From 0aed6a952a0acf5a02ec4b588031ec3dc231a68c Mon Sep 17 00:00:00 2001
From: antirez <antirez@gmail.com>
Date: Thu, 10 Mar 2011 16:39:19 +0100
Subject: [PATCH] fixed diskstore race condition

---
 src/dscache.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/dscache.c b/src/dscache.c
index 2dbc1134..cbe9bb01 100644
--- a/src/dscache.c
+++ b/src/dscache.c
@@ -890,8 +890,16 @@ int waitForSwappedKey(redisClient *c, robj *key) {
     listAddNodeTail(l,c);
 
     /* Are we already loading the key from disk? If not create a job */
-    if (de == NULL)
-        cacheScheduleIO(c->db,key,REDIS_IO_LOAD);
+    if (de == NULL) {
+        int flags = cacheScheduleIOGetFlags(c->db,key);
+
+        /* It is possible that even if there are no clients waiting for
+         * a load operation, still we have a load operation in progress.
+         * For instance think to a client performing a GET and then
+         * closing the connection */
+        if ((flags & (REDIS_IO_LOAD|REDIS_IO_LOADINPROG)) == 0)
+            cacheScheduleIO(c->db,key,REDIS_IO_LOAD);
+    }
     return 1;
 }
 
-- 
2.47.2