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
content / common / profiling_utils.cc [blame]
// Copyright 2019 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "content/public/common/profiling_utils.h"
#include <limits>
#include <memory>
#include <string>
#include "base/base_paths.h"
#include "base/command_line.h"
#include "base/environment.h"
#include "base/files/file.h"
#include "base/files/file_path.h"
#include "base/files/file_util.h"
#include "base/logging.h"
#include "base/path_service.h"
#include "base/rand_util.h"
#include "base/strings/strcat.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/utf_string_conversions.h"
#include "base/threading/thread_restrictions.h"
#include "build/build_config.h"
#include "content/public/common/content_switches.h"
namespace content {
namespace {
// Returns the path where the PGO profiles should be saved.
// On Android this is always a static path, on other platforms it's either
// the path specified by the LLVM_PROFILE_FILE environment variable or the
// current path if it's not set.
base::FilePath GetProfileFileDirectory() {
base::FilePath path;
// Android differs from the other platforms because it's not possible to
// write in base::DIR_CURRENT and environment variables aren't well supported.
#if BUILDFLAG(IS_ANDROID)
base::PathService::Get(base::DIR_TEMP, &path);
path = path.Append("pgo_profiles/");
// Lacros is similar to Android that it's running on a device that is not
// the host machine and environment variables aren't well supported.
// But Lacros also need to pass in the path so it is the same path as
// isolate test output folder on bots.
#elif BUILDFLAG(IS_CHROMEOS_LACROS)
path = base::CommandLine::ForCurrentProcess()
->GetSwitchValuePath(switches::kLLVMProfileFile)
.DirName();
#else
std::string prof_template;
std::unique_ptr<base::Environment> env(base::Environment::Create());
if (env->GetVar("LLVM_PROFILE_FILE", &prof_template)) {
#if BUILDFLAG(IS_WIN)
path = base::FilePath(base::UTF8ToWide(prof_template)).DirName();
#else
path = base::FilePath(prof_template).DirName();
#endif
}
#endif
if (!path.empty()) {
base::CreateDirectory(path);
} else {
base::PathService::Get(base::DIR_CURRENT, &path);
}
return path;
}
} // namespace
base::File OpenProfilingFile() {
base::ScopedAllowBlockingForTesting allows_blocking;
base::FilePath path = GetProfileFileDirectory();
// sajjadm@ and liaoyuke@ experimentally determined that a size 4 pool works
// well for the coverage builder.
// TODO(crbug.com/40121559): Check if this is an appropriate value for
// the PGO builds.
int pool_index = base::RandInt(0, 3);
std::string filename = base::StrCat(
{"child_pool-", base::NumberToString(pool_index), ".profraw"});
#if BUILDFLAG(IS_WIN)
path = path.Append(base::UTF8ToWide(filename));
#else
path = path.Append(filename);
#endif
uint32_t flags = base::File::FLAG_OPEN_ALWAYS | base::File::FLAG_READ |
base::File::FLAG_WRITE;
// The profiling file is passed to an untrusted process.
flags = base::File::AddFlagsForPassingToUntrustedProcess(flags);
base::File file(path, flags);
if (!file.IsValid()) {
LOG(ERROR) << "Opening file: " << path << " failed with "
<< file.error_details();
}
return file;
}
} // namespace content