/*
* Copyright 2016 higherfrequencytrading.com
*
* 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.
*
*/
package net.openhft.affinity.impl;
import com.sun.jna.*;
import com.sun.jna.ptr.IntByReference;
import com.sun.jna.ptr.PointerByReference;
import net.openhft.affinity.IAffinity;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.nio.ByteBuffer;
import java.util.Arrays;
import java.util.BitSet;
/**
* Implementation of {@link IAffinity} based on JNA call of
* sched_setaffinity(3)/sched_getaffinity(3) from 'c' library. Applicable for most
* linux/unix platforms
* <p>
* TODO Support assignment to core 64 and above
*
* @author peter.lawrey
* @author BegemoT
*/
public enum PosixJNAAffinity implements IAffinity {
INSTANCE;
public static final boolean LOADED;
private static final Logger LOGGER = LoggerFactory.getLogger(PosixJNAAffinity.class);
private static final String LIBRARY_NAME = Platform.isWindows() ? "msvcrt" : "c";
private static final int PROCESS_ID;
private static final boolean ISLINUX = "Linux".equals(System.getProperty("os.name"));
private static final boolean IS64BIT = is64Bit0();
private static final int SYS_gettid = is64Bit() ? 186 : 224;
private static final Object[] NO_ARGS = {};
static {
int processId;
try {
processId = CLibrary.INSTANCE.getpid();
} catch (Exception ignored) {
processId = -1;
}
PROCESS_ID = processId;
}
static {
boolean loaded = false;
try {
INSTANCE.getAffinity();
loaded = true;
} catch (UnsatisfiedLinkError e) {
LOGGER.warn("Unable to load jna library {}", e);
}
LOADED = loaded;
}
private final ThreadLocal<Integer> THREAD_ID = new ThreadLocal<Integer>();
public static boolean is64Bit() {
return IS64BIT;
}
private static boolean is64Bit0() {
String systemProp;
systemProp = System.getProperty("com.ibm.vm.bitmode");
if (systemProp != null) {
return "64".equals(systemProp);
}
systemProp = System.getProperty("sun.arch.data.model");
if (systemProp != null) {
return "64".equals(systemProp);
}
systemProp = System.getProperty("java.vm.version");
return systemProp != null && systemProp.contains("_64");
}
@Override
public BitSet getAffinity() {
final CLibrary lib = CLibrary.INSTANCE;
final int procs = Runtime.getRuntime().availableProcessors();
final int cpuSetSizeInLongs = (procs + 63) / 64;
final int cpuSetSizeInBytes = cpuSetSizeInLongs * 8;
final Memory cpusetArray = new Memory(cpuSetSizeInBytes);
final PointerByReference cpuset = new PointerByReference(cpusetArray);
try {
final int ret = lib.sched_getaffinity(0, cpuSetSizeInBytes, cpuset);
if (ret < 0) {
throw new IllegalStateException("sched_getaffinity((" + cpuSetSizeInBytes + ") , &(" + cpusetArray + ") ) return " + ret);
}
ByteBuffer buff = cpusetArray.getByteBuffer(0, cpuSetSizeInBytes);
return BitSet.valueOf(buff.array());
} catch (LastErrorException e) {
if (e.getErrorCode() != 22) {
throw new IllegalStateException("sched_getaffinity((" + cpuSetSizeInBytes + ") , &(" + cpusetArray + ") ) errorNo=" + e.getErrorCode(), e);
}
}
// fall back to the old method
final IntByReference cpuset32 = new IntByReference(0);
try {
final int ret = lib.sched_getaffinity(0, Integer.SIZE / 8, cpuset32);
if (ret < 0) {
throw new IllegalStateException("sched_getaffinity((" + Integer.SIZE / 8 + ") , &(" + cpuset32 + ") ) return " + ret);
}
long[] longs = new long[1];
longs[0] = cpuset32.getValue() & 0xFFFFFFFFL;
return BitSet.valueOf(longs);
} catch (LastErrorException e) {
throw new IllegalStateException("sched_getaffinity((" + Integer.SIZE / 8 + ") , &(" + cpuset32 + ") ) errorNo=" + e.getErrorCode(), e);
}
}
@Override
public void setAffinity(final BitSet affinity) {
int procs = Runtime.getRuntime().availableProcessors();
if (affinity.isEmpty()) {
throw new IllegalArgumentException("Cannot set zero affinity");
}
final CLibrary lib = CLibrary.INSTANCE;
byte[] buff = affinity.toByteArray();
final int cpuSetSizeInBytes = buff.length;
final Memory cpusetArray = new Memory(cpuSetSizeInBytes);
try {
cpusetArray.write(0, buff, 0, buff.length);
final int ret = lib.sched_setaffinity(0, cpuSetSizeInBytes, new PointerByReference(cpusetArray));
if (ret < 0) {
throw new IllegalStateException("sched_setaffinity((" + cpuSetSizeInBytes + ") , &(" + affinity + ") ) return " + ret);
}
} catch (LastErrorException e) {
if (e.getErrorCode() != 22 || !Arrays.equals(buff, cpusetArray.getByteArray(0, cpuSetSizeInBytes))) {
throw new IllegalStateException("sched_setaffinity((" + cpuSetSizeInBytes + ") , &(" + affinity + ") ) errorNo=" + e.getErrorCode(), e);
}
}
final int value = (int) affinity.toLongArray()[0];
if (value == 0) {
throw new IllegalArgumentException("Cannot set zero affinity");
}
final IntByReference cpuset32 = new IntByReference(0);
cpuset32.setValue(value);
try {
final int ret = lib.sched_setaffinity(0, Integer.SIZE / 8, cpuset32);
if (ret < 0)
throw new IllegalStateException("sched_setaffinity((" + Integer.SIZE / 8 + ") , &(" + Integer.toHexString(cpuset32.getValue()) + ") ) return " + ret);
} catch (LastErrorException e) {
throw new IllegalStateException("sched_setaffinity((" + Integer.SIZE / 8 + ") , &(" + Integer.toHexString(cpuset32.getValue()) + ") ) errorNo=" + e.getErrorCode(), e);
}
}
@Override
public int getCpu() {
final CLibrary lib = CLibrary.INSTANCE;
try {
final int ret = lib.sched_getcpu();
if (ret < 0)
throw new IllegalStateException("sched_getcpu( ) return " + ret);
return ret;
} catch (LastErrorException e) {
throw new IllegalStateException("sched_getcpu( ) errorNo=" + e.getErrorCode(), e);
} catch (UnsatisfiedLinkError ule) {
try {
final IntByReference cpu = new IntByReference();
final IntByReference node = new IntByReference();
final int ret = lib.syscall(318, cpu, node, null);
if (ret != 0) {
throw new IllegalStateException("getcpu( ) return " + ret);
}
return cpu.getValue();
} catch (LastErrorException lee) {
throw new IllegalStateException("getcpu( ) errorNo=" + lee.getErrorCode(), lee);
}
}
}
@Override
public int getProcessId() {
return PROCESS_ID;
}
@Override
public int getThreadId() {
if (ISLINUX) {
Integer tid = THREAD_ID.get();
if (tid == null)
THREAD_ID.set(tid = CLibrary.INSTANCE.syscall(SYS_gettid, NO_ARGS));
return tid;
}
return -1;
}
/**
* @author BegemoT
*/
interface CLibrary extends Library {
CLibrary INSTANCE = (CLibrary)
Native.loadLibrary(LIBRARY_NAME, CLibrary.class);
int sched_setaffinity(final int pid,
final int cpusetsize,
final PointerType cpuset) throws LastErrorException;
int sched_getaffinity(final int pid,
final int cpusetsize,
final PointerType cpuset) throws LastErrorException;
int sched_getcpu() throws LastErrorException;
int getcpu(final IntByReference cpu,
final IntByReference node,
final PointerType tcache) throws LastErrorException;
int getpid() throws LastErrorException;
int syscall(int number, Object... args) throws LastErrorException;
}
}