Implement test mode to make finding bugs easier

Former-commit-id: 971f69fe1ff9cce50492a47f306b312457e50b9f

src/config.cpp

@@ -864,6 +864,8 @@ void loadServerConfigFromString(char *config) {
         } else if (!strcasecmp(argv[0], "version-override") && argc == 2) {
             KEYDB_SET_VERSION = zstrdup(argv[1]);
             serverLog(LL_WARNING, "Warning version is overriden to: %s\n", KEYDB_SET_VERSION);
+        } else if (!strcasecmp(argv[0],"testmode") && argc == 2){
+            g_fTestMode = yesnotoi(argv[1]);
         } else {
             err = "Bad directive or wrong number of arguments"; goto loaderr;
         }

src/networking.cpp

@@ -1097,11 +1097,31 @@ void acceptTcpHandler(aeEventLoop *el, int fd, void *privdata, int mask) {
         serverLog(LL_VERBOSE,"Accepted %s:%d", cip, cport);
         int ielCur = ielFromEventLoop(el);
 
+        if (!g_fTestMode)
+        {
             // We always accept on the same thread
+        LLocalThread:
             aeAcquireLock();
             acceptCommonHandler(cfd,0,cip, ielCur);
             aeReleaseLock();
         }
+        else
+        {
+            // In test mode we want a good distribution among threads and avoid the main thread
+            //  since the main thread is most likely to work
+            int iel = IDX_EVENT_LOOP_MAIN;
+            while (cserver.cthreads > 1 && iel == IDX_EVENT_LOOP_MAIN)
+                iel = rand() % cserver.cthreads;
+            if (iel == ielFromEventLoop(el))
+                goto LLocalThread;
+            char *szT = (char*)zmalloc(NET_IP_STR_LEN, MALLOC_LOCAL);
+            memcpy(szT, cip, NET_IP_STR_LEN);
+            aePostFunction(g_pserver->rgthreadvar[iel].el, [cfd, iel, szT]{
+                acceptCommonHandler(cfd,0,szT, iel);
+                zfree(szT);
+            });
+        }
+    }
 }
 
 void acceptUnixHandler(aeEventLoop *el, int fd, void *privdata, int mask) {

src/server.cpp

@@ -61,6 +61,8 @@
 #include <uuid/uuid.h>
 #include "aelocker.h"
 
+int g_fTestMode = false;
+
 /* Our shared "common" objects */
 
 struct sharedObjectsStruct shared;

src/server.h

@@ -88,6 +88,8 @@ typedef long long mstime_t; /* millisecond time type. */
 #include "endianconv.h"
 #include "crc64.h"
 
+extern int g_fTestMode;
+
 struct redisObject;
 class robj_roptr
 {