@@ -766,7 +766,6 @@ int dlg_new_dialog(sip_msg_t *req, struct cell *t, const int run_initial_cbs)

     str ttag;

     str req_uri;

     unsigned int dir;

-    int mlock;

 	dlg = dlg_get_ctx_dialog();

     if(dlg != NULL) {

@@ -792,14 +791,10 @@ int dlg_new_dialog(sip_msg_t *req, struct cell *t, const int run_initial_cbs)

     trim(&req_uri);

 	dir = DLG_DIR_NONE;

-	mlock = 1;

 	/* search dialog by SIP attributes

-	 * - if not found, hash table slot is left locked, to avoid races

-	 *   to add 'same' dialog on parallel forking or not-handled-yet

-	 *   retransmissions. Release slot after linking new dialog */

-	dlg = search_dlg(&callid, &ftag, &ttag, &dir);

+	 * - hash table slot is left locked  */

+	dlg = dlg_search(&callid, &ftag, &ttag, &dir);

 	if(dlg) {

-		mlock = 0;

 		if (detect_spirals) {

 			if (spiral_detected == 1)

 				return 0;

@@ -817,13 +812,11 @@ int dlg_new_dialog(sip_msg_t *req, struct cell *t, const int run_initial_cbs)

 				_dlg_ctx.iuid.h_id = dlg->h_id;

 				/* search_dlg() has incremented the ref count by 1 */

 				dlg_release(dlg);

+				dlg_hash_release(&callid);

 				return 0;

 			}

 			dlg_release(dlg);

 		}

-		/* lock the slot - dlg found, but in dlg_state_deleted, do a new one */

-		dlg_hash_lock(&callid);

-		mlock = 1;

     }

     spiral_detected = 0;

@@ -834,7 +827,7 @@ int dlg_new_dialog(sip_msg_t *req, struct cell *t, const int run_initial_cbs)

                          &req_uri /*r-uri*/ );

 	if (dlg==0) {

-		if(likely(mlock==1)) dlg_hash_release(&callid);

+		dlg_hash_release(&callid);

 		LM_ERR("failed to create new dialog\n");

 		return -1;

 	}

@@ -842,7 +835,7 @@ int dlg_new_dialog(sip_msg_t *req, struct cell *t, const int run_initial_cbs)

 	/* save caller's tag, cseq, contact and record route*/

 	if (populate_leg_info(dlg, req, t, DLG_CALLER_LEG,

 			&(get_from(req)->tag_value)) !=0) {

-		if(likely(mlock==1)) dlg_hash_release(&callid);

+		dlg_hash_release(&callid);

 		LM_ERR("could not add further info to the dialog\n");

 		shm_free(dlg);

 		return -1;

@@ -851,9 +844,10 @@ int dlg_new_dialog(sip_msg_t *req, struct cell *t, const int run_initial_cbs)

 	/* Populate initial varlist: */

 	dlg->vars = get_local_varlist_pointer(req, 1);

-	/* if search_dlg() returned NULL, slot was kept locked */

-	link_dlg(dlg, 0, mlock);

-	if(likely(mlock==1)) dlg_hash_release(&callid);

+	/* after dlg_search() slot was kept locked */

+	link_dlg(dlg, 0, 0);

+	/* unlock after dlg_search() */

+	dlg_hash_release(&callid);

 	dlg->lifetime = get_dlg_timeout(req);

 	s.s   = _dlg_ctx.to_route_name;

@@ -738,7 +738,7 @@ static inline struct dlg_cell* internal_get_dlg(unsigned int h_entry,

 		/* Check callid / fromtag / totag */

 		if (match_dialog( dlg, callid, ftag, ttag, dir)==1) {

 			ref_dlg_unsafe(dlg, 1);

-			dlg_unlock( d_table, d_entry);

+			if(likely(mode==0)) dlg_unlock( d_table, d_entry);

 			LM_DBG("dialog callid='%.*s' found on entry %u, dir=%d\n",

 				callid->len, callid->s,h_entry,*dir);

 			return dlg;

@@ -794,15 +794,15 @@ struct dlg_cell* get_dlg( str *callid, str *ftag, str *ttag, unsigned int *dir)

  * referred to as a dialog."

  * Note that the caller is responsible for decrementing (or reusing)

  * the reference counter by one again if a dialog has been found.

- * If the dialog is not found, the hash slot is left locked, to allow

- * linking the structure of a new dialog.

+ * Important: the hash slot is left locked (e.g., needed to allow

+ * linking the structure of a new dialog).

  * \param callid callid

  * \param ftag from tag

  * \param ttag to tag

  * \param dir direction

  * \return dialog structure on success, NULL on failure (and slot locked)

  */

-dlg_cell_t* search_dlg( str *callid, str *ftag, str *ttag, unsigned int *dir)

+dlg_cell_t* dlg_search( str *callid, str *ftag, str *ttag, unsigned int *dir)

 {

 	struct dlg_cell *dlg;

 	unsigned int he;

@@ -345,15 +345,15 @@ dlg_cell_t* get_dlg(str *callid, str *ftag, str *ttag, unsigned int *dir);

  * referred to as a dialog."

  * Note that the caller is responsible for decrementing (or reusing)

  * the reference counter by one again if a dialog has been found.

- * If the dialog is not found, the hash slot is left locked, to allow

- * linking the structure of a new dialog.

+ * Important: the hash slot is left locked (e.g., needed to allow

+ * linking the structure of a new dialog).

  * \param callid callid

  * \param ftag from tag

  * \param ttag to tag

  * \param dir direction

  * \return dialog structure on success, NULL on failure (and slot locked)

  */

-dlg_cell_t* search_dlg(str *callid, str *ftag, str *ttag, unsigned int *dir);

+dlg_cell_t* dlg_search(str *callid, str *ftag, str *ttag, unsigned int *dir);

 /*!