mirror of git://sourceware.org/git/glibc.git
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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| .. | ||
| alpha | ||
| arm | ||
| bsd | ||
| i386 | ||
| inet | ||
| mips | ||
| powerpc | ||
| sh | ||
| sysv/linux | ||
| x86_64 | ||
| Implies | ||
| Makefile | ||
| confstr.h | ||
| get_child_max.c | ||
| getlogin.c | ||
| getlogin_r.c | ||
| getpagesize.c | ||
| grantpt.c | ||
| ifreq.c | ||
| make-syscalls.sh | ||
| pt-fcntl.c | ||
| s-proto-cancel.S | ||
| s-proto.S | ||
| setxid.h | ||
| sockatmark.c | ||
| syscall-template.S | ||
| syscall.S | ||
| syscalls.list | ||
| sysdep.h | ||