aoqi@0: /*
aoqi@0:  * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  *
aoqi@0:  */
aoqi@0: 
aoqi@0: #include "precompiled.hpp"
aoqi@0: #include "memory/resourceArea.hpp"
aoqi@0: #include "runtime/icache.hpp"
aoqi@0: 
aoqi@0: // The flush stub function address
aoqi@0: AbstractICache::flush_icache_stub_t AbstractICache::_flush_icache_stub = NULL;
aoqi@0: 
aoqi@0: void AbstractICache::initialize() {
aoqi@0:   // Making this stub must be FIRST use of assembler
aoqi@0:   ResourceMark rm;
aoqi@0: 
aoqi@0:   BufferBlob* b = BufferBlob::create("flush_icache_stub", ICache::stub_size);
aoqi@0:   CodeBuffer c(b);
aoqi@0: 
aoqi@0:   ICacheStubGenerator g(&c);
aoqi@0:   g.generate_icache_flush(&_flush_icache_stub);
aoqi@0: 
aoqi@0:   // The first use of flush_icache_stub must apply it to itself.
aoqi@0:   // The StubCodeMark destructor in generate_icache_flush will
aoqi@0:   // call Assembler::flush, which in turn will call invalidate_range,
aoqi@0:   // which will in turn call the flush stub.  Thus we don't need an
aoqi@0:   // explicit call to invalidate_range here.  This assumption is
aoqi@0:   // checked in invalidate_range.
aoqi@0: }
aoqi@0: 
aoqi@0: void AbstractICache::call_flush_stub(address start, int lines) {
aoqi@0:   // The business with the magic number is just a little security.
aoqi@0:   // We cannot call the flush stub when generating the flush stub
aoqi@0:   // because it isn't there yet.  So, the stub also returns its third
aoqi@0:   // parameter.  This is a cheap check that the stub was really executed.
aoqi@0:   static int magic = 0xbaadbabe;
aoqi@0: 
aoqi@0:   int auto_magic = magic; // Make a local copy to avoid race condition
aoqi@0:   int r = (*_flush_icache_stub)(start, lines, auto_magic);
aoqi@0:   guarantee(r == auto_magic, "flush stub routine did not execute");
aoqi@0:   ++magic;
aoqi@0: }
aoqi@0: 
aoqi@0: void AbstractICache::invalidate_word(address addr) {
aoqi@0:   // Because this is called for instruction patching on the fly, long after
aoqi@0:   // bootstrapping, we execute the stub directly.  Account for a 4-byte word
aoqi@0:   // spanning two cache lines by computing a start line address by rounding
aoqi@0:   // addr down to a line_size boundary, and an end line address by adding
aoqi@0:   // the word size - 1 and rounding the result down to a line_size boundary.
aoqi@0:   // If we just added word size, we'd mistakenly flush the next cache line
aoqi@0:   // if the word to be flushed started in the last 4 bytes of the line.
aoqi@0:   // Doing that would segv if the next line weren't mapped.
aoqi@0: 
aoqi@0:   const int word_size_in_bytes = 4; // Always, regardless of platform
aoqi@0: 
aoqi@0:   intptr_t start_line = ((intptr_t)addr + 0) & ~(ICache::line_size - 1);
aoqi@0:   intptr_t end_line   = ((intptr_t)addr + word_size_in_bytes - 1)
aoqi@0:                                              & ~(ICache::line_size - 1);
aoqi@0:   (*_flush_icache_stub)((address)start_line, start_line == end_line ? 1 : 2, 0);
aoqi@0: }
aoqi@0: 
aoqi@0: void AbstractICache::invalidate_range(address start, int nbytes) {
aoqi@0:   static bool firstTime = true;
aoqi@0:   if (firstTime) {
aoqi@0:     guarantee(start == CAST_FROM_FN_PTR(address, _flush_icache_stub),
aoqi@0:               "first flush should be for flush stub");
aoqi@0:     firstTime = false;
aoqi@0:     return;
aoqi@0:   }
aoqi@0:   if (nbytes == 0) {
aoqi@0:     return;
aoqi@0:   }
aoqi@0:   // Align start address to an icache line boundary and transform
aoqi@0:   // nbytes to an icache line count.
aoqi@0:   const uint line_offset = mask_address_bits(start, ICache::line_size-1);
aoqi@0:   if (line_offset != 0) {
aoqi@0:     start -= line_offset;
aoqi@0:     nbytes += line_offset;
aoqi@0:   }
aoqi@0:   call_flush_stub(start, round_to(nbytes, ICache::line_size) >>
aoqi@0:                          ICache::log2_line_size);
aoqi@0: }
aoqi@0: 
aoqi@0: // For init.cpp
aoqi@0: void icache_init() {
aoqi@0:   ICache::initialize();
aoqi@0: }