mirror of
https://codeberg.org/ziglang/zig.git
synced 2025-12-06 13:54:21 +00:00
2b5306a94b
This only shows in release mode, the compiler tries to preserve some value in rdi, but that gets replaced inside the fiber. This would not happen in the C calling convention, but in these normal Zig functions, it can happen.
1618 lines
56 KiB
Zig
1618 lines
56 KiB
Zig
const std = @import("../std.zig");
|
|
const builtin = @import("builtin");
|
|
const assert = std.debug.assert;
|
|
const Allocator = std.mem.Allocator;
|
|
const Io = std.Io;
|
|
const EventLoop = @This();
|
|
const Alignment = std.mem.Alignment;
|
|
const IoUring = std.os.linux.IoUring;
|
|
|
|
/// Must be a thread-safe allocator.
|
|
gpa: Allocator,
|
|
main_fiber_buffer: [@sizeOf(Fiber) + Fiber.max_result_size]u8 align(@alignOf(Fiber)),
|
|
threads: Thread.List,
|
|
detached: struct {
|
|
mutex: std.Io.Mutex,
|
|
list: std.DoublyLinkedList,
|
|
},
|
|
|
|
/// Empirically saw >128KB being used by the self-hosted backend to panic.
|
|
const idle_stack_size = 256 * 1024;
|
|
|
|
const max_idle_search = 4;
|
|
const max_steal_ready_search = 4;
|
|
|
|
const io_uring_entries = 64;
|
|
|
|
const Thread = struct {
|
|
thread: std.Thread,
|
|
idle_context: Context,
|
|
current_context: *Context,
|
|
ready_queue: ?*Fiber,
|
|
io_uring: IoUring,
|
|
idle_search_index: u32,
|
|
steal_ready_search_index: u32,
|
|
|
|
const canceling: ?*Thread = @ptrFromInt(@alignOf(Thread));
|
|
|
|
threadlocal var self: *Thread = undefined;
|
|
|
|
fn current() *Thread {
|
|
return self;
|
|
}
|
|
|
|
fn currentFiber(thread: *Thread) *Fiber {
|
|
return @fieldParentPtr("context", thread.current_context);
|
|
}
|
|
|
|
const List = struct {
|
|
allocated: []Thread,
|
|
reserved: u32,
|
|
active: u32,
|
|
};
|
|
};
|
|
|
|
const Fiber = struct {
|
|
required_align: void align(4),
|
|
context: Context,
|
|
awaiter: ?*Fiber,
|
|
queue_next: ?*Fiber,
|
|
cancel_thread: ?*Thread,
|
|
awaiting_completions: std.StaticBitSet(3),
|
|
|
|
const finished: ?*Fiber = @ptrFromInt(@alignOf(Thread));
|
|
|
|
const max_result_align: Alignment = .@"16";
|
|
const max_result_size = max_result_align.forward(64);
|
|
/// This includes any stack realignments that need to happen, and also the
|
|
/// initial frame return address slot and argument frame, depending on target.
|
|
const min_stack_size = 4 * 1024 * 1024;
|
|
const max_context_align: Alignment = .@"16";
|
|
const max_context_size = max_context_align.forward(1024);
|
|
const max_closure_size: usize = @max(@sizeOf(AsyncClosure), @sizeOf(DetachedClosure));
|
|
const max_closure_align: Alignment = .max(.of(AsyncClosure), .of(DetachedClosure));
|
|
const allocation_size = std.mem.alignForward(
|
|
usize,
|
|
max_closure_align.max(max_context_align).forward(
|
|
max_result_align.forward(@sizeOf(Fiber)) + max_result_size + min_stack_size,
|
|
) + max_closure_size + max_context_size,
|
|
std.heap.page_size_max,
|
|
);
|
|
|
|
fn allocate(el: *EventLoop) error{OutOfMemory}!*Fiber {
|
|
return @ptrCast(try el.gpa.alignedAlloc(u8, .of(Fiber), allocation_size));
|
|
}
|
|
|
|
fn allocatedSlice(f: *Fiber) []align(@alignOf(Fiber)) u8 {
|
|
return @as([*]align(@alignOf(Fiber)) u8, @ptrCast(f))[0..allocation_size];
|
|
}
|
|
|
|
fn allocatedEnd(f: *Fiber) [*]u8 {
|
|
const allocated_slice = f.allocatedSlice();
|
|
return allocated_slice[allocated_slice.len..].ptr;
|
|
}
|
|
|
|
fn resultPointer(f: *Fiber, comptime Result: type) *Result {
|
|
return @ptrCast(@alignCast(f.resultBytes(.of(Result))));
|
|
}
|
|
|
|
fn resultBytes(f: *Fiber, alignment: Alignment) [*]u8 {
|
|
return @ptrFromInt(alignment.forward(@intFromPtr(f) + @sizeOf(Fiber)));
|
|
}
|
|
|
|
fn enterCancelRegion(fiber: *Fiber, thread: *Thread) error{Canceled}!void {
|
|
if (@cmpxchgStrong(
|
|
?*Thread,
|
|
&fiber.cancel_thread,
|
|
null,
|
|
thread,
|
|
.acq_rel,
|
|
.acquire,
|
|
)) |cancel_thread| {
|
|
assert(cancel_thread == Thread.canceling);
|
|
return error.Canceled;
|
|
}
|
|
}
|
|
|
|
fn exitCancelRegion(fiber: *Fiber, thread: *Thread) void {
|
|
if (@cmpxchgStrong(
|
|
?*Thread,
|
|
&fiber.cancel_thread,
|
|
thread,
|
|
null,
|
|
.acq_rel,
|
|
.acquire,
|
|
)) |cancel_thread| assert(cancel_thread == Thread.canceling);
|
|
}
|
|
|
|
const Queue = struct { head: *Fiber, tail: *Fiber };
|
|
};
|
|
|
|
fn recycle(el: *EventLoop, fiber: *Fiber) void {
|
|
std.log.debug("recyling {*}", .{fiber});
|
|
assert(fiber.queue_next == null);
|
|
el.gpa.free(fiber.allocatedSlice());
|
|
}
|
|
|
|
pub fn io(el: *EventLoop) Io {
|
|
return .{
|
|
.userdata = el,
|
|
.vtable = &.{
|
|
.async = async,
|
|
.concurrent = concurrent,
|
|
.await = await,
|
|
.asyncDetached = asyncDetached,
|
|
.select = select,
|
|
.cancel = cancel,
|
|
.cancelRequested = cancelRequested,
|
|
|
|
.mutexLock = mutexLock,
|
|
.mutexUnlock = mutexUnlock,
|
|
|
|
.conditionWait = conditionWait,
|
|
.conditionWake = conditionWake,
|
|
|
|
.createFile = createFile,
|
|
.fileOpen = fileOpen,
|
|
.fileClose = fileClose,
|
|
.pread = pread,
|
|
.pwrite = pwrite,
|
|
|
|
.now = now,
|
|
.sleep = sleep,
|
|
},
|
|
};
|
|
}
|
|
|
|
pub fn init(el: *EventLoop, gpa: Allocator) !void {
|
|
const threads_size = @max(std.Thread.getCpuCount() catch 1, 1) * @sizeOf(Thread);
|
|
const idle_stack_end_offset = std.mem.alignForward(usize, threads_size + idle_stack_size, std.heap.page_size_max);
|
|
const allocated_slice = try gpa.alignedAlloc(u8, .of(Thread), idle_stack_end_offset);
|
|
errdefer gpa.free(allocated_slice);
|
|
el.* = .{
|
|
.gpa = gpa,
|
|
.main_fiber_buffer = undefined,
|
|
.threads = .{
|
|
.allocated = @ptrCast(allocated_slice[0..threads_size]),
|
|
.reserved = 1,
|
|
.active = 1,
|
|
},
|
|
.detached = .{
|
|
.mutex = .init,
|
|
.list = .{},
|
|
},
|
|
};
|
|
const main_fiber: *Fiber = @ptrCast(&el.main_fiber_buffer);
|
|
main_fiber.* = .{
|
|
.required_align = {},
|
|
.context = undefined,
|
|
.awaiter = null,
|
|
.queue_next = null,
|
|
.cancel_thread = null,
|
|
.awaiting_completions = .initEmpty(),
|
|
};
|
|
const main_thread = &el.threads.allocated[0];
|
|
Thread.self = main_thread;
|
|
const idle_stack_end: [*]align(16) usize = @ptrCast(@alignCast(allocated_slice[idle_stack_end_offset..].ptr));
|
|
(idle_stack_end - 1)[0..1].* = .{@intFromPtr(el)};
|
|
main_thread.* = .{
|
|
.thread = undefined,
|
|
.idle_context = switch (builtin.cpu.arch) {
|
|
.aarch64 => .{
|
|
.sp = @intFromPtr(idle_stack_end),
|
|
.fp = 0,
|
|
.pc = @intFromPtr(&mainIdleEntry),
|
|
},
|
|
.x86_64 => .{
|
|
.rsp = @intFromPtr(idle_stack_end - 1),
|
|
.rbp = 0,
|
|
.rip = @intFromPtr(&mainIdleEntry),
|
|
},
|
|
else => @compileError("unimplemented architecture"),
|
|
},
|
|
.current_context = &main_fiber.context,
|
|
.ready_queue = null,
|
|
.io_uring = try IoUring.init(io_uring_entries, 0),
|
|
.idle_search_index = 1,
|
|
.steal_ready_search_index = 1,
|
|
};
|
|
errdefer main_thread.io_uring.deinit();
|
|
std.log.debug("created main idle {*}", .{&main_thread.idle_context});
|
|
std.log.debug("created main {*}", .{main_fiber});
|
|
}
|
|
|
|
pub fn deinit(el: *EventLoop) void {
|
|
while (true) cancel(el, detached_future: {
|
|
el.detached.mutex.lock(el.io()) catch |err| switch (err) {
|
|
error.Canceled => unreachable, // main fiber cannot be canceled
|
|
};
|
|
defer el.detached.mutex.unlock(el.io());
|
|
const detached: *DetachedClosure = @fieldParentPtr(
|
|
"detached_queue_node",
|
|
el.detached.list.pop() orelse break,
|
|
);
|
|
// notify the detached fiber that it is no longer allowed to recycle itself
|
|
detached.detached_queue_node = .{
|
|
.prev = &detached.detached_queue_node,
|
|
.next = &detached.detached_queue_node,
|
|
};
|
|
break :detached_future @ptrCast(detached.fiber);
|
|
}, &.{}, .@"1");
|
|
const active_threads = @atomicLoad(u32, &el.threads.active, .acquire);
|
|
for (el.threads.allocated[0..active_threads]) |*thread| {
|
|
const ready_fiber = @atomicLoad(?*Fiber, &thread.ready_queue, .monotonic);
|
|
assert(ready_fiber == null or ready_fiber == Fiber.finished); // pending async
|
|
}
|
|
el.yield(null, .exit);
|
|
const allocated_ptr: [*]align(@alignOf(Thread)) u8 = @ptrCast(@alignCast(el.threads.allocated.ptr));
|
|
const idle_stack_end_offset = std.mem.alignForward(usize, el.threads.allocated.len * @sizeOf(Thread) + idle_stack_size, std.heap.page_size_max);
|
|
for (el.threads.allocated[1..active_threads]) |*thread| thread.thread.join();
|
|
el.gpa.free(allocated_ptr[0..idle_stack_end_offset]);
|
|
el.* = undefined;
|
|
}
|
|
|
|
fn findReadyFiber(el: *EventLoop, thread: *Thread) ?*Fiber {
|
|
if (@atomicRmw(?*Fiber, &thread.ready_queue, .Xchg, Fiber.finished, .acquire)) |ready_fiber| {
|
|
@atomicStore(?*Fiber, &thread.ready_queue, ready_fiber.queue_next, .release);
|
|
ready_fiber.queue_next = null;
|
|
return ready_fiber;
|
|
}
|
|
const active_threads = @atomicLoad(u32, &el.threads.active, .acquire);
|
|
for (0..@min(max_steal_ready_search, active_threads)) |_| {
|
|
defer thread.steal_ready_search_index += 1;
|
|
if (thread.steal_ready_search_index == active_threads) thread.steal_ready_search_index = 0;
|
|
const steal_ready_search_thread = &el.threads.allocated[0..active_threads][thread.steal_ready_search_index];
|
|
if (steal_ready_search_thread == thread) continue;
|
|
const ready_fiber = @atomicLoad(?*Fiber, &steal_ready_search_thread.ready_queue, .acquire) orelse continue;
|
|
if (ready_fiber == Fiber.finished) continue;
|
|
if (@cmpxchgWeak(
|
|
?*Fiber,
|
|
&steal_ready_search_thread.ready_queue,
|
|
ready_fiber,
|
|
null,
|
|
.acquire,
|
|
.monotonic,
|
|
)) |_| continue;
|
|
@atomicStore(?*Fiber, &thread.ready_queue, ready_fiber.queue_next, .release);
|
|
ready_fiber.queue_next = null;
|
|
return ready_fiber;
|
|
}
|
|
// couldn't find anything to do, so we are now open for business
|
|
@atomicStore(?*Fiber, &thread.ready_queue, null, .monotonic);
|
|
return null;
|
|
}
|
|
|
|
fn yield(el: *EventLoop, maybe_ready_fiber: ?*Fiber, pending_task: SwitchMessage.PendingTask) void {
|
|
const thread: *Thread = .current();
|
|
const ready_context = if (maybe_ready_fiber orelse el.findReadyFiber(thread)) |ready_fiber|
|
|
&ready_fiber.context
|
|
else
|
|
&thread.idle_context;
|
|
const message: SwitchMessage = .{
|
|
.contexts = .{
|
|
.prev = thread.current_context,
|
|
.ready = ready_context,
|
|
},
|
|
.pending_task = pending_task,
|
|
};
|
|
std.log.debug("switching from {*} to {*}", .{ message.contexts.prev, message.contexts.ready });
|
|
contextSwitch(&message).handle(el);
|
|
}
|
|
|
|
fn schedule(el: *EventLoop, thread: *Thread, ready_queue: Fiber.Queue) void {
|
|
{
|
|
var fiber = ready_queue.head;
|
|
while (true) {
|
|
std.log.debug("scheduling {*}", .{fiber});
|
|
fiber = fiber.queue_next orelse break;
|
|
}
|
|
assert(fiber == ready_queue.tail);
|
|
}
|
|
// shared fields of previous `Thread` must be initialized before later ones are marked as active
|
|
const new_thread_index = @atomicLoad(u32, &el.threads.active, .acquire);
|
|
for (0..@min(max_idle_search, new_thread_index)) |_| {
|
|
defer thread.idle_search_index += 1;
|
|
if (thread.idle_search_index == new_thread_index) thread.idle_search_index = 0;
|
|
const idle_search_thread = &el.threads.allocated[0..new_thread_index][thread.idle_search_index];
|
|
if (idle_search_thread == thread) continue;
|
|
if (@cmpxchgWeak(
|
|
?*Fiber,
|
|
&idle_search_thread.ready_queue,
|
|
null,
|
|
ready_queue.head,
|
|
.release,
|
|
.monotonic,
|
|
)) |_| continue;
|
|
getSqe(&thread.io_uring).* = .{
|
|
.opcode = .MSG_RING,
|
|
.flags = std.os.linux.IOSQE_CQE_SKIP_SUCCESS,
|
|
.ioprio = 0,
|
|
.fd = idle_search_thread.io_uring.fd,
|
|
.off = @intFromEnum(Completion.UserData.wakeup),
|
|
.addr = 0,
|
|
.len = 0,
|
|
.rw_flags = 0,
|
|
.user_data = @intFromEnum(Completion.UserData.wakeup),
|
|
.buf_index = 0,
|
|
.personality = 0,
|
|
.splice_fd_in = 0,
|
|
.addr3 = 0,
|
|
.resv = 0,
|
|
};
|
|
return;
|
|
}
|
|
spawn_thread: {
|
|
// previous failed reservations must have completed before retrying
|
|
if (new_thread_index == el.threads.allocated.len or @cmpxchgWeak(
|
|
u32,
|
|
&el.threads.reserved,
|
|
new_thread_index,
|
|
new_thread_index + 1,
|
|
.acquire,
|
|
.monotonic,
|
|
) != null) break :spawn_thread;
|
|
const new_thread = &el.threads.allocated[new_thread_index];
|
|
const next_thread_index = new_thread_index + 1;
|
|
new_thread.* = .{
|
|
.thread = undefined,
|
|
.idle_context = undefined,
|
|
.current_context = &new_thread.idle_context,
|
|
.ready_queue = ready_queue.head,
|
|
.io_uring = IoUring.init(io_uring_entries, 0) catch |err| {
|
|
@atomicStore(u32, &el.threads.reserved, new_thread_index, .release);
|
|
// no more access to `thread` after giving up reservation
|
|
std.log.warn("unable to create worker thread due to io_uring init failure: {s}", .{@errorName(err)});
|
|
break :spawn_thread;
|
|
},
|
|
.idle_search_index = 0,
|
|
.steal_ready_search_index = 0,
|
|
};
|
|
new_thread.thread = std.Thread.spawn(.{
|
|
.stack_size = idle_stack_size,
|
|
.allocator = el.gpa,
|
|
}, threadEntry, .{ el, new_thread_index }) catch |err| {
|
|
new_thread.io_uring.deinit();
|
|
@atomicStore(u32, &el.threads.reserved, new_thread_index, .release);
|
|
// no more access to `thread` after giving up reservation
|
|
std.log.warn("unable to create worker thread due spawn failure: {s}", .{@errorName(err)});
|
|
break :spawn_thread;
|
|
};
|
|
// shared fields of `Thread` must be initialized before being marked active
|
|
@atomicStore(u32, &el.threads.active, next_thread_index, .release);
|
|
return;
|
|
}
|
|
// nobody wanted it, so just queue it on ourselves
|
|
while (@cmpxchgWeak(
|
|
?*Fiber,
|
|
&thread.ready_queue,
|
|
ready_queue.tail.queue_next,
|
|
ready_queue.head,
|
|
.acq_rel,
|
|
.acquire,
|
|
)) |old_head| ready_queue.tail.queue_next = old_head;
|
|
}
|
|
|
|
fn mainIdle(el: *EventLoop, message: *const SwitchMessage) callconv(.withStackAlign(.c, @max(@alignOf(Thread), @alignOf(Context)))) noreturn {
|
|
message.handle(el);
|
|
el.idle(&el.threads.allocated[0]);
|
|
el.yield(@ptrCast(&el.main_fiber_buffer), .nothing);
|
|
unreachable; // switched to dead fiber
|
|
}
|
|
|
|
fn threadEntry(el: *EventLoop, index: u32) void {
|
|
const thread: *Thread = &el.threads.allocated[index];
|
|
Thread.self = thread;
|
|
std.log.debug("created thread idle {*}", .{&thread.idle_context});
|
|
el.idle(thread);
|
|
}
|
|
|
|
const Completion = struct {
|
|
const UserData = enum(usize) {
|
|
unused,
|
|
wakeup,
|
|
cleanup,
|
|
exit,
|
|
/// *Fiber
|
|
_,
|
|
};
|
|
result: i32,
|
|
flags: u32,
|
|
};
|
|
|
|
fn idle(el: *EventLoop, thread: *Thread) void {
|
|
var maybe_ready_fiber: ?*Fiber = null;
|
|
while (true) {
|
|
while (maybe_ready_fiber orelse el.findReadyFiber(thread)) |ready_fiber| {
|
|
el.yield(ready_fiber, .nothing);
|
|
maybe_ready_fiber = null;
|
|
}
|
|
_ = thread.io_uring.submit_and_wait(1) catch |err| switch (err) {
|
|
error.SignalInterrupt => std.log.warn("submit_and_wait failed with SignalInterrupt", .{}),
|
|
else => |e| @panic(@errorName(e)),
|
|
};
|
|
var cqes_buffer: [io_uring_entries]std.os.linux.io_uring_cqe = undefined;
|
|
var maybe_ready_queue: ?Fiber.Queue = null;
|
|
for (cqes_buffer[0 .. thread.io_uring.copy_cqes(&cqes_buffer, 0) catch |err| switch (err) {
|
|
error.SignalInterrupt => cqes_len: {
|
|
std.log.warn("copy_cqes failed with SignalInterrupt", .{});
|
|
break :cqes_len 0;
|
|
},
|
|
else => |e| @panic(@errorName(e)),
|
|
}]) |cqe| switch (@as(Completion.UserData, @enumFromInt(cqe.user_data))) {
|
|
.unused => unreachable, // bad submission queued?
|
|
.wakeup => {},
|
|
.cleanup => @panic("failed to notify other threads that we are exiting"),
|
|
.exit => {
|
|
assert(maybe_ready_fiber == null and maybe_ready_queue == null); // pending async
|
|
return;
|
|
},
|
|
_ => switch (errno(cqe.res)) {
|
|
.INTR => getSqe(&thread.io_uring).* = .{
|
|
.opcode = .ASYNC_CANCEL,
|
|
.flags = std.os.linux.IOSQE_CQE_SKIP_SUCCESS,
|
|
.ioprio = 0,
|
|
.fd = 0,
|
|
.off = 0,
|
|
.addr = cqe.user_data,
|
|
.len = 0,
|
|
.rw_flags = 0,
|
|
.user_data = @intFromEnum(Completion.UserData.wakeup),
|
|
.buf_index = 0,
|
|
.personality = 0,
|
|
.splice_fd_in = 0,
|
|
.addr3 = 0,
|
|
.resv = 0,
|
|
},
|
|
else => {
|
|
const fiber: *Fiber = @ptrFromInt(cqe.user_data);
|
|
assert(fiber.queue_next == null);
|
|
fiber.resultPointer(Completion).* = .{
|
|
.result = cqe.res,
|
|
.flags = cqe.flags,
|
|
};
|
|
if (maybe_ready_fiber == null) maybe_ready_fiber = fiber else if (maybe_ready_queue) |*ready_queue| {
|
|
ready_queue.tail.queue_next = fiber;
|
|
ready_queue.tail = fiber;
|
|
} else maybe_ready_queue = .{ .head = fiber, .tail = fiber };
|
|
},
|
|
},
|
|
};
|
|
if (maybe_ready_queue) |ready_queue| el.schedule(thread, ready_queue);
|
|
}
|
|
}
|
|
|
|
const SwitchMessage = struct {
|
|
contexts: extern struct {
|
|
prev: *Context,
|
|
ready: *Context,
|
|
},
|
|
pending_task: PendingTask,
|
|
|
|
const PendingTask = union(enum) {
|
|
nothing,
|
|
reschedule,
|
|
recycle,
|
|
register_awaiter: *?*Fiber,
|
|
register_select: []const *Io.AnyFuture,
|
|
mutex_lock: struct {
|
|
prev_state: Io.Mutex.State,
|
|
mutex: *Io.Mutex,
|
|
},
|
|
condition_wait: struct {
|
|
cond: *Io.Condition,
|
|
mutex: *Io.Mutex,
|
|
},
|
|
exit,
|
|
};
|
|
|
|
fn handle(message: *const SwitchMessage, el: *EventLoop) void {
|
|
const thread: *Thread = .current();
|
|
thread.current_context = message.contexts.ready;
|
|
switch (message.pending_task) {
|
|
.nothing => {},
|
|
.reschedule => if (message.contexts.prev != &thread.idle_context) {
|
|
const prev_fiber: *Fiber = @alignCast(@fieldParentPtr("context", message.contexts.prev));
|
|
assert(prev_fiber.queue_next == null);
|
|
el.schedule(thread, .{ .head = prev_fiber, .tail = prev_fiber });
|
|
},
|
|
.recycle => {
|
|
const prev_fiber: *Fiber = @alignCast(@fieldParentPtr("context", message.contexts.prev));
|
|
assert(prev_fiber.queue_next == null);
|
|
el.recycle(prev_fiber);
|
|
},
|
|
.register_awaiter => |awaiter| {
|
|
const prev_fiber: *Fiber = @alignCast(@fieldParentPtr("context", message.contexts.prev));
|
|
assert(prev_fiber.queue_next == null);
|
|
if (@atomicRmw(?*Fiber, awaiter, .Xchg, prev_fiber, .acq_rel) == Fiber.finished)
|
|
el.schedule(thread, .{ .head = prev_fiber, .tail = prev_fiber });
|
|
},
|
|
.register_select => |futures| {
|
|
const prev_fiber: *Fiber = @alignCast(@fieldParentPtr("context", message.contexts.prev));
|
|
assert(prev_fiber.queue_next == null);
|
|
for (futures) |any_future| {
|
|
const future_fiber: *Fiber = @ptrCast(@alignCast(any_future));
|
|
if (@atomicRmw(?*Fiber, &future_fiber.awaiter, .Xchg, prev_fiber, .acq_rel) == Fiber.finished) {
|
|
const closure: *AsyncClosure = .fromFiber(future_fiber);
|
|
if (!@atomicRmw(bool, &closure.already_awaited, .Xchg, true, .seq_cst)) {
|
|
el.schedule(thread, .{ .head = prev_fiber, .tail = prev_fiber });
|
|
}
|
|
}
|
|
}
|
|
},
|
|
.mutex_lock => |mutex_lock| {
|
|
const prev_fiber: *Fiber = @alignCast(@fieldParentPtr("context", message.contexts.prev));
|
|
assert(prev_fiber.queue_next == null);
|
|
var prev_state = mutex_lock.prev_state;
|
|
while (switch (prev_state) {
|
|
else => next_state: {
|
|
prev_fiber.queue_next = @ptrFromInt(@intFromEnum(prev_state));
|
|
break :next_state @cmpxchgWeak(
|
|
Io.Mutex.State,
|
|
&mutex_lock.mutex.state,
|
|
prev_state,
|
|
@enumFromInt(@intFromPtr(prev_fiber)),
|
|
.release,
|
|
.acquire,
|
|
);
|
|
},
|
|
.unlocked => @cmpxchgWeak(
|
|
Io.Mutex.State,
|
|
&mutex_lock.mutex.state,
|
|
.unlocked,
|
|
.locked_once,
|
|
.acquire,
|
|
.acquire,
|
|
) orelse {
|
|
prev_fiber.queue_next = null;
|
|
el.schedule(thread, .{ .head = prev_fiber, .tail = prev_fiber });
|
|
return;
|
|
},
|
|
}) |next_state| prev_state = next_state;
|
|
},
|
|
.condition_wait => |condition_wait| {
|
|
const prev_fiber: *Fiber = @alignCast(@fieldParentPtr("context", message.contexts.prev));
|
|
assert(prev_fiber.queue_next == null);
|
|
const cond_impl = prev_fiber.resultPointer(ConditionImpl);
|
|
cond_impl.* = .{
|
|
.tail = prev_fiber,
|
|
.event = .queued,
|
|
};
|
|
if (@cmpxchgStrong(
|
|
?*Fiber,
|
|
@as(*?*Fiber, @ptrCast(&condition_wait.cond.state)),
|
|
null,
|
|
prev_fiber,
|
|
.release,
|
|
.acquire,
|
|
)) |waiting_fiber| {
|
|
const waiting_cond_impl = waiting_fiber.?.resultPointer(ConditionImpl);
|
|
assert(waiting_cond_impl.tail.queue_next == null);
|
|
waiting_cond_impl.tail.queue_next = prev_fiber;
|
|
waiting_cond_impl.tail = prev_fiber;
|
|
}
|
|
condition_wait.mutex.unlock(el.io());
|
|
},
|
|
.exit => for (el.threads.allocated[0..@atomicLoad(u32, &el.threads.active, .acquire)]) |*each_thread| {
|
|
getSqe(&thread.io_uring).* = .{
|
|
.opcode = .MSG_RING,
|
|
.flags = std.os.linux.IOSQE_CQE_SKIP_SUCCESS,
|
|
.ioprio = 0,
|
|
.fd = each_thread.io_uring.fd,
|
|
.off = @intFromEnum(Completion.UserData.exit),
|
|
.addr = 0,
|
|
.len = 0,
|
|
.rw_flags = 0,
|
|
.user_data = @intFromEnum(Completion.UserData.cleanup),
|
|
.buf_index = 0,
|
|
.personality = 0,
|
|
.splice_fd_in = 0,
|
|
.addr3 = 0,
|
|
.resv = 0,
|
|
};
|
|
},
|
|
}
|
|
}
|
|
};
|
|
|
|
const Context = switch (builtin.cpu.arch) {
|
|
.aarch64 => extern struct {
|
|
sp: u64,
|
|
fp: u64,
|
|
pc: u64,
|
|
},
|
|
.x86_64 => extern struct {
|
|
rsp: u64,
|
|
rbp: u64,
|
|
rip: u64,
|
|
},
|
|
else => |arch| @compileError("unimplemented architecture: " ++ @tagName(arch)),
|
|
};
|
|
|
|
inline fn contextSwitch(message: *const SwitchMessage) *const SwitchMessage {
|
|
return @fieldParentPtr("contexts", switch (builtin.cpu.arch) {
|
|
.aarch64 => asm volatile (
|
|
\\ ldp x0, x2, [x1]
|
|
\\ ldr x3, [x2, #16]
|
|
\\ mov x4, sp
|
|
\\ stp x4, fp, [x0]
|
|
\\ adr x5, 0f
|
|
\\ ldp x4, fp, [x2]
|
|
\\ str x5, [x0, #16]
|
|
\\ mov sp, x4
|
|
\\ br x3
|
|
\\0:
|
|
: [received_message] "={x1}" (-> *const @FieldType(SwitchMessage, "contexts")),
|
|
: [message_to_send] "{x1}" (&message.contexts),
|
|
: .{
|
|
.x0 = true,
|
|
.x1 = true,
|
|
.x2 = true,
|
|
.x3 = true,
|
|
.x4 = true,
|
|
.x5 = true,
|
|
.x6 = true,
|
|
.x7 = true,
|
|
.x8 = true,
|
|
.x9 = true,
|
|
.x10 = true,
|
|
.x11 = true,
|
|
.x12 = true,
|
|
.x13 = true,
|
|
.x14 = true,
|
|
.x15 = true,
|
|
.x16 = true,
|
|
.x17 = true,
|
|
.x18 = true,
|
|
.x19 = true,
|
|
.x20 = true,
|
|
.x21 = true,
|
|
.x22 = true,
|
|
.x23 = true,
|
|
.x24 = true,
|
|
.x25 = true,
|
|
.x26 = true,
|
|
.x27 = true,
|
|
.x28 = true,
|
|
.x30 = true,
|
|
.z0 = true,
|
|
.z1 = true,
|
|
.z2 = true,
|
|
.z3 = true,
|
|
.z4 = true,
|
|
.z5 = true,
|
|
.z6 = true,
|
|
.z7 = true,
|
|
.z8 = true,
|
|
.z9 = true,
|
|
.z10 = true,
|
|
.z11 = true,
|
|
.z12 = true,
|
|
.z13 = true,
|
|
.z14 = true,
|
|
.z15 = true,
|
|
.z16 = true,
|
|
.z17 = true,
|
|
.z18 = true,
|
|
.z19 = true,
|
|
.z20 = true,
|
|
.z21 = true,
|
|
.z22 = true,
|
|
.z23 = true,
|
|
.z24 = true,
|
|
.z25 = true,
|
|
.z26 = true,
|
|
.z27 = true,
|
|
.z28 = true,
|
|
.z29 = true,
|
|
.z30 = true,
|
|
.z31 = true,
|
|
.p0 = true,
|
|
.p1 = true,
|
|
.p2 = true,
|
|
.p3 = true,
|
|
.p4 = true,
|
|
.p5 = true,
|
|
.p6 = true,
|
|
.p7 = true,
|
|
.p8 = true,
|
|
.p9 = true,
|
|
.p10 = true,
|
|
.p11 = true,
|
|
.p12 = true,
|
|
.p13 = true,
|
|
.p14 = true,
|
|
.p15 = true,
|
|
.fpcr = true,
|
|
.fpsr = true,
|
|
.ffr = true,
|
|
.memory = true,
|
|
}),
|
|
.x86_64 => asm volatile (
|
|
\\ movq 0(%%rsi), %%rax
|
|
\\ movq 8(%%rsi), %%rcx
|
|
\\ leaq 0f(%%rip), %%rdx
|
|
\\ movq %%rsp, 0(%%rax)
|
|
\\ movq %%rbp, 8(%%rax)
|
|
\\ movq %%rdx, 16(%%rax)
|
|
\\ movq 0(%%rcx), %%rsp
|
|
\\ movq 8(%%rcx), %%rbp
|
|
\\ jmpq *16(%%rcx)
|
|
\\0:
|
|
: [received_message] "={rsi}" (-> *const @FieldType(SwitchMessage, "contexts")),
|
|
: [message_to_send] "{rsi}" (&message.contexts),
|
|
: .{
|
|
.rax = true,
|
|
.rcx = true,
|
|
.rdx = true,
|
|
.rbx = true,
|
|
.rsi = true,
|
|
.rdi = true,
|
|
.r8 = true,
|
|
.r9 = true,
|
|
.r10 = true,
|
|
.r11 = true,
|
|
.r12 = true,
|
|
.r13 = true,
|
|
.r14 = true,
|
|
.r15 = true,
|
|
.mm0 = true,
|
|
.mm1 = true,
|
|
.mm2 = true,
|
|
.mm3 = true,
|
|
.mm4 = true,
|
|
.mm5 = true,
|
|
.mm6 = true,
|
|
.mm7 = true,
|
|
.zmm0 = true,
|
|
.zmm1 = true,
|
|
.zmm2 = true,
|
|
.zmm3 = true,
|
|
.zmm4 = true,
|
|
.zmm5 = true,
|
|
.zmm6 = true,
|
|
.zmm7 = true,
|
|
.zmm8 = true,
|
|
.zmm9 = true,
|
|
.zmm10 = true,
|
|
.zmm11 = true,
|
|
.zmm12 = true,
|
|
.zmm13 = true,
|
|
.zmm14 = true,
|
|
.zmm15 = true,
|
|
.zmm16 = true,
|
|
.zmm17 = true,
|
|
.zmm18 = true,
|
|
.zmm19 = true,
|
|
.zmm20 = true,
|
|
.zmm21 = true,
|
|
.zmm22 = true,
|
|
.zmm23 = true,
|
|
.zmm24 = true,
|
|
.zmm25 = true,
|
|
.zmm26 = true,
|
|
.zmm27 = true,
|
|
.zmm28 = true,
|
|
.zmm29 = true,
|
|
.zmm30 = true,
|
|
.zmm31 = true,
|
|
.fpsr = true,
|
|
.fpcr = true,
|
|
.mxcsr = true,
|
|
.rflags = true,
|
|
.dirflag = true,
|
|
.memory = true,
|
|
}),
|
|
else => |arch| @compileError("unimplemented architecture: " ++ @tagName(arch)),
|
|
});
|
|
}
|
|
|
|
fn mainIdleEntry() callconv(.naked) void {
|
|
switch (builtin.cpu.arch) {
|
|
.x86_64 => asm volatile (
|
|
\\ movq (%%rsp), %%rdi
|
|
\\ jmp %[mainIdle:P]
|
|
:
|
|
: [mainIdle] "X" (&mainIdle),
|
|
),
|
|
.aarch64 => asm volatile (
|
|
\\ ldr x0, [sp, #-8]
|
|
\\ b %[mainIdle]
|
|
:
|
|
: [mainIdle] "X" (&mainIdle),
|
|
),
|
|
else => |arch| @compileError("unimplemented architecture: " ++ @tagName(arch)),
|
|
}
|
|
}
|
|
|
|
fn fiberEntry() callconv(.naked) void {
|
|
switch (builtin.cpu.arch) {
|
|
.x86_64 => asm volatile (
|
|
\\ leaq 8(%%rsp), %%rdi
|
|
\\ jmpq *(%%rsp)
|
|
),
|
|
.aarch64 => asm volatile (
|
|
\\ mov x0, sp
|
|
\\ ldr x2, [sp, #-8]
|
|
\\ br x2
|
|
),
|
|
else => |arch| @compileError("unimplemented architecture: " ++ @tagName(arch)),
|
|
}
|
|
}
|
|
|
|
const AsyncClosure = struct {
|
|
event_loop: *EventLoop,
|
|
fiber: *Fiber,
|
|
start: *const fn (context: *const anyopaque, result: *anyopaque) void,
|
|
result_align: Alignment,
|
|
already_awaited: bool,
|
|
|
|
fn contextPointer(closure: *AsyncClosure) [*]align(Fiber.max_context_align.toByteUnits()) u8 {
|
|
return @alignCast(@as([*]u8, @ptrCast(closure)) + @sizeOf(AsyncClosure));
|
|
}
|
|
|
|
fn call(closure: *AsyncClosure, message: *const SwitchMessage) callconv(.withStackAlign(.c, @alignOf(AsyncClosure))) noreturn {
|
|
message.handle(closure.event_loop);
|
|
const fiber = closure.fiber;
|
|
std.log.debug("{*} performing async", .{fiber});
|
|
closure.start(closure.contextPointer(), fiber.resultBytes(closure.result_align));
|
|
const awaiter = @atomicRmw(?*Fiber, &fiber.awaiter, .Xchg, Fiber.finished, .acq_rel);
|
|
const ready_awaiter = r: {
|
|
const a = awaiter orelse break :r null;
|
|
if (@atomicRmw(bool, &closure.already_awaited, .Xchg, true, .acq_rel)) break :r null;
|
|
break :r a;
|
|
};
|
|
closure.event_loop.yield(ready_awaiter, .nothing);
|
|
unreachable; // switched to dead fiber
|
|
}
|
|
|
|
fn fromFiber(fiber: *Fiber) *AsyncClosure {
|
|
return @ptrFromInt(Fiber.max_context_align.max(.of(AsyncClosure)).backward(
|
|
@intFromPtr(fiber.allocatedEnd()) - Fiber.max_context_size,
|
|
) - @sizeOf(AsyncClosure));
|
|
}
|
|
};
|
|
|
|
fn async(
|
|
userdata: ?*anyopaque,
|
|
result: []u8,
|
|
result_alignment: Alignment,
|
|
context: []const u8,
|
|
context_alignment: Alignment,
|
|
start: *const fn (context: *const anyopaque, result: *anyopaque) void,
|
|
) ?*std.Io.AnyFuture {
|
|
return concurrent(userdata, result.len, result_alignment, context, context_alignment, start) catch {
|
|
start(context.ptr, result.ptr);
|
|
return null;
|
|
};
|
|
}
|
|
|
|
fn concurrent(
|
|
userdata: ?*anyopaque,
|
|
result_len: usize,
|
|
result_alignment: Alignment,
|
|
context: []const u8,
|
|
context_alignment: Alignment,
|
|
start: *const fn (context: *const anyopaque, result: *anyopaque) void,
|
|
) error{OutOfMemory}!*std.Io.AnyFuture {
|
|
assert(result_alignment.compare(.lte, Fiber.max_result_align)); // TODO
|
|
assert(context_alignment.compare(.lte, Fiber.max_context_align)); // TODO
|
|
assert(result_len <= Fiber.max_result_size); // TODO
|
|
assert(context.len <= Fiber.max_context_size); // TODO
|
|
|
|
const event_loop: *EventLoop = @ptrCast(@alignCast(userdata));
|
|
const fiber = try Fiber.allocate(event_loop);
|
|
std.log.debug("allocated {*}", .{fiber});
|
|
|
|
const closure: *AsyncClosure = .fromFiber(fiber);
|
|
const stack_end: [*]align(16) usize = @ptrCast(@alignCast(closure));
|
|
(stack_end - 1)[0..1].* = .{@intFromPtr(&AsyncClosure.call)};
|
|
fiber.* = .{
|
|
.required_align = {},
|
|
.context = switch (builtin.cpu.arch) {
|
|
.x86_64 => .{
|
|
.rsp = @intFromPtr(stack_end - 1),
|
|
.rbp = 0,
|
|
.rip = @intFromPtr(&fiberEntry),
|
|
},
|
|
.aarch64 => .{
|
|
.sp = @intFromPtr(stack_end),
|
|
.fp = 0,
|
|
.pc = @intFromPtr(&fiberEntry),
|
|
},
|
|
else => |arch| @compileError("unimplemented architecture: " ++ @tagName(arch)),
|
|
},
|
|
.awaiter = null,
|
|
.queue_next = null,
|
|
.cancel_thread = null,
|
|
.awaiting_completions = .initEmpty(),
|
|
};
|
|
closure.* = .{
|
|
.event_loop = event_loop,
|
|
.fiber = fiber,
|
|
.start = start,
|
|
.result_align = result_alignment,
|
|
.already_awaited = false,
|
|
};
|
|
@memcpy(closure.contextPointer(), context);
|
|
|
|
event_loop.schedule(.current(), .{ .head = fiber, .tail = fiber });
|
|
return @ptrCast(fiber);
|
|
}
|
|
|
|
const DetachedClosure = struct {
|
|
event_loop: *EventLoop,
|
|
fiber: *Fiber,
|
|
start: *const fn (context: *const anyopaque) void,
|
|
detached_queue_node: std.DoublyLinkedList.Node,
|
|
|
|
fn contextPointer(closure: *DetachedClosure) [*]align(Fiber.max_context_align.toByteUnits()) u8 {
|
|
return @alignCast(@as([*]u8, @ptrCast(closure)) + @sizeOf(DetachedClosure));
|
|
}
|
|
|
|
fn call(closure: *DetachedClosure, message: *const SwitchMessage) callconv(.withStackAlign(.c, @alignOf(DetachedClosure))) noreturn {
|
|
message.handle(closure.event_loop);
|
|
std.log.debug("{*} performing async detached", .{closure.fiber});
|
|
closure.start(closure.contextPointer());
|
|
const awaiter = @atomicRmw(?*Fiber, &closure.fiber.awaiter, .Xchg, Fiber.finished, .acq_rel);
|
|
closure.event_loop.yield(awaiter, pending_task: {
|
|
closure.event_loop.detached.mutex.lock(closure.event_loop.io()) catch |err| switch (err) {
|
|
error.Canceled => break :pending_task .nothing,
|
|
};
|
|
defer closure.event_loop.detached.mutex.unlock(closure.event_loop.io());
|
|
if (closure.detached_queue_node.next == &closure.detached_queue_node) break :pending_task .nothing;
|
|
closure.event_loop.detached.list.remove(&closure.detached_queue_node);
|
|
break :pending_task .recycle;
|
|
});
|
|
unreachable; // switched to dead fiber
|
|
}
|
|
};
|
|
|
|
fn asyncDetached(
|
|
userdata: ?*anyopaque,
|
|
context: []const u8,
|
|
context_alignment: std.mem.Alignment,
|
|
start: *const fn (context: *const anyopaque) void,
|
|
) void {
|
|
assert(context_alignment.compare(.lte, Fiber.max_context_align)); // TODO
|
|
assert(context.len <= Fiber.max_context_size); // TODO
|
|
|
|
const event_loop: *EventLoop = @ptrCast(@alignCast(userdata));
|
|
const fiber = Fiber.allocate(event_loop) catch {
|
|
start(context.ptr);
|
|
return;
|
|
};
|
|
std.log.debug("allocated {*}", .{fiber});
|
|
|
|
const current_thread: *Thread = .current();
|
|
const closure: *DetachedClosure = @ptrFromInt(Fiber.max_context_align.max(.of(DetachedClosure)).backward(
|
|
@intFromPtr(fiber.allocatedEnd()) - Fiber.max_context_size,
|
|
) - @sizeOf(DetachedClosure));
|
|
const stack_end: [*]align(16) usize = @ptrCast(@alignCast(closure));
|
|
(stack_end - 1)[0..1].* = .{@intFromPtr(&DetachedClosure.call)};
|
|
fiber.* = .{
|
|
.required_align = {},
|
|
.context = switch (builtin.cpu.arch) {
|
|
.x86_64 => .{
|
|
.rsp = @intFromPtr(stack_end - 1),
|
|
.rbp = 0,
|
|
.rip = @intFromPtr(&fiberEntry),
|
|
},
|
|
.aarch64 => .{
|
|
.sp = @intFromPtr(stack_end),
|
|
.fp = 0,
|
|
.pc = @intFromPtr(&fiberEntry),
|
|
},
|
|
else => |arch| @compileError("unimplemented architecture: " ++ @tagName(arch)),
|
|
},
|
|
.awaiter = null,
|
|
.queue_next = null,
|
|
.cancel_thread = null,
|
|
.awaiting_completions = .initEmpty(),
|
|
};
|
|
closure.* = .{
|
|
.event_loop = event_loop,
|
|
.fiber = fiber,
|
|
.start = start,
|
|
.detached_queue_node = .{},
|
|
};
|
|
{
|
|
event_loop.detached.mutex.lock(event_loop.io()) catch |err| switch (err) {
|
|
error.Canceled => {
|
|
event_loop.recycle(fiber);
|
|
start(context.ptr);
|
|
return;
|
|
},
|
|
};
|
|
defer event_loop.detached.mutex.unlock(event_loop.io());
|
|
event_loop.detached.list.append(&closure.detached_queue_node);
|
|
}
|
|
@memcpy(closure.contextPointer(), context);
|
|
|
|
event_loop.schedule(current_thread, .{ .head = fiber, .tail = fiber });
|
|
}
|
|
|
|
fn await(
|
|
userdata: ?*anyopaque,
|
|
any_future: *std.Io.AnyFuture,
|
|
result: []u8,
|
|
result_alignment: Alignment,
|
|
) void {
|
|
const event_loop: *EventLoop = @ptrCast(@alignCast(userdata));
|
|
const future_fiber: *Fiber = @ptrCast(@alignCast(any_future));
|
|
if (@atomicLoad(?*Fiber, &future_fiber.awaiter, .acquire) != Fiber.finished)
|
|
event_loop.yield(null, .{ .register_awaiter = &future_fiber.awaiter });
|
|
@memcpy(result, future_fiber.resultBytes(result_alignment));
|
|
event_loop.recycle(future_fiber);
|
|
}
|
|
|
|
fn select(userdata: ?*anyopaque, futures: []const *Io.AnyFuture) usize {
|
|
const el: *EventLoop = @ptrCast(@alignCast(userdata));
|
|
|
|
// Optimization to avoid the yield below.
|
|
for (futures, 0..) |any_future, i| {
|
|
const future_fiber: *Fiber = @ptrCast(@alignCast(any_future));
|
|
if (@atomicLoad(?*Fiber, &future_fiber.awaiter, .acquire) == Fiber.finished)
|
|
return i;
|
|
}
|
|
|
|
el.yield(null, .{ .register_select = futures });
|
|
|
|
std.log.debug("back from select yield", .{});
|
|
|
|
const my_thread: *Thread = .current();
|
|
const my_fiber = my_thread.currentFiber();
|
|
var result: ?usize = null;
|
|
|
|
for (futures, 0..) |any_future, i| {
|
|
const future_fiber: *Fiber = @ptrCast(@alignCast(any_future));
|
|
if (@cmpxchgStrong(?*Fiber, &future_fiber.awaiter, my_fiber, null, .seq_cst, .seq_cst)) |awaiter| {
|
|
if (awaiter == Fiber.finished) {
|
|
if (result == null) result = i;
|
|
} else if (awaiter) |a| {
|
|
const closure: *AsyncClosure = .fromFiber(a);
|
|
closure.already_awaited = false;
|
|
}
|
|
} else {
|
|
const closure: *AsyncClosure = .fromFiber(my_fiber);
|
|
closure.already_awaited = false;
|
|
}
|
|
}
|
|
|
|
return result.?;
|
|
}
|
|
|
|
fn cancel(
|
|
userdata: ?*anyopaque,
|
|
any_future: *std.Io.AnyFuture,
|
|
result: []u8,
|
|
result_alignment: Alignment,
|
|
) void {
|
|
const future_fiber: *Fiber = @ptrCast(@alignCast(any_future));
|
|
if (@atomicRmw(
|
|
?*Thread,
|
|
&future_fiber.cancel_thread,
|
|
.Xchg,
|
|
Thread.canceling,
|
|
.acq_rel,
|
|
)) |cancel_thread| if (cancel_thread != Thread.canceling) {
|
|
getSqe(&Thread.current().io_uring).* = .{
|
|
.opcode = .MSG_RING,
|
|
.flags = std.os.linux.IOSQE_CQE_SKIP_SUCCESS,
|
|
.ioprio = 0,
|
|
.fd = cancel_thread.io_uring.fd,
|
|
.off = @intFromPtr(future_fiber),
|
|
.addr = 0,
|
|
.len = @bitCast(-@as(i32, @intFromEnum(std.os.linux.E.INTR))),
|
|
.rw_flags = 0,
|
|
.user_data = @intFromEnum(Completion.UserData.cleanup),
|
|
.buf_index = 0,
|
|
.personality = 0,
|
|
.splice_fd_in = 0,
|
|
.addr3 = 0,
|
|
.resv = 0,
|
|
};
|
|
};
|
|
await(userdata, any_future, result, result_alignment);
|
|
}
|
|
|
|
fn cancelRequested(userdata: ?*anyopaque) bool {
|
|
_ = userdata;
|
|
return @atomicLoad(?*Thread, &Thread.current().currentFiber().cancel_thread, .acquire) == Thread.canceling;
|
|
}
|
|
|
|
fn createFile(
|
|
userdata: ?*anyopaque,
|
|
dir: Io.Dir,
|
|
sub_path: []const u8,
|
|
flags: Io.File.CreateFlags,
|
|
) Io.File.OpenError!Io.File {
|
|
const el: *EventLoop = @ptrCast(@alignCast(userdata));
|
|
const thread: *Thread = .current();
|
|
const iou = &thread.io_uring;
|
|
const fiber = thread.currentFiber();
|
|
try fiber.enterCancelRegion(thread);
|
|
|
|
const posix = std.posix;
|
|
const sub_path_c = try posix.toPosixPath(sub_path);
|
|
|
|
var os_flags: posix.O = .{
|
|
.ACCMODE = if (flags.read) .RDWR else .WRONLY,
|
|
.CREAT = true,
|
|
.TRUNC = flags.truncate,
|
|
.EXCL = flags.exclusive,
|
|
};
|
|
if (@hasField(posix.O, "LARGEFILE")) os_flags.LARGEFILE = true;
|
|
if (@hasField(posix.O, "CLOEXEC")) os_flags.CLOEXEC = true;
|
|
|
|
// Use the O locking flags if the os supports them to acquire the lock
|
|
// atomically. Note that the NONBLOCK flag is removed after the openat()
|
|
// call is successful.
|
|
const has_flock_open_flags = @hasField(posix.O, "EXLOCK");
|
|
if (has_flock_open_flags) switch (flags.lock) {
|
|
.none => {},
|
|
.shared => {
|
|
os_flags.SHLOCK = true;
|
|
os_flags.NONBLOCK = flags.lock_nonblocking;
|
|
},
|
|
.exclusive => {
|
|
os_flags.EXLOCK = true;
|
|
os_flags.NONBLOCK = flags.lock_nonblocking;
|
|
},
|
|
};
|
|
const have_flock = @TypeOf(posix.system.flock) != void;
|
|
|
|
if (have_flock and !has_flock_open_flags and flags.lock != .none) {
|
|
@panic("TODO");
|
|
}
|
|
|
|
if (has_flock_open_flags and flags.lock_nonblocking) {
|
|
@panic("TODO");
|
|
}
|
|
|
|
getSqe(iou).* = .{
|
|
.opcode = .OPENAT,
|
|
.flags = 0,
|
|
.ioprio = 0,
|
|
.fd = dir.handle,
|
|
.off = 0,
|
|
.addr = @intFromPtr(&sub_path_c),
|
|
.len = @intCast(flags.mode),
|
|
.rw_flags = @bitCast(os_flags),
|
|
.user_data = @intFromPtr(fiber),
|
|
.buf_index = 0,
|
|
.personality = 0,
|
|
.splice_fd_in = 0,
|
|
.addr3 = 0,
|
|
.resv = 0,
|
|
};
|
|
|
|
el.yield(null, .nothing);
|
|
fiber.exitCancelRegion(thread);
|
|
|
|
const completion = fiber.resultPointer(Completion);
|
|
switch (errno(completion.result)) {
|
|
.SUCCESS => return .{ .handle = completion.result },
|
|
.INTR => unreachable,
|
|
.CANCELED => return error.Canceled,
|
|
|
|
.FAULT => unreachable,
|
|
.INVAL => return error.BadPathName,
|
|
.BADF => unreachable,
|
|
.ACCES => return error.AccessDenied,
|
|
.FBIG => return error.FileTooBig,
|
|
.OVERFLOW => return error.FileTooBig,
|
|
.ISDIR => return error.IsDir,
|
|
.LOOP => return error.SymLinkLoop,
|
|
.MFILE => return error.ProcessFdQuotaExceeded,
|
|
.NAMETOOLONG => return error.NameTooLong,
|
|
.NFILE => return error.SystemFdQuotaExceeded,
|
|
.NODEV => return error.NoDevice,
|
|
.NOENT => return error.FileNotFound,
|
|
.NOMEM => return error.SystemResources,
|
|
.NOSPC => return error.NoSpaceLeft,
|
|
.NOTDIR => return error.NotDir,
|
|
.PERM => return error.PermissionDenied,
|
|
.EXIST => return error.PathAlreadyExists,
|
|
.BUSY => return error.DeviceBusy,
|
|
.OPNOTSUPP => return error.FileLocksNotSupported,
|
|
.AGAIN => return error.WouldBlock,
|
|
.TXTBSY => return error.FileBusy,
|
|
.NXIO => return error.NoDevice,
|
|
else => |err| return posix.unexpectedErrno(err),
|
|
}
|
|
}
|
|
|
|
fn fileOpen(
|
|
userdata: ?*anyopaque,
|
|
dir: Io.Dir,
|
|
sub_path: []const u8,
|
|
flags: Io.File.OpenFlags,
|
|
) Io.File.OpenError!Io.File {
|
|
const el: *EventLoop = @ptrCast(@alignCast(userdata));
|
|
const thread: *Thread = .current();
|
|
const iou = &thread.io_uring;
|
|
const fiber = thread.currentFiber();
|
|
try fiber.enterCancelRegion(thread);
|
|
|
|
const posix = std.posix;
|
|
const sub_path_c = try posix.toPosixPath(sub_path);
|
|
|
|
var os_flags: posix.O = .{
|
|
.ACCMODE = switch (flags.mode) {
|
|
.read_only => .RDONLY,
|
|
.write_only => .WRONLY,
|
|
.read_write => .RDWR,
|
|
},
|
|
};
|
|
|
|
if (@hasField(posix.O, "CLOEXEC")) os_flags.CLOEXEC = true;
|
|
if (@hasField(posix.O, "LARGEFILE")) os_flags.LARGEFILE = true;
|
|
if (@hasField(posix.O, "NOCTTY")) os_flags.NOCTTY = !flags.allow_ctty;
|
|
|
|
// Use the O locking flags if the os supports them to acquire the lock
|
|
// atomically.
|
|
const has_flock_open_flags = @hasField(posix.O, "EXLOCK");
|
|
if (has_flock_open_flags) {
|
|
// Note that the NONBLOCK flag is removed after the openat() call
|
|
// is successful.
|
|
switch (flags.lock) {
|
|
.none => {},
|
|
.shared => {
|
|
os_flags.SHLOCK = true;
|
|
os_flags.NONBLOCK = flags.lock_nonblocking;
|
|
},
|
|
.exclusive => {
|
|
os_flags.EXLOCK = true;
|
|
os_flags.NONBLOCK = flags.lock_nonblocking;
|
|
},
|
|
}
|
|
}
|
|
const have_flock = @TypeOf(posix.system.flock) != void;
|
|
|
|
if (have_flock and !has_flock_open_flags and flags.lock != .none) {
|
|
@panic("TODO");
|
|
}
|
|
|
|
if (has_flock_open_flags and flags.lock_nonblocking) {
|
|
@panic("TODO");
|
|
}
|
|
|
|
getSqe(iou).* = .{
|
|
.opcode = .OPENAT,
|
|
.flags = 0,
|
|
.ioprio = 0,
|
|
.fd = dir.handle,
|
|
.off = 0,
|
|
.addr = @intFromPtr(&sub_path_c),
|
|
.len = 0,
|
|
.rw_flags = @bitCast(os_flags),
|
|
.user_data = @intFromPtr(fiber),
|
|
.buf_index = 0,
|
|
.personality = 0,
|
|
.splice_fd_in = 0,
|
|
.addr3 = 0,
|
|
.resv = 0,
|
|
};
|
|
|
|
el.yield(null, .nothing);
|
|
fiber.exitCancelRegion(thread);
|
|
|
|
const completion = fiber.resultPointer(Completion);
|
|
switch (errno(completion.result)) {
|
|
.SUCCESS => return .{ .handle = completion.result },
|
|
.INTR => unreachable,
|
|
.CANCELED => return error.Canceled,
|
|
|
|
.FAULT => unreachable,
|
|
.INVAL => return error.BadPathName,
|
|
.BADF => unreachable,
|
|
.ACCES => return error.AccessDenied,
|
|
.FBIG => return error.FileTooBig,
|
|
.OVERFLOW => return error.FileTooBig,
|
|
.ISDIR => return error.IsDir,
|
|
.LOOP => return error.SymLinkLoop,
|
|
.MFILE => return error.ProcessFdQuotaExceeded,
|
|
.NAMETOOLONG => return error.NameTooLong,
|
|
.NFILE => return error.SystemFdQuotaExceeded,
|
|
.NODEV => return error.NoDevice,
|
|
.NOENT => return error.FileNotFound,
|
|
.NOMEM => return error.SystemResources,
|
|
.NOSPC => return error.NoSpaceLeft,
|
|
.NOTDIR => return error.NotDir,
|
|
.PERM => return error.PermissionDenied,
|
|
.EXIST => return error.PathAlreadyExists,
|
|
.BUSY => return error.DeviceBusy,
|
|
.OPNOTSUPP => return error.FileLocksNotSupported,
|
|
.AGAIN => return error.WouldBlock,
|
|
.TXTBSY => return error.FileBusy,
|
|
.NXIO => return error.NoDevice,
|
|
else => |err| return posix.unexpectedErrno(err),
|
|
}
|
|
}
|
|
|
|
fn fileClose(userdata: ?*anyopaque, file: Io.File) void {
|
|
const el: *EventLoop = @ptrCast(@alignCast(userdata));
|
|
const thread: *Thread = .current();
|
|
const iou = &thread.io_uring;
|
|
const fiber = thread.currentFiber();
|
|
|
|
getSqe(iou).* = .{
|
|
.opcode = .CLOSE,
|
|
.flags = 0,
|
|
.ioprio = 0,
|
|
.fd = file.handle,
|
|
.off = 0,
|
|
.addr = 0,
|
|
.len = 0,
|
|
.rw_flags = 0,
|
|
.user_data = @intFromPtr(fiber),
|
|
.buf_index = 0,
|
|
.personality = 0,
|
|
.splice_fd_in = 0,
|
|
.addr3 = 0,
|
|
.resv = 0,
|
|
};
|
|
|
|
el.yield(null, .nothing);
|
|
|
|
const completion = fiber.resultPointer(Completion);
|
|
switch (errno(completion.result)) {
|
|
.SUCCESS => return,
|
|
.INTR => unreachable,
|
|
.CANCELED => return,
|
|
|
|
.BADF => unreachable, // Always a race condition.
|
|
else => return,
|
|
}
|
|
}
|
|
|
|
fn pread(userdata: ?*anyopaque, file: Io.File, buffer: []u8, offset: std.posix.off_t) Io.File.PReadError!usize {
|
|
const el: *EventLoop = @ptrCast(@alignCast(userdata));
|
|
const thread: *Thread = .current();
|
|
const iou = &thread.io_uring;
|
|
const fiber = thread.currentFiber();
|
|
try fiber.enterCancelRegion(thread);
|
|
|
|
getSqe(iou).* = .{
|
|
.opcode = .READ,
|
|
.flags = 0,
|
|
.ioprio = 0,
|
|
.fd = file.handle,
|
|
.off = @bitCast(offset),
|
|
.addr = @intFromPtr(buffer.ptr),
|
|
.len = @min(buffer.len, 0x7ffff000),
|
|
.rw_flags = 0,
|
|
.user_data = @intFromPtr(fiber),
|
|
.buf_index = 0,
|
|
.personality = 0,
|
|
.splice_fd_in = 0,
|
|
.addr3 = 0,
|
|
.resv = 0,
|
|
};
|
|
|
|
el.yield(null, .nothing);
|
|
fiber.exitCancelRegion(thread);
|
|
|
|
const completion = fiber.resultPointer(Completion);
|
|
switch (errno(completion.result)) {
|
|
.SUCCESS => return @as(u32, @bitCast(completion.result)),
|
|
.INTR => unreachable,
|
|
.CANCELED => return error.Canceled,
|
|
|
|
.INVAL => unreachable,
|
|
.FAULT => unreachable,
|
|
.NOENT => return error.ProcessNotFound,
|
|
.AGAIN => return error.WouldBlock,
|
|
.BADF => return error.NotOpenForReading, // Can be a race condition.
|
|
.IO => return error.InputOutput,
|
|
.ISDIR => return error.IsDir,
|
|
.NOBUFS => return error.SystemResources,
|
|
.NOMEM => return error.SystemResources,
|
|
.NOTCONN => return error.SocketUnconnected,
|
|
.CONNRESET => return error.ConnectionResetByPeer,
|
|
.TIMEDOUT => return error.ConnectionTimedOut,
|
|
.NXIO => return error.Unseekable,
|
|
.SPIPE => return error.Unseekable,
|
|
.OVERFLOW => return error.Unseekable,
|
|
else => |err| return std.posix.unexpectedErrno(err),
|
|
}
|
|
}
|
|
|
|
fn pwrite(userdata: ?*anyopaque, file: Io.File, buffer: []const u8, offset: std.posix.off_t) Io.File.PWriteError!usize {
|
|
const el: *EventLoop = @ptrCast(@alignCast(userdata));
|
|
const thread: *Thread = .current();
|
|
const iou = &thread.io_uring;
|
|
const fiber = thread.currentFiber();
|
|
try fiber.enterCancelRegion(thread);
|
|
|
|
getSqe(iou).* = .{
|
|
.opcode = .WRITE,
|
|
.flags = 0,
|
|
.ioprio = 0,
|
|
.fd = file.handle,
|
|
.off = @bitCast(offset),
|
|
.addr = @intFromPtr(buffer.ptr),
|
|
.len = @min(buffer.len, 0x7ffff000),
|
|
.rw_flags = 0,
|
|
.user_data = @intFromPtr(fiber),
|
|
.buf_index = 0,
|
|
.personality = 0,
|
|
.splice_fd_in = 0,
|
|
.addr3 = 0,
|
|
.resv = 0,
|
|
};
|
|
|
|
el.yield(null, .nothing);
|
|
fiber.exitCancelRegion(thread);
|
|
|
|
const completion = fiber.resultPointer(Completion);
|
|
switch (errno(completion.result)) {
|
|
.SUCCESS => return @as(u32, @bitCast(completion.result)),
|
|
.INTR => unreachable,
|
|
.CANCELED => return error.Canceled,
|
|
|
|
.INVAL => return error.InvalidArgument,
|
|
.FAULT => unreachable,
|
|
.NOENT => return error.ProcessNotFound,
|
|
.AGAIN => return error.WouldBlock,
|
|
.BADF => return error.NotOpenForWriting, // can be a race condition.
|
|
.DESTADDRREQ => unreachable, // `connect` was never called.
|
|
.DQUOT => return error.DiskQuota,
|
|
.FBIG => return error.FileTooBig,
|
|
.IO => return error.InputOutput,
|
|
.NOSPC => return error.NoSpaceLeft,
|
|
.ACCES => return error.AccessDenied,
|
|
.PERM => return error.PermissionDenied,
|
|
.PIPE => return error.BrokenPipe,
|
|
.NXIO => return error.Unseekable,
|
|
.SPIPE => return error.Unseekable,
|
|
.OVERFLOW => return error.Unseekable,
|
|
.BUSY => return error.DeviceBusy,
|
|
.CONNRESET => return error.ConnectionResetByPeer,
|
|
.MSGSIZE => return error.MessageTooBig,
|
|
else => |err| return std.posix.unexpectedErrno(err),
|
|
}
|
|
}
|
|
|
|
fn now(userdata: ?*anyopaque, clockid: std.posix.clockid_t) Io.ClockGetTimeError!Io.Timestamp {
|
|
_ = userdata;
|
|
const timespec = try std.posix.clock_gettime(clockid);
|
|
return @enumFromInt(@as(i128, timespec.sec) * std.time.ns_per_s + timespec.nsec);
|
|
}
|
|
|
|
fn sleep(userdata: ?*anyopaque, clockid: std.posix.clockid_t, deadline: Io.Deadline) Io.SleepError!void {
|
|
const el: *EventLoop = @ptrCast(@alignCast(userdata));
|
|
const thread: *Thread = .current();
|
|
const iou = &thread.io_uring;
|
|
const fiber = thread.currentFiber();
|
|
try fiber.enterCancelRegion(thread);
|
|
|
|
const deadline_nanoseconds: i96 = switch (deadline) {
|
|
.duration => |duration| duration.nanoseconds,
|
|
.timestamp => |timestamp| @intFromEnum(timestamp),
|
|
};
|
|
const timespec: std.os.linux.kernel_timespec = .{
|
|
.sec = @intCast(@divFloor(deadline_nanoseconds, std.time.ns_per_s)),
|
|
.nsec = @intCast(@mod(deadline_nanoseconds, std.time.ns_per_s)),
|
|
};
|
|
getSqe(iou).* = .{
|
|
.opcode = .TIMEOUT,
|
|
.flags = 0,
|
|
.ioprio = 0,
|
|
.fd = 0,
|
|
.off = 0,
|
|
.addr = @intFromPtr(×pec),
|
|
.len = 1,
|
|
.rw_flags = @as(u32, switch (deadline) {
|
|
.duration => 0,
|
|
.timestamp => std.os.linux.IORING_TIMEOUT_ABS,
|
|
}) | @as(u32, switch (clockid) {
|
|
.REALTIME => std.os.linux.IORING_TIMEOUT_REALTIME,
|
|
.MONOTONIC => 0,
|
|
.BOOTTIME => std.os.linux.IORING_TIMEOUT_BOOTTIME,
|
|
else => return error.UnsupportedClock,
|
|
}),
|
|
.user_data = @intFromPtr(fiber),
|
|
.buf_index = 0,
|
|
.personality = 0,
|
|
.splice_fd_in = 0,
|
|
.addr3 = 0,
|
|
.resv = 0,
|
|
};
|
|
|
|
el.yield(null, .nothing);
|
|
fiber.exitCancelRegion(thread);
|
|
|
|
const completion = fiber.resultPointer(Completion);
|
|
switch (errno(completion.result)) {
|
|
.SUCCESS, .TIME => return,
|
|
.INTR => unreachable,
|
|
.CANCELED => return error.Canceled,
|
|
|
|
else => |err| return std.posix.unexpectedErrno(err),
|
|
}
|
|
}
|
|
|
|
fn mutexLock(userdata: ?*anyopaque, prev_state: Io.Mutex.State, mutex: *Io.Mutex) error{Canceled}!void {
|
|
const el: *EventLoop = @ptrCast(@alignCast(userdata));
|
|
el.yield(null, .{ .mutex_lock = .{ .prev_state = prev_state, .mutex = mutex } });
|
|
}
|
|
fn mutexUnlock(userdata: ?*anyopaque, prev_state: Io.Mutex.State, mutex: *Io.Mutex) void {
|
|
var maybe_waiting_fiber: ?*Fiber = @ptrFromInt(@intFromEnum(prev_state));
|
|
while (if (maybe_waiting_fiber) |waiting_fiber| @cmpxchgWeak(
|
|
Io.Mutex.State,
|
|
&mutex.state,
|
|
@enumFromInt(@intFromPtr(waiting_fiber)),
|
|
@enumFromInt(@intFromPtr(waiting_fiber.queue_next)),
|
|
.release,
|
|
.acquire,
|
|
) else @cmpxchgWeak(
|
|
Io.Mutex.State,
|
|
&mutex.state,
|
|
.locked_once,
|
|
.unlocked,
|
|
.release,
|
|
.acquire,
|
|
) orelse return) |next_state| maybe_waiting_fiber = @ptrFromInt(@intFromEnum(next_state));
|
|
maybe_waiting_fiber.?.queue_next = null;
|
|
const el: *EventLoop = @ptrCast(@alignCast(userdata));
|
|
el.yield(maybe_waiting_fiber.?, .reschedule);
|
|
}
|
|
|
|
const ConditionImpl = struct {
|
|
tail: *Fiber,
|
|
event: union(enum) {
|
|
queued,
|
|
wake: Io.Condition.Wake,
|
|
},
|
|
};
|
|
|
|
fn conditionWait(userdata: ?*anyopaque, cond: *Io.Condition, mutex: *Io.Mutex) Io.Cancelable!void {
|
|
const el: *EventLoop = @ptrCast(@alignCast(userdata));
|
|
el.yield(null, .{ .condition_wait = .{ .cond = cond, .mutex = mutex } });
|
|
const thread = Thread.current();
|
|
const fiber = thread.currentFiber();
|
|
const cond_impl = fiber.resultPointer(ConditionImpl);
|
|
try mutex.lock(el.io());
|
|
switch (cond_impl.event) {
|
|
.queued => {},
|
|
.wake => |wake| if (fiber.queue_next) |next_fiber| switch (wake) {
|
|
.one => if (@cmpxchgStrong(
|
|
?*Fiber,
|
|
@as(*?*Fiber, @ptrCast(&cond.state)),
|
|
null,
|
|
next_fiber,
|
|
.release,
|
|
.acquire,
|
|
)) |old_fiber| {
|
|
const old_cond_impl = old_fiber.?.resultPointer(ConditionImpl);
|
|
assert(old_cond_impl.tail.queue_next == null);
|
|
old_cond_impl.tail.queue_next = next_fiber;
|
|
old_cond_impl.tail = cond_impl.tail;
|
|
},
|
|
.all => el.schedule(thread, .{ .head = next_fiber, .tail = cond_impl.tail }),
|
|
},
|
|
}
|
|
fiber.queue_next = null;
|
|
}
|
|
|
|
fn conditionWake(userdata: ?*anyopaque, cond: *Io.Condition, wake: Io.Condition.Wake) void {
|
|
const el: *EventLoop = @ptrCast(@alignCast(userdata));
|
|
const waiting_fiber = @atomicRmw(?*Fiber, @as(*?*Fiber, @ptrCast(&cond.state)), .Xchg, null, .acquire) orelse return;
|
|
waiting_fiber.resultPointer(ConditionImpl).event = .{ .wake = wake };
|
|
el.yield(waiting_fiber, .reschedule);
|
|
}
|
|
|
|
fn errno(signed: i32) std.os.linux.E {
|
|
return .init(@bitCast(@as(isize, signed)));
|
|
}
|
|
|
|
fn getSqe(iou: *IoUring) *std.os.linux.io_uring_sqe {
|
|
while (true) return iou.get_sqe() catch {
|
|
_ = iou.submit_and_wait(0) catch |err| switch (err) {
|
|
error.SignalInterrupt => std.log.warn("submit_and_wait failed with SignalInterrupt", .{}),
|
|
else => |e| @panic(@errorName(e)),
|
|
};
|
|
continue;
|
|
};
|
|
}
|