1 /*
2  * Copyright (C) 2017 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "perfetto/ext/tracing/core/shared_memory_abi.h"
18 
19 #include "perfetto/ext/tracing/core/basic_types.h"
20 #include "src/base/test/gtest_test_suite.h"
21 #include "src/tracing/test/aligned_buffer_test.h"
22 #include "test/gtest_and_gmock.h"
23 
24 namespace perfetto {
25 namespace {
26 
27 using testing::ValuesIn;
28 using Chunk = SharedMemoryABI::Chunk;
29 using ChunkHeader = SharedMemoryABI::ChunkHeader;
30 
31 using SharedMemoryABITest = AlignedBufferTest;
32 
33 size_t const kPageSizes[] = {4096, 8192, 16384, 32768, 65536};
34 INSTANTIATE_TEST_SUITE_P(PageSize, SharedMemoryABITest, ValuesIn(kPageSizes));
35 
TEST_P(SharedMemoryABITest,NominalCases)36 TEST_P(SharedMemoryABITest, NominalCases) {
37   SharedMemoryABI abi(buf(), buf_size(), page_size());
38 
39   ASSERT_EQ(buf(), abi.start());
40   ASSERT_EQ(buf() + buf_size(), abi.end());
41   ASSERT_EQ(buf_size(), abi.size());
42   ASSERT_EQ(page_size(), abi.page_size());
43   ASSERT_EQ(kNumPages, abi.num_pages());
44 
45   for (size_t i = 0; i < kNumPages; i++) {
46     ASSERT_TRUE(abi.is_page_free(i));
47     ASSERT_FALSE(abi.is_page_complete(i));
48     // GetFreeChunks() should return 0 for an unpartitioned page.
49     ASSERT_EQ(0u, abi.GetFreeChunks(i));
50   }
51 
52   ASSERT_TRUE(abi.TryPartitionPage(0, SharedMemoryABI::kPageDiv1));
53   ASSERT_EQ(0x01u, abi.GetFreeChunks(0));
54 
55   ASSERT_TRUE(abi.TryPartitionPage(1, SharedMemoryABI::kPageDiv2));
56   ASSERT_EQ(0x03u, abi.GetFreeChunks(1));
57 
58   ASSERT_TRUE(abi.TryPartitionPage(2, SharedMemoryABI::kPageDiv4));
59   ASSERT_EQ(0x0fu, abi.GetFreeChunks(2));
60 
61   ASSERT_TRUE(abi.TryPartitionPage(3, SharedMemoryABI::kPageDiv7));
62   ASSERT_EQ(0x7fu, abi.GetFreeChunks(3));
63 
64   ASSERT_TRUE(abi.TryPartitionPage(4, SharedMemoryABI::kPageDiv14));
65   ASSERT_EQ(0x3fffu, abi.GetFreeChunks(4));
66 
67   // Repartitioning an existing page must fail.
68   ASSERT_FALSE(abi.TryPartitionPage(0, SharedMemoryABI::kPageDiv1));
69   ASSERT_FALSE(abi.TryPartitionPage(4, SharedMemoryABI::kPageDiv14));
70 
71   for (size_t i = 0; i <= 4; i++) {
72     ASSERT_FALSE(abi.is_page_free(i));
73     ASSERT_FALSE(abi.is_page_complete(i));
74   }
75 
76   uint16_t last_chunk_id = 0;
77   uint16_t last_writer_id = 0;
78   uint8_t* last_chunk_begin = nullptr;
79   uint8_t* last_chunk_end = nullptr;
80 
81   for (size_t page_idx = 0; page_idx <= 4; page_idx++) {
82     uint8_t* const page_start = buf() + page_idx * page_size();
83     uint8_t* const page_end = page_start + page_size();
84     const size_t num_chunks =
85         SharedMemoryABI::GetNumChunksForLayout(abi.GetPageLayout(page_idx));
86     Chunk chunks[14];
87 
88     for (size_t chunk_idx = 0; chunk_idx < num_chunks; chunk_idx++) {
89       Chunk& chunk = chunks[chunk_idx];
90       ChunkHeader header{};
91 
92       ASSERT_EQ(SharedMemoryABI::kChunkFree,
93                 abi.GetChunkState(page_idx, chunk_idx));
94       uint16_t chunk_id = ++last_chunk_id;
95       last_writer_id = (last_writer_id + 1) & kMaxWriterID;
96       uint16_t writer_id = last_writer_id;
97       header.chunk_id.store(chunk_id);
98       header.writer_id.store(writer_id);
99 
100       uint16_t packets_count = static_cast<uint16_t>(chunk_idx * 10);
101       const uint8_t kFlagsMask = (1 << 6) - 1;
102       uint8_t flags = static_cast<uint8_t>((0xffu - chunk_idx) & kFlagsMask);
103       header.packets.store({packets_count, flags});
104 
105       chunk = abi.TryAcquireChunkForWriting(page_idx, chunk_idx, &header);
106       ASSERT_TRUE(chunk.is_valid());
107       ASSERT_EQ(SharedMemoryABI::kChunkBeingWritten,
108                 abi.GetChunkState(page_idx, chunk_idx));
109 
110       // Sanity check chunk bounds.
111       size_t expected_chunk_size =
112           (page_size() - sizeof(SharedMemoryABI::PageHeader)) / num_chunks;
113       expected_chunk_size = expected_chunk_size - (expected_chunk_size % 4);
114       ASSERT_EQ(expected_chunk_size, chunk.size());
115       ASSERT_EQ(expected_chunk_size - sizeof(SharedMemoryABI::ChunkHeader),
116                 chunk.payload_size());
117       ASSERT_GT(chunk.begin(), page_start);
118       ASSERT_GT(chunk.begin(), last_chunk_begin);
119       ASSERT_GE(chunk.begin(), last_chunk_end);
120       ASSERT_LE(chunk.end(), page_end);
121       ASSERT_GT(chunk.end(), chunk.begin());
122       ASSERT_EQ(chunk.end(), chunk.begin() + chunk.size());
123       last_chunk_begin = chunk.begin();
124       last_chunk_end = chunk.end();
125 
126       ASSERT_EQ(chunk_id, chunk.header()->chunk_id.load());
127       ASSERT_EQ(writer_id, chunk.header()->writer_id.load());
128       ASSERT_EQ(packets_count, chunk.header()->packets.load().count);
129       ASSERT_EQ(flags, chunk.header()->packets.load().flags);
130       ASSERT_EQ(std::make_pair(packets_count, flags),
131                 chunk.GetPacketCountAndFlags());
132 
133       chunk.IncrementPacketCount();
134       ASSERT_EQ(packets_count + 1, chunk.header()->packets.load().count);
135 
136       chunk.IncrementPacketCount();
137       ASSERT_EQ(packets_count + 2, chunk.header()->packets.load().count);
138 
139       chunk.SetFlag(
140           SharedMemoryABI::ChunkHeader::kLastPacketContinuesOnNextChunk);
141       ASSERT_TRUE(
142           chunk.header()->packets.load().flags &
143           SharedMemoryABI::ChunkHeader::kLastPacketContinuesOnNextChunk);
144 
145       // Reacquiring the same chunk should fail.
146       ASSERT_FALSE(abi.TryAcquireChunkForWriting(page_idx, chunk_idx, &header)
147                        .is_valid());
148     }
149 
150     // Now release chunks and check the Release() logic.
151     for (size_t chunk_idx = 0; chunk_idx < num_chunks; chunk_idx++) {
152       Chunk& chunk = chunks[chunk_idx];
153 
154       size_t res = abi.ReleaseChunkAsComplete(std::move(chunk));
155       ASSERT_EQ(page_idx, res);
156       ASSERT_EQ(chunk_idx == num_chunks - 1, abi.is_page_complete(page_idx));
157       ASSERT_EQ(SharedMemoryABI::kChunkComplete,
158                 abi.GetChunkState(page_idx, chunk_idx));
159     }
160 
161     // Now acquire all chunks for reading.
162     for (size_t chunk_idx = 0; chunk_idx < num_chunks; chunk_idx++) {
163       Chunk& chunk = chunks[chunk_idx];
164       chunk = abi.TryAcquireChunkForReading(page_idx, chunk_idx);
165       ASSERT_TRUE(chunk.is_valid());
166       ASSERT_EQ(SharedMemoryABI::kChunkBeingRead,
167                 abi.GetChunkState(page_idx, chunk_idx));
168     }
169 
170     // Finally release all chunks as free.
171     for (size_t chunk_idx = 0; chunk_idx < num_chunks; chunk_idx++) {
172       Chunk& chunk = chunks[chunk_idx];
173 
174       // If this was the last chunk in the page, the full page should be marked
175       // as free.
176       size_t res = abi.ReleaseChunkAsFree(std::move(chunk));
177       ASSERT_EQ(page_idx, res);
178       ASSERT_EQ(chunk_idx == num_chunks - 1, abi.is_page_free(page_idx));
179       ASSERT_EQ(SharedMemoryABI::kChunkFree,
180                 abi.GetChunkState(page_idx, chunk_idx));
181     }
182   }
183 }
184 
185 }  // namespace
186 }  // namespace perfetto
187