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Re: PATCH: Add x32 time
On Thu, May 17, 2012 at 5:25 PM, H.J. Lu <hjl.tools@gmail.com> wrote:
> On Thu, May 17, 2012 at 3:06 PM, Roland McGrath <roland@hack.frob.com> wrote:
>> OK, this clinches it for me that we really should be doing this and
>> gettimeofday with syscalls.list enhancements instead.
>>
>>
>
> Those are in C. ?If you compare gettimeofday.c and time.c, excluding
> copyright, there are more codes which are different than common. We
> can define libc_ifunc_vdso in include/libc-symbols.h to cover
>
> # include <dl-vdso.h>
>
> void *time_ifunc (void) __asm__ ("__GI_time");
>
> void *
> time_ifunc (void)
> {
> ?PREPARE_VERSION (linux26, "LINUX_2.6", 61765110);
>
> ?return _dl_vdso_vsym ("__vdso_time", &linux26);
> }
> __asm (".type __GI_time, %gnu_indirect_function");
>
> It should cover most if not all common code.
>
Here is a patch to add libc_ifunc_vdso and libc_ifunc_vdso_hidden.
As it is shown, there is not much in common between
time.c and gettimeofday.c. It will take more much time to
update syscalls.list approach to support this. OK to install?
Thanks,
--
H.J.
---
* include/libc-symbols.h (libc_ifunc_vdso1): New macro.
(libc_ifunc_vdso): Likewise.
(libc_ifunc_vdso_hidden): Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/gettimeofday.c: New file.
* sysdeps/unix/sysv/linux/x86_64/x32/time.c: Likewise.
diff --git a/include/libc-symbols.h b/include/libc-symbols.h
index 12b3639..1d08ab5 100644
--- a/include/libc-symbols.h
+++ b/include/libc-symbols.h
@@ -772,6 +772,23 @@ for linking")
} \
__asm__ (".type " #name ", %gnu_indirect_function");
+#define libc_ifunc_vdso1(name, vdsoname) \
+ extern void *name##_ifunc (void) __asm__ (#name); \
+ void *name##_ifunc (void) \
+ { \
+ PREPARE_VERSION (linux26, "LINUX_2.6", 61765110); \
+ return _dl_vdso_vsym (#vdsoname, &linux26); \
+ } \
+ __asm__ (".type " #name ", %gnu_indirect_function");
+
+/* Macro used for indirection function symbols with vDSO. */
+#define libc_ifunc_vdso(name, vdsoname) \
+ libc_ifunc_vdso1 (name, vdsoname)
+
+/* Macro used for hidden indirection function symbols with vDSO. */
+#define libc_ifunc_vdso_hidden(name, vdsoname) \
+ libc_ifunc_vdso1 (__GI_##name, vdsoname)
+
/* The body of the function is supposed to use __get_cpu_features
which will, if necessary, initialize the data first. */
#define libm_ifunc(name, expr) \
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/gettimeofday.c
b/sysdeps/unix/sysv/linux/x86_64/x32/gettimeofday.c
new file mode 100644
index 0000000..994567f
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/gettimeofday.c
@@ -0,0 +1,35 @@
+/* The gettimeofday system call. Linux/x32 version.
+ Copyright (C) 2012 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
+ <http://www.gnu.org/licenses/>. */
+
+#ifdef SHARED
+# include <dl-vdso.h>
+libc_ifunc_vdso (__gettimeofday, __vdso_gettimeofday)
+#else
+# include <errno.h>
+# include <sysdep.h>
+# include <sys/time.h>
+
+int
+__gettimeofday (struct timeval *tv, struct timezone *tz)
+{
+ return INLINE_SYSCALL (gettimeofday, 2, tv, tz);
+}
+#endif
+
+weak_alias (__gettimeofday, gettimeofday)
+strong_alias (__gettimeofday, __gettimeofday_internal)
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/time.c
b/sysdeps/unix/sysv/linux/x86_64/x32/time.c
new file mode 100644
index 0000000..059cecd
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/time.c
@@ -0,0 +1,61 @@
+/* The time system call. Linux/x32 version.
+ Copyright (C) 2012 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
+ <http://www.gnu.org/licenses/>. */
+
+#include <errno.h>
+#include <sysdep.h>
+#include <time.h>
+
+# undef INLINE_SYSCALL
+# define INLINE_SYSCALL(name, nr, args...) \
+ ({ \
+ unsigned long long int resultvar = INTERNAL_SYSCALL (name, , nr, args); \
+ if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (resultvar, ), 0)) \
+ { \
+ __set_errno (INTERNAL_SYSCALL_ERRNO (resultvar, )); \
+ resultvar = (unsigned long long int) -1LL; \
+ } \
+ (long long int) resultvar; })
+
+# undef INTERNAL_SYSCALL_NCS
+# define INTERNAL_SYSCALL_NCS(name, err, nr, args...) \
+ ({ \
+ unsigned long long int resultvar; \
+ LOAD_ARGS_##nr (args) \
+ LOAD_REGS_##nr \
+ asm volatile ( \
+ "syscall\n\t" \
+ : "=a" (resultvar) \
+ : "0" (name) ASM_ARGS_##nr : "memory", "cc", "r11", "cx"); \
+ (long long int) resultvar; })
+
+# undef INTERNAL_SYSCALL_ERROR_P
+# define INTERNAL_SYSCALL_ERROR_P(val, err) \
+ ((unsigned long long int) (long long int) (val) >= -4095LL)
+
+#ifdef SHARED
+# include <dl-vdso.h>
+libc_ifunc_vdso_hidden (time, __vdso_time)
+#else
+time_t
+time (time_t *t)
+{
+ return INLINE_SYSCALL (time, 1, t);
+}
+#endif
+
+libc_hidden_def (time)