Consolidate vDSO macros and usage

This patch consolidate the Linux vDSO define and usage across all ports
that uses it.  The common vDSO definitions and calling through
{INLINE/INTERNAL}_VSYSCALL macros are moved to a common header
sysdep-vdso.h and vDSO name declaration and prototype is defined
using a common macro.

Also PTR_{MANGLE,DEMANGLE} is added to ports that does not use them
for vDSO calls (aarch64, powerpc, s390, and tile) and thus it will
reflect in code changes.  For ports that already implement pointer
mangling/demangling in vDSO system (i386, x32, x86_64) this patch
is mainly a code refactor.

Checked on x32, x86_64, x32, ppc64le, and aarch64.

1 files changed, 37 insertions, 19 deletions

diff --git a/sysdeps/unix/sysv/linux/powerpc/init-first.c b/sysdeps/unix/sysv/linux/powerpc/init-first.c
index b4917d12a5..ee91c0bf9e 100644
--- a/sysdeps/unix/sysv/linux/powerpc/init-first.c
+++ b/sysdeps/unix/sysv/linux/powerpc/init-first.c
@@ -23,17 +23,19 @@
 # undef __clock_getres
 # include <libc-vdso.h>
 
-void *__vdso_gettimeofday attribute_hidden;
-void *__vdso_clock_gettime;
-void *__vdso_clock_getres;
-void *__vdso_get_tbfreq;
-void *__vdso_getcpu;
-void *__vdso_time;
+int (*VDSO_SYMBOL(gettimeofday)) (struct timeval *, void *)
+  attribute_hidden;
+int (*VDSO_SYMBOL(clock_gettime)) (clockid_t, struct timespec *);
+int (*VDSO_SYMBOL(clock_getres)) (clockid_t, struct timespec *);
+unsigned long long (*VDSO_SYMBOL(get_tbfreq)) (void);
+int (*VDSO_SYMBOL(getcpu)) (unsigned *, unsigned *);
+time_t (*VDSO_SYMBOL(time)) (time_t *);
+
 #if defined(__PPC64__) || defined(__powerpc64__)
-void *__vdso_sigtramp_rt64;
+void *VDSO_SYMBOL(sigtramp_rt64);
 #else
-void *__vdso_sigtramp32;
-void *__vdso_sigtramp_rt32;
+void *VDSO_SYMBOL(sigtramp32);
+void *VDSO_SYMBOL(sigtramp_rt32);
 #endif
 
 static inline void
@@ -41,26 +43,42 @@ _libc_vdso_platform_setup (void)
 {
   PREPARE_VERSION (linux2615, "LINUX_2.6.15", 123718565);
 
-  __vdso_gettimeofday = _dl_vdso_vsym ("__kernel_gettimeofday", &linux2615);
+  void *p = _dl_vdso_vsym ("__kernel_gettimeofday", &linux2615);
+  PTR_MANGLE (p);
+  VDSO_SYMBOL (gettimeofday) = p;
 
-  __vdso_clock_gettime = _dl_vdso_vsym ("__kernel_clock_gettime", &linux2615);
+  p = _dl_vdso_vsym ("__kernel_clock_gettime", &linux2615);
+  PTR_MANGLE (p);
+  VDSO_SYMBOL (clock_gettime) = p;
 
-  __vdso_clock_getres = _dl_vdso_vsym ("__kernel_clock_getres", &linux2615);
+  p = _dl_vdso_vsym ("__kernel_clock_getres", &linux2615);
+  PTR_MANGLE (p);
+  VDSO_SYMBOL (clock_getres) = p;
 
-  __vdso_get_tbfreq = _dl_vdso_vsym ("__kernel_get_tbfreq", &linux2615);
+  p = _dl_vdso_vsym ("__kernel_get_tbfreq", &linux2615);
+  PTR_MANGLE (p);
+  VDSO_SYMBOL (get_tbfreq) = p;
 
-  __vdso_getcpu = _dl_vdso_vsym ("__kernel_getcpu", &linux2615);
+  p = _dl_vdso_vsym ("__kernel_getcpu", &linux2615);
+  PTR_MANGLE (p);
+  VDSO_SYMBOL (getcpu) = p;
 
-  __vdso_time = _dl_vdso_vsym ("__kernel_time", &linux2615);
+  p = _dl_vdso_vsym ("__kernel_time", &linux2615);
+  PTR_MANGLE (p);
+  VDSO_SYMBOL (time) = p;
 
   /* PPC64 uses only one signal trampoline symbol, while PPC32 will use
      two depending if SA_SIGINFO is used (__kernel_sigtramp_rt32) or not
-     (__kernel_sigtramp32).  */
+     (__kernel_sigtramp32).
+     There is no need to pointer mangle these symbol because they will
+     used only for pointer comparison.  */
 #if defined(__PPC64__) || defined(__powerpc64__)
-  __vdso_sigtramp_rt64 = _dl_vdso_vsym ("__kernel_sigtramp_rt64", &linux2615);
+  VDSO_SYMBOL(sigtramp_rt64) = _dl_vdso_vsym ("__kernel_sigtramp_rt64",
+					      &linux2615);
 #else
-  __vdso_sigtramp32 = _dl_vdso_vsym ("__kernel_sigtramp32", &linux2615);
-  __vdso_sigtramp_rt32 = _dl_vdso_vsym ("__kernel_sigtramp_rt32", &linux2615);
+  VDSO_SYMBOL(sigtramp32) = _dl_vdso_vsym ("__kernel_sigtramp32", &linux2615);
+  VDSO_SYMBOL(sigtramp_rt32) = _dl_vdso_vsym ("__kernel_sigtramp_rt32",
+					      &linux2615);
 #endif
 }