1 // Copyright 2014 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "chrome/browser/extensions/api/system_cpu/cpu_info_provider.h"
6
7 #include <windows.h>
8 #include <winternl.h>
9
10 #include "base/sys_info.h"
11
12 namespace extensions {
13
14 namespace {
15
16 const wchar_t kNtdll[] = L"ntdll.dll";
17 const char kNtQuerySystemInformationName[] = "NtQuerySystemInformation";
18
19 // See MSDN about NtQuerySystemInformation definition.
20 typedef DWORD (WINAPI *NtQuerySystemInformationPF)(DWORD system_info_class,
21 PVOID system_info,
22 ULONG system_info_length,
23 PULONG return_length);
24
25 } // namespace
26
QueryCpuTimePerProcessor(std::vector<linked_ptr<api::system_cpu::ProcessorInfo>> * infos)27 bool CpuInfoProvider::QueryCpuTimePerProcessor(
28 std::vector<linked_ptr<api::system_cpu::ProcessorInfo> >* infos) {
29 DCHECK(infos);
30
31 HMODULE ntdll = GetModuleHandle(kNtdll);
32 CHECK(ntdll != NULL);
33 NtQuerySystemInformationPF NtQuerySystemInformation =
34 reinterpret_cast<NtQuerySystemInformationPF>(
35 ::GetProcAddress(ntdll, kNtQuerySystemInformationName));
36
37 CHECK(NtQuerySystemInformation != NULL);
38
39 int num_of_processors = base::SysInfo::NumberOfProcessors();
40 scoped_ptr<SYSTEM_PROCESSOR_PERFORMANCE_INFORMATION[]> processor_info(
41 new SYSTEM_PROCESSOR_PERFORMANCE_INFORMATION[num_of_processors]);
42
43 ULONG returned_bytes = 0, bytes =
44 sizeof(SYSTEM_PROCESSOR_PERFORMANCE_INFORMATION) * num_of_processors;
45 if (!NT_SUCCESS(NtQuerySystemInformation(
46 SystemProcessorPerformanceInformation,
47 processor_info.get(), bytes, &returned_bytes)))
48 return false;
49
50 int returned_num_of_processors =
51 returned_bytes / sizeof(SYSTEM_PROCESSOR_PERFORMANCE_INFORMATION);
52
53 if (returned_num_of_processors != num_of_processors)
54 return false;
55
56 DCHECK_EQ(num_of_processors, static_cast<int>(infos->size()));
57 for (int i = 0; i < returned_num_of_processors; ++i) {
58 double kernel = static_cast<double>(processor_info[i].KernelTime.QuadPart),
59 user = static_cast<double>(processor_info[i].UserTime.QuadPart),
60 idle = static_cast<double>(processor_info[i].IdleTime.QuadPart);
61
62 // KernelTime needs to be fixed-up, because it includes both idle time and
63 // real kernel time.
64 infos->at(i)->usage.kernel = kernel - idle;
65 infos->at(i)->usage.user = user;
66 infos->at(i)->usage.idle = idle;
67 infos->at(i)->usage.total = kernel + user;
68 }
69
70 return true;
71 }
72
73 } // namespace extensions
74