This patch reduces duplication between different architectures'
kernel-features.h files by making the architecture-independent file
define various macros unconditionally (instead of only for a
particular list of architectures), with the architecture-specific
files then undefining the macros if necessary.
Specifically, __ASSUME_O_CLOEXEC (O_CLOEXEC flag to open) and
__ASSUME_SOCK_CLOEXEC (SOCK_NONBLOCK and SOCK_CLOEXEC flags to socket)
are supported on all architectures as of 2.6.32 or the minimum kernel
version for the architecture if later. For __ASSUME_IN_NONBLOCK,
__ASSUME_PIPE2, __ASSUME_EVENTFD2, __ASSUME_SIGNALFD4 and
__ASSUME_DUP3, the relevant syscalls were added for alpha in 2.6.33
but otherwise the features are available as of 2.6.32. For
__ASSUME_UTIMES, support is everywhere in 2.6.32 except for
asm-generic architectures and hppa.
Although those were the main cases of duplication among
kernel-features.h files, some other cases of unnecessary definitions
were also cleaned up: the hppa file defined various macros that were
either no longer used at all, or defined by the main file by default
anyway, the ia64 file had duplicative definitions of __ASSUME_PSELECT
and __ASSUME_PPOLL, while mips had such a definition of
__ASSUME_IPC64.
Really, rather than being defined in the main file then undefined for
asm-generic architectures, __ASSUME_UTIMES should become an
hppa-specific macro. Given that __ASSUME_ATFCTS and
__ASSUME_UTIMENSAT are now always true, the only live __ASSUME_UTIMES
conditional is in sysdeps/unix/sysv/linux/utimes.c, which is not used
for asm-generic architectures. I think the desired state would be an
hppa-specific file (that includes sysdeps/unix/sysv/linux/utimes.c if
__ASSUME_UTIMES, and otherwise has fallback code), with the fallback
code being removed from the main utimes.c. But I think that's most
reasonably a separate cleanup once __ASSUME_ATFCTS and
__ASSUME_UTIMESAT have both had conditional code cleaned up.
Given this patch, I think it's straightforward to move non-ex-ports
architectures to having their own kernel-features.h files, like
ex-ports architectures, rather than conditionals in the main file
(i.e., such a move won't require the architecture-specific file to
contain anything that isn't genuinely architecture-specific), and
would encourage architecture maintainers to do so.
Tested x86_64 that the installed shared libraries are unchanged by
this patch. Note that on some architectures this *will* cause
__ASSUME_* macros to be defined in cases where they weren't previously
but should have been (but this is just optimization, not a fix to a
user-visible bug, so doesn't need a bug report in Bugzilla).
* sysdeps/unix/sysv/linux/kernel-features.h (__ASSUME_UTIMES):
Define unconditionally.
(__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/aarch64/kernel-features.h
(__ASSUME_DUP3): Do not define.
(__ASSUME_EVENTFD2): Likewise.
(__ASSUME_IN_NONBLOCK): Likewise.
(__ASSUME_O_CLOEXEC): Likewise.
(__ASSUME_PIPE2): Likewise.
(__ASSUME_SIGNALFD4): Likewise.
(__ASSUME_SOCK_CLOEXEC): Likewise.
(__ASSUME_UTIMES): Undefine.
* sysdeps/unix/sysv/linux/alpha/kernel-features.h
(__ASSUME_UTIMES): Do not define.
(__ASSUME_O_CLOEXEC): Likewise.
(__ASSUME_SOCK_CLOEXEC): Likewise.
(__ASSUME_IN_NONBLOCK): Undefine if [__LINUX_KERNEL_VERSION <
0x020621] instead of defining if [__LINUX_KERNEL_VERSION >=
0x020621].
(__ASSUME_PIPE2): Likewise.
(__ASSUME_EVENTFD2): Likewise.
(__ASSUME_SIGNALFD4): Likewise.
[__LINUX_KERNEL_VERSION < 0x020621] (__ASSUME_DUP3): Undefine.
* sysdeps/unix/sysv/linux/arm/kernel-features.h (__ASSUME_UTIMES):
Do not define.
(__ASSUME_EVENTFD2): Likewise.
(__ASSUME_SIGNALFD4): Likewise.
* sysdeps/unix/sysv/linux/hppa/kernel-features.h
(__ASSUME_32BITUIDS): Likewise.
(__ASSUME_TRUNCATE64_SYSCALL): Likewise.
(__ASSUME_IPC64): Likewise.
(__ASSUME_ST_INO_64_BIT): Likewise.
(__ASSUME_GETDENTS64_SYSCALL): Likewise.
[__LINUX_KERNEL_VERSION < 0x030e00] (__ASSUME_UTIMES): Undefine.
* sysdeps/unix/sysv/linux/ia64/kernel-features.h
(__ASSUME_UTIMES): Do not define.
(__ASSUME_PSELECT): Likewise.
(__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_UTIMES): 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/microblaze/kernel-features.h
(__ASSUME_UTIMES): 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/mips/kernel-features.h (__ASSUME_IPC64):
Likewise.
(__ASSUME_UTIMES): Likewise.
(__ASSUME_EVENTFD2): Likewise.
(__ASSUME_SIGNALFD4): Likewise.
* sysdeps/unix/sysv/linux/tile/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.
(__ASSUME_UTIMES): Undefine.
This patch cleans up some symbol versioning code in the ARM port that
exists only as relics of the old-ABI port, which was removed some time
ago.
The minimum symbol version in the ARM port is GLIBC_2.4 (the version
where the EABI port was introduced). Thus, any SHLIB_COMPAT
conditionals where the later version is 2.4 or later are obsolete and
can be removed. In addition, there is no need to set symbol versions
before 2.4 explicitly if the symbols would have a version of 2.4 by
default anyway. This includes most of the entries in
sysdeps/unix/sysv/linux/arm/Versions: those for GLIBC_2.0 are for
libgcc unwind functions that aren't actually in ARM EABI glibc at all,
while those for GLIBC_2.2 and GLIBC_2.3.3 are for functions which for
the old-ABI port may have had versions different from the
architecture-independent default, but where for EABI the default
suffices (both the default and the version in that file map to 2.4, so
the entries in that file do nothing). The GLIBC_2.1 entries are
needed (architecture-specific functions), but it seems less confusing
for those to say GLIBC_2.4, as the actual version those symbols in
fact have.
Various cases in the <fenv.h> functions where a function is defined as
__fe* with an fe* versioned alias are cleaned up just to define fe*
directly, as done e.g. on AArch64. If in future we actually need an
__fe* name for use from C90 functions in libm as discussed recently,
of course we can add one on all architectures and make the fe* name
into a weak alias for that particular function, but for now the __fe*
names aren't needed.
In the case of posix_fadvise64, the __posix_fadvise64_l64 name and
posix_fadvise64 alias are kept as __posix_fadvise64_l64 is used in
posix_fadvise. (For that to be a namespace-clean use, posix_fadvise64
needs to be a *weak* alias not a strong one as at present, but that's
an independent preexisting bug.)
(There remain references to GLIBC_2_2 in
sysdeps/unix/sysv/linux/arm/{msgctl.c,semctl.c,shmctl.c}. As those
files are used by alpha which has a genuine 2.2 version for those
functions, I think those references need to stay as-is.)
Tested that the disassembly of installed shared libraries is unchanged
by this patch (though function names shown in disassembly change to no
longer have @@GLIBC_2.4, now those functions get versioned only by the
version map and not redundantly at assembler time) and that the ABI
tests pass.
* sysdeps/arm/fclrexcpt.c (__feclearexcept): Rename to
feclearexcept. Remove symbol versioning code.
* sysdeps/arm/fegetenv.c (__fegetenv): Rename to fegetenv. Remove
symbol versioning code.
* sysdeps/arm/fesetenv.c (__fesetenv): Rename to fesetenv. Remove
symbol versioning code.
* sysdeps/arm/feupdateenv.c (__feupdateenv): Rename to
feupdateenv. Remove symbol versioning code.
* sysdeps/arm/fgetexcptflg.c (__fegetexceptflag): Rename to
fegetexceptflag. Remove symbol versioning code.
* sysdeps/arm/fsetexcptflg.c (__fesetexceptflag): Rename to
fesetexceptflag. Remove symbol versioning code.
* sysdeps/unix/sysv/linux/arm/Versions (libc): Remove GLIBC_2.0,
GLIBC_2.2 and GLIBC_2.3.3 entries. Change GLIBC_2.1 to GLIBC_2.4.
* sysdeps/unix/sysv/linux/arm/posix_fadvise64.c
(__posix_fadvise64_l32): Remove prototype.
[SHLIB_COMPAT(libc, GLIBC_2_2, GLIBC_2_3_3)]: Remove conditional
code.
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.
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 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.
The current implementation of setcontext uses rt_sigreturn to restore
the contents of registers. This contrasts with the way most other
architectures implement setcontext:
powerpc64, mips, tile:
Call rt_sigreturn if context was created by a call to a signal handler,
otherwise restore in user code.
powerpc32:
Call swapcontext system call and don't call sigreturn or rt_sigreturn.
x86_64, sparc, hppa, sh, ia64, m68k, s390, arm:
Only support restoring "synchronous" contexts, that is contexts
created by getcontext, and restoring in user code and don't call
sigreturn or rt_sigreturn.
alpha:
Call sigreturn (but not rt_sigreturn) in all cases to do the restore.
The text of the setcontext manpage suggests that the requirement to be
able to restore a signal handler created context has been dropped from
SUSv2:
If the context was obtained by a call to a signal handler, then old
standard text says that "program execution continues with the program
instruction following the instruction interrupted by the signal".
However, this sentence was removed in SUSv2, and the present verdict
is "the result is unspecified".
Implementing setcontext by calling rt_sigreturn unconditionally causes
problems when used with sigaltstack as in BZ #16629. On this basis it
seems that aarch64 is broken and that new ports should only support
restoring contexts created with getcontext and do not need to call
rt_sigreturn at all.
This patch re-implements the aarch64 setcontext function to restore
the context in user code in a similar manner to x86_64 and other ports.
ChangeLog:
2014-04-17 Will Newton <will.newton@linaro.org>
[BZ #16629]
* sysdeps/unix/sysv/linux/aarch64/setcontext.S (__setcontext):
Re-implement to restore registers in user code and avoid
rt_sigreturn system call.
[BZ #15215] This unifies various pthread_once architecture-specific
implementations which were using the same algorithm with slightly different
implementations. It also adds missing memory barriers that are required for
correctness.
This patch moves the __PTHREAD_SPINS definition to arch specific header
since pthread_mutex_t layout is also arch specific. This leads to no
need to defining __PTHREAD_MUTEX_HAVE_ELISION and thus removing of the
undefined compiler warning.
This patch makes the configure adds -D_CALL_ELF=1 when compiler does
not define _CALL_ELF (versions before powerpc64le support). It cleans
up compiler warnings on old compiler where _CALL_ELF is not defined
on powerpc64(be) builds.
It does by add a new config.make variable for configure-deduced
CPPFLAGS and accumulate into that (confix-extra-cppflags). It also
generalizes libc_extra_cflags so it accumulates in sysdeps configure
fragmenets.
This patch continues fixing __ASSUME_* issues in preparation for
moving to a 2.6.32 minimum kernel version by addressing assumptions on
robust mutex and PI futex support availability. Those assumptions are
bug 9894, but to be clear this patch does not address all the issues
from that bug about wrong version assumptions, only those still
applicable for --enable-kernel=2.6.32 or later (with the expectation
that the move to that minimum kernel will obsolete the other parts of
the bug). The patch is independent of
<https://sourceware.org/ml/libc-alpha/2014-03/msg00585.html>, my other
pending-review patch preparing for the kernel version change; the two
together complete all the changes I believe are needed in preparation
regarding any macro in sysdeps/unix/sysv/linux/kernel-features.h that
would be affected by such a change. (I have not checked the
correctness of macros whose conditions are unaffected by such a
change, or macros only defined in other kernel-features.h files.)
As discussed in that bug, robust mutexes and PI futexes need
futex_atomic_cmpxchg_inatomic to be implemented, in addition to
certain syscalls needed for robust mutexes (and
architecture-independent kernel pieces for all the features in
question). That is, as I understand it, they need
futex_atomic_cmpxchg_inatomic to *work* (not return an ENOSYS error).
The issues identified in my analysis relate to ARM, M68K, MicroBlaze,
MIPS and SPARC.
On ARM, whether futex_atomic_cmpxchg_inatomic works depends on the
kernel configuration. As of 3.13, the condition for *not* working is
CONFIG_CPU_USE_DOMAINS && CONFIG_SMP. As of 2.6.32 it was simply
CONFIG_SMP that meant the feature was not implemented. I don't know
if there are any circumstances in which we can say "we can assume a
userspace glibc binary built with these options will never run on a
kernel with the problematic configuration", but at least for now I'm
just undefining the relevant __ASSUME_* macros for ARM.
On M68K, two of the three macros are undefined for kernels before
3.10, but as far as I can see __ASSUME_FUTEX_LOCK_PI is in the same
group needing futex_atomic_cmpxchg_inatomic support and so should be
undefined as well.
On MicroBlaze the required support was added in 2.6.33.
On MIPS, the support depends on cpu_has_llsc in the kernel - that is,
actual hardware LL/SC support (GCC and glibc for MIPS GNU/Linux rely
on the instructions being supported in some way, but it may be kernel
emulation; futex_atomic_cmpxchg_inatomic doesn't work with that
emulation). The same condition as in GCC for indicating LL/SC support
may not be available is used for undefining the macros in glibc,
__mips == 1 || defined _MIPS_ARCH_R5900. (Maybe we could in fact
desupport MIPS processors without the hardware support in glibc.)
On SPARC, 32-bit kernels don't support futex_atomic_cmpxchg_inatomic;
__arch64__ || __sparc_v9__ is used as the condition for binaries that
won't run on 32-bit kernels.
This patch is not tested beyond the sanity check of an x86_64 build.
[BZ #9894]
* sysdeps/unix/sysv/linux/kernel-features.h
[__sparc__ && !__arch64__ && !__sparc_v9__]
(__ASSUME_SET_ROBUST_LIST): Do not define.
[__sparc__ && !__arch64__ && !__sparc_v9__]
(__ASSUME_FUTEX_LOCK_PI): Likewise.
[__sparc__ && !__arch64__ && !__sparc_v9__] (__ASSUME_REQUEUE_PI):
Likewise.
* sysdeps/unix/sysv/linux/arm/kernel-features.h
(__ASSUME_FUTEX_LOCK_PI): Undefine.
(__ASSUME_REQUEUE_PI): Likewise.
(__ASSUME_SET_ROBUST_LIST): Likewise.
* sysdeps/unix/sysv/linux/m68k/kernel-features.h
[__LINUX_KERNEL_VERSION < 0x030a00] (__ASSUME_FUTEX_LOCK_PI):
Undefine.
* sysdeps/unix/sysv/linux/microblaze/kernel-features.h
[__LINUX_KERNEL_VERSION < 0x020621] (__ASSUME_FUTEX_LOCK_PI):
Likewise.
[__LINUX_KERNEL_VERSION < 0x020621] (__ASSUME_REQUEUE_PI):
Likewise.
[__LINUX_KERNEL_VERSION < 0x020621] (__ASSUME_SET_ROBUST_LIST):
Likewise.
* sysdeps/unix/sysv/linux/mips/kernel-features.h
[__mips == 1 || _MIPS_ARCH_R5900] (__ASSUME_FUTEX_LOCK_PI):
Undefine.
[__mips == 1 || _MIPS_ARCH_R5900] (__ASSUME_REQUEUE_PI): Likewise.
[__mips == 1 || _MIPS_ARCH_R5900] (__ASSUME_SET_ROBUST_LIST):
Likewise.
Continuing the fixes for __ASSUME_* issues in preparation for moving
to a 2.6.32 minimum kernel version, this *untested* patch fixes bug
16648, the definition of __ASSUME_ATFCTS meaning that the futimesat
syscall is assumed for all MicroBlaze kernels despite not being
present until 2.6.33.
__ASSUME_ATFCTS controls conditionals relating to a lot of different
syscalls in Linux-specific code (fstatat64 faccessat fchmodat fchownat
futimesat newfstatat linkat mkdirat openat readlinkat renameat
symlinkat unlinkat mknodat), where whether newfstatat fstatat64
futimesat are used depends on the architecture, as well as controlling
whether openat64_not_cancel_3 is expected to work in
sysdeps/posix/getcwd.c. The assumptions are all OK as of 2.6.32
except for this MicroBlaze case, and it's generally desirable to get
rid of as many of the __ASSUME_ATFCTS conditionals as possible, to
simplify the code (the fallbacks include potential unbounded dynamic
stack allocations). Thus, rather than the simplest approach of
undefining __ASSUME_ATFCTS for older kernels on MicroBlaze, this patch
takes the approach of using the linux-generic implementation of
futimesat for MicroBlaze kernels before 2.6.33 (all such kernels have
the utimensat syscall).
[BZ #16648]
* sysdeps/unix/sysv/linux/microblaze/kernel-features.h
[__LINUX_KERNEL_VERSION >= 0x020621] (__ASSUME_FUTIMESAT): Define.
* sysdeps/unix/sysv/linux/microblaze/futimesat.c: New file.
To reproduce:
# ip li add name dummy0 type dummy
# site_id=$(head -c6 /dev/urandom | od -tx2 -An | tr ' ' ':')
# for ((i = 0; i < 65536; i++)) do
> ip ad ad $(printf fd80$site_id::%04x $i)/128 dev dummy0
> done
# (ulimit -s 900; getent ahosts localhost)
# ip li de dummy0
This patch fixes -Wundef warnings related to the _ABI* macros on MIPS.
GCC predefines only the _ABI* macro related to the ABI actually in
use, meaning that a conditional such as "#if _MIPS_SIM == _ABI64" is
true only for the ABI in question (all the macros are nonzero), but
produces a -Wundef warning for the other ABIs. The normal approach to
using these macros is to include <sgidefs.h>, which ensures that all
three _ABI* macros are defined rather than just one; this patch does
so in the places that caused warnings (the bulk of the warnings
arising from <bits/wordsize.h>). Tested that the warnings are fixed.
* sysdeps/mips/bits/wordsize.h: Include <sgidefs.h>.
* sysdeps/unix/sysv/linux/mips/getrlimit64.c: Likewise.
* sysdeps/unix/sysv/linux/mips/setrlimit64.c: Likewise.
Reviewing (for all architectures, with a baseline kernel version of
2.6.32) the kernel support for features for which __ASSUME_* macros
would be affected by a move to 2.6.32 as minimum kernel version showed
up that __ASSUME_PREADV and __ASSUME_PWRITEV were wrongly defined for
MicroBlaze (despite the corresponding syscall table entries not being
wired up in the kernel) and Alpha for 2.6.30 and above (although the
support on Alpha was added in 2.6.33). This patch makes the
kernel-features.h files undefine those macros for appropriate
versions.
[BZ #16649]
* sysdeps/unix/sysv/linux/alpha/kernel-features.h
[__LINUX_KERNEL_VERSION < 0x020621] (__ASSUME_PREADV): Undefine.
[__LINUX_KERNEL_VERSION < 0x020621] (__ASSUME_PWRITEV): Likewise.
* sysdeps/unix/sysv/linux/microblaze/kernel-features.h
(__ASSUME_PREADV): Undefine.
(__ASSUME_PWRITEV): Likewise.
