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linux: Only use 64-bit syscall if required for utimensat family

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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.

The large timeout are already tests by io/tst-utimensat-skeleton.c.

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
2021-06-16 10:43:57 -03:00
parent dafab287b4
commit b286eca5d4
1 changed files with 18 additions and 13 deletions
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31
sysdeps/unix/sysv/linux/utimensat.c
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@@ -31,34 +31,39 @@ __utimensat64_helper (int fd, const char *file,
#ifndef __NR_utimensat_time64 #ifndef __NR_utimensat_time64
# define __NR_utimensat_time64 __NR_utimensat # define __NR_utimensat_time64 __NR_utimensat
#endif #endif
int ret = INLINE_SYSCALL_CALL (utimensat_time64, fd, file, &tsp64[0], flags);
#ifndef __ASSUME_TIME64_SYSCALLS
if (ret == 0 || errno != ENOSYS)
return ret;
#ifdef __ASSUME_TIME64_SYSCALLS
return INLINE_SYSCALL_CALL (utimensat_time64, fd, file, &tsp64[0], flags);
#else
/* For UTIME_NOW and UTIME_OMIT the value of tv_sec field is ignored. */ /* For UTIME_NOW and UTIME_OMIT the value of tv_sec field is ignored. */
# define TS_VALID(ns) \ # define TS_SPECIAL(ts) \
((((ns).tv_nsec == UTIME_NOW || (ns).tv_nsec == UTIME_OMIT) \ ((ts).tv_nsec == UTIME_NOW || (ts).tv_nsec == UTIME_OMIT)
|| in_time_t_range ((ns).tv_sec)))
if (tsp64 != NULL bool need_time64 = tsp64 != NULL
&& (!TS_VALID (tsp64[0]) || !TS_VALID (tsp64[1]))) && ((!TS_SPECIAL (tsp64[0])
&& !in_time_t_range (tsp64[0].tv_sec))
|| (!TS_SPECIAL (tsp64[1])
&& !in_time_t_range (tsp64[1].tv_sec)));
if (need_time64)
{ {
int r = INLINE_SYSCALL_CALL (utimensat_time64, fd, file, &tsp64[0],
flags);
if (r == 0 || errno != ENOSYS)
return r;
__set_errno (EOVERFLOW); __set_errno (EOVERFLOW);
return -1; return -1;
} }
struct timespec tsp32[2]; struct timespec tsp32[2], *ptsp32 = NULL;
if (tsp64) if (tsp64)
{ {
tsp32[0] = valid_timespec64_to_timespec (tsp64[0]); tsp32[0] = valid_timespec64_to_timespec (tsp64[0]);
tsp32[1] = valid_timespec64_to_timespec (tsp64[1]); tsp32[1] = valid_timespec64_to_timespec (tsp64[1]);
ptsp32 = tsp32;
} }
ret = INLINE_SYSCALL_CALL (utimensat, fd, file, tsp64 ? &tsp32[0] : NULL, return INLINE_SYSCALL_CALL (utimensat, fd, file, ptsp32, flags);
flags);
#endif #endif
return ret;
} }
libc_hidden_def (__utimensat64_helper) libc_hidden_def (__utimensat64_helper)