Refactor vDSO initialization code

Linux vDSO initialization code the internal function pointers require a
lot of duplicated boilerplate over different architectures.  This patch
aims to simplify not only the code but the required definition to enable
a vDSO symbol.

The changes are:

  1. Consolidate all init-first.c on only one implementation and enable
     the symbol based on HAVE_*_VSYSCALL existence.

  2. Set the HAVE_*_VSYSCALL to the architecture expected names string.

  3. Add a new internal implementation, get_vdso_mangle_symbol, which
     returns a mangled function pointer.

Currently the clock_gettime, clock_getres, gettimeofday, getcpu, and time
are handled in an arch-independent way, powerpc still uses some
arch-specific vDSO symbol handled in a specific init-first implementation.

Checked on aarch64-linux-gnu, arm-linux-gnueabihf, i386-linux-gnu,
mips64-linux-gnu, powerpc64le-linux-gnu, s390x-linux-gnu,
sparc64-linux-gnu, and x86_64-linux-gnu.

	* sysdeps/powerpc/powerpc32/backtrace.c (is_sigtramp_address,
	is_sigtramp_address_rt): Use HAVE_SIGTRAMP_{RT}32 instead of SHARED.
	* sysdeps/powerpc/powerpc64/backtrace.c (is_sigtramp_address):
	Likewise.
	* sysdeps/unix/sysv/linux/aarch64/init-first.c: Remove file.
	* sysdeps/unix/sysv/linux/aarch64/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/arm/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/arm/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/mips/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/mips/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/i386/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/riscv/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/riscv/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/s390/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/s390/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/sparc/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/sparc/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/x86/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/aarch64/sysdep.h
	(HAVE_CLOCK_GETRES_VSYSCALL, HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETTIMEOFDAY_VSYSCALL): Define value based on kernel exported
	name.
	* sysdeps/unix/sysv/linux/arm/sysdep.h (HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/i386/sysdep.h (HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/mips/sysdep.h (HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/sysdep.h
	(HAVE_CLOCK_GETRES_VSYSCALL, HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETCPU_VSYSCALL, HAVE_TIME_VSYSCALL, HAVE_GET_TBFREQ,
	HAVE_SIGTRAMP_RT64, HAVE_SIGTRAMP_32, HAVE_SIGTRAMP_RT32i,
	HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/riscv/sysdep.h (HAVE_CLOCK_GETRES_VSYSCALL,
	HAVE_CLOCK_GETTIME_VSYSCALL, HAVE_GETTIMEOFDAY_VSYSCALL,
	HAVE_GETCPU_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/s390/sysdep.h (HAVE_CLOCK_GETRES_VSYSCALL,
	HAVE_CLOCK_GETTIME_VSYSCALL, HAVE_GETTIMEOFDAY_VSYSCALL,
	HAVE_GETCPU_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/sparc/sysdep.h (HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/x86_64/sysdep.h
	(HAVE_CLOCK_GETTIME_VSYSCALL, HAVE_GETTIMEOFDAY_VSYSCALL,
	HAVE_GETCPU_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/dl-vdso.h (VDSO_NAME, VDSO_HASH): Define to
	invalid names if architecture does not define them.
	(get_vdso_mangle_symbol): New symbol.
	* sysdeps/unix/sysv/linux/init-first.c: New file.
	* sysdeps/unix/sysv/linux/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/init-first.c (gettimeofday,
	clock_gettime, clock_getres, getcpu, time): Remove declaration.
	(__libc_vdso_platform_setup_arch): Likewise and use
	get_vdso_mangle_symbol to setup vDSO symbols.
	(sigtramp_rt64, sigtramp32, sigtramp_rt32, get_tbfreq): Add
	attribute_hidden.
	* sysdeps/unix/sysv/linux/powerpc/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/sysdep-vdso.h (VDSO_SYMBOL): Remove
	definition.

1 files changed, 11 insertions, 40 deletions

diff --git a/sysdeps/unix/sysv/linux/powerpc/init-first.c b/sysdeps/unix/sysv/linux/powerpc/init-first.c
index b1618ed0b1..92a4af83af 100644
--- a/sysdeps/unix/sysv/linux/powerpc/init-first.c
+++ b/sysdeps/unix/sysv/linux/powerpc/init-first.c
@@ -19,47 +19,18 @@
 #include <dl-vdso.h>
 #include <libc-vdso.h>
 
-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 *);
-
+unsigned long long (*VDSO_SYMBOL(get_tbfreq)) (void) attribute_hidden;
 #if defined(__PPC64__) || defined(__powerpc64__)
-void *VDSO_SYMBOL(sigtramp_rt64);
+void *VDSO_SYMBOL(sigtramp_rt64) attribute_hidden;
 #else
-void *VDSO_SYMBOL(sigtramp32);
-void *VDSO_SYMBOL(sigtramp_rt32);
+void *VDSO_SYMBOL(sigtramp32) attribute_hidden;
+void *VDSO_SYMBOL(sigtramp_rt32) attribute_hidden;
 #endif
 
 static inline void
-_libc_vdso_platform_setup (void)
+__libc_vdso_platform_setup_arch (void)
 {
-  void *p = get_vdso_symbol ("__kernel_gettimeofday");
-  PTR_MANGLE (p);
-  VDSO_SYMBOL (gettimeofday) = p;
-
-  p = get_vdso_symbol ("__kernel_clock_gettime");
-  PTR_MANGLE (p);
-  VDSO_SYMBOL (clock_gettime) = p;
-
-  p = get_vdso_symbol ("__kernel_clock_getres");
-  PTR_MANGLE (p);
-  VDSO_SYMBOL (clock_getres) = p;
-
-  p = get_vdso_symbol ("__kernel_get_tbfreq");
-  PTR_MANGLE (p);
-  VDSO_SYMBOL (get_tbfreq) = p;
-
-  p = get_vdso_symbol ("__kernel_getcpu");
-  PTR_MANGLE (p);
-  VDSO_SYMBOL (getcpu) = p;
-
-  p = get_vdso_symbol ("__kernel_time");
-  PTR_MANGLE (p);
-  VDSO_SYMBOL (time) = p;
+  VDSO_SYMBOL (get_tbfreq) = get_vdso_mangle_symbol (HAVE_GET_TBFREQ);
 
   /* PPC64 uses only one signal trampoline symbol, while PPC32 will use
      two depending if SA_SIGINFO is used (__kernel_sigtramp_rt32) or not
@@ -67,13 +38,13 @@ _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) =  get_vdso_symbol ("__kernel_sigtramp_rt64");
+  VDSO_SYMBOL(sigtramp_rt64) =  get_vdso_symbol (HAVE_SIGTRAMP_RT64);
 #else
-  VDSO_SYMBOL(sigtramp32) = get_vdso_symbol ("__kernel_sigtramp32");
-  VDSO_SYMBOL(sigtramp_rt32) = get_vdso_symbol ("__kernel_sigtramp_rt32");
+  VDSO_SYMBOL(sigtramp32) = get_vdso_symbol (HAVE_SIGTRAMP_32);
+  VDSO_SYMBOL(sigtramp_rt32) = get_vdso_symbol (HAVE_SIGTRAMP_RT32);
 #endif
 }
 
-#define VDSO_SETUP _libc_vdso_platform_setup
+#define VDSO_SETUP_ARCH __libc_vdso_platform_setup_arch
 
-#include <csu/init-first.c>
+#include <sysdeps/unix/sysv/linux/init-first.c>