new preloading implemented, still EXEC not handled correctly, everything to test

src/db.c

@@ -616,3 +616,75 @@ void persistCommand(redisClient *c) {
         }
     }
 }
+
+/* -----------------------------------------------------------------------------
+ * API to get key arguments from commands
+ * ---------------------------------------------------------------------------*/
+
+int *getKeysUsingCommandTable(struct redisCommand *cmd,robj **argv, int argc, int *numkeys) {
+    int j, i = 0, last, *keys;
+    REDIS_NOTUSED(argv);
+
+    if (cmd->firstkey == 0) {
+        *numkeys = 0;
+        return NULL;
+    }
+    last = cmd->lastkey;
+    if (last < 0) last = argc+last;
+    keys = zmalloc(sizeof(int)*((last - cmd->firstkey)+1));
+    for (j = cmd->firstkey; j <= last; j += cmd->keystep) {
+        redisAssert(j < argc);
+        keys[i] = j;
+    }
+    return keys;
+}
+
+int *getKeysFromCommand(struct redisCommand *cmd,robj **argv, int argc, int *numkeys, int flags) {
+    if (cmd->getkeys_proc) {
+        return cmd->getkeys_proc(cmd,argv,argc,numkeys,flags);
+    } else {
+        return getKeysUsingCommandTable(cmd,argv,argc,numkeys);
+    }
+}
+
+void getKeysFreeResult(int *result) {
+    zfree(result);
+}
+
+int *noPreloadGetKeys(struct redisCommand *cmd,robj **argv, int argc, int *numkeys, int flags) {
+    if (flags & REDIS_GETKEYS_PRELOAD) {
+        *numkeys = 0;
+        return NULL;
+    } else {
+        return getKeysUsingCommandTable(cmd,argv,argc,numkeys);
+    }
+}
+
+int *renameGetKeys(struct redisCommand *cmd,robj **argv, int argc, int *numkeys, int flags) {
+    if (flags & REDIS_GETKEYS_PRELOAD) {
+        int *keys = zmalloc(sizeof(int));
+        *numkeys = 1;
+        keys[0] = 1;
+        return NULL;
+    } else {
+        return getKeysUsingCommandTable(cmd,argv,argc,numkeys);
+    }
+}
+
+int *zunionInterGetKeys(struct redisCommand *cmd,robj **argv, int argc, int *numkeys, int flags) {
+    int i, num, *keys;
+    REDIS_NOTUSED(cmd);
+    REDIS_NOTUSED(flags);
+
+    num = atoi(argv[2]->ptr);
+    /* Sanity check. Don't return any key if the command is going to
+     * reply with syntax error. */
+    if (num > (argc-3)) {
+        *numkeys = 0;
+        return NULL;
+    }
+    keys = zmalloc(num);
+    for (i = 0; i < num; i++) keys[i] = 3+i;
+    *numkeys = num;
+    return keys;
+}

src/dscache.c

@@ -903,6 +903,7 @@ int waitForSwappedKey(redisClient *c, robj *key) {
     return 1;
 }
 
+#if 0
 /* Preload keys for any command with first, last and step values for
  * the command keys prototype, as defined in the command table. */
 void waitForMultipleSwappedKeys(redisClient *c, struct redisCommand *cmd, int argc, robj **argv) {
@@ -955,6 +956,7 @@ void execBlockClientOnSwappedKeys(redisClient *c, struct redisCommand *cmd, int
         }
     }
 }
+#endif
 
 /* Is this client attempting to run a command against swapped keys?
  * If so, block it ASAP, load the keys in background, then resume it.
@@ -967,11 +969,13 @@ void execBlockClientOnSwappedKeys(redisClient *c, struct redisCommand *cmd, int
  * Return 1 if the client is marked as blocked, 0 if the client can
  * continue as the keys it is going to access appear to be in memory. */
 int blockClientOnSwappedKeys(redisClient *c, struct redisCommand *cmd) {
-    if (cmd->vm_preload_proc != NULL) {
-        cmd->vm_preload_proc(c,cmd,c->argc,c->argv);
-    } else {
-        waitForMultipleSwappedKeys(c,cmd,c->argc,c->argv);
-    }
+    int *keyindex, numkeys, j;
+
+    keyindex = getKeysFromCommand(cmd,c->argv,c->argc,&numkeys,REDIS_GETKEYS_PRELOAD);
+    for (j = 0; j < numkeys; j++) waitForSwappedKey(c,c->argv[keyindex[j]]);
+    getKeysFreeResult(keyindex);
+
+#warning "Handle EXEC here"
 
     /* If the client was blocked for at least one key, mark it as blocked. */
     if (listLength(c->io_keys)) {

src/redis.c

@@ -168,7 +168,7 @@ struct redisCommand redisCommandTable[] = {
     {"lastsave",lastsaveCommand,1,0,NULL,0,0,0,0,0},
     {"type",typeCommand,2,0,NULL,1,1,1,0,0},
     {"multi",multiCommand,1,0,NULL,0,0,0,0,0},
-    {"exec",execCommand,1,REDIS_CMD_DENYOOM,execGetKeys,0,0,0,0,0},
+    {"exec",execCommand,1,REDIS_CMD_DENYOOM,NULL,0,0,0,0,0},
     {"discard",discardCommand,1,0,NULL,0,0,0,0,0},
     {"sync",syncCommand,1,0,NULL,0,0,0,0,0},
     {"flushdb",flushdbCommand,1,0,NULL,0,0,0,0,0},

src/redis.h

@@ -507,20 +507,19 @@ typedef struct pubsubPattern {
 } pubsubPattern;
 
 typedef void redisCommandProc(redisClient *c);
-typedef void redisVmPreloadProc(redisClient *c, struct redisCommand *cmd, int argc, robj **argv);
+typedef int *redisGetKeysProc(struct redisCommand *cmd, robj **argv, int argc, int *numkeys, int flags);
 struct redisCommand {
     char *name;
     redisCommandProc *proc;
     int arity;
     int flags;
-    /* Use a function to determine which keys need to be loaded
-     * in the background prior to executing this command. Takes precedence
-     * over vm_firstkey and others, ignored when NULL */
-    redisVmPreloadProc *vm_preload_proc;
+    /* Use a function to determine keys arguments in a command line.
+     * Used both for diskstore preloading and Redis Cluster. */
+    redisGetKeysProc *getkeys_proc;
     /* What keys should be loaded in background when calling this command? */
-    int vm_firstkey; /* The first argument that's a key (0 = no keys) */
-    int vm_lastkey;  /* THe last argument that's a key */
-    int vm_keystep;  /* The step between first and last key */
+    int firstkey; /* The first argument that's a key (0 = no keys) */
+    int lastkey;  /* THe last argument that's a key */
+    int keystep;  /* The step between first and last key */
     long long microseconds, calls;
 };
 
@@ -829,8 +828,6 @@ void freeIOJob(iojob *j);
 void queueIOJob(iojob *j);
 void waitEmptyIOJobsQueue(void);
 void processAllPendingIOJobs(void);
-void zunionInterBlockClientOnSwappedKeys(redisClient *c, struct redisCommand *cmd, int argc, robj **argv);
-void execBlockClientOnSwappedKeys(redisClient *c, struct redisCommand *cmd, int argc, robj **argv);
 int blockClientOnSwappedKeys(redisClient *c, struct redisCommand *cmd);
 int dontWaitForSwappedKey(redisClient *c, robj *key);
 void handleClientsBlockedOnSwappedKey(redisDb *db, robj *key);
@@ -917,6 +914,15 @@ int selectDb(redisClient *c, int id);
 void signalModifiedKey(redisDb *db, robj *key);
 void signalFlushedDb(int dbid);
 
+/* API to get key arguments from commands */
+#define REDIS_GETKEYS_ALL 0
+#define REDIS_GETKEYS_PRELOAD 1
+int *getKeysFromCommand(struct redisCommand *cmd, robj **argv, int argc, int *numkeys, int flags);
+void getKeysFreeResult(int *result);
+int *noPreloadGetKeys(struct redisCommand *cmd,robj **argv, int argc, int *numkeys, int flags);
+int *renameGetKeys(struct redisCommand *cmd,robj **argv, int argc, int *numkeys, int flags);
+int *zunionInterGetKeys(struct redisCommand *cmd,robj **argv, int argc, int *numkeys, int flags);
+
 /* Git SHA1 */
 char *redisGitSHA1(void);
 char *redisGitDirty(void);