From a4ce7581553b1f4e29a7ed2141add788e56142c5 Mon Sep 17 00:00:00 2001
From: Pieter Noordhuis <pcnoordhuis@gmail.com>
Date: Mon, 6 Dec 2010 16:39:39 +0100
Subject: [PATCH] Don't execute commands for clients when they are unblocked

---
 src/redis.c  | 19 +++++++++++++++++--
 src/redis.h  |  1 +
 src/t_list.c |  7 +------
 3 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/src/redis.c b/src/redis.c
index 8a5f9632..a1653c36 100644
--- a/src/redis.c
+++ b/src/redis.c
@@ -646,15 +646,16 @@ int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
  * for ready file descriptors. */
 void beforeSleep(struct aeEventLoop *eventLoop) {
     REDIS_NOTUSED(eventLoop);
+    listNode *ln;
+    redisClient *c;
 
     /* Awake clients that got all the swapped keys they requested */
     if (server.vm_enabled && listLength(server.io_ready_clients)) {
         listIter li;
-        listNode *ln;
 
         listRewind(server.io_ready_clients,&li);
         while((ln = listNext(&li))) {
-            redisClient *c = ln->value;
+            c = ln->value;
             struct redisCommand *cmd;
 
             /* Resume the client. */
@@ -672,6 +673,19 @@ void beforeSleep(struct aeEventLoop *eventLoop) {
                 processInputBuffer(c);
         }
     }
+
+    /* Try to process pending commands for clients that were just unblocked. */
+    while (listLength(server.unblocked_clients)) {
+        ln = listFirst(server.unblocked_clients);
+        redisAssert(ln != NULL);
+        c = ln->value;
+        listDelNode(server.unblocked_clients,ln);
+
+        /* Process remaining data in the input buffer. */
+        if (c->querybuf && sdslen(c->querybuf) > 0)
+            processInputBuffer(c);
+    }
+
     /* Write the AOF buffer on disk */
     flushAppendOnlyFile();
 }
@@ -818,6 +832,7 @@ void initServer() {
     server.clients = listCreate();
     server.slaves = listCreate();
     server.monitors = listCreate();
+    server.unblocked_clients = listCreate();
     createSharedObjects();
     server.el = aeCreateEventLoop();
     server.db = zmalloc(sizeof(redisDb)*server.dbnum);
diff --git a/src/redis.h b/src/redis.h
index 27cb8259..3639f062 100644
--- a/src/redis.h
+++ b/src/redis.h
@@ -435,6 +435,7 @@ struct redisServer {
     /* Blocked clients */
     unsigned int bpop_blocked_clients;
     unsigned int vm_blocked_clients;
+    list *unblocked_clients;
     /* Sort parameters - qsort_r() is only available under BSD so we
      * have to take this state global, in order to pass it to sortCompare() */
     int sort_desc;
diff --git a/src/t_list.c b/src/t_list.c
index 867e258a..7dc3f139 100644
--- a/src/t_list.c
+++ b/src/t_list.c
@@ -759,12 +759,7 @@ void unblockClientWaitingData(redisClient *c) {
     c->bpop.target = NULL;
     c->flags &= (~REDIS_BLOCKED);
     server.bpop_blocked_clients--;
-    /* We want to process data if there is some command waiting
-     * in the input buffer. Note that this is safe even if
-     * unblockClientWaitingData() gets called from freeClient() because
-     * freeClient() will be smart enough to call this function
-     * *after* c->querybuf was set to NULL. */
-    if (c->querybuf && sdslen(c->querybuf) > 0) processInputBuffer(c);
+    listAddNodeTail(server.unblocked_clients,c);
 }
 
 /* This should be called from any function PUSHing into lists.
-- 
2.45.2