blob: 082d2d69761e656ecf33704b76df5f4670e46bb8 [file] [log] [blame]
// Copyright 2018 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "util/sys_info.h"
#include "base/logging.h"
#include "util/build_config.h"
#if defined(OS_POSIX)
#include <sys/utsname.h>
#include <unistd.h>
#endif
#if defined(OS_WIN)
#include <windows.h>
#endif
std::string OperatingSystemArchitecture() {
#if defined(OS_POSIX)
struct utsname info;
if (uname(&info) < 0) {
NOTREACHED();
return std::string();
}
std::string arch(info.machine);
if (arch == "i386" || arch == "i486" || arch == "i586" || arch == "i686") {
arch = "x86";
} else if (arch == "i86pc") {
// Solaris and illumos systems report 'i86pc' (an Intel x86 PC) as their
// machine for both 32-bit and 64-bit x86 systems. Considering the rarity
// of 32-bit systems at this point, it is safe to assume 64-bit.
arch = "x86_64";
} else if (arch == "amd64") {
arch = "x86_64";
} else if (std::string(info.sysname) == "AIX") {
arch = "ppc64";
}
return arch;
#elif defined(OS_WIN)
SYSTEM_INFO system_info = {};
::GetNativeSystemInfo(&system_info);
switch (system_info.wProcessorArchitecture) {
case PROCESSOR_ARCHITECTURE_INTEL:
return "x86";
case PROCESSOR_ARCHITECTURE_AMD64:
return "x86_64";
case PROCESSOR_ARCHITECTURE_IA64:
return "ia64";
}
return std::string();
#else
#error
#endif
}
int NumberOfProcessors() {
#if defined(OS_POSIX)
// sysconf returns the number of "logical" (not "physical") processors on both
// Mac and Linux. So we get the number of max available "logical" processors.
//
// Note that the number of "currently online" processors may be fewer than the
// returned value of NumberOfProcessors(). On some platforms, the kernel may
// make some processors offline intermittently, to save power when system
// loading is low.
//
// One common use case that needs to know the processor count is to create
// optimal number of threads for optimization. It should make plan according
// to the number of "max available" processors instead of "currently online"
// ones. The kernel should be smart enough to make all processors online when
// it has sufficient number of threads waiting to run.
long res = sysconf(_SC_NPROCESSORS_CONF);
if (res == -1) {
NOTREACHED();
return 1;
}
return static_cast<int>(res);
#elif defined(OS_WIN)
return ::GetActiveProcessorCount(ALL_PROCESSOR_GROUPS);
#else
#error
#endif
}