From 39be6a0ac9ffaa5ddf93f092b63b34c8ee6934b9 Mon Sep 17 00:00:00 2001
From: Ricky Zhang <ricky.zhang@sas.com>
Date: Thu, 18 Sep 2014 16:10:41 -0400
Subject: [PATCH] Use atomic operation

---
 .../src/Unix/Linux/NetDriver/sheep_net.c      | 24 ++++++++++---------
 1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/BasiliskII/src/Unix/Linux/NetDriver/sheep_net.c b/BasiliskII/src/Unix/Linux/NetDriver/sheep_net.c
index 5b36170f..2e3ead5e 100644
--- a/BasiliskII/src/Unix/Linux/NetDriver/sheep_net.c
+++ b/BasiliskII/src/Unix/Linux/NetDriver/sheep_net.c
@@ -158,7 +158,7 @@ struct SheepVars {
 	char eth_addr[6];			/* Hardware address of the Ethernet card */
 	char fake_addr[6];			/* Local faked hardware address (what SheepShaver sees) */
 #ifdef LINUX_3_15
-    int got_packet;
+    atomic_t got_packet;
 #endif
 };
 
@@ -396,14 +396,10 @@ static ssize_t sheep_net_read(struct file *f, char *buf, size_t count, loff_t *o
 		if (skb != NULL || (f->f_flags & O_NONBLOCK))
 			break;
 
-        /*packet is not available*/
-        #ifdef LINUX_3_15
-        v->got_packet = 0;
-        #endif
-
 		/* No packet in queue and in blocking mode, so block */
         #ifdef LINUX_3_15
-        wait_event_interruptible(v->wait, v->got_packet == 1);
+        atomic_set(&v->got_packet, 0);
+        wait_event_interruptible(v->wait, atomic_read(&v->got_packet));
         #else
         interruptible_sleep_on(&v->wait);
         #endif
@@ -746,12 +742,18 @@ static int sheep_net_receiver(struct sk_buff *skb, struct net_device *dev, struc
 	/* Enqueue packet */
 	skb_queue_tail(&v->queue, skb);
 
+    /* Unblock blocked read */
     #ifdef LINUX_3_15
-    v->got_packet = 1;
-    #endif
 
-	/* Unblock blocked read */
-	wake_up(&v->wait);
+    atomic_set(&v->got_packet, 1);
+
+    wake_up_interruptible(&v->wait);
+
+    #else
+
+    wake_up(&v->wait);
+
+    #endif
 	return 0;
 
 drop: