eve.backend.linux.uring

Linux runtime-selected Layer 0 backend.

On kernels that allow io_uring, this module exposes a real io_uring-backed readiness poller. When setup is rejected or unavailable it falls back to the reliable epoll backend so higher layers still have a usable Linux path.

var requestedRingEntries

enum OperationKind

struct OsPoller

fn nativeMaskFromResult probeIoUringSupport toNativeMask

Types 2

private enumOperationKind : ubyte

POLL = 1

REMOVE = 2

structOsPoller

Linux Layer 0 poller that prefers io_uring and falls back to epoll when the runtime rejects io_uring setup.

Fields

eve.backend.linux.epoll.OsPoller _fallback

bool _usingFallback

bool _ioUringAvailable

int _probeError

int _fd

void * _sqRing

void * _cqRing

void * _sqesRegion

size_t _sqRingLength

size_t _cqRingLength

size_t _sqesLength

bool _singleMmap

shared(uint) * _sqHead

shared(uint) * _sqTail

shared(uint) * _sqRingMask

shared(uint) * _sqRingEntries

shared(uint) * _sqArray

io_uring_sqe * _sqes

shared(uint) * _cqHead

shared(uint) * _cqTail

shared(uint) * _cqRingMask

shared(uint) * _cqRingEntries

io_uring_cqe * _cqes

Registration * _registrations

size_t _registrationCapacity

NativeEvent * _pendingEvents

size_t _pendingHead

size_t _pendingCount

ulong _submitSequence

Methods

uint load(shared(uint) * value) @trusted nothrow @nogc

void store(shared(uint) * value, uint payload) @trusted nothrow @nogc

ulong makeOperationId(uint slotIndex, OperationKind kind, ulong sequence) pure @safe nothrow @nogc

OperationKind operationKind(ulong userData) pure @safe nothrow @nogc

uint operationSlot(ulong userData) pure @safe nothrow @nogc

size_t maxSize(size_t left, size_t right) pure @safe nothrow @nogc

size_t pendingIndex(size_t offset) const pure @safe nothrow @nogc

Registration slot(uint index) ref @trusted nothrow @nogc

const(Registration) slot(uint index) ref const @trusted nothrow @nogc

int initializeIoUring() @trusted nothrow @nogc

void cleanupIoUring() @trusted nothrow @nogc

int submit(uint count) @trusted nothrow @nogc

io_uring_sqe * acquireSqe() @trusted nothrow @nogc

int findRegistration(Handle handle) const @safe nothrow @nogc

int findFreeRegistration() const @safe nothrow @nogc

ulong nextOperationId(uint slotIndex, OperationKind kind) @safe nothrow @nogc

int submitPollAdd(uint slotIndex) @trusted nothrow @nogc

int submitPollRemove(ulong targetUserData, ulong userData) @trusted nothrow @nogc

bool queueEvent(NativeEvent event) @trusted nothrow @nogc

int flushPending(scope NativeEvent[] nativeEvents) @trusted nothrow @nogc

int waitForRing(int timeoutMs) @trusted nothrow @nogc

size_t activeRegistrationCount() const @safe nothrow @nogc

bool processCompletion(ref  const(io_uring_cqe)  cqe,  scope  NativeEvent[]  output,  ref  int  written,  ulong  awaitedUserData,  ref  int  awaitedResult)

@trusted nothrow @nogc

bool drainCompletions(scope  NativeEvent[]  output,  ref  int  written,  ulong  awaitedUserData,  ref  int  awaitedResult)

@trusted nothrow @nogc

int waitForOperation(ulong awaitedUserData) @trusted nothrow @nogc

OsPoller create() @trusted nothrow @nogcCreate a new Linux poller.

bool isValid() @property const pure @safe nothrow @nogcCheck whether the active backend was created successfully.

bool ioUringAvailable() @property const pure @safe nothrow @nogcReport whether `io_uring` is active for this poller instance.

bool usingFallback() @property const pure @safe nothrow @nogcReport whether this poller instance is using the `epoll` fallback path.

int probeError() @property const pure @safe nothrow @nogcReturn the last `io_uring` setup error.

Handle handle() @property const pure @safe nothrow @nogcReturn the native handle wrapper for the active backend.

int dispose() @trusted nothrow @nogcDispose the active backend state.

int registerHandle(Handle handle, IoInterest interest, ulong userData) @trusted nothrow @nogcRegister a handle with the active backend.

int modifyHandle(Handle handle, IoInterest interest, ulong userData) @trusted nothrow @nogcModify the interest mask and user data for a registered handle.

int unregisterHandle(Handle handle) @trusted nothrow @nogcRemove a handle from the active backend.

int wait(scope NativeEvent[] nativeEvents, int timeoutMs) @trusted nothrow @nogcWait for native events from the active backend.

OsEvent translate(ref const(NativeEvent) nativeEvent) pure @safe nothrow @nogcTranslate a native backend event into the shared Layer 0 event shape.

IoReady translateReady(uint nativeMask) pure @safe nothrow @nogcTranslate a native readiness mask into shared readiness flags.

Nested Templates

Registration

Functions 3

private fnushort toNativeMask(IoInterest interest) pure @safe nothrow @nogc

private fnuint nativeMaskFromResult(int result) pure @safe nothrow @nogc

private fnint probeIoUringSupport() @trusted nothrow @nogc

Variables 1

private enumvarrequestedRingEntries = 1024u