This patch does some initial cleanup, following the move to 2.6.32
minimum kernel version, by removing __LINUX_KERNEL_VERSION
conditionals that are now always-true or always-false. In the case of
__ASSUME_ARG_MAX_STACK_BASED, where the conditional used a kernel
version that was itself in a macro, the associated sysconf.c code is
also cleaned up and __ASSUME_ARG_MAX_STACK_BASED removed completely.
Tested x86_64 that disassembly of installed shared libraries is
unchanged by the patch.
* sysdeps/unix/sysv/linux/kernel-features.h [__s390__]
(__ASSUME_UTIMES): Do not condition on kernel version.
(__ASSUME_PSELECT): Define unconditionally.
(__ASSUME_PPOLL): Likewise.
(__ASSUME_ATFCTS): Likewise.
(__ASSUME_SET_ROBUST_LIST): Do not condition on kernel version.
(__ASSUME_COMPLETE_READV_WRITEV): Define unconditionally.
(__ASSUME_FUTEX_LOCK_PI): Do not condition on kernel version.
(__ASSUME_UTIMENSAT): Define unconditionally.
(__ASSUME_PRIVATE_FUTEX): Likewise.
(__ASSUME_FALLOCATE): Likewise.
(__ASSUME_O_CLOEXEC): Likewise.
(__LINUX_ARG_MAX_STACK_BASED_MIN_KERNEL): Remove.
(__ASSUME_ARG_MAX_STACK_BASED): Likewise.
(__ASSUME_ADJ_OFFSET_SS_READ): Define unconditionally.
(__ASSUME_SOCK_CLOEXEC): Do not condition on kernel version.
(__ASSUME_IN_NONBLOCK): Likewise.
(__ASSUME_PIPE2): Likewise.
(__ASSUME_EVENTFD2): Likewise.
(__ASSUME_SIGNALFD4): Likewise.
(__ASSUME_DUP3): Likewise.
[__x86_64__ || __sparc__] (__ASSUME_ACCEPT4_SYSCALL): Likewise.
(__ASSUME_FUTEX_CLOCK_REALTIME): Define unconditionally.
(__ASSUME_AT_RANDOM): Likewise.
(__ASSUME_PREADV): Likewise.
(__ASSUME_PWRITEV): Likewise.
(__ASSUME_REQUEUE_PI): Do not condition on kernel version.
(__ASSUME_F_GETOWN_EX): Define unconditionally.
(__ASSUME_XFS_RESTRICTED_CHOWN): Likewise.
* sysdeps/unix/sysv/linux/sysconf.c (__sysconf)
[!__ASSUME_ARG_MAX_STACK_BASED]: Remove conditional code.
* sysdeps/unix/sysv/linux/alpha/kernel-features.h
(__ASSUME_O_CLOEXEC): Define unconditionally.
(__ASSUME_PSELECT): Do not undefine conditionally.
(__ASSUME_PPOLL): Likewise.
(__ASSUME_ATFCTS): Likewise.
(__ASSUME_SET_ROBUST_LIST): Likewise.
(__ASSUME_UTIMENSAT): Likewise.
(__ASSUME_FDATASYNC): Define unconditionally.
* sysdeps/unix/sysv/linux/arm/kernel-features.h
(__ASSUME_SIGFRAME_V2): Likewise.
)__ASSUME_EVENTFD2): Likewise.
(__ASSUME_SIGNALFD4): Likewise.
(__ASSUME_PSELECT): Do not undefine conditionally.
(__ASSUME_PPOLL): Likewise.
* sysdeps/unix/sysv/linux/ia64/kernel-features.h
(__ASSUME_PSELECT): Define unconditionally.
(__ASSUME_PPOLL): Likewise.
(__ASSUME_O_CLOEXEC): Likewise.
(__ASSUME_SOCK_CLOEXEC): Likewise.
(__ASSUME_IN_NONBLOCK): Likewise.
(__ASSUME_PIPE2): Likewise.
(__ASSUME_EVENTFD2): Likewise.
(__ASSUME_SIGNALFD4): Likewise.
(__ASSUME_DUP3): Likewise.
* sysdeps/unix/sysv/linux/m68k/kernel-features.h
(__ASSUME_O_CLOEXEC): Likewise.
(__ASSUME_SOCK_CLOEXEC): Likewise.
(__ASSUME_IN_NONBLOCK): Likewise.
(__ASSUME_PIPE2): Likewise.
(__ASSUME_EVENTFD2): Likewise.
(__ASSUME_SIGNALFD4): Likewise.
(__ASSUME_DUP3): Likewise.
* sysdeps/unix/sysv/linux/mips/kernel-features.h
(__ASSUME_EVENTFD2): Likewise.
(__ASSUME_SIGNALFD4): Likewise.
(__ASSUME_ACCEPT4_SYSCALL): Likewise.
This patch fixes the tst-tlsmod[5/6].so build in system that uses
-Wl,--as-needed as default in linker option. Without this option
the testing shared library that does not have libc.so in DT_NEEDED
and the tst-tls9-static fails in architecture that use the
./sysdeps/unix/sysv/linux/<arch>/dl-static.c trick.
This patch fixes bug 16064, i386 fenv_t not including SSE state, using
the technique suggested there of storing the state in the existing
__eip field of fenv_t to avoid needing to increase the size of fenv_t
and add new symbol versions. The included testcase, which previously
failed for i386 (but passed for x86_64), illustrates how the previous
state was buggy.
This patch causes the SSE state to be included *to the extent it is on
x86_64*. Where some state should logically be included but isn't for
x86_64 (see bug 16068), this patch does not cause it to be included
for i386 either. The idea is that any patch fixing that bug should
fix it for both x86_64 and i386 at once.
Tested i386 and x86_64. (I haven't tested the case of a CPU without
SSE2 disabling the test.)
[BZ #16064]
* sysdeps/i386/fpu/fegetenv.c: Include <unistd.h>, <ldsodefs.h>
and <dl-procinfo.h>.
(__fegetenv): Save SSE state in envp->__eip if supported.
* sysdeps/i386/fpu/feholdexcpt.c (feholdexcept): Save SSE state in
envp->__eip if supported.
* sysdeps/i386/fpu/fesetenv.c: Include <unistd.h>, <ldsodefs.h>
and <dl-procinfo.h>.
(__fesetenv): Always set __eip, __cs_selector, __opcode,
__data_offset and __data_selector in environment to 0. Set SSE
state if supported.
* sysdeps/x86/fpu/Makefile [$(subdir) = math] (tests): Add
test-fenv-sse.
[$(subdir) = math] (CFLAGS-test-fenv-sse.c): Add -msse2
-mfpmath=sse.
* sysdeps/x86/fpu/test-fenv-sse.c: New file.
Set values for libc_commonpagesize and libc_relro_required for the
ARM port to enable relro by default and suppress a warning at
configure time.
ChangeLog:
2014-05-09 Will Newton <will.newton@linaro.org>
* sysdeps/arm/preconfigure.ac: Set libc_commonpagesize
and libc_relro_required for ARM.
* sysdeps/arm/preconfigure: Regenerate.
Added support for TX lock elision of pthread mutexes on s390 and
s390x. This may improve lock scaling of existing programs on TX
capable systems. The lock elision code is only built with
--enable-lock-elision=yes and then requires a GCC version supporting
the TX builtins. With lock elision default mutexes are elided via
__builtin_tbegin, if the cpu supports transactions. By default lock
elision is not enabled and the elision code is not built.
Add an optimized implementation of strcmp for ARMv7-A cores. This
implementation is significantly faster than the current generic C
implementation, particularly for strings of 16 bytes and longer.
Tested with the glibc string tests for arm-linux-gnueabihf and
armeb-linux-gnueabihf.
The code was written by ARM, who have agreed to assign the copyright
to the FSF for integration into glibc.
ChangeLog:
2014-05-09 Will Newton <will.newton@linaro.org>
* sysdeps/arm/armv7/strcmp.S: New file.
* NEWS: Mention addition of ARMv7 optimized strcmp.
The optimization is achieved by following techniques:
> data alignment [gain from aligned memory access on read/write]
> POWER7 gains performance with loop unrolling/unwinding
[gain by reduction of branch penalty].
> zero padding done by calling optimized memset
This patch changes de default symbol redirection for internal call of
memcpy, memset, memchr, and strlen to the IFUNC resolved ones. The
performance improvement is noticeable in algorithms that uses these
symbols extensible, like the regex functions.
In 7447ccd98e, the XDR currency was
removed from locale/iso-4217.def, despite the fact that it's both
still a part of the standard, according to the official table:
http://www.currency-iso.org/dam/downloads/table_a1.xml
... and, more importantly, is referenced from localedata/i18n, so
any quick-and-dirty locale definition that uses "copy i18n" for
LC_MONETARY wouldn't work anymore.
Define FEATURE_INDEX_1 and FEATURE_INDEX_MAX as macros
for use by both assembly and C code. This fixes the
-Wundef error for cases where FEATURE_INDEX_1 was not
defined but used the correct value of 0 for an undefined
macro.
[BZ #16885]
* sysdeps/sparc/sparc64/strcmp.S: Fix end comparison handling when
multiple zero bytes exist at the end of a string.
Reported by Aurelien Jarno <aurelien@aurel32.net>
* string/test-strcmp.c (check): Add explicit test for situations where
there are multiple zero bytes after the first.
lowlevellock.c for arm differs from the generic lowlevellock.c only in
insignificant ways, so can be removed. Happily, this fixes BZ 15119
(unnecessary busy loop in __lll_timedlock_wait on arm).
The notable differences between the arm and generic implementations are:
1) arm __lll_timedlock_wait has a fast path out if futex has been set
to 0 between since the function was called. This seems unlikely to
happen very often, so it seems at worst harmless to lose this fast
path.
2) Some function in arm's lowlevellock.c set futex to 2 if it was 1.
The generic version always sets the futex to 2. As futex can only be
0, 1 or 2 on entry into these functions, the behaviour is equivalent.
(If the futex manages to be 0 on entry then we've just lost another
unlikely fast path out.)
There are no test suite regressions.
Note that hppa and sparc also have their own lowlevellock.c. I believe
hppa can also be removed, so I'll send a separate patch for that
shortly. sparc's seems to be genuinely needed as it uses a different
locking structure.
Also note that the analysis at
https://sourceware.org/ml/libc-ports/2013-02/msg00021.html indicates a
further locking performance bug to fix - I've got a partial patch for
that which I can submit once I've finished testing.
2014-05-01 Bernard Ogden <bernie.ogden@linaro.org>
[BZ #15119]
* sysdeps/unix/sysv/linux/arm/nptl/lowlevellock.c: Remove file.
This patch fixes what I believe to be a bug in the handling of
R_ARM_IRELATIVE RELA relocations. At present, these are handled the
same as REL relocations: i.e. the addend is loaded from the relocation
address. Most of the time this isn't a problem because RELA relocations
aren't used on ARM (GNU/Linux at least) anyway, but it causes problems
with prelink, which uses RELA on all targets for its conflict table.
(Support for ifunc prelinking requires a prelink patch, not yet posted.)
Anyway, this patch works, though I'm not 100% sure if it is correct: I
notice that this code path received attention last year:
https://sourceware.org/ml/libc-ports/2013-07/msg00000.html
I'm not sure under what circumstances that patch would have had an
effect, nor if my patch conflicts with that case.
No regressions using Mentor's usual glibc cross-testing infrastructure.
[BZ #16888]
* sysdeps/arm/dl-machine.h (elf_machine_rela): Fix R_ARM_IRELATIVE
handling.
This patch increases the minimum Linux kernel version for glibc to
2.6.32, as discussed in the thread starting at
<https://sourceware.org/ml/libc-alpha/2014-01/msg00511.html>.
This patch just does the minimal change to arch_minimum_kernel
settings (and LIBC_LINUX_VERSION, which determines the minimum kernel
headers version, as it doesn't make sense for that to be older than
the minimum kernel that can be used at runtime). Followups would be
expected to do, roughly and not necessarily precisely in this order:
* Remove __LINUX_KERNEL_VERSION checks in kernel-features.h files
where those checks are always true / always false for kernels 2.6.32
and above.
* Otherwise simplify/improve conditionals in those files (for example,
where defining once in the main file then undefining in
architecture-specific files makes things clearer than having lots of
separate definitions of the same macro), possibly fixing in the
process cases where a macro should optimally have been defined for a
given architecture but wasn't. (In the review in preparation for
this version increase I checked what the right conditions should be
for all macros in the main kernel-features.h whose definitions there
would have been affected by the increase - but I only fixed that
subset of the issues found where --enable-kernel=2.6.32 would have
caused a kernel feature to be wrongly assumed to be present, not any
cases where a feature is not assumed but could be assumed.)
* Remove conditionals on __ASSUME_* where they can now be taken to be
always-true, and the definitions when the macros are only used in
Linux-specific files.
* Split more architectures out of the main kernel-features.h (like
ex-ports architectures), once various of the architecture
conditionals there have been eliminated so the new
architecture-specific files are no larger than actually necessary.
Tested x86_64.
2014-03-27 Joseph Myers <joseph@codesourcery.com>
[BZ #9894]
* sysdeps/unix/sysv/linux/configure.ac (LIBC_LINUX_VERSION):
Change to 2.6.32.
(arch_minimum_kernel): Change all 2.6.16 settings to 2.6.32.
* sysdeps/unix/sysv/linux/configure: Regenerated.
* sysdeps/unix/sysv/linux/microblaze/configure.ac: Remove file.
* sysdeps/unix/sysv/linux/microblaze/configure: Likewise.
* sysdeps/unix/sysv/linux/tile/configure.ac: Likewise.
* sysdeps/unix/sysv/linux/tile/configure: Likewise.
* README: Update reference to required Linux kernel version.
* manual/install.texi (Linux): Update reference to required Linux
kernel headers version.
* INSTALL: Regenerated.
Continuing the series of patches to clean up conformtest expectations
for "POSIX" (1995/6) based on review of the expectations against the
standard, this patch cleans up expectations for stdlib.h and
string.h. Tested x86_64; no new XFAILs needed.
* conform/data/stdlib.h-data [POSIX] (stddef.h): Do not allow
header inclusion.
[POSIX] (limits.h): Likewise.
[POSIX] (math.h): Likewise.
[POSIX] (sys/wait.h): Likewise.
* conform/data/string.h-data [POSIX || UNIX98] (strtok_r): Require
function.
[POSIX] (stddef.h): Do not allow header inclusion.
lll_unlock() will be called again if it goes to "wake_all" in
pthread_cond_broadcast(). This may make another thread which is
waiting for lock in pthread_cond_timedwait() unlock. So there are
more than one threads get the lock, it will break the shared data.
It's introduced by commit 8313cb997d2d("FUTEX_*_REQUEUE_PI support for
non-x86 code")