diff --git a/core/src/sys/sched.zig b/core/src/sys/sched.zig
index e1b9f19..67d5b02 100644
--- a/core/src/sys/sched.zig
+++ b/core/src/sys/sched.zig
@@ -24,15 +24,15 @@ pub fn yield(regs: *platform.Registers, _: *sys.Arguments, _: *isize) anyerror!v
 
 pub fn setPriority(_: *platform.Registers, args: *sys.Arguments, _: *isize) anyerror!void {
     const core = cpu.thisCore();
-
     if (!sys.checkToken(core, system.kernel.Token.ThreadPriority)) return error.NotAuthorized;
+    const target = thread.lookupThreadById(args.arg0) orelse return error.NoSuchThread;
 
-    core.current_thread.user_priority = @truncate(args.arg0);
+    target.user_priority = @truncate(args.arg1);
 }
 
-pub fn getPriority(_: *platform.Registers, _: *sys.Arguments, retval: *isize) anyerror!void {
-    const core = cpu.thisCore();
-    retval.* = core.current_thread.user_priority;
+pub fn getPriority(_: *platform.Registers, args: *sys.Arguments, retval: *isize) anyerror!void {
+    const target = thread.lookupThreadById(args.arg0) orelse return error.NoSuchThread;
+    retval.* = target.user_priority;
 }
 
 pub fn sleep(regs: *platform.Registers, args: *sys.Arguments, _: *isize) anyerror!void {
diff --git a/system/lib/syscalls.zig b/system/lib/syscalls.zig
index be5cf59..e45eb30 100644
--- a/system/lib/syscalls.zig
+++ b/system/lib/syscalls.zig
@@ -36,12 +36,15 @@ pub fn yield() void {
     _ = syscall(.Yield, 0, 0, 0);
 }
 
-pub fn setPriority(priority: u8) void {
-    _ = syscall(.SetPriority, priority, 0, 0);
+pub fn setPriority(pid: u64, priority: u8) !void {
+    const retval = syscall(.SetPriority, pid, priority, 0);
+    if (retval < 0) return error.NoSuchThread;
 }
 
-pub fn getPriority() u8 {
-    return @truncate(@as(u64, @bitCast(syscall(.GetPriority, 0, 0, 0))));
+pub fn getPriority(pid: u64) !u8 {
+    const retval = syscall(.GetPriority, pid, 0, 0);
+    if (retval < 0) return error.NoSuchThread;
+    return @truncate(@as(u64, @bitCast(retval)));
 }
 
 pub fn sleep(ms: u64) void {