Big refactoring step.

- Moves a lot of stuff from vibe.core.core to vibe.core.task
- Introduces TaskScheduler to unify the scheduling process
- Refines how tasks are scheduled and processed (can push to the front of the task queue and uses a marker task to keep track of the spot up to which to process)
- Start to add proper support for task interrupts and timeouts by properly cancelling in-flight async operations
- Work on ManualEvent - still not functional for the shared case
- Implement proper IP address parsing in NetworkAddress
This commit is contained in:
Sönke Ludwig 2016-06-14 08:01:03 +02:00
parent c3857d1bc9
commit 3b0e4e0452
6 changed files with 1097 additions and 678 deletions

File diff suppressed because it is too large Load diff

View file

@ -859,6 +859,7 @@ private struct LogOutputRange {
void put(dchar ch)
{
static import std.utf;
if (ch < 128) put(cast(char)ch);
else {
char[4] buf;

View file

@ -14,7 +14,8 @@ import std.functional : toDelegate;
import std.socket : AddressFamily, UnknownAddress;
import vibe.core.log;
import vibe.internal.async;
import core.time : Duration;
/**
Resolves the given host name/IP address string.
@ -29,13 +30,26 @@ NetworkAddress resolveHost(string host, AddressFamily address_family = AddressFa
/// ditto
NetworkAddress resolveHost(string host, ushort address_family, bool use_dns = true)
{
NetworkAddress ret;
ret.family = address_family;
if (host == "127.0.0.1") {
ret.family = AddressFamily.INET;
ret.sockAddrInet4.sin_addr.s_addr = 0x0100007F;
} else assert(false);
return ret;
import std.socket : parseAddress;
version (Windows) import std.c.windows.winsock : sockaddr_in, sockaddr_in6;
else import core.sys.posix.netinet.in_ : sockaddr_in, sockaddr_in6;
enforce(host.length > 0, "Host name must not be empty.");
if (host[0] == ':' || host[0] >= '0' && host[0] <= '9') {
auto addr = parseAddress(host);
enforce(address_family == AddressFamily.UNSPEC || addr.addressFamily == address_family);
NetworkAddress ret;
ret.family = addr.addressFamily;
switch (addr.addressFamily) with(AddressFamily) {
default: throw new Exception("Unsupported address family");
case INET: *ret.sockAddrInet4 = *cast(sockaddr_in*)addr.name; break;
case INET6: *ret.sockAddrInet6 = *cast(sockaddr_in6*)addr.name; break;
}
return ret;
} else {
enforce(use_dns, "Malformed IP address string.");
assert(false, "DNS lookup not implemented."); // TODO
}
}
@ -103,7 +117,11 @@ TCPConnection connectTCP(NetworkAddress addr)
scope uaddr = new UnknownAddress;
addr.toUnknownAddress(uaddr);
auto result = eventDriver.asyncAwait!"connectStream"(uaddr);
// FIXME: make this interruptible
auto result = asyncAwaitUninterruptible!(ConnectCallback,
cb => eventDriver.connectStream(uaddr, cb)
//cb => eventDriver.cancelConnect(cb)
);
enforce(result[1] == ConnectStatus.connected, "Failed to connect to "~addr.toString()~": "~result[1].to!string);
return TCPConnection(result[0]);
}
@ -354,7 +372,10 @@ mixin(tracer);
// TODO: timeout!!
if (m_context.readBuffer.length > 0) return true;
auto mode = timeout <= 0.seconds ? IOMode.immediate : IOMode.once;
auto res = eventDriver.asyncAwait!"readSocket"(m_socket, m_context.readBuffer.peekDst(), mode);
auto res = asyncAwait!(IOCallback,
cb => eventDriver.readSocket(m_socket, m_context.readBuffer.peekDst(), mode, cb),
cb => eventDriver.cancelRead(m_socket)
);
logTrace("Socket %s, read %s bytes: %s", res[0], res[2], res[1]);
assert(m_context.readBuffer.length == 0);
@ -403,7 +424,9 @@ mixin(tracer);
mixin(tracer);
if (bytes.length == 0) return;
auto res = eventDriver.asyncAwait!"writeSocket"(m_socket, bytes, IOMode.all);
auto res = asyncAwait!(IOCallback,
cb => eventDriver.writeSocket(m_socket, bytes, IOMode.all, cb),
cb => eventDriver.cancelWrite(m_socket));
switch (res[1]) {
default:

View file

@ -126,7 +126,7 @@ class LocalTaskSemaphore
//import vibe.utils.memory;
private {
struct Waiter {
static struct Waiter {
ManualEvent signal;
ubyte priority;
uint seq;
@ -632,28 +632,126 @@ ManualEvent createManualEvent()
{
return ManualEvent.init;
}
/// ditto
shared(ManualEvent) createSharedManualEvent()
{
return shared(ManualEvent).init;
}
/** A manually triggered cross-task event.
Note: the ownership can be shared between multiple fibers and threads.
*/
struct ManualEvent {
import core.thread : Thread;
import vibe.internal.async : asyncAwait, asyncAwaitUninterruptible;
private {
static struct Waiter {
Waiter* next;
immutable EventID event;
immutable EventDriver driver;
immutable Thread thread;
StackSList!ThreadWaiter tasks;
}
static struct ThreadWaiter {
ThreadWaiter* next;
Task task;
void delegate() @safe nothrow notifier;
void wait(void delegate() @safe nothrow del) @safe nothrow { assert(notifier is null); notifier = del; }
void cancel() @safe nothrow { notifier = null; }
void wait(void delegate() @safe nothrow del)
shared @safe nothrow {
notifier = del;
if (!next) eventDriver.waitForEvent(ms_threadEvent, &onEvent);
}
private void onEvent(EventID event)
@safe nothrow {
assert(event == ms_threadEvent);
notifier();
}
}
int m_emitCount;
Waiter* m_waiters;
}
// thread destructor in vibe.core.core will decrement the ref. count
package static EventID ms_threadEvent;
enum EmitMode {
single,
all
}
//@disable this(this);
deprecated("ManualEvent is always non-null!")
bool opCast() const nothrow { return true; }
int emitCount() const nothrow { return 0; }
int emit() nothrow { return 0; }
int wait() { assert(false); }
int wait(int) { import vibe.core.core : sleep; sleep(30.seconds); assert(false); }
int wait(Duration, int) { assert(false); }
int waitUninterruptible() nothrow { assert(false); }
int waitUninterruptible(int) nothrow { assert(false); }
int waitUninterruptible(Duration, int) nothrow { assert(false); }
}
/+interface ManualEvent {
deprecated("ManualEvent is always non-null!")
bool opCast() const shared nothrow { return true; }
/// A counter that is increased with every emit() call
@property int emitCount() const nothrow;
int emitCount() const nothrow { return m_emitCount; }
/// ditto
int emitCount() const shared nothrow { return atomicLoad(m_emitCount); }
/// Emits the signal, waking up all owners of the signal.
void emit() nothrow;
int emit(EmitMode mode = EmitMode.all)
shared nothrow {
import core.atomic : atomicOp, cas;
auto ec = atomicOp!"+="(m_emitCount, 1);
auto thisthr = Thread.getThis();
final switch (mode) {
case EmitMode.all:
// FIXME: would be nice to have atomicSwap instead
auto w = cast(Waiter*)atomicLoad(m_waiters);
if (w !is null && !cas(&m_waiters, cast(shared(Waiter)*)w, cast(shared(Waiter)*)null))
return ec;
while (w !is null) {
if (w.thread is thisthr) {
// Note: emitForThisThread can result in w getting deallocated at any
// time, so we need to copy any fields first
auto tasks = w.tasks;
w = w.next;
emitForThisThread(w.tasks.m_first, mode);
} else {
auto evt = w.event;
w = w.next;
eventDriver.triggerEvent(evt, true);
}
}
break;
case EmitMode.single:
assert(false);
}
return ec;
}
/// ditto
int emit(EmitMode mode = EmitMode.all)
nothrow {
auto ec = m_emitCount++;
final switch (mode) {
case EmitMode.all:
auto w = m_waiters;
m_waiters = null;
if (w !is null) {
assert(w.thread is Thread.getThis(), "Unshared ManualEvent has waiters in foreign thread!");
assert(w.next is null, "Unshared ManualEvent has waiters in multiple threads!");
emitForThisThread(w.tasks.m_first, EmitMode.all);
}
break;
case EmitMode.single:
assert(false);
}
return ec;
}
/** Acquires ownership and waits until the signal is emitted.
@ -661,7 +759,9 @@ struct ManualEvent {
May throw an $(D InterruptException) if the task gets interrupted
using $(D Task.interrupt()).
*/
void wait();
int wait() { return wait(this.emitCount); }
/// ditto
int wait() shared { return wait(this.emitCount); }
/** Acquires ownership and waits until the emit count differs from the given one.
@ -669,7 +769,9 @@ struct ManualEvent {
May throw an $(D InterruptException) if the task gets interrupted
using $(D Task.interrupt()).
*/
int wait(int reference_emit_count);
int wait(int emit_count) { return wait(Duration.max, emit_count); }
/// ditto
int wait(int emit_count) shared { return wait(Duration.max, emit_count); }
/** Acquires ownership and waits until the emit count differs from the given one or until a timeout is reaced.
@ -677,32 +779,218 @@ struct ManualEvent {
May throw an $(D InterruptException) if the task gets interrupted
using $(D Task.interrupt()).
*/
int wait(Duration timeout, int reference_emit_count);
int wait(Duration timeout, int emit_count)
{
Waiter w;
ThreadWaiter tw;
int ec = this.emitCount;
while (ec <= emit_count) {
// wait for getting resumed directly by emit/emitForThisThread
acquireWaiter(w, tw);
asyncAwait!(void delegate() @safe nothrow,
cb => tw.wait(cb),
cb => tw.cancel()
)(timeout);
ec = this.emitCount;
}
return ec;
}
/// ditto
int wait(Duration timeout, int emit_count)
shared {
shared(Waiter) w;
ThreadWaiter tw;
acquireWaiter(w, tw);
int ec = this.emitCount;
while (ec <= emit_count) {
if (tw.next) {
// if we are not the first waiter for this thread,
// wait for getting resumed by emitForThisThread
asyncAwait!(void delegate() @safe nothrow,
cb => tw.wait(cb),
cb => tw.cancel()
)(timeout);
ec = this.emitCount;
} else {
// if we are the first waiter for this thread,
// wait for the thread event to get emitted
/*asyncAwait!(EventCallback, void delegate() @safe nothrow,
cb => eventDriver.waitForEvent(ms_threadEvent, cb),
cb => tw.wait(cb),
cb => eventDriver.cancelWaitForEvent(ms_threadEvent)
)(timeout);
emitForThisThread(w.waiters);
ec = this.emitCount;*/
assert(false);
}
}
return ec;
}
/** Same as $(D wait), but defers throwing any $(D InterruptException).
This method is annotated $(D nothrow) at the expense that it cannot be
interrupted.
*/
int waitUninterruptible(int reference_emit_count) nothrow;
int waitUninterruptible() nothrow { return waitUninterruptible(this.emitCount); }
///
int waitUninterruptible() shared nothrow { return waitUninterruptible(this.emitCount); }
/// ditto
int waitUninterruptible(Duration timeout, int reference_emit_count) nothrow;
}+/
int waitUninterruptible(int emit_count) nothrow { return waitUninterruptible(Duration.max, emit_count); }
/// ditto
int waitUninterruptible(int emit_count) shared nothrow { return waitUninterruptible(Duration.max, emit_count); }
/// ditto
int waitUninterruptible(Duration timeout, int emit_count)
nothrow {
Waiter w;
ThreadWaiter tw;
acquireWaiter(w, tw);
int ec = this.emitCount;
while (ec <= emit_count) {
asyncAwaitUninterruptible!(void delegate(),
cb => tw.wait(cb),
cb => tw.cancel()
)(timeout);
ec = this.emitCount;
}
return ec;
}
/// ditto
int waitUninterruptible(Duration timeout, int emit_count)
shared nothrow {
/*Waiter w;
ThreadWaiter tw;
auto event = acquireWaiter(w, tw);
int ec = this.emitCount;
while (ec <= emit_count) {
asyncAwaitUninterruptible!(void delegate(),
cb => tw.wait(cb),
cb => tw.cancel()
)(timeout);
ec = this.emitCount;
}
return ec;*/
assert(false);
}
private static bool emitForThisThread(ThreadWaiter* waiters, EmitMode mode)
nothrow {
if (!waiters) return false;
final switch (mode) {
case EmitMode.all:
while (waiters) {
if (waiters.notifier !is null)
waiters.notifier();
waiters = waiters.next;
}
break;
case EmitMode.single:
assert(false, "TODO!");
}
return true;
}
private void acquireWaiter(ref Waiter w, ref ThreadWaiter tw)
nothrow {
// FIXME: this doesn't work! if task a starts to wait, task b afterwards, and then a finishes its wait before b, the Waiter will be dangling
tw.task = Task.getThis();
if (m_waiters) {
m_waiters.tasks.add(&tw);
} else {
m_waiters = &w;
}
}
private void acquireWaiter(ref shared(Waiter) w, ref ThreadWaiter tw)
nothrow shared {
tw.task = Task.getThis();
if (ms_threadEvent == EventID.init)
ms_threadEvent = eventDriver.createEvent();
if (m_waiters) {
//m_waiters.tasks.add(&tw);
assert(false);
} else {
m_waiters = &w;
}
}
}
private struct StackSList(T)
{
import core.atomic : cas;
private T* m_first;
@property T* first() { return m_first; }
@property shared(T)* first() shared { return atomicLoad(m_first); }
void add(shared(T)* elem)
shared {
do elem.next = atomicLoad(m_first);
while (cas(&m_first, elem.next, elem));
}
void remove(shared(T)* elem)
shared {
while (true) {
shared(T)* w = atomicLoad(m_first), wp;
while (w !is elem) {
wp = w;
w = atomicLoad(w.next);
}
if (wp !is null) {
if (cas(&wp.next, w, w.next))
break;
} else {
if (cas(&m_first, w, w.next))
break;
}
}
}
bool empty() const { return m_first is null; }
void add(T* elem)
{
elem.next = m_first;
m_first = elem;
}
void remove(T* elem)
{
T* w = m_first, wp;
while (w !is elem) {
assert(w !is null);
wp = w;
w = w.next;
}
if (wp) wp.next = w.next;
else m_first = w.next;
}
}
private struct TaskMutexImpl(bool INTERRUPTIBLE) {
import std.stdio;
private {
shared(bool) m_locked = false;
shared(uint) m_waiters = 0;
ManualEvent m_signal;
shared(ManualEvent) m_signal;
debug Task m_owner;
}
void setup()
{
m_signal = createManualEvent();
m_signal = createSharedManualEvent();
}
@ -751,13 +1039,13 @@ private struct RecursiveTaskMutexImpl(bool INTERRUPTIBLE) {
Task m_owner;
size_t m_recCount = 0;
shared(uint) m_waiters = 0;
ManualEvent m_signal;
shared(ManualEvent) m_signal;
@property bool m_locked() const { return m_recCount > 0; }
}
void setup()
{
m_signal = createManualEvent();
m_signal = createSharedManualEvent();
m_mutex = new core.sync.mutex.Mutex;
}
@ -812,7 +1100,7 @@ private struct TaskConditionImpl(bool INTERRUPTIBLE, LOCKABLE) {
private {
LOCKABLE m_mutex;
ManualEvent m_signal;
shared(ManualEvent) m_signal;
}
static if (is(LOCKABLE == Lockable)) {
@ -833,7 +1121,7 @@ private struct TaskConditionImpl(bool INTERRUPTIBLE, LOCKABLE) {
void setup(LOCKABLE mtx)
{
m_mutex = mtx;
m_signal = createManualEvent();
m_signal = createSharedManualEvent();
}
@property LOCKABLE mutex() { return m_mutex; }
@ -955,9 +1243,9 @@ private struct ReadWriteMutexState(bool INTERRUPTIBLE)
//Queue Events
/** The event used to wake reading tasks waiting for the lock while it is blocked. */
ManualEvent m_readyForReadLock;
shared(ManualEvent) m_readyForReadLock;
/** The event used to wake writing tasks waiting for the lock while it is blocked. */
ManualEvent m_readyForWriteLock;
shared(ManualEvent) m_readyForWriteLock;
/** The underlying mutex that gates the access to the shared state. */
Mutex m_counterMutex;
@ -967,8 +1255,8 @@ private struct ReadWriteMutexState(bool INTERRUPTIBLE)
{
m_policy = policy;
m_counterMutex = new Mutex();
m_readyForReadLock = createManualEvent();
m_readyForWriteLock = createManualEvent();
m_readyForReadLock = createSharedManualEvent();
m_readyForWriteLock = createSharedManualEvent();
}
@disable this(this);

View file

@ -7,8 +7,8 @@
*/
module vibe.core.task;
import vibe.core.log;
import vibe.core.sync;
import vibe.internal.array : FixedRingBuffer;
import core.thread;
import std.exception;
@ -58,29 +58,29 @@ struct Task {
}
nothrow {
@property inout(TaskFiber) fiber() inout @trusted { return cast(inout(TaskFiber))m_fiber; }
package @property inout(TaskFiber) taskFiber() inout @trusted { return cast(inout(TaskFiber))m_fiber; }
@property inout(Fiber) fiber() inout @trusted { return this.taskFiber; }
@property size_t taskCounter() const @safe { return m_taskCounter; }
@property inout(Thread) thread() inout @safe { if (m_fiber) return this.fiber.thread; return null; }
@property inout(Thread) thread() inout @safe { if (m_fiber) return this.taskFiber.thread; return null; }
/** Determines if the task is still running.
*/
@property bool running()
const @trusted {
assert(m_fiber !is null, "Invalid task handle");
try if (this.fiber.state == Fiber.State.TERM) return false; catch (Throwable) {}
return this.fiber.m_running && this.fiber.m_taskCounter == m_taskCounter;
try if (this.taskFiber.state == Fiber.State.TERM) return false; catch (Throwable) {}
return this.taskFiber.m_running && this.taskFiber.m_taskCounter == m_taskCounter;
}
// FIXME: this is not thread safe!
@property ref ThreadInfo tidInfo() { return m_fiber ? fiber.tidInfo : s_tidInfo; }
@property ref ThreadInfo tidInfo() { return m_fiber ? taskFiber.tidInfo : s_tidInfo; }
@property Tid tid() { return tidInfo.ident; }
}
T opCast(T)() const nothrow if (is(T == bool)) { return m_fiber !is null; }
void join() { if (running) fiber.join(); }
void interrupt() { if (running) fiber.interrupt(); }
void terminate() { if (running) fiber.terminate(); }
void join() { if (running) taskFiber.join(); }
void interrupt() { if (running) taskFiber.interrupt(); }
string toString() const { import std.string; return format("%s:%s", cast(void*)m_fiber, m_taskCounter); }
@ -88,6 +88,155 @@ struct Task {
bool opEquals(in Task other) const nothrow @safe { return m_fiber is other.m_fiber && m_taskCounter == other.m_taskCounter; }
}
/**
Implements a task local storage variable.
Task local variables, similar to thread local variables, exist separately
in each task. Consequently, they do not need any form of synchronization
when accessing them.
Note, however, that each TaskLocal variable will increase the memory footprint
of any task that uses task local storage. There is also an overhead to access
TaskLocal variables, higher than for thread local variables, but generelly
still O(1) (since actual storage acquisition is done lazily the first access
can require a memory allocation with unknown computational costs).
Notice:
FiberLocal instances MUST be declared as static/global thread-local
variables. Defining them as a temporary/stack variable will cause
crashes or data corruption!
Examples:
---
TaskLocal!string s_myString = "world";
void taskFunc()
{
assert(s_myString == "world");
s_myString = "hello";
assert(s_myString == "hello");
}
shared static this()
{
// both tasks will get independent storage for s_myString
runTask(&taskFunc);
runTask(&taskFunc);
}
---
*/
struct TaskLocal(T)
{
private {
size_t m_offset = size_t.max;
size_t m_id;
T m_initValue;
bool m_hasInitValue = false;
}
this(T init_val) { m_initValue = init_val; m_hasInitValue = true; }
@disable this(this);
void opAssign(T value) { this.storage = value; }
@property ref T storage()
{
auto fiber = TaskFiber.getThis();
// lazily register in FLS storage
if (m_offset == size_t.max) {
static assert(T.alignof <= 8, "Unsupported alignment for type "~T.stringof);
assert(TaskFiber.ms_flsFill % 8 == 0, "Misaligned fiber local storage pool.");
m_offset = TaskFiber.ms_flsFill;
m_id = TaskFiber.ms_flsCounter++;
TaskFiber.ms_flsFill += T.sizeof;
while (TaskFiber.ms_flsFill % 8 != 0)
TaskFiber.ms_flsFill++;
}
// make sure the current fiber has enough FLS storage
if (fiber.m_fls.length < TaskFiber.ms_flsFill) {
fiber.m_fls.length = TaskFiber.ms_flsFill + 128;
fiber.m_flsInit.length = TaskFiber.ms_flsCounter + 64;
}
// return (possibly default initialized) value
auto data = fiber.m_fls.ptr[m_offset .. m_offset+T.sizeof];
if (!fiber.m_flsInit[m_id]) {
fiber.m_flsInit[m_id] = true;
import std.traits : hasElaborateDestructor, hasAliasing;
static if (hasElaborateDestructor!T || hasAliasing!T) {
void function(void[], size_t) destructor = (void[] fls, size_t offset){
static if (hasElaborateDestructor!T) {
auto obj = cast(T*)&fls[offset];
// call the destructor on the object if a custom one is known declared
obj.destroy();
}
else static if (hasAliasing!T) {
// zero the memory to avoid false pointers
foreach (size_t i; offset .. offset + T.sizeof) {
ubyte* u = cast(ubyte*)&fls[i];
*u = 0;
}
}
};
FLSInfo fls_info;
fls_info.fct = destructor;
fls_info.offset = m_offset;
// make sure flsInfo has enough space
if (ms_flsInfo.length <= m_id)
ms_flsInfo.length = m_id + 64;
ms_flsInfo[m_id] = fls_info;
}
if (m_hasInitValue) {
static if (__traits(compiles, emplace!T(data, m_initValue)))
emplace!T(data, m_initValue);
else assert(false, "Cannot emplace initialization value for type "~T.stringof);
} else emplace!T(data);
}
return (cast(T[])data)[0];
}
alias storage this;
}
/** Exception that is thrown by Task.interrupt.
*/
class InterruptException : Exception {
this()
@safe nothrow {
super("Task interrupted.");
}
}
/**
High level state change events for a Task
*/
enum TaskEvent {
preStart, /// Just about to invoke the fiber which starts execution
postStart, /// After the fiber has returned for the first time (by yield or exit)
start, /// Just about to start execution
yield, /// Temporarily paused
resume, /// Resumed from a prior yield
end, /// Ended normally
fail /// Ended with an exception
}
alias TaskEventCallback = void function(TaskEvent, Task) nothrow;
/**
The maximum combined size of all parameters passed to a task delegate
See_Also: runTask
*/
enum maxTaskParameterSize = 128;
/** The base class for a task aka Fiber.
@ -95,24 +244,135 @@ struct Task {
This class represents a single task that is executed concurrently
with other tasks. Each task is owned by a single thread.
*/
class TaskFiber : Fiber {
private {
Thread m_thread;
import std.concurrency : ThreadInfo;
ThreadInfo m_tidInfo;
}
final package class TaskFiber : Fiber {
static if ((void*).sizeof >= 8) enum defaultTaskStackSize = 16*1024*1024;
else enum defaultTaskStackSize = 512*1024;
protected {
private {
import std.concurrency : ThreadInfo;
import std.bitmanip : BitArray;
// task queue management (TaskScheduler.m_taskQueue)
TaskFiber m_prev, m_next;
TaskFiberQueue* m_queue;
Thread m_thread;
ThreadInfo m_tidInfo;
shared size_t m_taskCounter;
shared bool m_running;
Task[] m_joiners;
// task local storage
BitArray m_flsInit;
void[] m_fls;
bool m_interrupt; // Task.interrupt() is progress
static TaskFiber ms_globalDummyFiber;
static FLSInfo[] ms_flsInfo;
static size_t ms_flsFill = 0; // thread-local
static size_t ms_flsCounter = 0;
}
protected this(void delegate() fun, size_t stack_size)
nothrow {
super(fun, stack_size);
package TaskFuncInfo m_taskFunc;
package __gshared size_t ms_taskStackSize = defaultTaskStackSize;
package __gshared debug TaskEventCallback ms_taskEventCallback;
this()
@trusted nothrow {
super(&run, ms_taskStackSize);
m_thread = Thread.getThis();
}
static TaskFiber getThis()
@safe nothrow {
auto f = () @trusted nothrow {
return Fiber.getThis();
} ();
if (f) return cast(TaskFiber)f;
if (!ms_globalDummyFiber) ms_globalDummyFiber = new TaskFiber;
return ms_globalDummyFiber;
}
@property State state()
@trusted const nothrow {
return super.state;
}
private void run()
{
import std.encoding : sanitize;
import std.concurrency : Tid;
import vibe.core.core : isEventLoopRunning, recycleFiber, taskScheduler, yield;
version (VibeDebugCatchAll) alias UncaughtException = Throwable;
else alias UncaughtException = Exception;
try {
while (true) {
while (!m_taskFunc.func) {
try {
Fiber.yield();
} catch (Exception e) {
logWarn("CoreTaskFiber was resumed with exception but without active task!");
logDiagnostic("Full error: %s", e.toString().sanitize());
}
}
auto task = m_taskFunc;
m_taskFunc = TaskFuncInfo.init;
Task handle = this.task;
try {
m_running = true;
scope(exit) m_running = false;
std.concurrency.thisTid; // force creation of a message box
debug if (ms_taskEventCallback) ms_taskEventCallback(TaskEvent.start, handle);
if (!isEventLoopRunning) {
logTrace("Event loop not running at task start - yielding.");
vibe.core.core.yield();
logTrace("Initial resume of task.");
}
task.func(&task);
debug if (ms_taskEventCallback) ms_taskEventCallback(TaskEvent.end, handle);
} catch (Exception e) {
debug if (ms_taskEventCallback) ms_taskEventCallback(TaskEvent.fail, handle);
import std.encoding;
logCritical("Task terminated with uncaught exception: %s", e.msg);
logDebug("Full error: %s", e.toString().sanitize());
}
this.tidInfo.ident = Tid.init; // clear message box
foreach (t; m_joiners) taskScheduler.switchTo(t);
m_joiners.length = 0;
m_joiners.assumeSafeAppend();
// make sure that the task does not get left behind in the yielder queue if terminated during yield()
if (m_queue) m_queue.remove(this);
// zero the fls initialization ByteArray for memory safety
foreach (size_t i, ref bool b; m_flsInit) {
if (b) {
if (ms_flsInfo !is null && ms_flsInfo.length >= i && ms_flsInfo[i] != FLSInfo.init)
ms_flsInfo[i].destroy(m_fls);
b = false;
}
}
// make the fiber available for the next task
recycleFiber(this);
}
} catch(UncaughtException th) {
logCritical("CoreTaskFiber was terminated unexpectedly: %s", th.msg);
logDiagnostic("Full error: %s", th.toString().sanitize());
}
}
/** Returns the thread that owns this task.
*/
@property inout(Thread) thread() inout @safe nothrow { return m_thread; }
@ -123,31 +383,289 @@ class TaskFiber : Fiber {
@property ref inout(ThreadInfo) tidInfo() inout nothrow { return m_tidInfo; }
@property size_t taskCounter() const { return m_taskCounter; }
/** Blocks until the task has ended.
*/
abstract void join();
void join()
{
import vibe.core.core : hibernate, yield;
/** Throws an InterruptExeption within the task as soon as it calls a blocking function.
*/
abstract void interrupt();
auto caller = Task.getThis();
if (!m_running) return;
if (caller != Task.init) {
assert(caller.fiber !is this, "A task cannot join itself.");
assert(caller.thread is this.thread, "Joining tasks in foreign threads is currently not supported.");
m_joiners ~= caller;
} else assert(Thread.getThis() is this.thread, "Joining tasks in different threads is not yet supported.");
auto run_count = m_taskCounter;
if (caller == Task.init) vibe.core.core.yield(); // let the task continue (it must be yielded currently)
while (m_running && run_count == m_taskCounter) hibernate();
}
/** Terminates the task without notice as soon as it calls a blocking function.
/** Throws an InterruptExeption within the task as soon as it calls an interruptible function.
*/
abstract void terminate();
void interrupt()
{
import vibe.core.core : taskScheduler;
auto caller = Task.getThis();
if (caller != Task.init) {
assert(caller != this.task, "A task cannot interrupt itself.");
assert(caller.thread is this.thread, "Interrupting tasks in different threads is not yet supported.");
} else assert(Thread.getThis() is this.thread, "Interrupting tasks in different threads is not yet supported.");
m_interrupt = true;
taskScheduler.switchTo(this.task);
}
void bumpTaskCounter()
@safe nothrow {
import core.atomic : atomicOp;
() @trusted { atomicOp!"+="(this.m_taskCounter, 1); } ();
}
}
/** Exception that is thrown by Task.interrupt.
*/
class InterruptException : Exception {
this()
{
super("Task interrupted.");
package void handleInterrupt(scope void delegate() @safe nothrow on_interrupt)
@safe nothrow {
assert(Task.getThis().fiber is this, "Handling interrupt outside of the corresponding fiber.");
if (m_interrupt && on_interrupt) {
m_interrupt = false;
on_interrupt();
}
}
}
package struct TaskFuncInfo {
void function(TaskFuncInfo*) func;
void[2*size_t.sizeof] callable = void;
void[maxTaskParameterSize] args = void;
@property ref C typedCallable(C)()
{
static assert(C.sizeof <= callable.sizeof);
return *cast(C*)callable.ptr;
}
@property ref A typedArgs(A)()
{
static assert(A.sizeof <= args.sizeof);
return *cast(A*)args.ptr;
}
void initCallable(C)()
{
C cinit;
this.callable[0 .. C.sizeof] = cast(void[])(&cinit)[0 .. 1];
}
void initArgs(A)()
{
A ainit;
this.args[0 .. A.sizeof] = cast(void[])(&ainit)[0 .. 1];
}
}
package struct TaskScheduler {
private {
TaskFiberQueue m_taskQueue;
TaskFiber m_markerTask;
}
@safe nothrow:
@disable this(this);
@property size_t scheduledTaskCount() const { return m_taskQueue.length; }
/** Lets other pending tasks execute before continuing execution.
This will give other tasks or events a chance to be processed. If
multiple tasks call this function, they will be processed in a
fírst-in-first-out manner.
*/
void yield()
{
auto t = Task.getThis();
if (t == Task.init) return; // not really a task -> no-op
if (t.taskFiber.m_queue !is null) return; // already scheduled to be resumed
m_taskQueue.insertBack(t.taskFiber);
doYield(t);
}
/** Holds execution until the task gets explicitly resumed.
*/
void hibernate()
{
import vibe.core.core : isEventLoopRunning;
auto thist = Task.getThis();
if (thist == Task.init) {
assert(!isEventLoopRunning, "Event processing outside of a fiber should only happen before the event loop is running!?");
static import vibe.core.core;
vibe.core.core.processEvents();
} else {
doYield(thist);
}
}
/** Immediately switches execution to the specified task without giving up execution privilege.
This forces immediate execution of the specified task. After the tasks finishes or yields,
the calling task will continue execution.
*/
void switchTo(Task t)
{
auto thist = Task.getThis();
auto thisthr = thist ? thist.taskFiber.thread : () @trusted { return Thread.getThis(); } ();
assert(t.thread is thisthr, "Cannot switch to a task that lives in a different thread.");
if (thist == Task.init) {
resumeTask(t);
} else {
assert(!thist.taskFiber.m_queue, "Task already scheduled to be resumed... FIXME: should this really be an error?");
m_taskQueue.insertFront(thist.taskFiber);
m_taskQueue.insertFront(t.taskFiber);
doYield(thist);
}
}
/** Runs any pending tasks.
A pending tasks is a task that is scheduled to be resumed by either `yield` or
`switchTo`.
Returns:
Returns `true` $(I iff) there are more tasks left to process.
*/
bool schedule()
{
if (!m_markerTask) m_markerTask = new TaskFiber; // TODO: avoid allocating an actual task here!
assert(Task.getThis() == Task.init, "TaskScheduler.schedule() may not be called from a task!");
assert(!m_markerTask.m_queue, "TaskScheduler.schedule() was called recursively!");
// keep track of the end of the queue, so that we don't process tasks
// infinitely
m_taskQueue.insertBack(m_markerTask);
while (m_taskQueue.front !is m_markerTask) {
auto t = m_taskQueue.front;
m_taskQueue.popFront();
resumeTask(t.task);
assert(!m_taskQueue.empty, "Marker task got removed from tasks queue!?");
if (m_taskQueue.empty) return false; // handle gracefully in release mode
}
// remove marker task
m_taskQueue.popFront();
return !m_taskQueue.empty;
}
/// Resumes execution of a yielded task.
private void resumeTask(Task t)
{
import std.encoding : sanitize;
auto uncaught_exception = () @trusted nothrow { return t.fiber.call!(Fiber.Rethrow.no)(); } ();
if (uncaught_exception) {
auto th = cast(Throwable)uncaught_exception;
assert(th, "Fiber returned exception object that is not a Throwable!?");
assert(() @trusted nothrow { return t.fiber.state; } () == Fiber.State.TERM);
logError("Task terminated with unhandled exception: %s", th.msg);
logDebug("Full error: %s", () @trusted { return th.toString().sanitize; } ());
// always pass Errors on
if (auto err = cast(Error)th) throw err;
}
}
private void doYield(Task task)
{
debug if (TaskFiber.ms_taskEventCallback) () @trusted { TaskFiber.ms_taskEventCallback(TaskEvent.yield, task); } ();
() @trusted { Fiber.yield(); } ();
debug if (TaskFiber.ms_taskEventCallback) () @trusted { TaskFiber.ms_taskEventCallback(TaskEvent.resume, task); } ();
}
}
private struct TaskFiberQueue {
@safe nothrow:
TaskFiber first, last;
size_t length;
@disable this(this);
@property bool empty() const { return first is null; }
@property TaskFiber front() { return first; }
void insertFront(TaskFiber task)
{
assert(task.m_queue == null, "Task is already scheduled to be resumed!");
assert(task.m_prev is null, "Task has m_prev set without being in a queue!?");
assert(task.m_next is null, "Task has m_next set without being in a queue!?");
task.m_queue = &this;
if (empty) {
first = task;
last = task;
} else {
first.m_prev = task;
task.m_next = first;
first = task;
}
length++;
}
void insertBack(TaskFiber task)
{
assert(task.m_queue == null, "Task is already scheduled to be resumed!");
assert(task.m_prev is null, "Task has m_prev set without being in a queue!?");
assert(task.m_next is null, "Task has m_next set without being in a queue!?");
task.m_queue = &this;
if (empty) {
first = task;
last = task;
} else {
last.m_next = task;
task.m_prev = last;
last = task;
}
length++;
}
void popFront()
{
if (first is last) last = null;
assert(first && first.m_queue == &this, "Popping from empty or mismatching queue");
auto next = first.m_next;
if (next) next.m_prev = null;
first.m_next = null;
first.m_queue = null;
first = next;
length--;
}
void remove(TaskFiber task)
{
assert(task.m_queue is &this, "Task is not contained in task queue.");
if (task.m_prev) task.m_prev.m_next = task.m_next;
else first = task.m_next;
if (task.m_next) task.m_next.m_prev = task.m_prev;
else last = task.m_prev;
task.m_queue = null;
task.m_prev = null;
task.m_next = null;
}
}
private struct FLSInfo {
void function(void[], size_t) fct;
size_t offset;
void destroy(void[] fls) {
fct(fls, offset);
}
}

View file

@ -2,15 +2,39 @@ module vibe.internal.async;
import std.traits : ParameterTypeTuple;
import std.typecons : tuple;
import vibe.core.core;
import vibe.core.core : hibernate, switchToTask;
import vibe.core.task : InterruptException, Task;
import vibe.core.log;
import core.time : Duration, seconds;
auto asyncAwait(string method, Object, ARGS...)(Object object, ARGS args)
auto asyncAwait(Callback, alias action, alias cancel, string func = __FUNCTION__)()
if (!is(Object == Duration)) {
return asyncAwaitImpl!(true, Callback, action, cancel, func)(Duration.max);
}
auto asyncAwait(Callback, alias action, alias cancel, string func = __FUNCTION__)(Duration timeout)
{
alias CB = ParameterTypeTuple!(__traits(getMember, Object, method))[$-1];
alias CBTypes = ParameterTypeTuple!CB;
return asyncAwaitImpl!(true, Callback, action, cancel, func)(timeout);
}
auto asyncAwaitUninterruptible(Callback, alias action, string func = __FUNCTION__)()
nothrow {
return asyncAwaitImpl!(false, Callback, action, (cb) { assert(false); }, func)(Duration.max);
}
auto asyncAwaitUninterruptible(Callback, alias action, alias cancel, string func = __FUNCTION__)(Duration timeout)
nothrow {
assert(timeout >= 0.seconds);
asyncAwaitImpl!(false, Callback, action, cancel, func)(timeout);
}
private auto asyncAwaitImpl(bool interruptible, Callback, alias action, alias cancel, string func)(Duration timeout)
@safe if (!is(Object == Duration)) {
alias CBTypes = ParameterTypeTuple!Callback;
assert(timeout >= 0.seconds);
assert(timeout == Duration.max, "TODO!");
bool fired = false;
CBTypes ret;
@ -21,25 +45,28 @@ auto asyncAwait(string method, Object, ARGS...)(Object object, ARGS args)
logTrace("Got result.");
fired = true;
ret = params;
if (t != Task.init)
resumeTask(t);
if (t != Task.init) switchToTask(t);
}
logTrace("Calling %s...", method);
__traits(getMember, object, method)(args, &callback);
scope cbdel = &callback;
logTrace("Calling async function in "~func);
action(cbdel);
if (!fired) {
logTrace("Need to wait...");
t = Task.getThis();
do yieldForEvent();
while (!fired);
do {
static if (interruptible) {
bool interrupted = false;
hibernate(() @safe nothrow {
cancel(cbdel);
interrupted = true;
});
if (interrupted)
throw new InterruptException; // FIXME: the original operation needs to be stopped! or the callback will still be called"
} else hibernate();
} while (!fired);
}
logTrace("Return result.");
return tuple(ret);
}
auto asyncAwait(string method, Object, ARGS...)(Duration timeout, Object object, ARGS args)
{
assert(timeout >= 0.seconds);
if (timeout == Duration.max) return asyncAwait(object, args);
else assert(false, "TODO!");
}