runner: pass jobserver to task handler as reference

Some code simplification.

2 files changed, 16 insertions, 18 deletions

diff --git a/crates/runner/src/lib.rs b/crates/runner/src/lib.rs
index 8104daa..ae56981 100644
--- a/crates/runner/src/lib.rs
+++ b/crates/runner/src/lib.rs
@@ -46,11 +46,11 @@ fn handle_sigchld() {
 }
 
 fn handle_request(
-	jobserver: Jobserver,
+	jobserver: &mut Jobserver,
 	socket: UnixSeqpacketConn,
 	request_socket: UnixStream,
-) -> (Jobserver, UnixSeqpacketConn) {
-	let child = |(mut jobserver, socket): (Jobserver, UnixSeqpacketConn)| {
+) -> UnixSeqpacketConn {
+	let child = |socket| {
 		drop(socket);
 
 		let task: Task =
@@ -59,29 +59,30 @@ fn handle_request(
 		prctl::set_name(&task.label).expect("prctl(PR_SET_NAME)");
 
 		let token = jobserver.wait();
-		let (pid, mut jobserver) = unsafe {
-			clone::spawn(None, jobserver, |jobserver| {
+		let pid = unsafe {
+			clone::spawn(None, (), |()| {
 				let result = task::handle(task, jobserver);
 				bincode::serialize_into(&request_socket, &result)
 					.expect("Failed to send task result");
 				drop(request_socket);
 			})
 		}
-		.expect("fork()");
+		.expect("fork()")
+		.0;
 		let wait_res = wait::waitpid(pid, None);
 		jobserver.post(token);
 		wait_res.expect("waitpid()");
 	};
 
-	unsafe { clone::spawn(None, (jobserver, socket), child) }
+	unsafe { clone::spawn(None, socket, child) }
 		.expect("fork()")
 		.1
 }
 
 fn handle_socket(
-	jobserver: Jobserver,
+	jobserver: &mut Jobserver,
 	socket: UnixSeqpacketConn,
-) -> Option<(Jobserver, UnixSeqpacketConn)> {
+) -> Option<UnixSeqpacketConn> {
 	let mut fd = 0;
 
 	match socket
@@ -139,13 +140,10 @@ fn runner(uid: Uid, gid: Gid, mut socket: UnixSeqpacketConn, _lockfile: File, op
 			.revents()
 			.expect("Unknown events in poll() return");
 		if events.contains(poll::PollFlags::POLLIN) {
-			match handle_socket(jobserver, socket) {
-				Some((jobserver_ret, socket_ret)) => {
-					jobserver = jobserver_ret;
-					socket = socket_ret;
-				}
+			socket = match handle_socket(&mut jobserver, socket) {
+				Some(socket) => socket,
 				None => break,
-			}
+			};
 		} else if events.intersects(!poll::PollFlags::POLLIN) {
 			panic!("Unexpected error status for socket file descriptor");
 		}
diff --git a/crates/runner/src/task.rs b/crates/runner/src/task.rs
index ff27399..6c52be2 100644
--- a/crates/runner/src/task.rs
+++ b/crates/runner/src/task.rs
@@ -237,7 +237,7 @@ fn collect_outputs(input_hash: &InputHash, task: &Task) -> Result<HashMap<String
 	Ok(ret)
 }
 
-fn run_task(input_hash: &InputHash, task: &Task, mut jobserver: Jobserver) -> Result<()> {
+fn run_task(input_hash: &InputHash, task: &Task, jobserver: &mut Jobserver) -> Result<()> {
 	let _workdir_mount = init_task(input_hash, task).context("Failed to initialize task")?;
 	unpack_dependencies(input_hash, task).context("Failed to unpack dependencies")?;
 	let _rootfs_mount = init_task_rootfs(input_hash).context("Failed to initialize task rootfs")?;
@@ -392,7 +392,7 @@ fn move_layer(input_hash: &InputHash, hash: &Option<LayerHash>) -> Result<()> {
 fn run_and_hash_task(
 	input_hash: &InputHash,
 	task: &Task,
-	jobserver: Jobserver,
+	jobserver: &mut Jobserver,
 ) -> Result<TaskOutput> {
 	run_task(input_hash, task, jobserver)?;
 
@@ -430,7 +430,7 @@ fn save_cached(input_hash: &InputHash, output: &TaskOutput) -> Result<()> {
 	Ok(())
 }
 
-pub fn handle(task: Task, jobserver: Jobserver) -> Result<TaskOutput> {
+pub fn handle(task: Task, jobserver: &mut Jobserver) -> Result<TaskOutput> {
 	let input_hash = input_hash(&task);
 
 	// TODO: We should not hold a job token while waiting on the lock