jdk

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/*
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 * Copyright (c) 2018, 2019, Oracle and/or its affiliates. All rights reserved.
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
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 * This code is free software; you can redistribute it and/or modify it
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 * under the terms of the GNU General Public License version 2 only, as
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 * published by the Free Software Foundation.
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 *
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 * This code is distributed in the hope that it will be useful, but WITHOUT
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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 * version 2 for more details (a copy is included in the LICENSE file that
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 * accompanied this code).
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 *
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 * You should have received a copy of the GNU General Public License version
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 * 2 along with this work; if not, write to the Free Software Foundation,
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 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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 *
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 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 * or visit www.oracle.com if you need additional information or have any
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 * questions.
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 */
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#include "precompiled.hpp"
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#include "memory/allocation.hpp"
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#include "runtime/synchronizer.hpp"
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#include "runtime/vm_version.hpp"
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#include "unittest.hpp"
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class SynchronizerTest : public ::testing::Test {
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  public:
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    static u_char* get_gvars_addr() { return ObjectSynchronizer::get_gvars_addr(); }
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    static u_char* get_gvars_hc_sequence_addr() { return ObjectSynchronizer::get_gvars_hc_sequence_addr(); }
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    static size_t get_gvars_size() { return ObjectSynchronizer::get_gvars_size(); }
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    static u_char* get_gvars_stw_random_addr() { return ObjectSynchronizer::get_gvars_stw_random_addr(); }
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};
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TEST_VM(SynchronizerTest, sanity) {
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  uint cache_line_size = VM_Version::L1_data_cache_line_size();
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  if (cache_line_size != 0) {
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    // We were able to determine the L1 data cache line size so
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    // do some cache line specific sanity checks
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    u_char *addr_begin = SynchronizerTest::get_gvars_addr();
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    u_char *addr_stw_random = SynchronizerTest::get_gvars_stw_random_addr();
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    u_char *addr_hc_sequence = SynchronizerTest::get_gvars_hc_sequence_addr();
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    size_t gvars_size = SynchronizerTest::get_gvars_size();
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    uint offset_stw_random = (uint) (addr_stw_random - addr_begin);
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    uint offset_hc_sequence = (uint) (addr_hc_sequence - addr_begin);
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    uint offset_hc_sequence_stw_random = offset_hc_sequence - offset_stw_random;
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    uint offset_hc_sequence_struct_end = (uint) gvars_size - offset_hc_sequence;
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    EXPECT_GE(offset_stw_random, cache_line_size)
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            << "the SharedGlobals.stw_random field is closer "
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            << "to the struct beginning than a cache line which permits "
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            << "false sharing.";
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    EXPECT_GE(offset_hc_sequence_stw_random, cache_line_size)
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            << "the SharedGlobals.stw_random and "
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            << "SharedGlobals.hc_sequence fields are closer than a cache "
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            << "line which permits false sharing.";
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    EXPECT_GE(offset_hc_sequence_struct_end, cache_line_size)
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            << "the SharedGlobals.hc_sequence field is closer "
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            << "to the struct end than a cache line which permits false "
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            << "sharing.";
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  }
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}
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