1/*
2 * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24#include "precompiled.hpp"
25#include <string.h>
26#include "utilities/globalDefinitions.hpp"
27#include <sstream>
28#include "gc/shared/memset_with_concurrent_readers.hpp"
29#include "unittest.hpp"
30
31#if INCLUDE_ALL_GCS
32
33static unsigned line_byte(const char* line, size_t i) {
34  return unsigned(line[i]) & 0xFF;
35}
36
37TEST(gc, memset_with_concurrent_readers) {
38  const size_t chunk_size = 8 * BytesPerWord;
39  const unsigned chunk_count = 4;
40  const size_t block_size = (chunk_count + 4) * chunk_size;
41  char block[block_size];
42  char clear_block[block_size];
43  char set_block[block_size];
44
45  // block format:
46  // 0: unused leading chunk
47  // 1: chunk written from start index to end of chunk
48  // ... nchunks fully written chunks
49  // N: chunk written from start of chunk to end index
50  // N+1: unused trailing chunk
51
52  const int clear_value = 0;
53  const int set_value = 0xAC;
54
55  memset(clear_block, clear_value, block_size);
56  memset(set_block, set_value, block_size);
57
58  for (unsigned nchunks = 0; nchunks <= chunk_count; ++nchunks) {
59    for (size_t start = 1; start <= chunk_size; ++start) {
60      for (size_t end = 0; end <= chunk_size; ++end) {
61        size_t set_start = chunk_size + start;
62        size_t set_end = (2 + nchunks) * chunk_size + end;
63        size_t set_size = set_end - set_start;
64
65        memset(block, clear_value, block_size);
66        memset_with_concurrent_readers(&block[set_start], set_value, set_size);
67        bool head_clear = !memcmp(clear_block, block, set_start);
68        bool middle_set = !memcmp(set_block, block + set_start, set_size);
69        bool tail_clear = !memcmp(clear_block, block + set_end, block_size - set_end);
70        if (!(head_clear && middle_set && tail_clear)) {
71          std::ostringstream err_stream;
72          err_stream << "*** memset_with_concurrent_readers failed: set start "
73                     << set_start << ", set end " << set_end << std::endl;
74          for (unsigned chunk = 0; chunk < (block_size / chunk_size); ++chunk) {
75            for (unsigned line = 0; line < (chunk_size / BytesPerWord); ++line) {
76
77              const char* lp = &block[chunk * chunk_size + line * BytesPerWord];
78
79              err_stream << std::dec << chunk << "," << line << ": " << std::hex
80                         << std::setw(2) << line_byte(lp, 0) << " "
81                         << std::setw(2) << line_byte(lp, 1) << "  "
82                         << std::setw(2) << line_byte(lp, 2) << " "
83                         << std::setw(2) << line_byte(lp, 3) << "  "
84                         << std::setw(2) << line_byte(lp, 4) << " "
85                         << std::setw(2) << line_byte(lp, 5) << "  "
86                         << std::setw(2) << line_byte(lp, 6) << " "
87                         << std::setw(2) << line_byte(lp, 7) << std::endl;
88            }
89          }
90          EXPECT_TRUE(head_clear) << "leading byte not clear";
91          EXPECT_TRUE(middle_set) << "memset byte not set";
92          EXPECT_TRUE(tail_clear) << "trailing bye not clear";
93          ASSERT_TRUE(head_clear && middle_set && tail_clear) << err_stream.str();
94        }
95      }
96    }
97  }
98}
99#endif
100