From 55ccc812e6ec7f639391be8239fb5de9a47b25a0 Mon Sep 17 00:00:00 2001
From: Stephen Marz <stephen.marz@utk.edu>
Date: Mon, 18 May 2020 09:11:41 -0400
Subject: [PATCH] Add comments.

---
 risc_v/src/sched.rs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/risc_v/src/sched.rs b/risc_v/src/sched.rs
index 685a754..272ea8c 100755
--- a/risc_v/src/sched.rs
+++ b/risc_v/src/sched.rs
@@ -9,6 +9,9 @@ use crate::cpu::get_mtime;
 pub fn schedule() -> usize {
 	let mut frame_addr: usize = 0x1111;
 	unsafe {
+		// If we can't get the lock, then usually this means a kernel
+		// process has the lock. So, we return 0. This has a special
+		// meaning to whomever calls the scheduler to say "nobody else got scheduled"
 		if PROCESS_LIST_MUTEX.try_lock() == false {
 			return 0;
 		}