1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
|
// Copyright 2020 The gVisor Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include "gtest/gtest.h"
#include "benchmark/benchmark.h"
#include "test/util/file_descriptor.h"
#include "test/util/fs_util.h"
#include "test/util/temp_path.h"
#include "test/util/test_util.h"
#ifndef SYS_getdents64
#if defined(__x86_64__)
#define SYS_getdents64 217
#elif defined(__aarch64__)
#define SYS_getdents64 217
#else
#error "Unknown architecture"
#endif
#endif // SYS_getdents64
namespace gvisor {
namespace testing {
namespace {
constexpr int kBufferSize = 65536;
PosixErrorOr<TempPath> CreateDirectory(int count,
std::vector<std::string>* files) {
ASSIGN_OR_RETURN_ERRNO(TempPath dir, TempPath::CreateDir());
ASSIGN_OR_RETURN_ERRNO(FileDescriptor dfd,
Open(dir.path(), O_RDONLY | O_DIRECTORY));
for (int i = 0; i < count; i++) {
auto file = NewTempRelPath();
auto res = MknodAt(dfd, file, S_IFREG | 0644, 0);
RETURN_IF_ERRNO(res);
files->push_back(file);
}
return std::move(dir);
}
PosixError CleanupDirectory(const TempPath& dir,
std::vector<std::string>* files) {
ASSIGN_OR_RETURN_ERRNO(FileDescriptor dfd,
Open(dir.path(), O_RDONLY | O_DIRECTORY));
for (auto it = files->begin(); it != files->end(); ++it) {
auto res = UnlinkAt(dfd, *it, 0);
RETURN_IF_ERRNO(res);
}
return NoError();
}
// Creates a directory containing `files` files, and reads all the directory
// entries from the directory using a single FD.
void BM_GetdentsSameFD(benchmark::State& state) {
// Create directory with given files.
const int count = state.range(0);
// Keep a vector of all of the file TempPaths that is destroyed before dir.
//
// Normally, we'd simply allow dir to recursively clean up the contained
// files, but that recursive cleanup uses getdents, which may be very slow in
// extreme benchmarks.
TempPath dir;
std::vector<std::string> files;
dir = ASSERT_NO_ERRNO_AND_VALUE(CreateDirectory(count, &files));
FileDescriptor fd =
ASSERT_NO_ERRNO_AND_VALUE(Open(dir.path(), O_RDONLY | O_DIRECTORY));
char buffer[kBufferSize];
// We read all directory entries on each iteration, but report this as a
// "batch" iteration so that reported times are per file.
while (state.KeepRunningBatch(count)) {
ASSERT_THAT(lseek(fd.get(), 0, SEEK_SET), SyscallSucceeds());
int ret;
do {
ASSERT_THAT(ret = syscall(SYS_getdents64, fd.get(), buffer, kBufferSize),
SyscallSucceeds());
} while (ret > 0);
}
ASSERT_NO_ERRNO(CleanupDirectory(dir, &files));
state.SetItemsProcessed(state.iterations());
}
BENCHMARK(BM_GetdentsSameFD)->Range(1, 1 << 12)->UseRealTime();
// Creates a directory containing `files` files, and reads all the directory
// entries from the directory using a new FD each time.
void BM_GetdentsNewFD(benchmark::State& state) {
// Create directory with given files.
const int count = state.range(0);
// Keep a vector of all of the file TempPaths that is destroyed before dir.
//
// Normally, we'd simply allow dir to recursively clean up the contained
// files, but that recursive cleanup uses getdents, which may be very slow in
// extreme benchmarks.
TempPath dir;
std::vector<std::string> files;
dir = ASSERT_NO_ERRNO_AND_VALUE(CreateDirectory(count, &files));
char buffer[kBufferSize];
// We read all directory entries on each iteration, but report this as a
// "batch" iteration so that reported times are per file.
while (state.KeepRunningBatch(count)) {
FileDescriptor fd =
ASSERT_NO_ERRNO_AND_VALUE(Open(dir.path(), O_RDONLY | O_DIRECTORY));
int ret;
do {
ASSERT_THAT(ret = syscall(SYS_getdents64, fd.get(), buffer, kBufferSize),
SyscallSucceeds());
} while (ret > 0);
}
ASSERT_NO_ERRNO(CleanupDirectory(dir, &files));
state.SetItemsProcessed(state.iterations());
}
BENCHMARK(BM_GetdentsNewFD)->Range(1, 1 << 12)->UseRealTime();
} // namespace
} // namespace testing
} // namespace gvisor
|
