[07/16] linux: Consolidate time implementation
Commit Message
The IFUNC bypass to vDSO is used when USE_IFUNC_TIME is set.
Currently powerpc and x86 defines it. Otherwise the generic
implementation is used, which calls clock_gettime.
Checked on powerpc64le-linux-gnu, powerpc64-linux-gnu,
powerpc-linux-gnu-power4, x86_64-linux-gnu, and i686-linux-gnu.
---
sysdeps/unix/sysv/linux/powerpc/time.c | 32 +---------------
sysdeps/unix/sysv/linux/time.c | 51 ++++++++++++++++++++++++++
sysdeps/unix/sysv/linux/x86/time.c | 27 +-------------
3 files changed, 55 insertions(+), 55 deletions(-)
create mode 100644 sysdeps/unix/sysv/linux/time.c
Comments
On 18/12/19 3:17 am, Adhemerval Zanella wrote:
> The IFUNC bypass to vDSO is used when USE_IFUNC_TIME is set.
> Currently powerpc and x86 defines it. Otherwise the generic
> implementation is used, which calls clock_gettime.
>
> Checked on powerpc64le-linux-gnu, powerpc64-linux-gnu,
> powerpc-linux-gnu-power4, x86_64-linux-gnu, and i686-linux-gnu.
> ---
> sysdeps/unix/sysv/linux/powerpc/time.c | 32 +---------------
> sysdeps/unix/sysv/linux/time.c | 51 ++++++++++++++++++++++++++
> sysdeps/unix/sysv/linux/x86/time.c | 27 +-------------
> 3 files changed, 55 insertions(+), 55 deletions(-)
> create mode 100644 sysdeps/unix/sysv/linux/time.c
>
OK.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
@@ -16,33 +16,5 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
-#include <time.h>
-#include <sysdep.h>
-#include <sysdep-vdso.h>
-
-static time_t
-time_vsyscall (time_t *t)
-{
- return INLINE_VSYSCALL (time, 1, t);
-}
-
-#ifdef SHARED
-# include <dl-vdso.h>
-# include <libc-vdso.h>
-
-# define INIT_ARCH() \
- void *vdso_time = get_vdso_symbol (HAVE_TIME_VSYSCALL);
-
-/* If the vDSO is not available we fall back to the syscall. */
-libc_ifunc (time,
- vdso_time
- ? VDSO_IFUNC_RET (vdso_time)
- : (void *) time_vsyscall);
-
-#else
-time_t
-time (time_t *t)
-{
- return time_vsyscall (t);
-}
-#endif /* !SHARED */
+#define USE_IFUNC_TIME
+#include <sysdeps/unix/sysv/linux/time.c>
new file mode 100644
@@ -0,0 +1,51 @@
+/* time -- Get number of seconds since Epoch. Linux version.
+ Copyright (C) 2019 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+/* Some architecture might optimize the time by setting the plt direct
+ to vDSO symbol by using a IFUNC. */
+#ifdef USE_IFUNC_TIME
+# include <time.h>
+# include <sysdep.h>
+# include <sysdep-vdso.h>
+
+#ifdef SHARED
+# include <dl-vdso.h>
+
+static time_t
+time_syscall (time_t *t)
+{
+ return INLINE_SYSCALL_CALL (time, t);
+}
+
+# undef INIT_ARCH
+# define INIT_ARCH() \
+ void *vdso_time = get_vdso_symbol (HAVE_TIME_VSYSCALL);
+libc_ifunc (time,
+ vdso_time ? VDSO_IFUNC_RET (vdso_time)
+ : (void *) time_syscall);
+
+# else
+time_t
+time (time_t *t)
+{
+ return INLINE_VSYSCALL (time, 1, t);
+}
+# endif /* !SHARED */
+#else /* USE_IFUNC_TIME */
+# include <time/time.c>
+#endif
@@ -16,28 +16,5 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
-#include <time.h>
-#include <sysdep.h>
-#include <sysdep-vdso.h>
-
-static time_t
-time_vsyscall (time_t *t)
-{
- return INLINE_VSYSCALL (time, 1, t);
-}
-
-#ifdef SHARED
-# include <dl-vdso.h>
-# include <libc-vdso.h>
-
-#undef INIT_ARCH
-#define INIT_ARCH()
-/* If the vDSO is not available we fall back on the syscall. */
-libc_ifunc (time, (get_vdso_symbol ("__vdso_time") ?: time_vsyscall))
-#else
-time_t
-time (time_t *t)
-{
- return time_vsyscall (t);
-}
-#endif
+#define USE_IFUNC_TIME
+#include <sysdeps/unix/sysv/linux/time.c>