From c738465a4c13370f58b797a82cdf1c67e1121867 Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Sat, 28 May 2011 01:53:26 -0400 Subject: [PATCH] Add support for time syscall in vDSO --- ChangeLog | 6 ++++++ sysdeps/unix/sysv/linux/x86_64/init-first.c | 10 ++++++++++ sysdeps/unix/sysv/linux/x86_64/time.S | 7 ++++++- 3 files changed, 22 insertions(+), 1 deletion(-) diff --git a/ChangeLog b/ChangeLog index 1f474df..188fc90 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,11 @@ 2011-05-28 Ulrich Drepper + [BZ #12813] + * sysdeps/unix/sysv/linux/x86_64/init-first.c (__vdso_time): Retrieve + time symbol from vDSO. Substitute with vsyscall if not available. + * sysdeps/unix/sysv/linux/x86_64/time.S [SHARED]: Use + __vdso_time. + * sysdeps/unix/sysv/linux/internal_sendmmsg.S: New file. * sysdeps/unix/sysv/linux/sendmmsg.c: New file. * sysdeps/unix/sysv/linux/Makefile [subdir=socket] (sysdep_routines): diff --git a/sysdeps/unix/sysv/linux/x86_64/init-first.c b/sysdeps/unix/sysv/linux/x86_64/init-first.c index 23934fc..e676f62 100644 --- a/sysdeps/unix/sysv/linux/x86_64/init-first.c +++ b/sysdeps/unix/sysv/linux/x86_64/init-first.c @@ -28,6 +28,8 @@ 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; + static inline void _libc_vdso_platform_setup (void) @@ -53,6 +55,14 @@ _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 diff --git a/sysdeps/unix/sysv/linux/x86_64/time.S b/sysdeps/unix/sysv/linux/x86_64/time.S index e3f3268..66d7498 100644 --- a/sysdeps/unix/sysv/linux/x86_64/time.S +++ b/sysdeps/unix/sysv/linux/x86_64/time.S @@ -1,4 +1,4 @@ -/* Copyright (C) 2001,02, 2003 Free Software Foundation, Inc. +/* Copyright (C) 2001,02, 2003, 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 @@ -32,7 +32,12 @@ ENTRY (time) sub $0x8, %rsp cfi_adjust_cfa_offset(8) +#ifdef SHARED + movq __vdso_time(%rip), %rax + PTR_DEMANGLE (%rax) +#else movq $VSYSCALL_ADDR_vtime, %rax +#endif callq *%rax add $0x8, %rsp -- 2.7.4