Function start [src]

Create a new child progress node. Thread-safe. Passing 0 for estimated_total_items means unknown.

Prototype

pub fn start(node: Node, name: []const u8, estimated_total_items: usize) Node

Parameters

node: Nodename: []const u8estimated_total_items: usize

Source

  pub fn start(node: Node, name: []const u8, estimated_total_items: usize) Node {
    if (noop_impl) {
        assert(node.index == .none);
        return Node.none;
    }
    const node_index = node.index.unwrap() orelse return Node.none;
    const parent = node_index.toParent();

    const freelist_head = &global_progress.node_freelist_first;
    var opt_free_index = @atomicLoad(Node.OptionalIndex, freelist_head, .seq_cst);
    while (opt_free_index.unwrap()) |free_index| {
        const freelist_ptr = freelistByIndex(free_index);
        const next = @atomicLoad(Node.OptionalIndex, freelist_ptr, .seq_cst);
        opt_free_index = @cmpxchgWeak(Node.OptionalIndex, freelist_head, opt_free_index, next, .seq_cst, .seq_cst) orelse {
            // We won the allocation race.
            return init(free_index, parent, name, estimated_total_items);
        };
    }

    const free_index = @atomicRmw(u32, &global_progress.node_end_index, .Add, 1, .monotonic);
    if (free_index >= global_progress.node_storage.len) {
        // Ran out of node storage memory. Progress for this node will not be tracked.
        _ = @atomicRmw(u32, &global_progress.node_end_index, .Sub, 1, .monotonic);
        return Node.none;
    }

    return init(@enumFromInt(free_index), parent, name, estimated_total_items);
}  