Use ifuncs for time and gettimeofday on x86-64

ChangeLog

@@ -1,3 +1,17 @@
+2011-08-21  Ulrich Drepper  <drepper@gmail.com>
+
+	* sysdeps/unix/sysv/linux/x86_64/gettimeofday.S: Removed.
+	* sysdeps/unix/sysv/linux/x86_64/time.S: Removed.
+	* sysdeps/unix/sysv/linux/x86_64/gettimeofday.c: New file.
+	* sysdeps/unix/sysv/linux/x86_64/time.c: New file.
+	* sysdeps/unix/sysv/linux/x86_64/bits/libc-vdso.h: Remove declaration
+	of __vdso_gettimeofday.
+	* sysdeps/unix/sysv/linux/x86_64/init-first.c: Remove definition of
+	__vdso_gettimeofday and __vdso_time.  Define __vdso_getcpu with
+	attribute_hidden.
+	(_libc_vdso_platform_setup): Remove initialization of
+	__vdso_gettimeofday and __vdso_time.
+
 2011-08-20  Ulrich Drepper  <drepper@gmail.com>
 
 	* nss/nss_files/files-alias.c (get_next_alias): Use feof_unlocked

sysdeps/unix/sysv/linux/x86_64/bits/libc-vdso.h

@@ -1,5 +1,5 @@
 /* Resolve function pointers to VDSO functions.
-   Copyright (C) 2005, 2007 Free Software Foundation, Inc.
+   Copyright (C) 2005, 2007, 2011 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
@@ -25,9 +25,6 @@
 
 #ifdef SHARED
 
-extern long int (*__vdso_gettimeofday) (struct timeval *, void *)
-  attribute_hidden;
-
 extern long int (*__vdso_clock_gettime) (clockid_t, struct timespec *);
 
 #endif

sysdeps/unix/sysv/linux/x86_64/gettimeofday.S → sysdeps/unix/sysv/linux/x86_64/gettimeofday.c

@@ -1,4 +1,4 @@
-/* Copyright (C) 2002, 2003, 2007 Free Software Foundation, Inc.
+/* Copyright (C) 2002, 2003, 2007, 2011 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
@@ -16,34 +16,34 @@
    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
    02111-1307 USA.  */
 
-#include <sysdep.h>
-#define _ERRNO_H	1
-#include <bits/errno.h>
+#include <dl-vdso.h>
 
-/* For the calculation see asm/vsyscall.h.  */
-#define VSYSCALL_ADDR_vgettimeofday	0xffffffffff600000
+
+#define VSYSCALL_ADDR_vgettimeofday	0xffffffffff600000ul
 
 
-ENTRY (__gettimeofday)
-	/* Align stack.  */
-	sub	$0x8, %rsp
-	cfi_adjust_cfa_offset(8)
 #ifdef SHARED
-	movq	__vdso_gettimeofday(%rip), %rax
-	PTR_DEMANGLE (%rax)
+void *gettimeofday_ifunc (void) __asm__ ("__gettimeofday");
+
+void *
+gettimeofday_ifunc (void)
+{
+  PREPARE_VERSION (linux26, "LINUX_2.6", 61765110);
+
+  /* If the vDSO is not available we fall back on the old vsyscall.  */
+  return (_dl_vdso_vsym ("gettimeofday", &linux26)
+	  ?: (void *) VSYSCALL_ADDR_vgettimeofday);
+}
+__asm (".type __gettimeofday, %gnu_indirect_function");
 #else
-	movq	$VSYSCALL_ADDR_vgettimeofday, %rax
-#endif
-	callq	*%rax
-	/* Check error return.  */
-	cmpl	$-4095, %eax
-	jae	SYSCALL_ERROR_LABEL
+# include <sys/time.h>
 
-L(pseudo_end):
-	add	$0x8, %rsp
-	cfi_adjust_cfa_offset(-8)
-	ret
-PSEUDO_END(__gettimeofday)
+int
+__gettimeofday (struct timeval *tv, struct timezone *tz)
+{
+  return ((int (*) (struct timeval *, struct timezone *)) VSYSCALL_ADDR_vgettimeofday) (tv, tz);
+}
+#endif
 
-strong_alias (__gettimeofday, __gettimeofday_internal)
 weak_alias (__gettimeofday, gettimeofday)
+strong_alias (__gettimeofday, __gettimeofday_internal)

sysdeps/unix/sysv/linux/x86_64/init-first.c

@@ -20,31 +20,19 @@
 # include <dl-vdso.h>
 # include <bits/libc-vdso.h>
 
-long int (*__vdso_gettimeofday) (struct timeval *, void *) attribute_hidden;
-
 long int (*__vdso_clock_gettime) (clockid_t, struct timespec *)
   __attribute__ ((nocommon));
 strong_alias (__vdso_clock_gettime, __GI___vdso_clock_gettime attribute_hidden)
 
-long int (*__vdso_getcpu) (unsigned *, unsigned *, void *);
-
-long int (*__vdso_time) (time_t *) attribute_hidden;
+long int (*__vdso_getcpu) (unsigned *, unsigned *, void *) attribute_hidden;
 
 
 static inline void
 _libc_vdso_platform_setup (void)
 {
   PREPARE_VERSION (linux26, "LINUX_2.6", 61765110);
 
-  void *p = _dl_vdso_vsym ("gettimeofday", &linux26);
-  /* If the vDSO is not available we fall back on the old vsyscall.  */
-#define VSYSCALL_ADDR_vgettimeofday	0xffffffffff600000ul
-  if (p == NULL)
-    p = (void *) VSYSCALL_ADDR_vgettimeofday;
-  PTR_MANGLE (p);
-  __vdso_gettimeofday = p;
-
-  p = _dl_vdso_vsym ("clock_gettime", &linux26);
+  void *p = _dl_vdso_vsym ("clock_gettime", &linux26);
   PTR_MANGLE (p);
   __GI___vdso_clock_gettime = p;
 
@@ -55,14 +43,6 @@ _libc_vdso_platform_setup (void)
     p = (void *) VSYSCALL_ADDR_vgetcpu;
   PTR_MANGLE (p);
   __vdso_getcpu = p;
-
-  p = _dl_vdso_vsym ("time", &linux26);
-  /* If the vDSO is not available we fall back on the old vsyscall.  */
-#define VSYSCALL_ADDR_vtime	0xffffffffff600400
-  if (p == NULL)
-    p = (void *) VSYSCALL_ADDR_vtime;
-  PTR_MANGLE (p);
-  __vdso_time = p;
 }
 
 # define VDSO_SETUP _libc_vdso_platform_setup

sysdeps/unix/sysv/linux/x86_64/time.S → sysdeps/unix/sysv/linux/x86_64/time.c

@@ -16,32 +16,32 @@
    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
    02111-1307 USA.  */
 
-#include <sysdep.h>
-#define _ERRNO_H	1
-#include <bits/errno.h>
+#include <dl-vdso.h>
+
 
-/* For the calculation see asm/vsyscall.h.  */
 #define VSYSCALL_ADDR_vtime	0xffffffffff600400
 
 
-/* Return the current time as a `time_t' and also put it in *T if T is
-   not NULL.  Time is represented as seconds from Jan 1 00:00:00 1970.  */
+#ifdef SHARED
+void *time_ifunc (void) __asm__ ("time");
 
-ENTRY (time)
-	/* Align stack.  */
-	sub	$0x8, %rsp
-	cfi_adjust_cfa_offset(8)
+void *
+time_ifunc (void)
+{
+  PREPARE_VERSION (linux26, "LINUX_2.6", 61765110);
 
-#ifdef SHARED
-	movq	__vdso_time(%rip), %rax
-	PTR_DEMANGLE (%rax)
+  /* If the vDSO is not available we fall back on the old vsyscall.  */
+  return _dl_vdso_vsym ("time", &linux26) ?: (void *) VSYSCALL_ADDR_vtime;
+}
+__asm (".type time, %gnu_indirect_function");
 #else
-	movq	$VSYSCALL_ADDR_vtime, %rax
+# include <time.h>
+
+time_t
+time (time_t *t)
+{
+  return ((time_t (*) (time_t *)) VSYSCALL_ADDR_vtime) (t);
+}
 #endif
-	callq	*%rax
 
-	add	$0x8, %rsp
-	cfi_adjust_cfa_offset(-8)
-	ret
-PSEUDO_END_NOERRNO(time)
-libc_hidden_def (time)
+strong_alias (time, __GI_time)