libc/src/__support/OSUtil/linux/x86_64/vdso.h

   1 //===---------- x86/x86_64 vdso configuration ---------------------* C++ *-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 #ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_X86_64_VDSO_H
   9 #define LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_X86_64_VDSO_H
  10 #include "src/__support/CPP/string_view.h"
  11 #include "src/__support/OSUtil/linux/vdso_sym.h"
  12 namespace LIBC_NAMESPACE_DECL {
  13 namespace vdso {
  14 // translate VDSOSym to symbol names
  15 // On x86, there are symbols defined without the __vdso_ prefix, however,
  16 // it is suggested that one should use the __vdso_ prefix.
  17 // Additionally, there is also an __vdso_sgx_enter_enclave, it is for the SGX
  18 // support, we do not include it here for now.
  19 // https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/x86/entry/vdso/vdso.lds.S
  20 LIBC_INLINE constexpr cpp::string_view symbol_name(VDSOSym sym) {
  21   switch (sym) {
  22   case VDSOSym::ClockGetTime:
  23     return "__vdso_clock_gettime";
  24   case VDSOSym::GetTimeOfDay:
  25     return "__vdso_gettimeofday";
  26   case VDSOSym::GetCpu:
  27     return "__vdso_getcpu";
  28   case VDSOSym::Time:
  29     return "__vdso_time";
  30   case VDSOSym::ClockGetRes:
  31     return "__vdso_clock_getres";
  32   default:
  33     return "";
  34   }
  35 }
  36
  37 // symbol versions
  38 LIBC_INLINE constexpr cpp::string_view symbol_version(VDSOSym) {
  39   return "LINUX_2.6";
  40 }
  41 } // namespace vdso
  42 } // namespace LIBC_NAMESPACE_DECL
  43 #endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_X86_64_VDSO_H