Remove PREPARE_VERSION and PREPARE_VERSION_KNOW

This patch removes the PREPARE_VERSION and PREPARE_VERSION_KNOW macro
and uses a static inline function instead, get_vdso_symbol.  Each
architecture that supports vDSO must define the Linux version and its
hash for symbol resolution (VDSO_NAME and VDSO_HASH macro respectively).

It also organizes the HAVE_*_VSYSCALL for mips, powerpc, and s390 to
define them on a common header.

The idea is to require less code to configure and enable vDSO support
for newer ports.  No semantic changes are expected.

Checked with a build against all affected architectures.

	* sysdeps/unix/make-syscalls.sh: Make vDSO call use get_vdso_symbol.
	* sysdeps/unix/sysv/linux/aarch64/gettimeofday.c (__gettimeofday):
	Use get_vdso_symbol instead of _dl_vdso_vsym.
	* sysdeps/unix/sysv/linux/powerpc/time.c (time): Likewise.
	* sysdeps/unix/sysv/linux/riscv/flush-icache.c
	(__lookup_riscv_flush_icache): Likewise.
	* sysdeps/unix/sysv/linux/x86/gettimeofday.c (__gettimeofday):
	Likewise.
	* sysdeps/unix/sysv/linux/x86/time.c (time): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/gettimeofday.c: Likewise.
	* sysdeps/unix/sysv/linux/aarch64/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/arm/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/i386/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/mips/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/riscv/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/sparc/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/s390/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/aarch64/sysdep.h (VDSO_NAME, VDSO_HASH):
	Define.
	* sysdeps/unix/sysv/linux/arm/sysdep.h (VDSO_NAME, VDSO_HASH):
	Likewise.
	* sysdeps/unix/sysv/linux/i386/sysdep.h (VDSO_NAME, VDSO_HASH):
	Likewise.
	* sysdeps/unix/sysv/linux/riscv/sysdep.h (VDSO_NAME, VDSO_HASH):
	Likewise.
	* sysdeps/unix/sysv/linux/sparc/sysdep.h (VDSO_NAME, VDSO_HASH):
	Likewise.
	* sysdeps/unix/sysv/linux/x86_64/sysdep.h (VDSO_NAME, VDSO_HASH):
	Likewise.
	* sysdeps/unix/sysv/linux/mips/mips32/sysdep.h
	(HAVE_CLOCK_GETTIME_VSYSCALL, HAVE_GETTIMEOFDAY_VSYSCALL): Remove
	definition.
	* sysdeps/unix/sysv/linux/mips/mips64/n32/sysdep.h
	(HAVE_CLOCK_GETTIME_VSYSCALL, HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/mips/mips64/n64/sysdep.h
	(HAVE_CLOCK_GETTIME_VSYSCALL, HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/sysdep.h
	(HAVE_CLOCK_GETTIME_VSYSCALL, HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h
	(HAVE_CLOCK_GETTIME_VSYSCALL, HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-32/sysdep.h
	(HAVE_CLOCK_GETRES_VSYSCALL, HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETTIMEOFDAY_VSYSCALL, HAVE_GETCPU_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-64/sysdep.h
	(HAVE_CLOCK_GETRES_VSYSCALL, HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETTIMEOFDAY_VSYSCALL, HAVE_GETCPU_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/mips/sysdep.h: New file.
	* sysdeps/unix/sysv/linux/powerpc/sysdep.h: Likewise.
	* sysdeps/unix/sysv/linux/s390/sysdep.h: Likewise.
	* sysdeps/unix/sysv/linux/dl-vdso.h (PREPARE_VERSION,
	PREPARE_VERSION_KNOWN, VDSO_NAME_LINUX_2_6, VDSO_HASH_LINUX_2_6,
	VDSO_NAME_LINUX_2_6_15, VDSO_HASH_LINUX_2_6_15,
	VDSO_NAME_LINUX_2_6_29, VDSO_HASH_LINUX_2_6_29,
	VDSO_NAME_LINUX_4_15, VDSO_HASH_LINUX_4_15): Remove defines.
	(get_vdso_symbol): New function.

32 files changed, 161 insertions, 154 deletions

diff --git a/sysdeps/unix/sysv/linux/aarch64/gettimeofday.c b/sysdeps/unix/sysv/linux/aarch64/gettimeofday.c
index ccec52e363..1ec98bf161 100644
--- a/sysdeps/unix/sysv/linux/aarch64/gettimeofday.c
+++ b/sysdeps/unix/sysv/linux/aarch64/gettimeofday.c
@@ -20,12 +20,10 @@
    putting it into *tv and *tz.  If tz is null, *tz is not filled.
    Returns 0 on success, -1 on errors.  */
 
+#include <sys/time.h>
+
 #ifdef SHARED
 
-# define __gettimeofday __redirect___gettimeofday
-# include <sys/time.h>
-# undef __gettimeofday
-# define HAVE_VSYSCALL
 # include <dl-vdso.h>
 # include <sysdep-vdso.h>
 
@@ -38,25 +36,14 @@ __gettimeofday_vsyscall (struct timeval *tv, struct timezone *tz)
   return INLINE_VSYSCALL (gettimeofday, 2, tv, tz);
 }
 
-/* PREPARE_VERSION_KNOWN will need an __LP64__ ifdef when ILP32 support
-   goes in.  See _libc_vdso_platform_setup in
-   sysdeps/unix/sysv/linux/aarch64/init-first.c.  */
-
-# undef INIT_ARCH
-# define INIT_ARCH() \
-	   PREPARE_VERSION_KNOWN (linux_version, LINUX_2_6_39); \
-	   void *vdso_gettimeofday = \
-	     _dl_vdso_vsym ("__kernel_gettimeofday", &linux_version);
-
-libc_ifunc_hidden (__redirect___gettimeofday, __gettimeofday,
-		   vdso_gettimeofday ?: (void *) __gettimeofday_vsyscall)
-
-__hidden_ver1 (__gettimeofday_vsyscall, __GI___gettimeofday,
-	       __gettimeofday_vsyscall);
+# define INIT_ARCH()
+libc_ifunc_hidden (__gettimeofday, __gettimeofday,
+		   (get_vdso_symbol ("__kernel_gettimeofday")
+		    ?: __gettimeofday_vsyscall))
+libc_hidden_def (__gettimeofday)
 
 #else
 
-# include <sys/time.h>
 # include <sysdep.h>
 int
 __gettimeofday (struct timeval *tv, struct timezone *tz)
diff --git a/sysdeps/unix/sysv/linux/aarch64/init-first.c b/sysdeps/unix/sysv/linux/aarch64/init-first.c
index 6ae2be38c5..16b28be835 100644
--- a/sysdeps/unix/sysv/linux/aarch64/init-first.c
+++ b/sysdeps/unix/sysv/linux/aarch64/init-first.c
@@ -26,21 +26,15 @@ int (*VDSO_SYMBOL(clock_getres)) (clockid_t, struct timespec *);
 static inline void
 _libc_vdso_platform_setup (void)
 {
-#ifdef __LP64__
-  PREPARE_VERSION_KNOWN (linux_version, LINUX_2_6_39);
-#else
-  PREPARE_VERSION_KNOWN (linux_version, LINUX_4_9);
-#endif
-
-  void *p = _dl_vdso_vsym ("__kernel_gettimeofday", &linux_version);
+  void *p = get_vdso_symbol ("__kernel_gettimeofday");
   PTR_MANGLE (p);
   VDSO_SYMBOL(gettimeofday) = p;
 
-  p = _dl_vdso_vsym ("__kernel_clock_gettime", &linux_version);
+  p = get_vdso_symbol ("__kernel_clock_gettime");
   PTR_MANGLE (p);
   VDSO_SYMBOL(clock_gettime) = p;
 
-  p = _dl_vdso_vsym ("__kernel_clock_getres", &linux_version);
+  p = get_vdso_symbol ("__kernel_clock_getres");
   PTR_MANGLE (p);
   VDSO_SYMBOL(clock_getres) = p;
 }
diff --git a/sysdeps/unix/sysv/linux/aarch64/sysdep.h b/sysdeps/unix/sysv/linux/aarch64/sysdep.h
index 95cb7eb4ab..37d70ca4af 100644
--- a/sysdeps/unix/sysv/linux/aarch64/sysdep.h
+++ b/sysdeps/unix/sysv/linux/aarch64/sysdep.h
@@ -151,6 +151,13 @@
 
 #else /* not __ASSEMBLER__ */
 
+# ifdef __LP64__
+#  define VDSO_NAME  "LINUX_2.6.39"
+#  define VDSO_HASH  123718537
+# else
+#  define VDSO_NAME  "LINUX_4.9"
+#  define VDSO_HASH  61765625
+# endif
 
 /* List of system calls which are supported as vsyscalls.  */
 # define HAVE_CLOCK_GETRES_VSYSCALL	1
diff --git a/sysdeps/unix/sysv/linux/arm/init-first.c b/sysdeps/unix/sysv/linux/arm/init-first.c
index d2453dde7a..56ae7393c4 100644
--- a/sysdeps/unix/sysv/linux/arm/init-first.c
+++ b/sysdeps/unix/sysv/linux/arm/init-first.c
@@ -27,13 +27,11 @@ int (*VDSO_SYMBOL(clock_gettime)) (clockid_t, struct timespec *);
 static inline void
 _libc_vdso_platform_setup (void)
 {
-  PREPARE_VERSION_KNOWN (linux26, LINUX_2_6);
-
-  void *p = _dl_vdso_vsym ("__vdso_gettimeofday", &linux26);
+  void *p = get_vdso_symbol ("__vdso_gettimeofday");
   PTR_MANGLE (p);
   VDSO_SYMBOL (gettimeofday) = p;
 
-  p = _dl_vdso_vsym ("__vdso_clock_gettime", &linux26);
+  p = get_vdso_symbol ("__vdso_clock_gettime");
   PTR_MANGLE (p);
   VDSO_SYMBOL (clock_gettime) = p;
 }
diff --git a/sysdeps/unix/sysv/linux/arm/sysdep.h b/sysdeps/unix/sysv/linux/arm/sysdep.h
index ce42f352fa..9eea48de14 100644
--- a/sysdeps/unix/sysv/linux/arm/sysdep.h
+++ b/sysdeps/unix/sysv/linux/arm/sysdep.h
@@ -388,6 +388,9 @@ __local_syscall_error:						\
 #undef INTERNAL_SYSCALL_ERRNO
 #define INTERNAL_SYSCALL_ERRNO(val, err)	(-(val))
 
+#define VDSO_NAME  "LINUX_2.6"
+#define VDSO_HASH  61765110
+
 /* List of system calls which are supported as vsyscalls.  */
 #define HAVE_CLOCK_GETTIME_VSYSCALL	1
 #define HAVE_GETTIMEOFDAY_VSYSCALL	1
diff --git a/sysdeps/unix/sysv/linux/dl-vdso.h b/sysdeps/unix/sysv/linux/dl-vdso.h
index c37c83d71f..5e40eac3ee 100644
--- a/sysdeps/unix/sysv/linux/dl-vdso.h
+++ b/sysdeps/unix/sysv/linux/dl-vdso.h
@@ -22,40 +22,18 @@
 #include <assert.h>
 #include <ldsodefs.h>
 #include <dl-hash.h>
-
-/* Create version number record for lookup.  */
-static inline struct r_found_version
-prepare_version_base (const char *name, ElfW(Word) hash)
-{
-  assert (hash == _dl_elf_hash (name));
-  return (struct r_found_version) { name, hash, 1, NULL };
-}
-#define prepare_version(vname) \
-  prepare_version_base (VDSO_NAME_##vname, VDSO_HASH_##vname)
-
-/* Use this for the known version sets defined below, where we
-   record their precomputed hash values only once, in this file.  */
-#define PREPARE_VERSION_KNOWN(var, vname) \
-  struct r_found_version var = prepare_version (vname);
-
-#define VDSO_NAME_LINUX_2_6	"LINUX_2.6"
-#define VDSO_HASH_LINUX_2_6	61765110
-#define VDSO_NAME_LINUX_2_6_15	"LINUX_2.6.15"
-#define VDSO_HASH_LINUX_2_6_15	123718565
-#define VDSO_NAME_LINUX_2_6_29	"LINUX_2.6.29"
-#define VDSO_HASH_LINUX_2_6_29	123718585
-#define VDSO_NAME_LINUX_2_6_39	"LINUX_2.6.39"
-#define VDSO_HASH_LINUX_2_6_39	123718537
-#define VDSO_NAME_LINUX_4	"LINUX_4"
-#define VDSO_HASH_LINUX_4	14921332
-#define VDSO_NAME_LINUX_4_9	"LINUX_4.9"
-#define VDSO_HASH_LINUX_4_9	61765625
-#define VDSO_NAME_LINUX_4_15	"LINUX_4.15"
-#define VDSO_HASH_LINUX_4_15	182943605
+#include <libc-vdso.h>
 
 /* Functions for resolving symbols in the VDSO link map.  */
 extern void *_dl_vdso_vsym (const char *name,
 			    const struct r_found_version *version)
       attribute_hidden;
 
+static inline void *
+get_vdso_symbol (const char *symbol)
+{
+  struct r_found_version rfv = { VDSO_NAME, VDSO_HASH, 1, NULL };
+  return _dl_vdso_vsym (symbol, &rfv);
+}
+
 #endif /* dl-vdso.h */
diff --git a/sysdeps/unix/sysv/linux/i386/init-first.c b/sysdeps/unix/sysv/linux/i386/init-first.c
index 3453738530..e785664637 100644
--- a/sysdeps/unix/sysv/linux/i386/init-first.c
+++ b/sysdeps/unix/sysv/linux/i386/init-first.c
@@ -34,9 +34,7 @@ clock_gettime_syscall (clockid_t id, struct timespec *tp)
 static inline void
 __vdso_platform_setup (void)
 {
-  PREPARE_VERSION_KNOWN (linux26, LINUX_2_6);
-
-  void *p = _dl_vdso_vsym ("__vdso_clock_gettime", &linux26);
+  void *p = get_vdso_symbol ("__vdso_clock_gettime");
   if (p == NULL)
     p = clock_gettime_syscall;
   PTR_MANGLE (p);
diff --git a/sysdeps/unix/sysv/linux/i386/sysdep.h b/sysdeps/unix/sysv/linux/i386/sysdep.h
index 0e76b6b111..cdba552af7 100644
--- a/sysdeps/unix/sysv/linux/i386/sysdep.h
+++ b/sysdeps/unix/sysv/linux/i386/sysdep.h
@@ -309,6 +309,9 @@ struct libc_do_syscall_args
 #define INLINE_SYSCALL_ERROR_RETURN_VALUE(resultvar) \
   __syscall_error (-(resultvar))
 
+# define VDSO_NAME  "LINUX_2.6"
+# define VDSO_HASH  61765110
+
 /* List of system calls which are supported as vsyscalls.  */
 # define HAVE_CLOCK_GETTIME_VSYSCALL    1
 # define HAVE_GETTIMEOFDAY_VSYSCALL     1
diff --git a/sysdeps/unix/sysv/linux/mips/init-first.c b/sysdeps/unix/sysv/linux/mips/init-first.c
index ea5433a9e4..05cf438eb1 100644
--- a/sysdeps/unix/sysv/linux/mips/init-first.c
+++ b/sysdeps/unix/sysv/linux/mips/init-first.c
@@ -26,13 +26,11 @@ int (*VDSO_SYMBOL(clock_gettime)) (clockid_t, struct timespec *);
 static inline void
 _libc_vdso_platform_setup (void)
 {
-  PREPARE_VERSION_KNOWN (linux26, LINUX_2_6);
-
-  void *p = _dl_vdso_vsym ("__vdso_gettimeofday", &linux26);
+  void *p = get_vdso_symbol ("__vdso_gettimeofday");
   PTR_MANGLE (p);
   VDSO_SYMBOL (gettimeofday) = p;
 
-  p = _dl_vdso_vsym ("__vdso_clock_gettime", &linux26);
+  p = get_vdso_symbol ("__vdso_clock_gettime");
   PTR_MANGLE (p);
   VDSO_SYMBOL (clock_gettime) = p;
 }
diff --git a/sysdeps/unix/sysv/linux/mips/mips32/sysdep.h b/sysdeps/unix/sysv/linux/mips/mips32/sysdep.h
index f5312e8e2a..09d9040efd 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/sysdep.h
+++ b/sysdeps/unix/sysv/linux/mips/mips32/sysdep.h
@@ -19,6 +19,7 @@
 #define _LINUX_MIPS_MIPS32_SYSDEP_H 1
 
 /* There is some commonality.  */
+#include <sysdeps/unix/sysv/linux/mips/sysdep.h>
 #include <sysdeps/unix/sysv/linux/sysdep.h>
 #include <sysdeps/unix/mips/mips32/sysdep.h>
 
@@ -360,10 +361,6 @@ libc_hidden_proto (__mips_syscall7, nomips16)
     _ret;								\
   })
 
-/* List of system calls which are supported as vsyscalls.  */
-#define HAVE_CLOCK_GETTIME_VSYSCALL	1
-#define HAVE_GETTIMEOFDAY_VSYSCALL	1
-
 #endif /* __ASSEMBLER__ */
 
 /* Pointer mangling is not yet supported for MIPS.  */
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/sysdep.h b/sysdeps/unix/sysv/linux/mips/mips64/n32/sysdep.h
index 0c32cc3851..c276b0086a 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n32/sysdep.h
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/sysdep.h
@@ -19,6 +19,7 @@
 #define _LINUX_MIPS_SYSDEP_H 1
 
 /* There is some commonality.  */
+#include <sysdeps/unix/sysv/linux/mips/sysdep.h>
 #include <sysdeps/unix/sysv/linux/sysdep.h>
 #include <sysdeps/unix/mips/mips64/n32/sysdep.h>
 
@@ -308,10 +309,6 @@
     _ret;								\
   })
 
-/* List of system calls which are supported as vsyscalls.  */
-#define HAVE_CLOCK_GETTIME_VSYSCALL	1
-#define HAVE_GETTIMEOFDAY_VSYSCALL	1
-
 #endif /* __ASSEMBLER__ */
 
 /* Pointer mangling is not yet supported for MIPS.  */
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/sysdep.h b/sysdeps/unix/sysv/linux/mips/mips64/n64/sysdep.h
index c2fe86d1cd..9d574c720a 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n64/sysdep.h
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/sysdep.h
@@ -19,6 +19,7 @@
 #define _LINUX_MIPS_SYSDEP_H 1
 
 /* There is some commonality.  */
+#include <sysdeps/unix/sysv/linux/mips/sysdep.h>
 #include <sysdeps/unix/sysv/linux/sysdep.h>
 #include <sysdeps/unix/mips/mips64/n64/sysdep.h>
 
@@ -304,10 +305,6 @@
     _ret;								\
   })
 
-/* List of system calls which are supported as vsyscalls.  */
-#define HAVE_CLOCK_GETTIME_VSYSCALL	1
-#define HAVE_GETTIMEOFDAY_VSYSCALL	1
-
 #endif /* __ASSEMBLER__ */
 
 /* Pointer mangling is not yet supported for MIPS.  */
diff --git a/sysdeps/unix/sysv/linux/mips/sysdep.h b/sysdeps/unix/sysv/linux/mips/sysdep.h
new file mode 100644
index 0000000000..0f3399f82d
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/mips/sysdep.h
@@ -0,0 +1,24 @@
+/* Syscall definitions, Linux MIPS generic 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
+   <http://www.gnu.org/licenses/>.  */
+
+#define VDSO_NAME  "LINUX_2.6"
+#define VDSO_HASH  61765110
+
+/* List of system calls which are supported as vsyscalls.  */
+#define HAVE_CLOCK_GETTIME_VSYSCALL     1
+#define HAVE_GETTIMEOFDAY_VSYSCALL      1
diff --git a/sysdeps/unix/sysv/linux/powerpc/gettimeofday.c b/sysdeps/unix/sysv/linux/powerpc/gettimeofday.c
index 7605357307..40549fe6dd 100644
--- a/sysdeps/unix/sysv/linux/powerpc/gettimeofday.c
+++ b/sysdeps/unix/sysv/linux/powerpc/gettimeofday.c
@@ -57,9 +57,8 @@ __gettimeofday_syscall (struct timeval *tv, struct timezone *tz)
   return INLINE_SYSCALL (gettimeofday, 2, tv, tz);
 }
 
-# define INIT_ARCH()						\
-  PREPARE_VERSION_KNOWN (linux2615, LINUX_2_6_15);		\
-  void *vdso_gettimeofday = _dl_vdso_vsym ("__kernel_gettimeofday", &linux2615);
+# define INIT_ARCH() \
+  void *vdso_gettimeofday = get_vdso_symbol ("__kernel_gettimeofday")
 
 /* If the vDSO is not available we fall back syscall.  */
 libc_ifunc_hidden (__redirect___gettimeofday, __gettimeofday,
diff --git a/sysdeps/unix/sysv/linux/powerpc/init-first.c b/sysdeps/unix/sysv/linux/powerpc/init-first.c
index 4b285fb842..b1618ed0b1 100644
--- a/sysdeps/unix/sysv/linux/powerpc/init-first.c
+++ b/sysdeps/unix/sysv/linux/powerpc/init-first.c
@@ -37,29 +37,27 @@ void *VDSO_SYMBOL(sigtramp_rt32);
 static inline void
 _libc_vdso_platform_setup (void)
 {
-  PREPARE_VERSION_KNOWN (linux2615, LINUX_2_6_15);
-
-  void *p = _dl_vdso_vsym ("__kernel_gettimeofday", &linux2615);
+  void *p = get_vdso_symbol ("__kernel_gettimeofday");
   PTR_MANGLE (p);
   VDSO_SYMBOL (gettimeofday) = p;
 
-  p = _dl_vdso_vsym ("__kernel_clock_gettime", &linux2615);
+  p = get_vdso_symbol ("__kernel_clock_gettime");
   PTR_MANGLE (p);
   VDSO_SYMBOL (clock_gettime) = p;
 
-  p = _dl_vdso_vsym ("__kernel_clock_getres", &linux2615);
+  p = get_vdso_symbol ("__kernel_clock_getres");
   PTR_MANGLE (p);
   VDSO_SYMBOL (clock_getres) = p;
 
-  p = _dl_vdso_vsym ("__kernel_get_tbfreq", &linux2615);
+  p = get_vdso_symbol ("__kernel_get_tbfreq");
   PTR_MANGLE (p);
   VDSO_SYMBOL (get_tbfreq) = p;
 
-  p = _dl_vdso_vsym ("__kernel_getcpu", &linux2615);
+  p = get_vdso_symbol ("__kernel_getcpu");
   PTR_MANGLE (p);
   VDSO_SYMBOL (getcpu) = p;
 
-  p = _dl_vdso_vsym ("__kernel_time", &linux2615);
+  p = get_vdso_symbol ("__kernel_time");
   PTR_MANGLE (p);
   VDSO_SYMBOL (time) = p;
 
@@ -69,12 +67,10 @@ _libc_vdso_platform_setup (void)
      There is no need to pointer mangle these symbol because they will
      used only for pointer comparison.  */
 #if defined(__PPC64__) || defined(__powerpc64__)
-  VDSO_SYMBOL(sigtramp_rt64) = _dl_vdso_vsym ("__kernel_sigtramp_rt64",
-					      &linux2615);
+  VDSO_SYMBOL(sigtramp_rt64) =  get_vdso_symbol ("__kernel_sigtramp_rt64");
 #else
-  VDSO_SYMBOL(sigtramp32) = _dl_vdso_vsym ("__kernel_sigtramp32", &linux2615);
-  VDSO_SYMBOL(sigtramp_rt32) = _dl_vdso_vsym ("__kernel_sigtramp_rt32",
-					      &linux2615);
+  VDSO_SYMBOL(sigtramp32) = get_vdso_symbol ("__kernel_sigtramp32");
+  VDSO_SYMBOL(sigtramp_rt32) = get_vdso_symbol ("__kernel_sigtramp_rt32");
 #endif
 }
 
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/sysdep.h b/sysdeps/unix/sysv/linux/powerpc/powerpc32/sysdep.h
index 75d5831018..1cbf1596d5 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/sysdep.h
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/sysdep.h
@@ -18,6 +18,7 @@
 #ifndef _LINUX_POWERPC_SYSDEP_H
 #define _LINUX_POWERPC_SYSDEP_H 1
 
+#include <sysdeps/unix/sysv/linux/powerpc/sysdep.h>
 #include <sysdeps/unix/sysv/linux/sysdep.h>
 #include <sysdeps/unix/powerpc/sysdep.h>
 #include <tls.h>
@@ -144,12 +145,6 @@
     sc_ret;								      \
   })
 
-/* List of system calls which are supported as vsyscalls.  */
-# define HAVE_CLOCK_GETRES_VSYSCALL	1
-# define HAVE_CLOCK_GETTIME_VSYSCALL	1
-# define HAVE_GETCPU_VSYSCALL		1
-
-
 # define LOADARGS_0(name, dummy)					      \
 	r0 = name
 # define LOADARGS_1(name, __arg1) \
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h b/sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h
index e662cca4fe..fac7a9ac2e 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h
@@ -20,6 +20,7 @@
 #ifndef _LINUX_POWERPC_SYSDEP_H
 #define _LINUX_POWERPC_SYSDEP_H 1
 
+#include <sysdeps/unix/sysv/linux/powerpc/sysdep.h>
 #include <sysdeps/unix/sysv/linux/sysdep.h>
 #include <sysdeps/unix/powerpc/sysdep.h>
 #include <tls.h>
@@ -60,11 +61,6 @@
     sc_ret;								      \
   })
 
-/* List of system calls which are supported as vsyscalls.  */
-#define HAVE_CLOCK_GETRES_VSYSCALL	1
-#define HAVE_CLOCK_GETTIME_VSYSCALL	1
-#define HAVE_GETCPU_VSYSCALL		1
-
 /* Define a macro which expands inline into the wrapper code for a system
    call. This use is for internal calls that do not need to handle errors
    normally. It will never touch errno. This returns just what the kernel
diff --git a/sysdeps/unix/sysv/linux/powerpc/sysdep.h b/sysdeps/unix/sysv/linux/powerpc/sysdep.h
new file mode 100644
index 0000000000..c72c93dfa0
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/powerpc/sysdep.h
@@ -0,0 +1,25 @@
+/* Syscall definitions, Linux PowerPC generic 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
+   <http://www.gnu.org/licenses/>.  */
+
+#define VDSO_NAME  "LINUX_2.6.15"
+#define VDSO_HASH  123718565
+
+/* List of system calls which are supported as vsyscalls.  */
+#define HAVE_CLOCK_GETRES_VSYSCALL	1
+#define HAVE_CLOCK_GETTIME_VSYSCALL	1
+#define HAVE_GETCPU_VSYSCALL		1
diff --git a/sysdeps/unix/sysv/linux/powerpc/time.c b/sysdeps/unix/sysv/linux/powerpc/time.c
index 41092b3b98..2a0b776927 100644
--- a/sysdeps/unix/sysv/linux/powerpc/time.c
+++ b/sysdeps/unix/sysv/linux/powerpc/time.c
@@ -66,9 +66,8 @@ time_syscall (time_t *t)
   return result;
 }
 
-# define INIT_ARCH()						\
-  PREPARE_VERSION_KNOWN (linux2615, LINUX_2_6_15);		\
-  void *vdso_time = _dl_vdso_vsym ("__kernel_time", &linux2615);
+# define INIT_ARCH() \
+  void *vdso_time = get_vdso_symbol ("__kernel_time");
 
 /* If the vDSO is not available we fall back to the syscall.  */
 libc_ifunc_hidden (__redirect_time, time,
diff --git a/sysdeps/unix/sysv/linux/riscv/flush-icache.c b/sysdeps/unix/sysv/linux/riscv/flush-icache.c
index 4f05542996..c5bd60d9c2 100644
--- a/sysdeps/unix/sysv/linux/riscv/flush-icache.c
+++ b/sysdeps/unix/sysv/linux/riscv/flush-icache.c
@@ -38,9 +38,7 @@ __riscv_flush_icache_syscall (void *start, void *end, unsigned long int flags)
 static func_type
 __lookup_riscv_flush_icache (void)
 {
-  PREPARE_VERSION_KNOWN (linux_version, LINUX_4_15);
-
-  func_type func = _dl_vdso_vsym ("__vdso_flush_icache", &linux_version);
+  func_type func = get_vdso_symbol ("__vdso_flush_icache");
 
   /* If there is no vDSO entry then call the system call directly.  All Linux
      versions provide the vDSO entry, but QEMU's user-mode emulation doesn't
diff --git a/sysdeps/unix/sysv/linux/riscv/init-first.c b/sysdeps/unix/sysv/linux/riscv/init-first.c
index b8198102df..19812c5720 100644
--- a/sysdeps/unix/sysv/linux/riscv/init-first.c
+++ b/sysdeps/unix/sysv/linux/riscv/init-first.c
@@ -32,21 +32,19 @@ long int (*VDSO_SYMBOL (clock_getres)) (clockid_t, struct timespec *)
 static inline void
 _libc_vdso_platform_setup (void)
 {
-  PREPARE_VERSION_KNOWN (linux_version, LINUX_4_15);
-
-  void *p = _dl_vdso_vsym ("__vdso_getcpu", &linux_version);
+  void *p = get_vdso_symbol ("__vdso_getcpu");
   PTR_MANGLE (p);
   VDSO_SYMBOL (getcpu) = p;
 
-  p = _dl_vdso_vsym ("__vdso_gettimeofday", &linux_version);
+  p = get_vdso_symbol ("__vdso_gettimeofday");
   PTR_MANGLE (p);
   VDSO_SYMBOL (gettimeofday) = p;
 
-  p = _dl_vdso_vsym ("__vdso_clock_gettime", &linux_version);
+  p = get_vdso_symbol ("__vdso_clock_gettime");
   PTR_MANGLE (p);
   VDSO_SYMBOL (clock_gettime) = p;
 
-  p = _dl_vdso_vsym ("__vdso_clock_getres", &linux_version);
+  p = get_vdso_symbol ("__vdso_clock_getres");
   PTR_MANGLE (p);
   VDSO_SYMBOL (clock_getres) = p;
 }
diff --git a/sysdeps/unix/sysv/linux/riscv/sysdep.h b/sysdeps/unix/sysv/linux/riscv/sysdep.h
index e0f2248f95..b12dd18a8d 100644
--- a/sysdeps/unix/sysv/linux/riscv/sysdep.h
+++ b/sysdeps/unix/sysv/linux/riscv/sysdep.h
@@ -121,6 +121,9 @@
 
 #ifndef __ASSEMBLER__
 
+# define VDSO_NAME  "LINUX_4.15"
+# define VDSO_HASH  182943605
+
 /* List of system calls which are supported as vsyscalls.  */
 # define HAVE_CLOCK_GETRES_VSYSCALL	1
 # define HAVE_CLOCK_GETTIME_VSYSCALL	1
diff --git a/sysdeps/unix/sysv/linux/s390/init-first.c b/sysdeps/unix/sysv/linux/s390/init-first.c
index f3ff19bdfa..ac4c536114 100644
--- a/sysdeps/unix/sysv/linux/s390/init-first.c
+++ b/sysdeps/unix/sysv/linux/s390/init-first.c
@@ -34,21 +34,19 @@ long int (*VDSO_SYMBOL(getcpu)) (unsigned *, unsigned *, void *)
 static inline void
 _libc_vdso_platform_setup (void)
 {
-  PREPARE_VERSION_KNOWN (linux2629, LINUX_2_6_29);
-
-  void *p = _dl_vdso_vsym ("__kernel_gettimeofday", &linux2629);
+  void *p = get_vdso_symbol ("__kernel_gettimeofday");
   PTR_MANGLE (p);
   VDSO_SYMBOL (gettimeofday) = p;
 
-  p = _dl_vdso_vsym ("__kernel_clock_gettime", &linux2629);
+  p = get_vdso_symbol ("__kernel_clock_gettime");
   PTR_MANGLE (p);
   VDSO_SYMBOL (clock_gettime) = p;
 
-  p = _dl_vdso_vsym ("__kernel_clock_getres", &linux2629);
+  p = get_vdso_symbol ("__kernel_clock_getres");
   PTR_MANGLE (p);
   VDSO_SYMBOL (clock_getres) = p;
 
-  p = _dl_vdso_vsym ("__kernel_getcpu", &linux2629);
+  p = get_vdso_symbol ("__kernel_getcpu");
   PTR_MANGLE (p);
   VDSO_SYMBOL (getcpu) = p;
 }
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/sysdep.h b/sysdeps/unix/sysv/linux/s390/s390-32/sysdep.h
index 1b39ab1e25..bdede296a5 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-32/sysdep.h
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/sysdep.h
@@ -21,6 +21,7 @@
 
 #include <sysdeps/s390/s390-32/sysdep.h>
 #include <sysdeps/unix/sysdep.h>
+#include <sysdeps/unix/sysv/linux/s390/sysdep.h>
 #include <sysdeps/unix/sysv/linux/sysdep.h>
 #include <dl-sysdep.h>	/* For RTLD_PRIVATE_ERRNO.  */
 #include <tls.h>
@@ -271,12 +272,6 @@
 #define ASMFMT_5 , "0" (gpr2), "d" (gpr3), "d" (gpr4), "d" (gpr5), "d" (gpr6)
 #define ASMFMT_6 , "0" (gpr2), "d" (gpr3), "d" (gpr4), "d" (gpr5), "d" (gpr6), "d" (gpr7)
 
-/* List of system calls which are supported as vsyscalls.  */
-#define HAVE_CLOCK_GETRES_VSYSCALL	1
-#define HAVE_CLOCK_GETTIME_VSYSCALL	1
-#define HAVE_GETTIMEOFDAY_VSYSCALL	1
-#define HAVE_GETCPU_VSYSCALL		1
-
 /* Pointer mangling support.  */
 #if IS_IN (rtld)
 /* We cannot use the thread descriptor because in ld.so we use setjmp
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/sysdep.h b/sysdeps/unix/sysv/linux/s390/s390-64/sysdep.h
index a0102ac0f8..5c6b818517 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/sysdep.h
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/sysdep.h
@@ -22,6 +22,7 @@
 
 #include <sysdeps/s390/s390-64/sysdep.h>
 #include <sysdeps/unix/sysdep.h>
+#include <sysdeps/unix/sysv/linux/s390/sysdep.h>
 #include <sysdeps/unix/sysv/linux/sysdep.h>
 #include <dl-sysdep.h>	/* For RTLD_PRIVATE_ERRNO.  */
 #include <tls.h>
@@ -277,12 +278,6 @@
 #define ASMFMT_5 , "0" (gpr2), "d" (gpr3), "d" (gpr4), "d" (gpr5), "d" (gpr6)
 #define ASMFMT_6 , "0" (gpr2), "d" (gpr3), "d" (gpr4), "d" (gpr5), "d" (gpr6), "d" (gpr7)
 
-/* List of system calls which are supported as vsyscalls.  */
-#define HAVE_CLOCK_GETRES_VSYSCALL	1
-#define HAVE_CLOCK_GETTIME_VSYSCALL	1
-#define HAVE_GETTIMEOFDAY_VSYSCALL	1
-#define HAVE_GETCPU_VSYSCALL		1
-
 #define SINGLE_THREAD_BY_GLOBAL		1
 
 /* Pointer mangling support.  */
diff --git a/sysdeps/unix/sysv/linux/s390/sysdep.h b/sysdeps/unix/sysv/linux/s390/sysdep.h
new file mode 100644
index 0000000000..3dfb359e9d
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/s390/sysdep.h
@@ -0,0 +1,26 @@
+/* Syscall definitions, Linux s390 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
+   <http://www.gnu.org/licenses/>.  */
+
+#define VDSO_NAME  "LINUX_2.6.29"
+#define VDSO_HASH  123718585
+
+/* List of system calls which are supported as vsyscalls.  */
+#define HAVE_CLOCK_GETRES_VSYSCALL	1
+#define HAVE_CLOCK_GETTIME_VSYSCALL	1
+#define HAVE_GETTIMEOFDAY_VSYSCALL	1
+#define HAVE_GETCPU_VSYSCALL		1
diff --git a/sysdeps/unix/sysv/linux/sparc/init-first.c b/sysdeps/unix/sysv/linux/sparc/init-first.c
index 2f5c70ad4d..ef5bfb7b79 100644
--- a/sysdeps/unix/sysv/linux/sparc/init-first.c
+++ b/sysdeps/unix/sysv/linux/sparc/init-first.c
@@ -28,13 +28,11 @@ long int (*VDSO_SYMBOL (clock_gettime)) (clockid_t, struct timespec *)
 static inline void
 _libc_vdso_platform_setup (void)
 {
-  PREPARE_VERSION_KNOWN (linux_version, LINUX_2_6);
-
-  void *p = _dl_vdso_vsym ("__vdso_gettimeofday", &linux_version);
+  void *p = get_vdso_symbol ("__vdso_gettimeofday");
   PTR_MANGLE (p);
   VDSO_SYMBOL (gettimeofday) = p;
 
-  p = _dl_vdso_vsym ("__vdso_clock_gettime", &linux_version);
+  p = get_vdso_symbol ("__vdso_clock_gettime");
   PTR_MANGLE (p);
   VDSO_SYMBOL (clock_gettime) = p;
 }
diff --git a/sysdeps/unix/sysv/linux/sparc/sysdep.h b/sysdeps/unix/sysv/linux/sparc/sysdep.h
index 470644c6c3..5115711b2c 100644
--- a/sysdeps/unix/sysv/linux/sparc/sysdep.h
+++ b/sysdeps/unix/sysv/linux/sparc/sysdep.h
@@ -41,6 +41,9 @@
     _ret;								\
   })
 
+# define VDSO_NAME  "LINUX_2.6"
+# define VDSO_HASH  61765110
+
 /* List of system calls which are supported as vsyscalls.  */
 # define HAVE_CLOCK_GETTIME_VSYSCALL	1
 # define HAVE_GETTIMEOFDAY_VSYSCALL	1
diff --git a/sysdeps/unix/sysv/linux/x86/gettimeofday.c b/sysdeps/unix/sysv/linux/x86/gettimeofday.c
index bd858b6cf5..2d9248ee26 100644
--- a/sysdeps/unix/sysv/linux/x86/gettimeofday.c
+++ b/sysdeps/unix/sysv/linux/x86/gettimeofday.c
@@ -22,6 +22,8 @@
 
 # include <dl-vdso.h>
 # include <errno.h>
+# include <sysdep-vdso.h>
+# include <sysdep-vdso.h>
 
 static int
 __gettimeofday_syscall (struct timeval *tv, struct timezone *tz)
@@ -36,12 +38,11 @@ __gettimeofday_syscall (struct timeval *tv, struct timezone *tz)
 #  define __gettimeofday_type __gettimeofday
 # endif
 
-# undef INIT_ARCH
-# define INIT_ARCH() PREPARE_VERSION_KNOWN (linux26, LINUX_2_6)
+# define INIT_ARCH()
 /* If the vDSO is not available we fall back to syscall.  */
 libc_ifunc_hidden (__gettimeofday_type, __gettimeofday,
-		   (_dl_vdso_vsym ("__vdso_gettimeofday", &linux26)
-		    ?: &__gettimeofday_syscall))
+		   (get_vdso_symbol ("__vdso_gettimeofday")
+		    ?: __gettimeofday_syscall));
 libc_hidden_def (__gettimeofday)
 
 #else
diff --git a/sysdeps/unix/sysv/linux/x86/time.c b/sysdeps/unix/sysv/linux/x86/time.c
index b114f148df..2e47661be3 100644
--- a/sysdeps/unix/sysv/linux/x86/time.c
+++ b/sysdeps/unix/sysv/linux/x86/time.c
@@ -22,6 +22,7 @@
 
 #include <dl-vdso.h>
 #include <errno.h>
+#include <sysdep-vdso.h>
 
 static time_t
 __time_syscall (time_t *t)
@@ -38,11 +39,10 @@ __time_syscall (time_t *t)
 # endif
 
 #undef INIT_ARCH
-#define INIT_ARCH() PREPARE_VERSION_KNOWN (linux26, LINUX_2_6);
+#define INIT_ARCH()
 /* If the vDSO is not available we fall back on the syscall.  */
 libc_ifunc_hidden (time_type, time,
-		   (_dl_vdso_vsym ("__vdso_time", &linux26)
-		    ?:  &__time_syscall))
+		   (get_vdso_symbol ("__vdso_time") ?: __time_syscall))
 libc_hidden_def (time)
 
 #else
diff --git a/sysdeps/unix/sysv/linux/x86_64/init-first.c b/sysdeps/unix/sysv/linux/x86_64/init-first.c
index 819dfbafc0..93c9ebbf4f 100644
--- a/sysdeps/unix/sysv/linux/x86_64/init-first.c
+++ b/sysdeps/unix/sysv/linux/x86_64/init-first.c
@@ -32,15 +32,13 @@ extern __typeof (clock_gettime) __syscall_clock_gettime attribute_hidden;
 static inline void
 __vdso_platform_setup (void)
 {
-  PREPARE_VERSION_KNOWN (linux26, LINUX_2_6);
-
-  void *p = _dl_vdso_vsym ("__vdso_clock_gettime", &linux26);
+  void *p = get_vdso_symbol ("__vdso_clock_gettime");
   if (p == NULL)
     p = __syscall_clock_gettime;
   PTR_MANGLE (p);
   VDSO_SYMBOL(clock_gettime) = p;
 
-  p = _dl_vdso_vsym ("__vdso_getcpu", &linux26);
+  p = get_vdso_symbol ("__vdso_getcpu");
   PTR_MANGLE (p);
   VDSO_SYMBOL(getcpu) = p;
 }
diff --git a/sysdeps/unix/sysv/linux/x86_64/sysdep.h b/sysdeps/unix/sysv/linux/x86_64/sysdep.h
index bad0a312e2..1ffb3cd65b 100644
--- a/sysdeps/unix/sysv/linux/x86_64/sysdep.h
+++ b/sysdeps/unix/sysv/linux/x86_64/sysdep.h
@@ -370,6 +370,9 @@
 # undef INTERNAL_SYSCALL_ERRNO
 # define INTERNAL_SYSCALL_ERRNO(val, err)	(-(val))
 
+# define VDSO_NAME  "LINUX_2.6"
+# define VDSO_HASH  61765110
+
 /* List of system calls which are supported as vsyscalls.  */
 # define HAVE_CLOCK_GETTIME_VSYSCALL    1
 # define HAVE_GETTIMEOFDAY_VSYSCALL     1