[v2,01/14] linux: Simplify clock_getres
Commit Message
With arch-syscall.h it can now assumes the existance of either
__NR_clock_getres or __NR_clock_getres_time64. The 32-bit time_t
support is now only build for !__ASSUME_TIME64_SYSCALLS.
It also uses the time64-support functions to simplify it further.
Checked on x86_64-linux-gnu and i686-linux-gnu (on 5.4 and on 4.15
kernel).
---
sysdeps/unix/sysv/linux/clock_getres.c | 38 ++++++++++----------------
1 file changed, 15 insertions(+), 23 deletions(-)
Comments
On Tue, Sep 8, 2020 at 7:57 AM Adhemerval Zanella via Libc-alpha
<libc-alpha@sourceware.org> wrote:
>
> With arch-syscall.h it can now assumes the existance of either
> __NR_clock_getres or __NR_clock_getres_time64. The 32-bit time_t
> support is now only build for !__ASSUME_TIME64_SYSCALLS.
>
> It also uses the time64-support functions to simplify it further.
>
> Checked on x86_64-linux-gnu and i686-linux-gnu (on 5.4 and on 4.15
> kernel).
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Alistair
> ---
> sysdeps/unix/sysv/linux/clock_getres.c | 38 ++++++++++----------------
> 1 file changed, 15 insertions(+), 23 deletions(-)
>
> diff --git a/sysdeps/unix/sysv/linux/clock_getres.c b/sysdeps/unix/sysv/linux/clock_getres.c
> index 5f6955ab10..6be73c94de 100644
> --- a/sysdeps/unix/sysv/linux/clock_getres.c
> +++ b/sysdeps/unix/sysv/linux/clock_getres.c
> @@ -21,6 +21,7 @@
> #include <time.h>
>
> #include <sysdep-vdso.h>
> +#include <time64-support.h>
> #include <shlib-compat.h>
> #include <kernel-features.h>
>
> @@ -28,36 +29,26 @@
> int
> __clock_getres64 (clockid_t clock_id, struct __timespec64 *res)
> {
> -#ifdef __ASSUME_TIME64_SYSCALLS
> - /* 64 bit ABIs or Newer 32-bit ABIs that only support 64-bit time_t. */
> -# ifndef __NR_clock_getres_time64
> -# define __NR_clock_getres_time64 __NR_clock_getres
> -# endif
> -# ifdef HAVE_CLOCK_GETRES64_VSYSCALL
> - return INLINE_VSYSCALL (clock_getres_time64, 2, clock_id, res);
> -# else
> - return INLINE_SYSCALL_CALL (clock_getres_time64, clock_id, res);
> -# endif
> -#else
> int r;
> - /* Old 32-bit ABI with possible 64-bit time_t support. */
> -# ifdef __NR_clock_getres_time64
> - /* Avoid issue a __NR_clock_getres_time64 syscall on kernels that do not
> - support 64-bit time_t. */
> - static int time64_support = 1;
> - if (atomic_load_relaxed (&time64_support) != 0)
> +
> +#ifndef __NR_clock_getres_time64
> +# define __NR_clock_getres_time64 __NR_clock_getres
> +#endif
> + if (supports_time64 ())
> {
> -# ifdef HAVE_CLOCK_GETRES64_VSYSCALL
> +#ifdef HAVE_CLOCK_GETRES64_VSYSCALL
> r = INLINE_VSYSCALL (clock_getres_time64, 2, clock_id, res);
> -# else
> +#else
> r = INLINE_SYSCALL_CALL (clock_getres_time64, clock_id, res);
> -# endif
> +#endif
> +
> if (r == 0 || errno != ENOSYS)
> return r;
>
> - atomic_store_relaxed (&time64_support, 0);
> + mark_time64_unsupported ();
> }
> -# endif
> +
> +#ifndef __ASSUME_TIME64_SYSCALLS
> /* Fallback code that uses 32-bit support. */
> struct timespec ts32;
> # ifdef HAVE_CLOCK_GETRES_VSYSCALL
> @@ -67,8 +58,9 @@ __clock_getres64 (clockid_t clock_id, struct __timespec64 *res)
> # endif
> if (r == 0)
> *res = valid_timespec_to_timespec64 (ts32);
> - return r;
> #endif
> +
> + return r;
> }
>
> #if __TIMESIZE != 64
> --
> 2.25.1
>
@@ -21,6 +21,7 @@
#include <time.h>
#include <sysdep-vdso.h>
+#include <time64-support.h>
#include <shlib-compat.h>
#include <kernel-features.h>
@@ -28,36 +29,26 @@
int
__clock_getres64 (clockid_t clock_id, struct __timespec64 *res)
{
-#ifdef __ASSUME_TIME64_SYSCALLS
- /* 64 bit ABIs or Newer 32-bit ABIs that only support 64-bit time_t. */
-# ifndef __NR_clock_getres_time64
-# define __NR_clock_getres_time64 __NR_clock_getres
-# endif
-# ifdef HAVE_CLOCK_GETRES64_VSYSCALL
- return INLINE_VSYSCALL (clock_getres_time64, 2, clock_id, res);
-# else
- return INLINE_SYSCALL_CALL (clock_getres_time64, clock_id, res);
-# endif
-#else
int r;
- /* Old 32-bit ABI with possible 64-bit time_t support. */
-# ifdef __NR_clock_getres_time64
- /* Avoid issue a __NR_clock_getres_time64 syscall on kernels that do not
- support 64-bit time_t. */
- static int time64_support = 1;
- if (atomic_load_relaxed (&time64_support) != 0)
+
+#ifndef __NR_clock_getres_time64
+# define __NR_clock_getres_time64 __NR_clock_getres
+#endif
+ if (supports_time64 ())
{
-# ifdef HAVE_CLOCK_GETRES64_VSYSCALL
+#ifdef HAVE_CLOCK_GETRES64_VSYSCALL
r = INLINE_VSYSCALL (clock_getres_time64, 2, clock_id, res);
-# else
+#else
r = INLINE_SYSCALL_CALL (clock_getres_time64, clock_id, res);
-# endif
+#endif
+
if (r == 0 || errno != ENOSYS)
return r;
- atomic_store_relaxed (&time64_support, 0);
+ mark_time64_unsupported ();
}
-# endif
+
+#ifndef __ASSUME_TIME64_SYSCALLS
/* Fallback code that uses 32-bit support. */
struct timespec ts32;
# ifdef HAVE_CLOCK_GETRES_VSYSCALL
@@ -67,8 +58,9 @@ __clock_getres64 (clockid_t clock_id, struct __timespec64 *res)
# endif
if (r == 0)
*res = valid_timespec_to_timespec64 (ts32);
- return r;
#endif
+
+ return r;
}
#if __TIMESIZE != 64