blob: 8dd28ff196889cfa0f70adad6eb0681659790fb6 [file] [log] [blame]
/*
* Copyright (C) 2019 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "CPU.h"
#if (CPU(X86) || CPU(X86_64)) && OS(DARWIN)
#include <mutex>
#include <sys/sysctl.h>
#endif
namespace JSC {
#if (CPU(X86) || CPU(X86_64)) && OS(DARWIN)
bool isKernTCSMAvailable()
{
uint32_t val = 0;
size_t valSize = sizeof(val);
int rc = sysctlbyname("kern.tcsm_available", &val, &valSize, NULL, 0);
if (rc < 0)
return false;
return !!val;
}
bool enableKernTCSM()
{
uint32_t val = 1;
int rc = sysctlbyname("kern.tcsm_enable", NULL, 0, &val, sizeof(val));
if (rc < 0)
return false;
return true;
}
int kernTCSMAwareNumberOfProcessorCores()
{
static std::once_flag onceFlag;
static int result;
std::call_once(onceFlag, [] {
result = WTF::numberOfProcessorCores();
if (result <= 1)
return;
if (isKernTCSMAvailable())
--result;
});
return result;
}
#endif // #if (CPU(X86) || CPU(X86_64)) && OS(DARWIN)
} // namespace JSC