| /* |
| * 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" |
| #include "memory/resourceArea.hpp" |
| #include "runtime/icache.hpp" |
| #include "utilities/align.hpp" |
| |
| // The flush stub function address |
| AbstractICache::flush_icache_stub_t AbstractICache::_flush_icache_stub = NULL; |
| |
| void AbstractICache::initialize() { |
| // Making this stub must be FIRST use of assembler |
| ResourceMark rm; |
| |
| BufferBlob* b = BufferBlob::create("flush_icache_stub", ICache::stub_size); |
| if (b == NULL) { |
| vm_exit_out_of_memory(ICache::stub_size, OOM_MALLOC_ERROR, "CodeCache: no space for flush_icache_stub"); |
| } |
| CodeBuffer c(b); |
| |
| ICacheStubGenerator g(&c); |
| g.generate_icache_flush(&_flush_icache_stub); |
| |
| // The first use of flush_icache_stub must apply it to itself. |
| // The StubCodeMark destructor in generate_icache_flush will |
| // call Assembler::flush, which in turn will call invalidate_range, |
| // which will in turn call the flush stub. Thus we don't need an |
| // explicit call to invalidate_range here. This assumption is |
| // checked in invalidate_range. |
| } |
| |
| void AbstractICache::call_flush_stub(address start, int lines) { |
| // The business with the magic number is just a little security. |
| // We cannot call the flush stub when generating the flush stub |
| // because it isn't there yet. So, the stub also returns its third |
| // parameter. This is a cheap check that the stub was really executed. |
| static int magic = 0xbaadbabe; |
| |
| int auto_magic = magic; // Make a local copy to avoid race condition |
| int r = (*_flush_icache_stub)(start, lines, auto_magic); |
| guarantee(r == auto_magic, "flush stub routine did not execute"); |
| ++magic; |
| } |
| |
| void AbstractICache::invalidate_word(address addr) { |
| // Because this is called for instruction patching on the fly, long after |
| // bootstrapping, we execute the stub directly. Account for a 4-byte word |
| // spanning two cache lines by computing a start line address by rounding |
| // addr down to a line_size boundary, and an end line address by adding |
| // the word size - 1 and rounding the result down to a line_size boundary. |
| // If we just added word size, we'd mistakenly flush the next cache line |
| // if the word to be flushed started in the last 4 bytes of the line. |
| // Doing that would segv if the next line weren't mapped. |
| |
| const int word_size_in_bytes = 4; // Always, regardless of platform |
| |
| intptr_t start_line = ((intptr_t)addr + 0) & ~(ICache::line_size - 1); |
| intptr_t end_line = ((intptr_t)addr + word_size_in_bytes - 1) |
| & ~(ICache::line_size - 1); |
| (*_flush_icache_stub)((address)start_line, start_line == end_line ? 1 : 2, 0); |
| } |
| |
| void AbstractICache::invalidate_range(address start, int nbytes) { |
| static bool firstTime = true; |
| if (firstTime) { |
| guarantee(start == CAST_FROM_FN_PTR(address, _flush_icache_stub), |
| "first flush should be for flush stub"); |
| firstTime = false; |
| return; |
| } |
| if (nbytes == 0) { |
| return; |
| } |
| // Align start address to an icache line boundary and transform |
| // nbytes to an icache line count. |
| const uint line_offset = mask_address_bits(start, ICache::line_size-1); |
| if (line_offset != 0) { |
| start -= line_offset; |
| nbytes += line_offset; |
| } |
| call_flush_stub(start, align_up(nbytes, (int)ICache::line_size) >> |
| ICache::log2_line_size); |
| } |
| |
| // For init.cpp |
| void icache_init() { |
| ICache::initialize(); |
| } |