node: add local_time and increment it by a fixed amount any time a task runs

src/io_interface.zig

@@ -4,25 +4,25 @@ const Node = @import("node.zig");
 const Io = std.Io;
 const net = Io.net;
 
-const Dir               = Io.Dir;
+const Dir = Io.Dir;
-const File              = Io.File;
+const File = Io.File;
-const Group             = Io.Group;
+const Group = Io.Group;
-const AnyFuture         = Io.AnyFuture;
+const AnyFuture = Io.AnyFuture;
-const ConcurrentError   = Io.ConcurrentError;
+const ConcurrentError = Io.ConcurrentError;
-const CancelProtection  = Io.CancelProtection;
+const CancelProtection = Io.CancelProtection;
-const Cancelable        = Io.Cancelable;
+const Cancelable = Io.Cancelable;
-const Timeout           = Io.Timeout;
+const Timeout = Io.Timeout;
-const Operation         = Io.Operation;
+const Operation = Io.Operation;
-const Batch             = Io.Batch;
+const Batch = Io.Batch;
-const Terminal          = Io.Terminal;
+const Terminal = Io.Terminal;
-const LockedStderr      = Io.LockedStderr;
+const LockedStderr = Io.LockedStderr;
-const Clock             = Io.Clock;
+const Clock = Io.Clock;
-const Timestamp         = Io.Timestamp;
+const Timestamp = Io.Timestamp;
-const Duration          = Io.Duration;
+const Duration = Io.Duration;
 const RandomSecureError = Io.RandomSecureError;
-const Queue             = Io.Queue;
+const Queue = Io.Queue;
-const Allocator         = std.mem.Allocator;
+const Allocator = std.mem.Allocator;
-const TaskID            = Node.TaskID;
+const TaskID = Node.TaskID;
 
 pub fn buildIOInterfaceForNode(node: *Node) Io {
     return .{
@@ -499,16 +499,16 @@ fn dirCreateDir(userdata: ?*anyopaque, dir: Dir, sub_path: []const u8, permissio
 
     node.createDir(parent, sub_path) catch |e| {
         return switch (e) {
-            Node.CreateDirError.InvalidHandle          => unreachable,
+            Node.CreateDirError.InvalidHandle => unreachable,
-            Node.CreateDirError.ExistsAlready          => Dir.CreateDirError.PathAlreadyExists,
+            Node.CreateDirError.ExistsAlready => Dir.CreateDirError.PathAlreadyExists,
-            Node.CreateDirError.EmptyPath              => Dir.CreateDirError.BadPathName,
+            Node.CreateDirError.EmptyPath => Dir.CreateDirError.BadPathName,
-            Node.CreateDirError.NoRootParent           => Dir.CreateDirError.FileNotFound,
+            Node.CreateDirError.NoRootParent => Dir.CreateDirError.FileNotFound,
-            Node.CreateDirError.TooManyComponents      => Dir.CreateDirError.NameTooLong,
+            Node.CreateDirError.TooManyComponents => Dir.CreateDirError.NameTooLong,
-            Node.CreateDirError.ResolutionLimit        => Dir.CreateDirError.NameTooLong,
+            Node.CreateDirError.ResolutionLimit => Dir.CreateDirError.NameTooLong,
-            Node.CreateDirError.ComponentNotDirectory  => Dir.CreateDirError.NotDir,
+            Node.CreateDirError.ComponentNotDirectory => Dir.CreateDirError.NotDir,
-            Node.CreateDirError.ComponentNotFound      => Dir.CreateDirError.FileNotFound,
+            Node.CreateDirError.ComponentNotFound => Dir.CreateDirError.FileNotFound,
-            Node.CreateDirError.OutOfMemory            => Dir.CreateDirError.SystemResources,
+            Node.CreateDirError.OutOfMemory => Dir.CreateDirError.SystemResources,
-            Node.CreateDirError.Canceled               => return error.Canceled,
+            Node.CreateDirError.Canceled => return error.Canceled,
         };
     };
 }
@@ -538,17 +538,17 @@ fn dirOpenDir(userdata: ?*anyopaque, dir: Dir, sub_path: []const u8, options: Di
 
     const handle = node.openDir(parent, sub_path) catch |e| {
         return switch (e) {
-            Node.OpenDirError.InvalidHandle            => unreachable,
+            Node.OpenDirError.InvalidHandle => unreachable,
-            Node.OpenDirError.DescriptorLimit          => Dir.OpenError.ProcessFdQuotaExceeded,
+            Node.OpenDirError.DescriptorLimit => Dir.OpenError.ProcessFdQuotaExceeded,
-            Node.OpenDirError.IsDirectory              => unreachable,
+            Node.OpenDirError.IsDirectory => unreachable,
-            Node.OpenDirError.NotDirectory             => Dir.OpenError.NotDir,
+            Node.OpenDirError.NotDirectory => Dir.OpenError.NotDir,
-            Node.OpenDirError.EmptyPath                => Dir.OpenError.BadPathName,
+            Node.OpenDirError.EmptyPath => Dir.OpenError.BadPathName,
-            Node.OpenDirError.NoRootParent             => Dir.OpenError.FileNotFound,
+            Node.OpenDirError.NoRootParent => Dir.OpenError.FileNotFound,
-            Node.OpenDirError.TooManyComponents        => Dir.OpenError.NameTooLong,
+            Node.OpenDirError.TooManyComponents => Dir.OpenError.NameTooLong,
-            Node.OpenDirError.ResolutionLimit          => Dir.OpenError.NameTooLong,
+            Node.OpenDirError.ResolutionLimit => Dir.OpenError.NameTooLong,
-            Node.OpenDirError.ComponentNotDirectory    => Dir.OpenError.NotDir,
+            Node.OpenDirError.ComponentNotDirectory => Dir.OpenError.NotDir,
-            Node.OpenDirError.ComponentNotFound        => Dir.OpenError.FileNotFound,
+            Node.OpenDirError.ComponentNotFound => Dir.OpenError.FileNotFound,
-            Node.OpenDirError.Canceled                 => return error.Canceled,
+            Node.OpenDirError.Canceled => return error.Canceled,
         };
     };
 
@@ -585,32 +585,32 @@ fn dirCreateFile(userdata: ?*anyopaque, dir: Dir, sub_path: []const u8, flags: D
 
     node.createFile(parent, sub_path) catch |e| {
         return switch (e) {
-            Node.CreateFileError.InvalidHandle          => unreachable,
+            Node.CreateFileError.InvalidHandle => unreachable,
-            Node.CreateFileError.ExistsAlready          => File.OpenError.PathAlreadyExists,
+            Node.CreateFileError.ExistsAlready => File.OpenError.PathAlreadyExists,
-            Node.CreateFileError.EmptyPath              => File.OpenError.BadPathName,
+            Node.CreateFileError.EmptyPath => File.OpenError.BadPathName,
-            Node.CreateFileError.NoRootParent           => File.OpenError.FileNotFound,
+            Node.CreateFileError.NoRootParent => File.OpenError.FileNotFound,
-            Node.CreateFileError.TooManyComponents      => File.OpenError.NameTooLong,
+            Node.CreateFileError.TooManyComponents => File.OpenError.NameTooLong,
-            Node.CreateFileError.ResolutionLimit        => File.OpenError.NameTooLong,
+            Node.CreateFileError.ResolutionLimit => File.OpenError.NameTooLong,
-            Node.CreateFileError.ComponentNotDirectory  => File.OpenError.NotDir,
+            Node.CreateFileError.ComponentNotDirectory => File.OpenError.NotDir,
-            Node.CreateFileError.ComponentNotFound      => File.OpenError.FileNotFound,
+            Node.CreateFileError.ComponentNotFound => File.OpenError.FileNotFound,
-            Node.CreateFileError.OutOfMemory            => File.OpenError.SystemResources,
+            Node.CreateFileError.OutOfMemory => File.OpenError.SystemResources,
-            Node.CreateFileError.Canceled               => return error.Canceled,
+            Node.CreateFileError.Canceled => return error.Canceled,
         };
     };
 
     const handle = node.openFile(parent, sub_path) catch |e| {
         return switch (e) {
-            Node.OpenFileError.InvalidHandle            => unreachable,
+            Node.OpenFileError.InvalidHandle => unreachable,
-            Node.OpenFileError.DescriptorLimit          => File.OpenError.ProcessFdQuotaExceeded,
+            Node.OpenFileError.DescriptorLimit => File.OpenError.ProcessFdQuotaExceeded,
-            Node.OpenFileError.IsDirectory              => File.OpenError.IsDir,
+            Node.OpenFileError.IsDirectory => File.OpenError.IsDir,
-            Node.OpenFileError.NotDirectory             => File.OpenError.NotDir,
+            Node.OpenFileError.NotDirectory => File.OpenError.NotDir,
-            Node.OpenFileError.EmptyPath                => File.OpenError.BadPathName,
+            Node.OpenFileError.EmptyPath => File.OpenError.BadPathName,
-            Node.OpenFileError.NoRootParent             => File.OpenError.FileNotFound,
+            Node.OpenFileError.NoRootParent => File.OpenError.FileNotFound,
-            Node.OpenFileError.TooManyComponents        => File.OpenError.NameTooLong,
+            Node.OpenFileError.TooManyComponents => File.OpenError.NameTooLong,
-            Node.OpenFileError.ResolutionLimit          => File.OpenError.NameTooLong,
+            Node.OpenFileError.ResolutionLimit => File.OpenError.NameTooLong,
-            Node.OpenFileError.ComponentNotDirectory    => File.OpenError.NotDir,
+            Node.OpenFileError.ComponentNotDirectory => File.OpenError.NotDir,
-            Node.OpenFileError.ComponentNotFound        => File.OpenError.FileNotFound,
+            Node.OpenFileError.ComponentNotFound => File.OpenError.FileNotFound,
-            Node.OpenFileError.Canceled                 => return error.Canceled,
+            Node.OpenFileError.Canceled => return error.Canceled,
         };
     };
 
@@ -636,17 +636,17 @@ fn dirOpenFile(userdata: ?*anyopaque, dir: Dir, sub_path: []const u8, flags: Dir
 
     const handle = node.openFile(parent, sub_path) catch |e| {
         return switch (e) {
-            Node.OpenFileError.InvalidHandle            => unreachable,
+            Node.OpenFileError.InvalidHandle => unreachable,
-            Node.OpenFileError.DescriptorLimit          => File.OpenError.ProcessFdQuotaExceeded,
+            Node.OpenFileError.DescriptorLimit => File.OpenError.ProcessFdQuotaExceeded,
-            Node.OpenFileError.IsDirectory              => File.OpenError.IsDir,
+            Node.OpenFileError.IsDirectory => File.OpenError.IsDir,
-            Node.OpenFileError.NotDirectory             => File.OpenError.NotDir,
+            Node.OpenFileError.NotDirectory => File.OpenError.NotDir,
-            Node.OpenFileError.EmptyPath                => File.OpenError.BadPathName,
+            Node.OpenFileError.EmptyPath => File.OpenError.BadPathName,
-            Node.OpenFileError.NoRootParent             => File.OpenError.FileNotFound,
+            Node.OpenFileError.NoRootParent => File.OpenError.FileNotFound,
-            Node.OpenFileError.TooManyComponents        => File.OpenError.NameTooLong,
+            Node.OpenFileError.TooManyComponents => File.OpenError.NameTooLong,
-            Node.OpenFileError.ResolutionLimit          => File.OpenError.NameTooLong,
+            Node.OpenFileError.ResolutionLimit => File.OpenError.NameTooLong,
-            Node.OpenFileError.ComponentNotDirectory    => File.OpenError.NotDir,
+            Node.OpenFileError.ComponentNotDirectory => File.OpenError.NotDir,
-            Node.OpenFileError.ComponentNotFound        => File.OpenError.FileNotFound,
+            Node.OpenFileError.ComponentNotFound => File.OpenError.FileNotFound,
-            Node.OpenFileError.Canceled                 => return error.Canceled,
+            Node.OpenFileError.Canceled => return error.Canceled,
         };
     };
 
@@ -745,17 +745,17 @@ fn dirDeleteDir(userdata: ?*anyopaque, dir: Dir, sub_path: []const u8) Dir.Delet
 
     node.deleteDir(parent, sub_path) catch |e| {
         return switch (e) {
-            Node.DeleteDirError.InvalidHandle          => unreachable,
+            Node.DeleteDirError.InvalidHandle => unreachable,
-            Node.DeleteDirError.EmptyPath              => Dir.DeleteDirError.BadPathName,
+            Node.DeleteDirError.EmptyPath => Dir.DeleteDirError.BadPathName,
-            Node.DeleteDirError.NoRootParent           => Dir.DeleteDirError.FileNotFound,
+            Node.DeleteDirError.NoRootParent => Dir.DeleteDirError.FileNotFound,
-            Node.DeleteDirError.TooManyComponents      => Dir.DeleteDirError.NameTooLong,
+            Node.DeleteDirError.TooManyComponents => Dir.DeleteDirError.NameTooLong,
-            Node.DeleteDirError.ResolutionLimit        => Dir.DeleteDirError.NameTooLong,
+            Node.DeleteDirError.ResolutionLimit => Dir.DeleteDirError.NameTooLong,
-            Node.DeleteDirError.ComponentNotDirectory  => Dir.DeleteDirError.NotDir,
+            Node.DeleteDirError.ComponentNotDirectory => Dir.DeleteDirError.NotDir,
-            Node.DeleteDirError.ComponentNotFound      => Dir.DeleteDirError.FileNotFound,
+            Node.DeleteDirError.ComponentNotFound => Dir.DeleteDirError.FileNotFound,
-            Node.DeleteDirError.NotFound               => Dir.DeleteDirError.FileNotFound,
+            Node.DeleteDirError.NotFound => Dir.DeleteDirError.FileNotFound,
-            Node.DeleteDirError.NotDirectory           => Dir.DeleteDirError.NotDir,
+            Node.DeleteDirError.NotDirectory => Dir.DeleteDirError.NotDir,
-            Node.DeleteDirError.DirNotEmpty            => Dir.DeleteDirError.DirNotEmpty,
+            Node.DeleteDirError.DirNotEmpty => Dir.DeleteDirError.DirNotEmpty,
-            Node.DeleteDirError.Canceled               => return error.Canceled,
+            Node.DeleteDirError.Canceled => return error.Canceled,
         };
     };
 }
@@ -868,14 +868,7 @@ fn fileClose(userdata: ?*anyopaque, files: []const File) void {
     }
 }
 
-fn fileWritePositional(
+fn fileWritePositional(userdata: ?*anyopaque, file: File, header: []const u8, data: []const []const u8, splat: usize, offset: u64) File.WritePositionalError!usize {
-    userdata: ?*anyopaque,
-    file    : File,
-    header  : []const u8,
-    data    : []const []const u8,
-    splat   : usize,
-    offset  : u64
-) File.WritePositionalError!usize {
     const node: *Node = @ptrCast(@alignCast(userdata.?));
     var cursor = std.math.cast(usize, offset) orelse return File.WritePositionalError.FileTooBig;
     var copied: usize = 0;
@@ -1201,7 +1194,7 @@ fn now(userdata: ?*anyopaque, clock: Clock) Timestamp {
     // TODO: Return an appropriate time for each clock
     _ = clock;
 
-    return .{ .nanoseconds = node.scheduler.current_time * 1000 };
+    return .{ .nanoseconds = node.local_time * 1000 };
 }
 
 fn clockResolution(userdata: ?*anyopaque, clock: Clock) Clock.ResolutionError!Duration {

src/node.zig

@@ -1,12 +1,12 @@
 const std = @import("std");
 const Allocator = std.mem.Allocator;
 
-const FileSystem  = @import("file_system.zig");
+const FileSystem = @import("file_system.zig");
-const Network     = @import("network.zig");
+const Network = @import("network.zig");
-const Scheduler   = @import("scheduler.zig");
+const Scheduler = @import("scheduler.zig");
 const ioInterface = @import("io_interface.zig");
 
-const MAX_DESCRIPTORS = 1<<10;
+const MAX_DESCRIPTORS = 1 << 10;
 
 const Node = @This();
 const Handle = i32;
@@ -15,7 +15,6 @@ pub const TaskID = Scheduler.TaskID;
 const NestedEntryPoint = Scheduler.NestedEntryPoint;
 
 const Descriptor = struct {
-
     const Kind = enum {
         dir,
         file,
@@ -24,14 +23,15 @@ const Descriptor = struct {
         unused,
     };
 
-    kind  : Kind = .unused,
+    kind: Kind = .unused,
-    dir   : FileSystem.OpenDir   = undefined,
+    dir: FileSystem.OpenDir = undefined,
-    file  : FileSystem.OpenFile  = undefined,
+    file: FileSystem.OpenFile = undefined,
     listen: Network.ListenSocket = undefined,
-    conn  : Network.ConnSocket   = undefined,
+    conn: Network.ConnSocket = undefined,
 };
 
 gpa: Allocator,
+local_time: u64,
 arena: std.heap.ArenaAllocator,
 argv: [][*:0]const u8,
 environ_map: std.process.Environ.Map,
@@ -52,7 +52,7 @@ fn splitCommandArguments(command: []const u8, arena: Allocator) Allocator.Error!
     // Count how many arguments there are
     var count: usize = 0;
     while (cursor < command.len) {
-        if (command[cursor] != ' ' and (cursor == 0 or command[cursor-1] == ' '))
+        if (command[cursor] != ' ' and (cursor == 0 or command[cursor - 1] == ' '))
             count += 1;
         cursor += 1;
     }
@@ -80,16 +80,9 @@ fn splitCommandArguments(command: []const u8, arena: Allocator) Allocator.Error!
     return result;
 }
 
-pub fn init(
+pub fn init(self: *Node, real_io: std.Io, scheduler: *Scheduler, network: *Network, command: []const u8, addresses: []const u32, gpa: Allocator) !void {
-    self     : *Node,
-    real_io  : std.Io,
-    scheduler: *Scheduler,
-    network  : *Network,
-    command  : []const u8,
-    addresses: []const u32,
-    gpa      : Allocator
-) !void {
     self.gpa = gpa;
+    self.local_time = 0;
     self.arena = .init(gpa);
     self.scheduler = scheduler;
     try self.file_system.init(gpa);
@@ -105,7 +98,7 @@ pub fn init(
     self.environ_map = try std.process.Environ.createMap(.empty, gpa);
 
     self.real_io = real_io;
-    self.stdin_reader  = std.Io.File.stdin().readerStreaming(real_io, &.{});
+    self.stdin_reader = std.Io.File.stdin().readerStreaming(real_io, &.{});
     self.stdout_writer = std.Io.File.stdout().writerStreaming(real_io, &self.stdout_buffer);
     self.stderr_writer = std.Io.File.stderr().writerStreaming(real_io, &self.stderr_buffer);
 }
@@ -183,11 +176,11 @@ fn unusedDesc(self: *Node) ?*Descriptor {
     return null;
 }
 
-const HandleError = error {
+const HandleError = error{
     InvalidHandle,
 };
 
-pub const CancelError = error {
+pub const CancelError = error{
     Canceled,
 };
 
@@ -237,14 +230,10 @@ pub const CreateDirError = HandleError || FileSystem.CreateError || CancelError;
 
 pub fn createDir(self: *Node, parent: ?Handle, path: []const u8) CreateDirError!void {
     try self.scheduler.sleep(10);
-    return self.file_system.createDir(
+    return self.file_system.createDir(path, try self.handleToOpenDirOrNULL(parent), self.gpa);
-        path,
-        try self.handleToOpenDirOrNULL(parent),
-        self.gpa
-    );
 }
 
-pub const OpenDirError = error {
+pub const OpenDirError = error{
     DescriptorLimit,
 } || HandleError || FileSystem.OpenError || CancelError;
 
@@ -285,36 +274,24 @@ pub const CreateFileError = HandleError || FileSystem.CreateError || CancelError
 
 pub fn createFile(self: *Node, parent: ?Handle, path: []const u8) CreateFileError!void {
     try self.scheduler.sleep(10);
-    return self.file_system.createFile(
+    return self.file_system.createFile(path, try self.handleToOpenDirOrNULL(parent), self.gpa);
-        path,
-        try self.handleToOpenDirOrNULL(parent),
-        self.gpa
-    );
 }
 
 pub const DeleteFileError = HandleError || FileSystem.DeleteFileError || CancelError;
 
 pub fn deleteFile(self: *Node, parent: ?Handle, path: []const u8) DeleteFileError!void {
     try self.scheduler.sleep(10);
-    return self.file_system.deleteFile(
+    return self.file_system.deleteFile(path, try self.handleToOpenDirOrNULL(parent), self.gpa);
-        path,
-        try self.handleToOpenDirOrNULL(parent),
-        self.gpa
-    );
 }
 
 pub const DeleteDirError = HandleError || FileSystem.DeleteDirError || CancelError;
 
 pub fn deleteDir(self: *Node, parent: ?Handle, path: []const u8) DeleteDirError!void {
     try self.scheduler.sleep(10);
-    return self.file_system.deleteDir(
+    return self.file_system.deleteDir(path, try self.handleToOpenDirOrNULL(parent), self.gpa);
-        path,
-        try self.handleToOpenDirOrNULL(parent),
-        self.gpa
-    );
 }
 
-pub const OpenFileError = error {
+pub const OpenFileError = error{
     DescriptorLimit,
 } || HandleError || FileSystem.OpenError || CancelError;
 
@@ -383,14 +360,7 @@ fn writeToStderr(self: *Node, source: []const u8) void {
 
 pub const WriteFileError = HandleError || Allocator.Error || CancelError;
 
-pub fn writeFile(
+pub fn writeFile(self: *Node, handle: Handle, offset: ?usize, header: []const u8, source: []const []const u8) WriteFileError!usize {
-    self  : *Node,
-    handle: Handle,
-    offset: ?usize,
-    header: []const u8,
-    source: []const []const u8
-) WriteFileError!usize {
-
     try self.scheduler.sleep(100);
 
     if (handle == 0) {
@@ -441,7 +411,7 @@ pub fn seekFileBy(self: *Node, handle: Handle, offset: i64) SeekFileError!void {
 }
 
 pub const Address = Network.Address;
-pub const ListenError = error {
+pub const ListenError = error{
     DescriptorLimit,
 } || Network.ListenError || CancelError;
 
@@ -453,7 +423,7 @@ pub fn listen(self: *Node, address: Address) ListenError!Handle {
     return self.descToHandle(desc);
 }
 
-pub const AcceptError = error {
+pub const AcceptError = error{
     DescriptorLimit,
 } || HandleError || Network.AcceptError || CancelError;
 
@@ -472,7 +442,7 @@ pub fn accept(self: *Node, handle: Handle) AcceptError!Handle {
     }
 }
 
-pub const ConnectError = error {
+pub const ConnectError = error{
     DescriptorLimit,
 } || Network.ConnectError || CancelError;
 

src/scheduler.zig

@@ -4,8 +4,8 @@ const Node = @import("node.zig");
 
 const Scheduler = @This();
 
-pub const MainEntryPoint = *const fn(std.process.Init) anyerror!void;
+pub const MainEntryPoint = *const fn (std.process.Init) anyerror!void;
-pub const NestedEntryPoint = *const fn(context: *const anyopaque) void;
+pub const NestedEntryPoint = *const fn (context: *const anyopaque) void;
 
 pub const EntryPoint = union(enum) {
     main: MainEntryPoint,
@@ -26,6 +26,7 @@ const ContextSwitch = extern struct {
 
 const STACK_CANARY_SIZE = 256;
 const STACK_CANARY_BYTE = 0xa5;
+const TASK_RUN_COST_US = 50;
 
 pub const TaskID = u64;
 
@@ -38,13 +39,13 @@ const State = enum {
 };
 
 const Task = struct {
-    id    : TaskID,
+    id: TaskID,
-    regs  : Registers,
+    regs: Registers,
-    stack : []align(16) u8,
+    stack: []align(16) u8,
-    entry : EntryPoint,
+    entry: EntryPoint,
     context: ?*const anyopaque,
-    state : State,
+    state: State,
-    node  : *Node,
+    node: *Node,
 
     // If this is a subtask, parent_id refers to the parent.
     // The cancel flag is set when the parent requests cancellation.
@@ -107,7 +108,6 @@ fn spawnInner(
     parent_id: ?TaskID,
     context: ?*const anyopaque,
 ) !*Task {
-
     if (stack_size > std.math.maxInt(usize) - STACK_CANARY_SIZE)
         return Allocator.Error.OutOfMemory;
 
@@ -125,7 +125,7 @@ fn spawnInner(
     const id = self.next_task_id;
     defer self.next_task_id += 1;
 
-    const task = Task {
+    const task = Task{
         .id = id,
         .regs = .{
             .rsp = stack_top,
@@ -133,14 +133,14 @@ fn spawnInner(
             .rip = @intFromPtr(&taskStart),
             .rdi = @intFromPtr(self),
         },
-        .stack  = stack,
+        .stack = stack,
-        .entry  = entry,
+        .entry = entry,
         .context = context,
-        .state  = .ready,
+        .state = .ready,
         .wakeup_time = null,
         .wakeup_tasks = null,
         .wakeup_futex = null,
-        .node   = node,
+        .node = node,
         .parent_id = parent_id,
         .cancel = false,
     };
@@ -196,6 +196,9 @@ fn findBlockedTaskWithLowestWakeupTime(self: *Scheduler) ?*Task {
 fn advanceTimeAndUnblockTasks(self: *Scheduler, new_time: u64) void {
     std.debug.assert(self.current_time < new_time);
     self.current_time = new_time;
+    for (self.tasks.items) |task| {
+        task.node.local_time = @max(task.node.local_time, new_time);
+    }
     for (self.tasks.items) |*task| {
         if (task.state == .blocked) {
             if (task.wakeup_time) |wakeup_time| {
@@ -229,9 +232,7 @@ fn advanceTimeAndPickTask(self: *Scheduler) ?*Task {
 }
 
 pub fn scheduleOne(self: *Scheduler) bool {
-    const task = self.findTaskWithState(.ready)
+    const task = self.findTaskWithState(.ready) orelse self.advanceTimeAndPickTask() orelse return false;
-        orelse self.advanceTimeAndPickTask()
-        orelse return false;
     const id = task.id;
     self.current_id = id;
     task.state = .running;
@@ -258,21 +259,21 @@ fn contextSwitch(old: *Registers, new: *Registers) void {
         :
         : [message] "{rsi}" (&ContextSwitch{ .old = old, .new = new }),
         : .{
-            .rax = true,
+          .rax = true,
-            .rcx = true,
+          .rcx = true,
-            .rdx = true,
+          .rdx = true,
-            .rbx = true,
+          .rbx = true,
-            .rsi = true,
+          .rsi = true,
-            .rdi = true,
+          .rdi = true,
-            .r8 = true,
+          .r8 = true,
-            .r9 = true,
+          .r9 = true,
-            .r10 = true,
+          .r10 = true,
-            .r11 = true,
+          .r11 = true,
-            .r12 = true,
+          .r12 = true,
-            .r13 = true,
+          .r13 = true,
-            .r14 = true,
+          .r14 = true,
-            .r15 = true,
+          .r15 = true,
-            .memory = true,
+          .memory = true,
         });
 }
 
@@ -296,6 +297,7 @@ fn taskStart(self: *Scheduler) callconv(.c) noreturn {
     current.wakeup_time = null;
     current.wakeup_tasks = null;
     current.wakeup_futex = null;
+    current.node.local_time += TASK_RUN_COST_US;
     if (current.parent_id) |parent_id| {
         if (self.findTaskByID(parent_id)) |parent| {
             if (taskIsWaitingFor(parent, current.id)) {
@@ -322,6 +324,7 @@ pub fn sleep(self: *Scheduler, delta_us: u64) !void {
     current.wakeup_time = self.current_time + delta_us;
     current.wakeup_tasks = null;
     current.wakeup_futex = null;
+    current.node.local_time += TASK_RUN_COST_US;
     contextSwitch(&current.regs, &self.regs);
     try self.checkCancel();
 }
@@ -341,6 +344,7 @@ pub fn futexWaitUncancelable(self: *Scheduler, ptr: *const u32, expected: u32) v
     current.wakeup_time = null;
     current.wakeup_tasks = null;
     current.wakeup_futex = ptr;
+    current.node.local_time += TASK_RUN_COST_US;
     contextSwitch(&current.regs, &self.regs);
 }
 
@@ -385,6 +389,7 @@ pub fn wait(self: *Scheduler, ids: []const TaskID) !TaskID {
         task.wakeup_time = null;
         task.wakeup_tasks = ids;
         task.wakeup_futex = null;
+        task.node.local_time += TASK_RUN_COST_US;
         contextSwitch(&task.regs, &self.regs);
         try self.checkCancel();
     }