glibc/sysdeps/unix/sysv/linux/x86
Lukasz Majewski 7455b70027 y2038: linux: Provide __gettimeofday64 implementation
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]
2020-02-18 23:55:47 +01:00
..
bits y2038: Define __suseconds64_t type to be used with struct __timeval64 2020-02-07 17:55:07 +01:00
include/asm x86/CET: Extend arch_prctl syscall for CET control 2018-07-24 12:23:17 -07:00
sys Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
arch-pkey.h Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
cpu-features.c linux: Remove INTERNAL_SYSCALL_DECL 2020-02-14 21:12:45 -03:00
dl-cet.h linux: Remove INTERNAL_SYSCALL_DECL 2020-02-14 21:12:45 -03:00
dl-sysdep.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
elision-conf.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
elision-conf.h Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
elision-lock.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
elision-timed.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
elision-trylock.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
elision-unlock.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
force-elision.h Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
gettimeofday.c y2038: linux: Provide __gettimeofday64 implementation 2020-02-18 23:55:47 +01:00
hle.h x86: Use RTM intrinsics in pthread mutex lock elision 2018-10-02 07:51:57 -07:00
Implies Consolidate pthreadtype.h placementConsolidate pthreadtype.h placement 2017-04-10 17:33:10 -03:00
jmp_buf-ssp.sym x86: Make a space in jmpbuf for shadow stack pointer 2017-11-30 04:58:01 -08:00
lowlevellock.h Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
Makefile elf: Move vDSO setup to rtld (BZ#24967) 2020-01-03 11:22:07 -03:00
pkey_get.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
pkey_set.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
pthread_mutex_cond_lock.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
pthread_mutex_lock.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
pthread_mutex_timedlock.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
pthread_mutex_trylock.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
setjmpP.h Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
sysconf.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
time.c linux: Consolidate time implementation 2020-01-03 11:22:04 -03:00
tst-cet-property-1.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
tst-cet-property-2.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
tst-cet-property-dep-2.S Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
tst-cet-setcontext-1.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
tst-saved_mask-1.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00