In the glibc the gettimeofday can use vDSO (on power and x86 the
USE_IFUNC_GETTIMEOFDAY is defined), gettimeofday syscall or 'default'
___gettimeofday() from ./time/gettime.c (as a fallback).
In this patch the last function (___gettimeofday) has been refactored and
moved to ./sysdeps/unix/sysv/linux/gettimeofday.c to be Linux specific.
The new __gettimeofday64 explicit 64 bit function for getting 64 bit time from
the kernel (by internally calling __clock_gettime64) has been introduced.
Moreover, a 32 bit version - __gettimeofday has been refactored to internally
use __gettimeofday64.
The __gettimeofday is now supposed to be used on systems still supporting 32
bit time (__TIMESIZE != 64) - hence the necessary check for time_t potential
overflow and conversion of struct __timeval64 to 32 bit struct timespec.
The iFUNC vDSO direct call optimization has been removed from both i686 and
powerpc32 (USE_IFUNC_GETTIMEOFDAY is not defined for those architectures
anymore). The Linux kernel does not provide a y2038 safe implementation of
gettimeofday neither it plans to provide it in the future, clock_gettime64
should be used instead. Keeping support for this optimization would require
to handle another build permutation (!__ASSUME_TIME64_SYSCALLS &&
USE_IFUNC_GETTIMEOFDAY) which adds more complexity and has limited use
(since the idea is to eventually have a y2038 safe glibc build).
Build tests:
./src/scripts/build-many-glibcs.py glibcs
Run-time tests:
- Run specific tests on ARM/x86 32bit systems (qemu):
https://github.com/lmajewski/meta-y2038 and run tests:
https://github.com/lmajewski/y2038-tests/commits/master
Above tests were performed with Y2038 redirection applied as well as without
to test proper usage of both __gettimeofday64 and __gettimeofday.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
[Including some commit message improvement]
file_change_detection_for_stat partially initialize
struct file_change_detection in some cases, when the size member
alone determines the outcome of all comparisons. This results
in maybe-uninitialized compiler warnings in case of sufficiently
aggressive inlining.
Once the implementation is moved into a separate C file, this kind
of inlining is no longer possible, so the compiler warnings are gone.
Exporting functions and relying on symbol interposition from libc.so
makes the choice of implementation dependent on DT_NEEDED order, which
is not what some compiler drivers expect.
This commit replaces one magic mechanism (symbol interposition) with
another one (preprocessor-/compiler-based redirection). This makes
the hand-over from the minimal malloc to the full malloc more
explicit.
Removing the ABI symbols is backwards-compatible because libc.so is
always in scope, and the dynamic loader will find the malloc-related
symbols there since commit f0b2132b35
("ld.so: Support moving versioned symbols between sonames
[BZ #24741]").
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
elf/dl-minimal.c provides a definition of free, so the function
pointer is always non-null, even before the final relocation
of the loader.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
The code started out with bits form resolv/resolv_conf.c, but it
was enhanced to deal with directories and FIFOs in a more predictable
manner. A test case is included as well.
This will be used to implement the /etc/resolv.conf change detection.
This currently lives in a header file only. Once there are multiple
users, the implementations should be moved into C files.
This patch provides new __settimeofday64 explicit 64 bit function for setting
64 bit time in the kernel (by internally calling __clock_settime64).
Moreover, a 32 bit version - __settimeofday has been refactored to internally
use __settimeofday64.
The __settimeofday is now supposed to be used on systems still supporting 32
bit time (__TIMESIZE != 64) - hence the necessary conversion of struct
timeval to 64 bit struct __timespec64.
Internally the settimeofday uses __settimeofday64. This patch is necessary
for having architectures with __WORDSIZE == 32 Y2038 safe.
Build tests:
./src/scripts/build-many-glibcs.py glibcs
Run-time tests:
- Run specific tests on ARM/x86 32bit systems (qemu):
https://github.com/lmajewski/meta-y2038 and run tests:
https://github.com/lmajewski/y2038-tests/commits/master
Above tests were performed with Y2038 redirection applied as well as without
to test proper usage of both __settimeofday64 and __settimeofday.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Those functions allow easy conversion between Y2038 safe, glibc internal
struct __timeval64 and other time related data structures (like struct timeval
or struct __timespec64).
Build tests:
./src/scripts/build-many-glibcs.py glibcs
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This type is a glibc's "internal" type similar to struct timeval but
whose tv_sec field is a __time64_t rather than a time_t, which makes it
Y2038-proof. This struct is NOT supposed to be passed to the kernel -
instead it shall be converted to struct __timespec64 and clock_[sg]ettime
syscalls shall be used (which are now Y2038 safe).
Build tests:
./src/scripts/build-many-glibcs.py glibcs
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This patch provides new instance of Linux specific timespec_get.c file placed
in ./sysdeps/unix/sysv/linux/.
When compared to this file version from ./time directory, it provides
__timespec_get64 explicit 64 bit function for getting 64 bit time in the
struct __timespec64 (for compilation using C11 standard).
Moreover, a 32 bit version - __timespec_get internally uses
__timespec_get64.
The __timespec_get is now supposed to be used on systems still supporting 32
bit time (__TIMESIZE != 64) - hence the necessary conversion to 32 bit struct
timespec.
Internally the timespec_get uses __clock_gettime64. This patch is necessary
for having architectures with __WORDSIZE == 32 Y2038 safe.
Build tests:
./src/scripts/build-many-glibcs.py glibcs
Run-time tests:
- Run specific tests on ARM/x86 32bit systems (qemu):
https://github.com/lmajewski/meta-y2038 and run tests:
https://github.com/lmajewski/y2038-tests/commits/master
Above tests were performed with Y2038 redirection applied as well as without
to test proper usage of both __timespec_get64 and __timespec_get.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The functions __timer_gettime64 and __timer_settime64 live in librt, not
libc. Use proper hidden aliases so that the callers do not need to set up
the PLT register.
Fixes commits cae1635a70 ("y2038: linux: Provide __timer_settime64
implementation") and 562cdc19c7 ("y2038: linux: Provide __timer_gettime64
implementation").
This patch replaces auto generated wrapper (as described in
sysdeps/unix/sysv/linux/syscalls.list) for sched_rr_get_interval with one which
adds extra support for reading 64 bit time values on machines with
__TIMESIZE != 64.
There is no functional change for architectures already supporting 64 bit
time ABI.
The sched_rr_get_interval declaration in ./include/sched.h is not followed by
corresponding libc_hidden_proto(), so it has been assumed that newly introduced
syscall wrapper doesn't require libc_hidden_def() (which has been added by
template used with auto generation script).
Moreover, the code for building sched_rr_gi.c file is already placed in
./posix/Makefiles, so there was no need to add it elsewhere.
Performed tests and validation are the same as for timer_gettime() conversion
(sysdeps/unix/sysv/linux/timer_gettime.c).
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This patch replaces auto generated wrapper (as described in
sysdeps/unix/sysv/linux/syscalls.list) for timerfd_settime with one which
adds extra support for reading and writing from Linux kernel 64 bit time
values on machines with __TIMESIZE != 64.
There is no functional change for archs already supporting 64 bit time ABI.
This patch is conceptually identical to timer_settime conversion already
done in sysdeps/unix/sysv/linux/timer_settime.c.
Please refer to corresponding commit message for detailed description of
introduced functions and the testing procedure.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
---
Changes for v4:
- Update date from 2019 to 2020
Changes for v3:
- Add missing libc_hidden_def()
Changes for v2:
- Remove "Contributed by" from the file header
- Remove early check for (fd < 0) in __timerfd_settime64 as the fd
correctness check is already done in Linux kernel
- Add single descriptive comment line to provide concise explanation
of the code
This patch replaces auto generated wrapper (as described in
sysdeps/unix/sysv/linux/syscalls.list) for timerfd_gettime with one which
adds extra support for reading 64 bit time values on machines with
__TIMESIZE != 64.
There is no functional change for architectures already supporting 64 bit
time ABI.
This patch is conceptually identical to timer_gettime conversion already
done in sysdeps/unix/sysv/linux/timer_gettime.c.
Please refer to corresponding commit message for detailed description of
introduced functions and the testing procedure.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
---
Changes for v4:
- Update date from 2019 to 2020
Changes for v3:
- Add missing libc_hidden_def()
Changes for v2:
- Remove "Contributed by" from the file header
- Remove early check for (fd < 0) in __timerfd_gettime64 as the fd
correctness check is already done in Linux kernel
- Add single descriptive comment line to provide concise explanation
of the code
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>
Commit a2e8aa0d9e ("Block signals during
the initial part of dlopen") was deemed necessary because of
read-modify-write operations like the one in add_dependency in
elf/dl-lookup.c. In the old code, we check for any kind of NODELETE
status and bail out:
/* Redo the NODELETE check, as when dl_load_lock wasn't held
yet this could have changed. */
if (map->l_nodelete != link_map_nodelete_inactive)
goto out;
And then set pending status (during relocation):
if (flags & DL_LOOKUP_FOR_RELOCATE)
map->l_nodelete = link_map_nodelete_pending;
else
map->l_nodelete = link_map_nodelete_active;
If a signal arrives during relocation and the signal handler, through
lazy binding, adds a global scope dependency on the same map, it will
set map->l_nodelete to link_map_nodelete_active. This will be
overwritten with link_map_nodelete_pending by the dlopen relocation
code.
To avoid such problems in relation to the l_nodelete member, this
commit introduces two flags for active NODELETE status (irrevocable)
and pending NODELETE status (revocable until activate_nodelete is
invoked). As a result, NODELETE processing in dlopen does not
introduce further reasons why lazy binding from signal handlers
is unsafe during dlopen, and a subsequent commit can remove signal
blocking from dlopen.
This does not address pre-existing issues (unrelated to the NODELETE
changes) which make lazy binding in a signal handler during dlopen
unsafe, such as the use of malloc in both cases.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
This patch adds the missing __libpthread_version_placeholder for
GLIBC_2.2.6 version from the nanosleep implementation move from
libpthread to libc (79a547b162).
It also fixes the wrong compat symbol definitions added by changing
back the version used on vfork check and remove the
__libpthread_version_placeholder added on some ABI (4f4bb489e0).
The __libpthread_version_placeholder is also refactored to make it
simpler to add new compat_symbols by adding a new macro
compat_symbol_unique which uses the compiler extension __COUNTER__
to generate unique strong alias to be used with compat_symbol.
Checked with a updated-abi on the all affected abis of the nanosleep
move.
Change-Id: I347a4dbdc931bb42b359456932dd1e17aa4d4078
This patch provides new __timer_settime64 explicit 64 bit function for setting
flags, interval and value of specified timer.
Moreover, a 32 bit version - __timer_settime has been refactored to internally
use __timer_settime64.
The __timer_settime is now supposed to be used on systems still supporting 32
bit time (__TIMESIZE != 64) - hence the necessary conversion to 64 bit struct
__timespec64 from struct timespec (and opposite when old_value pointer is
provided).
The new __timer_settime64 syscall available from Linux 5.1+ has been used, when
applicable.
The original INLINE_SYSCALL() macro has been replaced with
INLINE_SYSCALL_CALL() to avoid explicit passing the number of arguments.
Build tests:
- The code has been tested on x86_64/x86 (native compilation):
make PARALLELMFLAGS="-j8" && make check PARALLELMFLAGS="-j8" && \\
make xcheck PARALLELMFLAGS="-j8"
- The glibc has been build tested (make PARALLELMFLAGS="-j8") for
x86 (i386), x86_64-x32, and armv7
Run-time tests:
- Run specific tests on ARM/x86 32bit systems (qemu):
https://github.com/lmajewski/meta-y2038 and run tests:
https://github.com/lmajewski/y2038-tests/commits/master
- Use of cross-test-ssh.sh for ARM (armv7):
make PARALLELMFLAGS="-j8" test-wrapper='./cross-test-ssh.sh root@192.168.7.2' xcheck
Linux kernel, headers and minimal kernel version for glibc build test
matrix:
- Linux v5.1 (with timer_settime64) and glibc build with v5.1 as
minimal kernel version (--enable-kernel="5.1.0")
The __ASSUME_TIME64_SYSCALLS flag defined.
- Linux v5.1 and default minimal kernel version
The __ASSUME_TIME64_SYSCALLS not defined, but kernel supports timer_settime64
syscall.
- Linux v4.19 (no timer_settime64 support) with default minimal kernel version
for contemporary glibc (3.2.0)
This kernel doesn't support timer_settime64 syscall, so the fallback to
timer_settime is tested.
Above tests were performed with Y2038 redirection applied as well as without
(so the __TIMESIZE != 64 execution path is checked as well).
No regressions were observed.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This patch provides new __timer_gettime64 explicit 64 bit function for reading
status of specified timer. To be more precise - the remaining time and interval
set with timer_settime.
Moreover, a 32 bit version - __timer_gettime has been refactored to internally
use __timer_gettime64.
The __timer_gettime is now supposed to be used on systems still supporting 32
bit time (__TIMESIZE != 64) - hence the necessary conversion from 64 bit struct
__timespec64 to struct timespec.
The new __timer_gettime64 syscall available from Linux 5.1+ has been used, when
applicable.
The original INLINE_SYSCALL() macro has been replaced with
INLINE_SYSCALL_CALL() to avoid explicit passing the number of arguments.
Build tests:
- The code has been tested on x86_64/x86 (native compilation):
make PARALLELMFLAGS="-j8" && make check PARALLELMFLAGS="-j8" && \\
make xcheck PARALLELMFLAGS="-j8"
- The glibc has been build tested (make PARALLELMFLAGS="-j8") for
x86 (i386), x86_64-x32, and armv7
Run-time tests:
- Run specific tests on ARM/x86 32bit systems (qemu):
https://github.com/lmajewski/meta-y2038 and run tests:
https://github.com/lmajewski/y2038-tests/commits/master
- Use of cross-test-ssh.sh for ARM (armv7):
make PARALLELMFLAGS="-j8" test-wrapper='./cross-test-ssh.sh root@192.168.7.2' xcheck
Linux kernel, headers and minimal kernel version for glibc build test
matrix:
- Linux v5.1 (with timer_gettime64) and glibc build with v5.1 as
minimal kernel version (--enable-kernel="5.1.0")
The __ASSUME_TIME64_SYSCALLS flag defined.
- Linux v5.1 and default minimal kernel version
The __ASSUME_TIME64_SYSCALLS not defined, but kernel supports timer_gettime64
syscall.
- Linux v4.19 (no timer_gettime64 support) with default minimal kernel version
for contemporary glibc (3.2.0)
This kernel doesn't support timer_gettime64 syscall, so the fallback to
timer_gettime is tested.
Above tests were performed with Y2038 redirection applied as well as without
(so the __TIMESIZE != 64 execution path is checked as well).
No regressions were observed.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This change provides the glibc's internal struct itimerspec representation,
which is explicitly supporting 64 bit time (by using struct __timespec64).
Such representation is necessary to provide correct time after Y2038
(time_t overflow) on devices with __TIMESIZE == 32.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
With the clock_gettime64 call we prefer to use vDSO. There is no call
to clock_gettime64 on glibc with older headers and kernel 5.1+ if it
doesn't support vDSO.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Similarly to what has been done for printf-like functions, more
specifically to the internal implementation in __vfprintf_internal, this
patch extends __vstrfmon_l_internal to deal with long double values with
binary128 format (as a third format option and reusing the float128
implementation).
Tested for powerpc64le, powerpc64, x86_64, and with build-many-glibcs.
Reviewed-by: Paul E. Murphy <murphyp@linux.ibm.com>
ld.so symbols to be overriden by libc need to be extern to really get
overriden. __access happens to have never been exposed, putting it to
GLIBC_PRIVATE.
ld.so symbols to be overriden by libc need to be extern to really get
overriden. __getcwd happens to have never been exposed, putting it to
GLIBC_PRIVATE.
This introduces a “pending NODELETE” state in the link map, which is
flipped to the persistent NODELETE state late in dlopen, via
activate_nodelete. During initial relocation, symbol binding
records pending NODELETE state only. dlclose ignores pending NODELETE
state. Taken together, this results that a partially completed dlopen
is rolled back completely because new NODELETE mappings are unloaded.
Tested on x86_64-linux-gnu and i386-linux-gnu.
Change-Id: Ib2a3d86af6f92d75baca65431d74783ee0dbc292
When the commit
commit 03992356e6
Author: Zack Weinberg <zackw@panix.com>
Date: Sat Feb 10 11:58:35 2018 -0500
Use C99-compliant scanf under _GNU_SOURCE with modern compilers.
added the DEPRECATED_SCANF macro to select when redirections of *scanf
functions to their ISO C99 compliant versions should happen, it
accidentally missed doing it for vfwscanf, vwscanf, and vswscanf.
Tested for powerpc64le and with build-many-glibcs (i686-linux-gnu and
nios2-linux-gnu are failing with current master, and with this patch,
but I didn't see a regression).
Change-Id: I706b344a3fb50be017cdab9251d9da18a3ba8c60
issignalingf is a very small function used in some areas where
better performance (and smaller code) might be helpful.
Create inline implementation for issignalingf.
Reviewed-by: Joseph Myers <joseph@codesourcery.com>
l_audit ends up as an internal array with _rtld_global, and GCC 10
warns about this.
This commit does not change the layout of _rtld_global, so it is
suitable for backporting. Future changes could allocate more of the
audit state dynamically and remove it from always-allocated data
structures, to optimize the common case of inactive auditing.
Change-Id: Ic911100730f9124d4ea977ead8e13cee64b84d45
This patch provides new __ppoll64 explicit 64 bit function for handling polling
events (with struct timespec specified timeout) for a set of file descriptors.
Moreover, a 32 bit version - __ppoll has been refactored to internally use
__ppoll64.
The __ppoll is now supposed to be used on systems still supporting 32 bit time
(__TIMESIZE != 64) - hence the necessary conversion to 64 bit struct
__timespec64.
The new ppoll_time64 syscall available from Linux 5.1+ has been used, when
applicable.
The Linux kernel checks if passed tv_nsec value overflows, so there is no need
to repeat it in the glibc.
When ppoll syscall on systems supporting 32 bit time ABI is used, the check is
performed if passed data (which may have 64 bit tv_sec) fits into 32 bit range.
Build tests:
- The code has been tested on x86_64/x86 (native compilation):
make PARALLELMFLAGS="-j8" && make check PARALLELMFLAGS="-j8" && \\
make xcheck PARALLELMFLAGS="-j8"
- The glibc has been build tested (make PARALLELMFLAGS="-j8") for
x86 (i386), x86_64-x32, and armv7
Run-time tests:
- Run specific tests on ARM/x86 32bit systems (qemu):
https://github.com/lmajewski/meta-y2038 and run tests:
https://github.com/lmajewski/y2038-tests/commits/master
- Use of cross-test-ssh.sh for ARM (armv7):
make PARALLELMFLAGS="-j8" test-wrapper='./cross-test-ssh.sh root@192.168.7.2' xcheck
Linux kernel, headers and minimal kernel version for glibc build test
matrix:
- Linux v5.1 (with ppoll_time64) and glibc build with v5.1 as
minimal kernel version (--enable-kernel="5.1.0")
The __ASSUME_TIME64_SYSCALLS flag defined.
- Linux v5.1 and default minimal kernel version
The __ASSUME_TIME64_SYSCALLS not defined, but kernel supports ppoll_time64
syscall.
- Linux v4.19 (no ppoll_time64 support) with default minimal kernel version for
contemporary glibc
This kernel doesn't support ppoll_time64 syscall, so the fallback to ppoll is
tested.
Above tests were performed with Y2038 redirection applied as well as without
(so the __TIMESIZE != 64 execution path is checked as well).
No regressions were observed.
The clock_nanosleep syscall is not supported on newer 32-bit platforms (such
as RV32). To fix this issue let's use clock_nanosleep_time64 if it is
avaliable.
The generic version is straightforward. For Hurd, its nanosleep
implementation is moved to clock_nanosleep with adjustments from
generic unix implementation.
The generic clock_nanosleep unix version is also removed since
it calls nanosleep.
Checked on x86_64-linux-gnu and powerpc64le-linux-gnu.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
This patch provides new __futimens64 explicit 64 bit function for
setting access and modification time of file (by using its file descriptor).
Moreover, a 32 bit version - __futimens has been refactored to internally use
__futimens64.
The __futimens is now supposed to be used on systems still supporting
32 bit time (__TIMESIZE != 64) - hence the necessary conversions to 64 bit
struct __timespec64.
When pointer to struct __timespec64 is NULL - the file access and modification
time is set to the current one (by the kernel) and no conversions from struct
timespec to __timespec64 are performed.
The __futimens64 reuses __utimensat64_helper defined for __utimensat64.
The test procedure for __futimens64 is the same as for __utimensat64 conversion
patch.
This patch provides new __utimensat64 explicit 64 bit function for
setting access and modification time of a file. Moreover, a 32 bit version
- __utimensat has been refactored to internally use __utimensat64.
The __utimensat is now supposed to be used on systems still supporting
32 bit time (__TIMESIZE != 64) - hence the necessary conversions to 64 bit
struct __timespec64.
When pointer to struct __timespec64 is NULL - the file access and modification
time is set to the current one and no conversions from struct timespec to
__timespec64 are performed.
The new utimensat_time64 syscall available from Linux 5.1+ has been used,
when applicable.
The new helper function - __utimensat64_helper - has been introduced to
facilitate code re-usage on function providing futimens syscall handling.
The Linux kernel checks if passed tv_nsec value overflows, so there is no
need to repeat it in glibc.
When utimensat syscall on systems supporting 32 bit time ABI is used,
the check is performed if passed data (which may have 64 bit tv_sec) fits
into 32 bit range.
Build tests:
- The code has been tested on x86_64/x86 (native compilation):
make PARALLELMFLAGS="-j8" && make xcheck PARALLELMFLAGS="-j8"
- The glibc has been build tested (make PARALLELMFLAGS="-j8") for
x86 (i386), x86_64-x32, and armv7
Run-time tests:
- Run specific tests on ARM/x86 32bit systems (qemu):
https://github.com/lmajewski/meta-y2038 and run tests:
https://github.com/lmajewski/y2038-tests/commits/master
- Use of cross-test-ssh.sh for ARM (armv7):
make PARALLELMFLAGS="-j8" test-wrapper='./cross-test-ssh.sh root@192.168.7.2' xcheck
Linux kernel, headers and minimal kernel version for glibc build test
matrix:
- Linux v5.1 (with utimensat_time64) and glibc build with v5.1 as
minimal kernel version (--enable-kernel="5.1.0")
The __ASSUME_TIME64_SYSCALLS flag defined.
- Linux v5.1 and default minimal kernel version
The __ASSUME_TIME64_SYSCALLS not defined, but kernel supports utimensat_time64
syscall.
- Linux v4.19 (no utimensat_time64 support) with default minimal kernel
version for contemporary glibc
This kernel doesn't support utimensat_time64 syscall, so the fallback
to utimensat is tested.
The above tests were performed with Y2038 redirection applied as well as
without (so the __TIMESIZE != 64 execution path is checked as well).
No regressions were observed.
Also make the public prototype of gettimeofday declare its second
argument with type "void *" unconditionally, consistent with POSIX.
It is also consistent with POSIX.
Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc64le-linux-gnu,
powerpc64-linux-gnu, powerpc-linux-gnu, and aarch64-linux-gnu.
Co-authored-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Lukasz Majewski <lukma@denx.de>
Consolidate generic gettimeofday implementation to use clock_gettime.
Linux ports that still provide gettimeofday through vDSO are not
changed.
Remove sysdeps/unix/clock_gettime.c, which implemented clock_gettime
using gettimeofday; new OS ports must provide a real implementation of
clock_gettime.
Rename sysdeps/mach/gettimeofday.c to sysdeps/mach/clock_gettime.c and
convert into an implementation of clock_gettime. It only supports
CLOCK_REALTIME; Mach does not appear to have any support for monotonic
clocks. It uses __host_get_time, which provides at best microsecond
resolution. Hurd is currently using sysdeps/posix/clock_getres.c for
clock_getres; its output for CLOCK_REALTIME is based on
sysconf (_SC_CLK_TCK), and I do not know whether that gives the
correct result.
Unlike settimeofday, there are no known uses of gettimeofday's
vestigial "get time zone" feature that are not bugs. (The per-process
timezone support in localtime and friends is unrelated, and the
programs that set the kernel's offset between the hardware clock and
UTC do not need to read it back.) Therefore, this feature is dummied
out. Henceforth, if gettimeofday's "struct timezone" argument is not
NULL, it will write zeroes to both fields. Any program that is
actually looking at this data will thus think it is running in UTC,
which is probably more correct than whatever it was doing before.
[__]gettimeofday no longer has any internal callers, so we can now
remove its internal prototype and PLT bypass aliases. The
__gettimeofday@GLIBC_2.0 export remains, in case it is used by any
third-party code.
It also allows to simplify the arch-specific implementation on x86 and
powerpc to remove the hack to disable the internal route to non iFUNC
variant for internal symbol.
This patch also fixes a missing optimization on aarch64, powerpc, and
x86 where the code used on static build do not use the vDSO.
Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc64le-linux-gnu,
powerpc64-linux-gnu, powerpc-linux-gnu, and aarch64-linux-gnu.
Co-authored-by: Zack Weinberg <zackw@panix.com>
Reviewed-by: Lukasz Majewski <lukma@denx.de>
As for gettimeofday, time will be implemented based on clock_gettime
on all platforms and internal code should use clock_gettime
directly. In addition to removing a layer of indirection, this will
allow us to remove the PLT-bypass gunk for gettimeofday.
The changed code always assumes __clock_gettime (CLOCK_REALTIME)
or __clock_gettime (CLOCK_REALTIME_COARSE) (for Linux case) cannot
fail, using the same rationale for gettimeofday change. And internal
helper was added (time_now).
Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc64le-linux-gnu,
powerpc64-linux-gnu, and powerpc-linux-gnu.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
Unconditionally, on all ports, use clock_settime to implement
settimeofday. Remove sysdeps/unix/clock_settime.c, which implemented
clock_settime by calling settimeofday; new OS ports must henceforth
provide a real implementation of clock_settime.
Hurd had a real implementation of settimeofday but not of
clock_settime; this patch converts it into an implementation of
clock_settime. It only supports CLOCK_REALTIME and microsecond
resolution; Hurd/Mach does not appear to have any support for
finer-resolution clocks.
The vestigial "set time zone" feature of settimeofday complicates the
generic settimeofday implementation a little. The only remaining uses
of this feature that aren't just bugs, are using it to inform the
Linux kernel of the offset between the hardware clock and UTC, on
systems where the hardware clock doesn't run in UTC (usually because
of dual-booting with Windows). There currently isn't any other way to
do this. However, the callers that do this call settimeofday with
_only_ the timezone argument non-NULL. Therefore, glibc's new
behavior is: callers of settimeofday must supply one and only one of
the two arguments. If both arguments are non-NULL, or both arguments
are NULL, the call fails and sets errno to EINVAL.
When only the timeval argument is supplied, settimeofday calls
__clock_settime(CLOCK_REALTIME), same as stime.
When only the timezone argument is supplied, settimeofday calls a new
internal function called __settimezone. On Linux, only, this function
will pass the timezone structure to the settimeofday system call. On
all other operating systems, and on Linux architectures that don't
define __NR_settimeofday, __settimezone is a stub that always sets
errno to ENOSYS and returns -1.
The settimeoday syscall is enabled on Linux by the flag
COMPAT_32BIT_TIME, which is an option to either 32-bits ABIs or COMPAT
builds (defined usually by 64-bit kernels that want to support 32-bit
ABIs, such as x86). The idea to future 64-bit time_t only ABIs
is to not provide settimeofday syscall.
The same semantics are implemented for Linux/Alpha's GLIBC_2.0 compat
symbol for settimeofday.
There are no longer any internal callers of __settimeofday, so the
internal prototype is removed.
Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc64le-linux-gnu,
powerpc64-linux-gnu, powerpc-linux-gnu, and aarch64-linux-gnu.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Lukasz Majewski <lukma@denx.de>
This patch provides new __clock_getres64 explicit 64 bit function for
getting the resolution (precision) of specified clock ID. Moreover, a
32 bit version - __clock_getres has been refactored to internally use
__clock_getres64.
The __clock_getres is now supposed to be used on systems still supporting
32 bit time (__TIMESIZE != 64) - hence the necessary conversion from 64 bit
struct __timespec64 to struct timespec.
The new clock_getres_time64 syscall available from Linux 5.1+ has been used,
when applicable.
On systems which are not supporting clock_getres_time64 (as their
clock_getres supports 64 bit time ABI) the vDSO syscall is attempted.
On the contrary the non-vDSO syscall is used for clock_getres_time64 as
up till now the kernel is not providing such interface.
No additional checks (i.e. if tv_nsec value overflow) are performed on
values returned via clock_getres{_time64} syscall, as it is assumed that
the Linux kernel will either return 0 and provide correct value or error.
The check for tv_sec being out of range on systems still supporting 32 bit
time (__TIMESIZE != 64) without Y2038 time support is also omitted as it is
_very_ unlikely that we would have a timer with resolution which exceeds 32
bit time_t range.
Build tests:
- The code has been tested on x86_64/x86 (native compilation):
make PARALLELMFLAGS="-j8" && make xcheck PARALLELMFLAGS="-j8"
- The glibc has been build tested (make PARALLELMFLAGS="-j8") for
x86 (i386), x86_64-x32, and armv7
Run-time tests:
- Run specific tests on ARM/x86 32bit systems (qemu):
https://github.com/lmajewski/meta-y2038 and run tests:
https://github.com/lmajewski/y2038-tests/commits/master
- Use of cross-test-ssh.sh for ARM (armv7):
make PARALLELMFLAGS="-j8" test-wrapper='./cross-test-ssh.sh root@192.168.7.2' xcheck
Linux kernel, headers and minimal kernel version for glibc build test
matrix:
- Linux v5.1 (with clock_getres_time64) and glibc build with v5.1 as
minimal kernel version (--enable-kernel="5.1.0")
The __ASSUME_TIME64_SYSCALLS flag defined.
- Linux v5.1 and default minimal kernel version
The __ASSUME_TIME64_SYSCALLS not defined, but kernel supports
clock_getres_time64 syscall.
- Linux v4.19 (no clock_getres_time64 support) with default minimal kernel
version for contemporary glibc
This kernel doesn't support clock_getres_time64 syscall, so the fallback
to clock_getres is tested.
The above tests were performed with Y2038 redirection applied as well as
without (so the __TIMESIZE != 64 execution path is checked as well).
No regressions were observed.
The valid_nanoseconds () static inline function has been introduced to
check if nanoseconds value is in the correct range - greater or equal to
zero and less than 1000000000.
The explicit #include <time.h> has been added to files where it was
missing.
The __syscall_slong_t type for ns has been used to avoid issues on x32.
Tested with:
- scripts/build-many-glibcs.py
- make PARALLELMFLAGS="-j12" && make PARALLELMFLAGS="-j12" xcheck on x86_64
Besides semop being a subset of semtimedop, new 32-bit architectures
on Linux are not expected to provide the syscall (only the 64-bit time
semtimedop).
Also, Linux 5.1 only wired-up semtimedop for the 64-bit architectures
that missed it (powerpc, s390, and sparc). This simplifies the code
to support it.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
This patch provides new __clock_settime64 explicit 64 bit function for
setting the time. Moreover, a 32 bit version - __clock_settime - has been
refactored to internally use __clock_settime64.
The __clock_settime is now supposed to be used on systems still supporting
32 bit time (__TIMESIZE != 64) - hence the necessary conversion to 64 bit
struct timespec.
The new clock_settime64 syscall available from Linux 5.1+ has been used,
when applicable.
In this patch the internal padding (tv_pad) of struct __timespec64 is
left untouched (on systems with __WORDSIZE == 32) as Linux kernel ignores
upper 32 bits of tv_nsec.
Build tests:
- The code has been tested on x86_64/x86 (native compilation):
make PARALLELMFLAGS="-j8" && make xcheck PARALLELMFLAGS="-j8"
- The glibc has been build tested (make PARALLELMFLAGS="-j8") for
x86 (i386), x86_64-x32, and armv7
Run-time tests:
- Run specific tests on ARM/x86 32bit systems (qemu):
https://github.com/lmajewski/meta-y2038 and run tests:
https://github.com/lmajewski/y2038-tests/commits/master
- Use of cross-test-ssh.sh for ARM (armv7):
make PARALLELMFLAGS="-j8" test-wrapper='./cross-test-ssh.sh root@192.168.7.2' xcheck
Linux kernel, headers and minimal kernel version for glibc build test
matrix:
- Linux v5.1 (with clock_settime64) and glibc build with v5.1 as minimal
kernel version (--enable-kernel="5.1.0")
The __ASSUME_TIME64_SYSCALLS flag defined.
- Linux v5.1 and default minimal kernel version
The __ASSUME_TIME64_SYSCALLS not defined, but kernel supports
__clock_settime64 syscalls.
- Linux v4.19 (no clock_settime64 support) with default minimal kernel
version for contemporary glibc
This kernel doesn't support __clock_settime64 syscalls, so the fallback
to clock_settime is tested.
The above tests were performed with Y2038 redirection applied as well as
without (so the __TIMESIZE != 64 execution path is checked as well).
No regressions were observed.
* include/time.h (__clock_settime64):
Add __clock_settime alias according to __TIMESIZE define
* sysdeps/unix/sysv/linux/clock_settime.c (__clock_settime):
Refactor this function to be used only on 32 bit machines as a wrapper
on __clock_settime64.
* sysdeps/unix/sysv/linux/clock_settime.c (__clock_settime64): Add
* sysdeps/unix/sysv/linux/clock_settime.c (__clock_settime64):
Use clock_settime64 kernel syscall (available from 5.1+ Linux)
