diff options
Diffstat (limited to 'src/third_party/gperftools-2.5/src/base/vdso_support.h')
| -rw-r--r-- | src/third_party/gperftools-2.5/src/base/vdso_support.h | 132 |
1 files changed, 0 insertions, 132 deletions
diff --git a/src/third_party/gperftools-2.5/src/base/vdso_support.h b/src/third_party/gperftools-2.5/src/base/vdso_support.h deleted file mode 100644 index c1209a47f13..00000000000 --- a/src/third_party/gperftools-2.5/src/base/vdso_support.h +++ /dev/null @@ -1,132 +0,0 @@ -// Copyright (c) 2008, Google Inc. -// All rights reserved. -// -// Redistribution and use in source and binary forms, with or without -// modification, are permitted provided that the following conditions are -// met: -// -// * Redistributions of source code must retain the above copyright -// notice, this list of conditions and the following disclaimer. -// * Redistributions in binary form must reproduce the above -// copyright notice, this list of conditions and the following disclaimer -// in the documentation and/or other materials provided with the -// distribution. -// * Neither the name of Google Inc. nor the names of its -// contributors may be used to endorse or promote products derived from -// this software without specific prior written permission. -// -// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS -// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT -// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR -// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT -// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, -// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT -// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, -// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY -// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT -// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE -// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - -// --- -// Author: Paul Pluzhnikov -// -// Allow dynamic symbol lookup in the kernel VDSO page. -// -// VDSO stands for "Virtual Dynamic Shared Object" -- a page of -// executable code, which looks like a shared library, but doesn't -// necessarily exist anywhere on disk, and which gets mmap()ed into -// every process by kernels which support VDSO, such as 2.6.x for 32-bit -// executables, and 2.6.24 and above for 64-bit executables. -// -// More details could be found here: -// http://www.trilithium.com/johan/2005/08/linux-gate/ -// -// VDSOSupport -- a class representing kernel VDSO (if present). -// -// Example usage: -// VDSOSupport vdso; -// VDSOSupport::SymbolInfo info; -// typedef (*FN)(unsigned *, void *, void *); -// FN fn = NULL; -// if (vdso.LookupSymbol("__vdso_getcpu", "LINUX_2.6", STT_FUNC, &info)) { -// fn = reinterpret_cast<FN>(info.address); -// } - -#ifndef BASE_VDSO_SUPPORT_H_ -#define BASE_VDSO_SUPPORT_H_ - -#include <config.h> -#include "base/basictypes.h" -#include "base/elf_mem_image.h" - -#ifdef HAVE_ELF_MEM_IMAGE - -#define HAVE_VDSO_SUPPORT 1 - -#include <stdlib.h> // for NULL - -namespace base { - -// NOTE: this class may be used from within tcmalloc, and can not -// use any memory allocation routines. -class VDSOSupport { - public: - VDSOSupport(); - - typedef ElfMemImage::SymbolInfo SymbolInfo; - typedef ElfMemImage::SymbolIterator SymbolIterator; - - // Answers whether we have a vdso at all. - bool IsPresent() const { return image_.IsPresent(); } - - // Allow to iterate over all VDSO symbols. - SymbolIterator begin() const { return image_.begin(); } - SymbolIterator end() const { return image_.end(); } - - // Look up versioned dynamic symbol in the kernel VDSO. - // Returns false if VDSO is not present, or doesn't contain given - // symbol/version/type combination. - // If info_out != NULL, additional details are filled in. - bool LookupSymbol(const char *name, const char *version, - int symbol_type, SymbolInfo *info_out) const; - - // Find info about symbol (if any) which overlaps given address. - // Returns true if symbol was found; false if VDSO isn't present - // or doesn't have a symbol overlapping given address. - // If info_out != NULL, additional details are filled in. - bool LookupSymbolByAddress(const void *address, SymbolInfo *info_out) const; - - // Used only for testing. Replace real VDSO base with a mock. - // Returns previous value of vdso_base_. After you are done testing, - // you are expected to call SetBase() with previous value, in order to - // reset state to the way it was. - const void *SetBase(const void *s); - - // Computes vdso_base_ and returns it. Should be called as early as - // possible; before any thread creation, chroot or setuid. - static const void *Init(); - - private: - // image_ represents VDSO ELF image in memory. - // image_.ehdr_ == NULL implies there is no VDSO. - ElfMemImage image_; - - // Cached value of auxv AT_SYSINFO_EHDR, computed once. - // This is a tri-state: - // kInvalidBase => value hasn't been determined yet. - // 0 => there is no VDSO. - // else => vma of VDSO Elf{32,64}_Ehdr. - // - // When testing with mock VDSO, low bit is set. - // The low bit is always available because vdso_base_ is - // page-aligned. - static const void *vdso_base_; - - DISALLOW_COPY_AND_ASSIGN(VDSOSupport); -}; - -} // namespace base - -#endif // HAVE_ELF_MEM_IMAGE - -#endif // BASE_VDSO_SUPPORT_H_ |