glibc/sysdeps/unix/sysv/linux/clock_getres.c

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2005-04-27 Roland McGrath <roland@redhat.com> * sysdeps/unix/sysv/linux/kernel-posix-cpu-timers.h: New file. * sysdeps/unix/sysv/linux/clock_getcpuclockid.c: New file. * sysdeps/unix/sysv/linux/ia64/clock_getcpuclockid.c (HAS_CPUCLOCK): New macro. (clock_getcpuclockid): Function removed. #include the new linux file to define it instead. * sysdeps/unix/clock_gettime.c [HP_TIMING_AVAIL] (hp_timing_gettime): New function, broken out of ... (clock_gettime) [HP_TIMING_AVAIL]: ... here. Call it. (realtime_gettime): New function, broken out of ... (clock_gettime) [! HANDLED_REALTIME]: ... here. Call it. (clock_gettime) [SYSDEP_GETTIME_CPU]: Use new macro in default case. * sysdeps/unix/sysv/linux/clock_gettime.c (SYSCALL_GETTIME): New macro. (SYSDEP_GETTIME_CPUTIME): New macro. (SYSDEP_GETTIME): Use both. [! __ASSUME_POSIX_TIMERS] (maybe_syscall_gettime): New function, broken out of ... (SYSDEP_GETTIME): ... here. Use it. [__NR_clock_gettime] (HANDLED_CPUTIME): Define it. (SYSDEP_GETTIME_CPUTIME): New macro. Handle CPU timers by trying kernel support and falling back to hp-timing code. * sysdeps/posix/clock_getres.c [HP_TIMING_AVAIL] (hp_timing_getres): New function, broken out of ... (clock_getres) [HP_TIMING_AVAIL]: ... here. Call it. (realtime_getres): New function, broken out of ... (clock_getres) [! HANDLED_REALTIME]: ... here. Call it. (clock_getres) [SYSDEP_GETRES_CPU]: Use new macro in default case. * sysdeps/unix/sysv/linux/clock_getres.c (SYSCALL_GETRES): New macro. (SYSDEP_GETRES_CPUTIME): New macro. (SYSDEP_GETRES): Use both. [! __ASSUME_POSIX_TIMERS] (maybe_syscall_getres): New function, broken out of ... (SYSDEP_GETRES): ... here. Use it. [__NR_clock_getres] (HANDLED_CPUTIME): Define it. (SYSDEP_GETRES_CPUTIME): New macro. Handle CPU timers by trying kernel support and falling back to hp-timing code. * sysdeps/unix/sysv/linux/clock_nanosleep.c: Handle CLOCK_PROCESS_CPUTIME_ID and CLOCK_PROCESS_THREAD_ID specially, translating to the kernel clockid_t for our own process/thread clock.
2005-04-27 08:01:41 +00:00
/* clock_getres -- Get the resolution of a POSIX clockid_t. Linux version.
Copyright (C) 2003-2021 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
Prefer https to http for gnu.org and fsf.org URLs Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g ' \ $(find $(git ls-files) -prune -type f \ ! -name '*.po' \ ! -name 'ChangeLog*' \ ! -path COPYING ! -path COPYING.LIB \ ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \ ! -path manual/texinfo.tex ! -path scripts/config.guess \ ! -path scripts/config.sub ! -path scripts/install-sh \ ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \ ! -path INSTALL ! -path locale/programs/charmap-kw.h \ ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \ ! '(' -name configure \ -execdir test -f configure.ac -o -f configure.in ';' ')' \ ! '(' -name preconfigure \ -execdir test -f preconfigure.ac ';' ')' \ -print) and then by running 'make dist-prepare' to regenerate files built from the altered files, and then executing the following to cleanup: chmod a+x sysdeps/unix/sysv/linux/riscv/configure # Omit irrelevant whitespace and comment-only changes, # perhaps from a slightly-different Autoconf version. git checkout -f \ sysdeps/csky/configure \ sysdeps/hppa/configure \ sysdeps/riscv/configure \ sysdeps/unix/sysv/linux/csky/configure # Omit changes that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines git checkout -f \ sysdeps/powerpc/powerpc64/ppc-mcount.S \ sysdeps/unix/sysv/linux/s390/s390-64/syscall.S # Omit change that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
2019-09-07 05:40:42 +00:00
<https://www.gnu.org/licenses/>. */
#include <sysdep.h>
2005-04-27 Roland McGrath <roland@redhat.com> * sysdeps/unix/sysv/linux/kernel-posix-cpu-timers.h: New file. * sysdeps/unix/sysv/linux/clock_getcpuclockid.c: New file. * sysdeps/unix/sysv/linux/ia64/clock_getcpuclockid.c (HAS_CPUCLOCK): New macro. (clock_getcpuclockid): Function removed. #include the new linux file to define it instead. * sysdeps/unix/clock_gettime.c [HP_TIMING_AVAIL] (hp_timing_gettime): New function, broken out of ... (clock_gettime) [HP_TIMING_AVAIL]: ... here. Call it. (realtime_gettime): New function, broken out of ... (clock_gettime) [! HANDLED_REALTIME]: ... here. Call it. (clock_gettime) [SYSDEP_GETTIME_CPU]: Use new macro in default case. * sysdeps/unix/sysv/linux/clock_gettime.c (SYSCALL_GETTIME): New macro. (SYSDEP_GETTIME_CPUTIME): New macro. (SYSDEP_GETTIME): Use both. [! __ASSUME_POSIX_TIMERS] (maybe_syscall_gettime): New function, broken out of ... (SYSDEP_GETTIME): ... here. Use it. [__NR_clock_gettime] (HANDLED_CPUTIME): Define it. (SYSDEP_GETTIME_CPUTIME): New macro. Handle CPU timers by trying kernel support and falling back to hp-timing code. * sysdeps/posix/clock_getres.c [HP_TIMING_AVAIL] (hp_timing_getres): New function, broken out of ... (clock_getres) [HP_TIMING_AVAIL]: ... here. Call it. (realtime_getres): New function, broken out of ... (clock_getres) [! HANDLED_REALTIME]: ... here. Call it. (clock_getres) [SYSDEP_GETRES_CPU]: Use new macro in default case. * sysdeps/unix/sysv/linux/clock_getres.c (SYSCALL_GETRES): New macro. (SYSDEP_GETRES_CPUTIME): New macro. (SYSDEP_GETRES): Use both. [! __ASSUME_POSIX_TIMERS] (maybe_syscall_getres): New function, broken out of ... (SYSDEP_GETRES): ... here. Use it. [__NR_clock_getres] (HANDLED_CPUTIME): Define it. (SYSDEP_GETRES_CPUTIME): New macro. Handle CPU timers by trying kernel support and falling back to hp-timing code. * sysdeps/unix/sysv/linux/clock_nanosleep.c: Handle CLOCK_PROCESS_CPUTIME_ID and CLOCK_PROCESS_THREAD_ID specially, translating to the kernel clockid_t for our own process/thread clock.
2005-04-27 08:01:41 +00:00
#include <errno.h>
#include <time.h>
#include <sysdep-vdso.h>
#include <shlib-compat.h>
y2038: linux: Provide __clock_getres64 implementation 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.
2019-10-15 15:57:05 +00:00
#include <kernel-features.h>
/* Get resolution of clock. */
int
y2038: linux: Provide __clock_getres64 implementation 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.
2019-10-15 15:57:05 +00:00
__clock_getres64 (clockid_t clock_id, struct __timespec64 *res)
{
int r;
#ifndef __NR_clock_getres_time64
# define __NR_clock_getres_time64 __NR_clock_getres
#endif
#ifdef HAVE_CLOCK_GETRES64_VSYSCALL
r = INLINE_VSYSCALL (clock_getres_time64, 2, clock_id, res);
#else
r = INLINE_SYSCALL_CALL (clock_getres_time64, clock_id, res);
#endif
if (r == 0 || errno != ENOSYS)
return r;
#ifndef __ASSUME_TIME64_SYSCALLS
/* Fallback code that uses 32-bit support. */
y2038: linux: Provide __clock_getres64 implementation 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.
2019-10-15 15:57:05 +00:00
struct timespec ts32;
# ifdef HAVE_CLOCK_GETRES_VSYSCALL
r = INLINE_VSYSCALL (clock_getres, 2, clock_id, &ts32);
# else
r = INLINE_SYSCALL_CALL (clock_getres, clock_id, &ts32);
# endif
if (r == 0 && res != NULL)
y2038: linux: Provide __clock_getres64 implementation 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.
2019-10-15 15:57:05 +00:00
*res = valid_timespec_to_timespec64 (ts32);
#endif
return r;
y2038: linux: Provide __clock_getres64 implementation 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.
2019-10-15 15:57:05 +00:00
}
#if __TIMESIZE != 64
libc_hidden_def (__clock_getres64)
y2038: linux: Provide __clock_getres64 implementation 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.
2019-10-15 15:57:05 +00:00
int
__clock_getres (clockid_t clock_id, struct timespec *res)
{
struct __timespec64 ts64;
int retval;
retval = __clock_getres64 (clock_id, &ts64);
if (retval == 0 && res != NULL)
y2038: linux: Provide __clock_getres64 implementation 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.
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*res = valid_timespec64_to_timespec (ts64);
return retval;
}
y2038: linux: Provide __clock_getres64 implementation 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.
2019-10-15 15:57:05 +00:00
#endif
libc_hidden_def (__clock_getres)
versioned_symbol (libc, __clock_getres, clock_getres, GLIBC_2_17);
/* clock_getres moved to libc in version 2.17;
old binaries may expect the symbol version it had in librt. */
#if SHLIB_COMPAT (libc, GLIBC_2_2, GLIBC_2_17)
strong_alias (__clock_getres, __clock_getres_2);
compat_symbol (libc, __clock_getres_2, clock_getres, GLIBC_2_2);
#endif