Mercurial > hg > graal-compiler
view src/share/vm/utilities/elfFile.cpp @ 2149:7e37af9d69ef
7011379: G1: overly long concurrent marking cycles
Summary: This changeset introduces filtering of SATB buffers at the point when they are about to be enqueued. If this filtering clears enough entries on each buffer, the buffer can then be re-used and not enqueued. This cuts down the number of SATB buffers that need to be processed by the concurrent marking threads.
Reviewed-by: johnc, ysr
author | tonyp |
---|---|
date | Wed, 19 Jan 2011 09:35:17 -0500 |
parents | 2d4762ec74af |
children | 2a3da7eaf4a6 |
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/* * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #include "precompiled.hpp" #ifndef _WINDOWS #include <string.h> #include <stdio.h> #include <limits.h> #include "memory/allocation.inline.hpp" #include "utilities/decoder.hpp" #include "utilities/elfFile.hpp" #include "utilities/elfStringTable.hpp" #include "utilities/elfSymbolTable.hpp" ElfFile::ElfFile(const char* filepath) { assert(filepath, "null file path"); memset(&m_elfHdr, 0, sizeof(m_elfHdr)); m_string_tables = NULL; m_symbol_tables = NULL; m_next = NULL; m_status = Decoder::no_error; int len = strlen(filepath) + 1; m_filepath = NEW_C_HEAP_ARRAY(char, len); if (m_filepath != NULL) { strcpy((char*)m_filepath, filepath); m_file = fopen(filepath, "r"); if (m_file != NULL) { load_tables(); } else { m_status = Decoder::file_not_found; } } else { m_status = Decoder::out_of_memory; } } ElfFile::~ElfFile() { if (m_string_tables != NULL) { delete m_string_tables; } if (m_symbol_tables != NULL) { delete m_symbol_tables; } if (m_file != NULL) { fclose(m_file); } if (m_filepath != NULL) { FREE_C_HEAP_ARRAY(char, m_filepath); } if (m_next != NULL) { delete m_next; } }; //Check elf header to ensure the file is valid. bool ElfFile::is_elf_file(Elf_Ehdr& hdr) { return (ELFMAG0 == hdr.e_ident[EI_MAG0] && ELFMAG1 == hdr.e_ident[EI_MAG1] && ELFMAG2 == hdr.e_ident[EI_MAG2] && ELFMAG3 == hdr.e_ident[EI_MAG3] && ELFCLASSNONE != hdr.e_ident[EI_CLASS] && ELFDATANONE != hdr.e_ident[EI_DATA]); } bool ElfFile::load_tables() { assert(m_file, "file not open"); assert(m_status == Decoder::no_error, "already in error"); // read elf file header if (fread(&m_elfHdr, sizeof(m_elfHdr), 1, m_file) != 1) { m_status = Decoder::file_invalid; return false; } if (!is_elf_file(m_elfHdr)) { m_status = Decoder::file_invalid; return false; } // walk elf file's section headers, and load string tables Elf_Shdr shdr; if (!fseek(m_file, m_elfHdr.e_shoff, SEEK_SET)) { if (m_status != Decoder::no_error) return false; for (int index = 0; index < m_elfHdr.e_shnum; index ++) { if (fread((void*)&shdr, sizeof(Elf_Shdr), 1, m_file) != 1) { m_status = Decoder::file_invalid; return false; } // string table if (shdr.sh_type == SHT_STRTAB) { ElfStringTable* table = new ElfStringTable(m_file, shdr, index); if (table == NULL) { m_status = Decoder::out_of_memory; return false; } add_string_table(table); } else if (shdr.sh_type == SHT_SYMTAB || shdr.sh_type == SHT_DYNSYM) { ElfSymbolTable* table = new ElfSymbolTable(m_file, shdr); if (table == NULL) { m_status = Decoder::out_of_memory; return false; } add_symbol_table(table); } } } return true; } const char* ElfFile::decode(address addr, int* offset) { // something already went wrong, just give up if (m_status != Decoder::no_error) { return NULL; } ElfSymbolTable* symbol_table = m_symbol_tables; int string_table_index; int pos_in_string_table; int off = INT_MAX; bool found_symbol = false; while (symbol_table != NULL) { if (Decoder::no_error == symbol_table->lookup(addr, &string_table_index, &pos_in_string_table, &off)) { found_symbol = true; } symbol_table = symbol_table->m_next; } if (!found_symbol) return NULL; ElfStringTable* string_table = get_string_table(string_table_index); if (string_table == NULL) { m_status = Decoder::file_invalid; return NULL; } if (offset) *offset = off; return string_table->string_at(pos_in_string_table); } void ElfFile::add_symbol_table(ElfSymbolTable* table) { if (m_symbol_tables == NULL) { m_symbol_tables = table; } else { table->m_next = m_symbol_tables; m_symbol_tables = table; } } void ElfFile::add_string_table(ElfStringTable* table) { if (m_string_tables == NULL) { m_string_tables = table; } else { table->m_next = m_string_tables; m_string_tables = table; } } ElfStringTable* ElfFile::get_string_table(int index) { ElfStringTable* p = m_string_tables; while (p != NULL) { if (p->index() == index) return p; p = p->m_next; } return NULL; } #endif // _WINDOWS