork2 but using threads instead of subprocesses
(and it does deadlock if it replaces _Fork with fork).
[1] https://austingroupbugs.net/view.php?id=62
The valgrind/helgrind test suite needs a way to make stack dealloction
more prompt, and this feature seems to be generally useful.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
librt.so is no longer installed for PTHREAD_IN_LIBC, and tests
are not linked against it. $(librt) is introduced globally for
shared tests that need to be linked for both PTHREAD_IN_LIBC
and !PTHREAD_IN_LIBC.
GLIBC_PRIVATE symbols that were needed during the transition are
removed again.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
The symbols were moved using scripts/move-symbol-to-libc.py.
The way the ABI intransition is implemented is changed with this
commit: the implementation is now consolidated in one file with a
TIMER_T_WAS_INT_COMPAT check.
The shared librt is now empty, so this commit adds a placeholder
symbol at the base version, GLIBC_2.2, and potentially at the
GLIBC_2.3.3 version as well (the leftover from the int/timer_t ABI
transition).
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The symbols were moved using scripts/move-symbol-to-libc.py.
The way the ABI intransition is implemented is changed with this
commit: the implementation is now consolidated in one file with a
TIMER_T_WAS_INT_COMPAT check.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The symbol was moved using scripts/move-symbol-to-libc.py.
The way the ABI intransition is implemented is changed with this
commit: the implementation is now consolidated in one file with a
TIMER_T_WAS_INT_COMPAT check.
Reviewed-by: Adhemerva Zanella <adhemerval.zanella@linaro.org>
The symbols were moved using scripts/move-symbol-to-libc.py.
timer_create and timer_delete are tied together via the int/timer_t
compatibility code. The way the ABI intransition is implemented
is changed with this commit: the implementation is now consolidated
in one file with a TIMER_T_WAS_INT_COMPAT check.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This is almost equivalent to __WORDSIZE == 64
&& OTHER_SHLIB_COMPAT (librt, GLIBC_2_1, GLIBC_2_3_3), except
that this expression is true for mips64/n64 targets as well,
even though those did not undergo the timer_t transition.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
This patch is using the corresponding GCC builtin for roundevenf,
roundeven and roundevenl if the USE_FUNCTION_BUILTIN macros are defined
to one in math-use-builtins.h.
These builtin functions is supported since GCC 10.
The code of the generic implementation is not changed.
Signed-off-by: Shen-Ta Hsieh <ibmibmibm.tw@gmail.com>
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
This patch redirect roundeven function for futhermore changes.
Signed-off-by: Shen-Ta Hsieh <ibmibmibm.tw@gmail.com>
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
This adds several temporary GLIBC_PRIVATE exports. The symbol names
are changed so that they all start with __timer_.
It is now possible to invoke the fork handler directly, so
pthread_atfork is no longer necessary. The associated error cannot
happen anymore, and cancellation handling can be removed from
the helper thread routine.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The symbol was moved using scripts/move-symbol-to-libc.py.
A placeholder symbol is needed on some architectures for the
GLIBC_2.3.4 version.
Reviewed-by: Adhemerva Zanella <adhemerval.zanella@linaro.org>
The symbols were moved using scripts/move-symbol-to-libc.py.
A placeholder symbol is required to keep the GLIBC_2.7 version.
Reviewed-by: Adhemerva Zanella <adhemerval.zanella@linaro.org>
The symbol was moved using scripts/move-symbol-to-libc.py.
An explicit call from fork into the mq_notify implementation replaces
the previous use of pthread_atfork.
Reviewed-by: Adhemerva Zanella <adhemerval.zanella@linaro.org>
The symbol was moved using scripts/move-symbol-to-libc.py.
To introduce the proper symbol versioning, the implementation of
the system call wrapper us moved to a C file.
Reviewed-by: Adhemerva Zanella <adhemerval.zanella@linaro.org>