Remove redundant pubsub list to store the patterns. (#8472)

Remove redundant pubsub list to store the patterns.

src/cluster.c

@@ -2126,7 +2126,7 @@ int clusterProcessPacket(clusterLink *link) {
         /* Don't bother creating useless objects if there are no
          * Pub/Sub subscribers. */
         if (dictSize(server.pubsub_channels) ||
-           listLength(server.pubsub_patterns))
+           dictSize(server.pubsub_patterns))
         {
             channel_len = ntohl(hdr->data.publish.msg.channel_len);
             message_len = ntohl(hdr->data.publish.msg.message_len);

src/dict.c

@@ -301,7 +301,7 @@ int dictAdd(dict *d, void *key, void *val)
 /* Low level add or find:
  * This function adds the entry but instead of setting a value returns the
  * dictEntry structure to the user, that will make sure to fill the value
- * field as he wishes.
+ * field as they wish.
  *
  * This function is also directly exposed to the user API to be called
  * mainly in order to store non-pointers inside the hash value, example:

src/pubsub.c

@@ -124,20 +124,6 @@ void addReplyPubsubPatUnsubscribed(client *c, robj *pattern) {
  * Pubsub low level API
  *----------------------------------------------------------------------------*/
 
-void freePubsubPattern(void *p) {
-    pubsubPattern *pat = p;
-
-    decrRefCount(pat->pattern);
-    zfree(pat);
-}
-
-int listMatchPubsubPattern(void *a, void *b) {
-    pubsubPattern *pa = a, *pb = b;
-
-    return (pa->client == pb->client) &&
-           (equalStringObjects(pa->pattern,pb->pattern));
-}
-
 /* Return the number of channels + patterns a client is subscribed to. */
 int clientSubscriptionsCount(client *c) {
     return dictSize(c->pubsub_channels)+
@@ -212,18 +198,13 @@ int pubsubSubscribePattern(client *c, robj *pattern) {
 
     if (listSearchKey(c->pubsub_patterns,pattern) == NULL) {
         retval = 1;
-        pubsubPattern *pat;
         listAddNodeTail(c->pubsub_patterns,pattern);
         incrRefCount(pattern);
-        pat = zmalloc(sizeof(*pat));
-        pat->pattern = getDecodedObject(pattern);
-        pat->client = c;
-        listAddNodeTail(server.pubsub_patterns,pat);
         /* Add the client to the pattern -> list of clients hash table */
-        de = dictFind(server.pubsub_patterns_dict,pattern);
+        de = dictFind(server.pubsub_patterns,pattern);
         if (de == NULL) {
             clients = listCreate();
-            dictAdd(server.pubsub_patterns_dict,pattern,clients);
+            dictAdd(server.pubsub_patterns,pattern,clients);
             incrRefCount(pattern);
         } else {
             clients = dictGetVal(de);
@@ -241,19 +222,14 @@ int pubsubUnsubscribePattern(client *c, robj *pattern, int notify) {
     dictEntry *de;
     list *clients;
     listNode *ln;
-    pubsubPattern pat;
     int retval = 0;
 
     incrRefCount(pattern); /* Protect the object. May be the same we remove */
     if ((ln = listSearchKey(c->pubsub_patterns,pattern)) != NULL) {
         retval = 1;
         listDelNode(c->pubsub_patterns,ln);
-        pat.client = c;
-        pat.pattern = pattern;
-        ln = listSearchKey(server.pubsub_patterns,&pat);
-        listDelNode(server.pubsub_patterns,ln);
         /* Remove the client from the pattern -> clients list hash table */
-        de = dictFind(server.pubsub_patterns_dict,pattern);
+        de = dictFind(server.pubsub_patterns,pattern);
         serverAssertWithInfo(c,NULL,de != NULL);
         clients = dictGetVal(de);
         ln = listSearchKey(clients,c);
@@ -262,7 +238,7 @@ int pubsubUnsubscribePattern(client *c, robj *pattern, int notify) {
         if (listLength(clients) == 0) {
             /* Free the list and associated hash entry at all if this was
              * the latest client. */
-            dictDelete(server.pubsub_patterns_dict,pattern);
+            dictDelete(server.pubsub_patterns,pattern);
         }
     }
     /* Notify the client */
@@ -329,7 +305,7 @@ int pubsubPublishMessage(robj *channel, robj *message) {
         }
     }
     /* Send to clients listening to matching channels */
-    di = dictGetIterator(server.pubsub_patterns_dict);
+    di = dictGetIterator(server.pubsub_patterns);
     if (di) {
         channel = getDecodedObject(channel);
         while((de = dictNext(di)) != NULL) {
@@ -502,7 +478,7 @@ NULL
         }
     } else if (!strcasecmp(c->argv[1]->ptr,"numpat") && c->argc == 2) {
         /* PUBSUB NUMPAT */
-        addReplyLongLong(c,listLength(server.pubsub_patterns));
+        addReplyLongLong(c,dictSize(server.pubsub_patterns));
     } else {
         addReplySubcommandSyntaxError(c);
     }

src/server.c

@@ -3206,10 +3206,7 @@ void initServer(void) {
     }
     evictionPoolAlloc(); /* Initialize the LRU keys pool. */
     server.pubsub_channels = dictCreate(&keylistDictType,NULL);
-    server.pubsub_patterns = listCreate();
+    server.pubsub_patterns = dictCreate(&keylistDictType,NULL);
-    server.pubsub_patterns_dict = dictCreate(&keylistDictType,NULL);
-    listSetFreeMethod(server.pubsub_patterns,freePubsubPattern);
-    listSetMatchMethod(server.pubsub_patterns,listMatchPubsubPattern);
     server.cronloops = 0;
     server.in_eval = 0;
     server.in_exec = 0;
@@ -4959,7 +4956,7 @@ sds genRedisInfoString(const char *section) {
             server.stat_keyspace_hits,
             server.stat_keyspace_misses,
             dictSize(server.pubsub_channels),
-            listLength(server.pubsub_patterns),
+            dictSize(server.pubsub_patterns),
             server.stat_fork_time,
             server.stat_total_forks,
             dictSize(server.migrate_cached_sockets),

src/server.h

@@ -1521,8 +1521,7 @@ struct redisServer {
     long long blocked_last_cron; /* Indicate the mstime of the last time we did cron jobs from a blocking operation */
     /* Pubsub */
     dict *pubsub_channels;  /* Map channels to list of subscribed clients */
-    list *pubsub_patterns;  /* A list of pubsub_patterns */
+    dict *pubsub_patterns;  /* A dict of pubsub_patterns */
-    dict *pubsub_patterns_dict;  /* A dict of pubsub_patterns */
     int notify_keyspace_events; /* Events to propagate via Pub/Sub. This is an
                                    xor of NOTIFY_... flags. */
     /* Cluster */
@@ -1609,11 +1608,6 @@ struct redisServer {
     int failover_state; /* Failover state */
 };
 
-typedef struct pubsubPattern {
-    client *client;
-    robj *pattern;
-} pubsubPattern;
-
 #define MAX_KEYS_BUFFER 256
 
 /* A result structure for the various getkeys function calls. It lists the
@@ -2280,8 +2274,6 @@ int hashZiplistValidateIntegrity(unsigned char *zl, size_t size, int deep);
 /* Pub / Sub */
 int pubsubUnsubscribeAllChannels(client *c, int notify);
 int pubsubUnsubscribeAllPatterns(client *c, int notify);
-void freePubsubPattern(void *p);
-int listMatchPubsubPattern(void *a, void *b);
 int pubsubPublishMessage(robj *channel, robj *message);
 void addReplyPubsubMessage(client *c, robj *channel, robj *msg);