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linux: Only use 64-bit syscall if required for timerfd_settime

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For !__ASSUME_TIME64_SYSCALLS there is no need to issue a 64-bit syscall
if the provided timeout fits in a 32-bit one.  The 64-bit usage should
be rare since the timeout is a relative one.

Checked on i686-linux-gnu on a 4.15 kernel and on a 5.11 kernel
(with and without --enable-kernel=5.1) and on x86_64-linux-gnu.

Reviewed-by: Lukasz Majewski <lukma@denx.de>
This commit is contained in:
Adhemerval Zanella
2021-06-15 22:56:12 -03:00
parent eef7913c2f
commit 2c0982eb93
3 changed files with 48 additions and 13 deletions
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25
sysdeps/unix/sysv/linux/timerfd_settime.c
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@ -29,31 +29,34 @@ __timerfd_settime64 (int fd, int flags, const struct __itimerspec64 *value,
#ifndef __NR_timerfd_settime64
# define __NR_timerfd_settime64 __NR_timerfd_settime
#endif
int ret = INLINE_SYSCALL_CALL (timerfd_settime64, fd, flags, value, ovalue);
#ifndef __ASSUME_TIME64_SYSCALLS
if (ret == 0 || errno != ENOSYS)
return ret;
if (! in_time_t_range ((value->it_value).tv_sec)
|| ! in_time_t_range ((value->it_interval).tv_sec))
#ifdef __ASSUME_TIME64_SYSCALLS
return INLINE_SYSCALL_CALL (timerfd_settime64, fd, flags, value, ovalue);
#else
bool need_time64 = !in_time_t_range (value->it_value.tv_sec)
|| !in_time_t_range (value->it_interval.tv_sec);
if (need_time64)
{
int r = INLINE_SYSCALL_CALL (timerfd_settime64, fd, flags, value,
ovalue);
if (r == 0 || errno != ENOSYS)
return r;
__set_errno (EOVERFLOW);
return -1;
return r;
}
struct itimerspec its32, oits32;
its32.it_interval = valid_timespec64_to_timespec (value->it_interval);
its32.it_value = valid_timespec64_to_timespec (value->it_value);
ret = INLINE_SYSCALL_CALL (timerfd_settime, fd, flags,
&its32, ovalue ? &oits32 : NULL);
int ret = INLINE_SYSCALL_CALL (timerfd_settime, fd, flags,
&its32, ovalue != NULL ? &oits32 : NULL);
if (ret == 0 && ovalue != NULL)
{
ovalue->it_interval = valid_timespec_to_timespec64 (oits32.it_interval);
ovalue->it_value = valid_timespec_to_timespec64 (oits32.it_value);
}
#endif
return ret;
#endif
}
#if __TIMESIZE != 64