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7455b70027
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] |
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| .. | ||
| bits | ||
| powerpc32 | ||
| powerpc64 | ||
| sys | ||
| configure | ||
| configure.ac | ||
| dl-auxv.h | ||
| dl-brk.S | ||
| dl-cache.h | ||
| dl-static.c | ||
| elision-conf.c | ||
| elision-conf.h | ||
| elision-lock.c | ||
| elision-timed.c | ||
| elision-trylock.c | ||
| elision-unlock.c | ||
| force-elision.h | ||
| get_timebase_freq.c | ||
| gettimeofday.c | ||
| htm.h | ||
| Implies | ||
| ioctl.c | ||
| ipc_priv.h | ||
| kernel_sigaction.h | ||
| kernel_termios.h | ||
| kernel-features.h | ||
| ldconfig.h | ||
| ldd-rewrite.sed | ||
| ldsodefs.h | ||
| libc-start.c | ||
| libc-start.h | ||
| libc-vdso.h | ||
| lowlevellock.h | ||
| Makefile | ||
| nldbl-abi.h | ||
| pt-longjmp.c | ||
| pthread_attr_setstack.c | ||
| pthread_attr_setstacksize.c | ||
| pthread_mutex_cond_lock.c | ||
| pthread_mutex_lock.c | ||
| pthread_mutex_timedlock.c | ||
| pthread_mutex_trylock.c | ||
| readelflib.c | ||
| rt-sysdep.c | ||
| sigcontextinfo.h | ||
| syscall.S | ||
| sysconf.c | ||
| sysdep.c | ||
| sysdep.h | ||
| test-gettimebasefreq-static.c | ||
| test-gettimebasefreq.c | ||
| test-powerpc-linux-sysconf.c | ||
| time.c | ||
| Versions | ||