diff --git a/src/pattern.c b/src/pattern.c
index e028545..328c514 100644
--- a/src/pattern.c
+++ b/src/pattern.c
@@ -500,7 +500,7 @@
 		unsigned long long seed = pat_lru_seed ^ (long)expr;
 
 		lru = lru64_get(XXH64(smp->data.u.str.area, smp->data.u.str.data, seed),
-				pat_lru_tree, expr, expr->revision);
+				pat_lru_tree, expr, expr->ref->revision);
 		if (lru && lru->domain) {
 			ret = lru->data;
 			return ret;
@@ -523,7 +523,7 @@
 	}
 
 	if (lru)
-		lru64_commit(lru, ret, expr, expr->revision, NULL);
+		lru64_commit(lru, ret, expr, expr->ref->revision, NULL);
 
 	return ret;
 }
@@ -540,7 +540,7 @@
 		unsigned long long seed = pat_lru_seed ^ (long)expr;
 
 		lru = lru64_get(XXH64(smp->data.u.str.area, smp->data.u.str.data, seed),
-				pat_lru_tree, expr, expr->revision);
+				pat_lru_tree, expr, expr->ref->revision);
 		if (lru && lru->domain) {
 			ret = lru->data;
 			return ret;
@@ -560,7 +560,7 @@
 	}
 
 	if (lru)
-		lru64_commit(lru, ret, expr, expr->revision, NULL);
+		lru64_commit(lru, ret, expr, expr->ref->revision, NULL);
 
 	return ret;
 }
@@ -603,7 +603,7 @@
 		unsigned long long seed = pat_lru_seed ^ (long)expr;
 
 		lru = lru64_get(XXH64(smp->data.u.str.area, smp->data.u.str.data, seed),
-				pat_lru_tree, expr, expr->revision);
+				pat_lru_tree, expr, expr->ref->revision);
 		if (lru && lru->domain) {
 			ret = lru->data;
 			return ret;
@@ -620,7 +620,7 @@
 	}
 
 	if (lru)
-		lru64_commit(lru, ret, expr, expr->revision, NULL);
+		lru64_commit(lru, ret, expr, expr->ref->revision, NULL);
 
 	return ret;
 }
@@ -679,7 +679,7 @@
 		unsigned long long seed = pat_lru_seed ^ (long)expr;
 
 		lru = lru64_get(XXH64(smp->data.u.str.area, smp->data.u.str.data, seed),
-				pat_lru_tree, expr, expr->revision);
+				pat_lru_tree, expr, expr->ref->revision);
 		if (lru && lru->domain) {
 			ret = lru->data;
 			return ret;
@@ -702,7 +702,7 @@
 	}
 
 	if (lru)
-		lru64_commit(lru, ret, expr, expr->revision, NULL);
+		lru64_commit(lru, ret, expr, expr->ref->revision, NULL);
 
 	return ret;
 }
@@ -720,7 +720,7 @@
 		unsigned long long seed = pat_lru_seed ^ (long)expr;
 
 		lru = lru64_get(XXH64(smp->data.u.str.area, smp->data.u.str.data, seed),
-				pat_lru_tree, expr, expr->revision);
+				pat_lru_tree, expr, expr->ref->revision);
 		if (lru && lru->domain) {
 			ret = lru->data;
 			return ret;
@@ -743,7 +743,7 @@
 	}
 
 	if (lru)
-		lru64_commit(lru, ret, expr, expr->revision, NULL);
+		lru64_commit(lru, ret, expr, expr->ref->revision, NULL);
 
 	return ret;
 }
@@ -765,7 +765,7 @@
 		unsigned long long seed = pat_lru_seed ^ (long)expr;
 
 		lru = lru64_get(XXH64(smp->data.u.str.area, smp->data.u.str.data, seed),
-				pat_lru_tree, expr, expr->revision);
+				pat_lru_tree, expr, expr->ref->revision);
 		if (lru && lru->domain) {
 			ret = lru->data;
 			return ret;
@@ -802,7 +802,7 @@
 	}
  leave:
 	if (lru)
-		lru64_commit(lru, ret, expr, expr->revision, NULL);
+		lru64_commit(lru, ret, expr, expr->ref->revision, NULL);
 
 	return ret;
 }
@@ -1101,7 +1101,7 @@
 	free_pattern_tree(&expr->pattern_tree);
 	free_pattern_tree(&expr->pattern_tree_2);
 	LIST_INIT(&expr->patterns);
-	expr->revision = rdtsc();
+	expr->ref->revision = rdtsc();
 }
 
 void pat_prune_ptr(struct pattern_expr *expr)
@@ -1118,7 +1118,7 @@
 	free_pattern_tree(&expr->pattern_tree);
 	free_pattern_tree(&expr->pattern_tree_2);
 	LIST_INIT(&expr->patterns);
-	expr->revision = rdtsc();
+	expr->ref->revision = rdtsc();
 }
 
 void pat_prune_reg(struct pattern_expr *expr)
@@ -1135,7 +1135,7 @@
 	free_pattern_tree(&expr->pattern_tree);
 	free_pattern_tree(&expr->pattern_tree_2);
 	LIST_INIT(&expr->patterns);
-	expr->revision = rdtsc();
+	expr->ref->revision = rdtsc();
 }
 
 /*
@@ -1160,7 +1160,7 @@
 
 	/* chain pattern in the expression */
 	LIST_ADDQ(&expr->patterns, &patl->list);
-	expr->revision = rdtsc();
+	expr->ref->revision = rdtsc();
 
 	/* that's ok */
 	return 1;
@@ -1189,7 +1189,7 @@
 
 	/* chain pattern in the expression */
 	LIST_ADDQ(&expr->patterns, &patl->list);
-	expr->revision = rdtsc();
+	expr->ref->revision = rdtsc();
 
 	/* that's ok */
 	return 1;
@@ -1219,7 +1219,7 @@
 
 	/* chain pattern in the expression */
 	LIST_ADDQ(&expr->patterns, &patl->list);
-	expr->revision = rdtsc();
+	expr->ref->revision = rdtsc();
 
 	/* that's ok */
 	return 1;
@@ -1248,7 +1248,7 @@
 
 	/* chain pattern in the expression */
 	LIST_ADDQ(&expr->patterns, &patl->list);
-	expr->revision = rdtsc();
+	expr->ref->revision = rdtsc();
 
 	/* that's ok */
 	return 1;
@@ -1297,7 +1297,7 @@
 
 			/* Insert the entry. */
 			ebmb_insert_prefix(&expr->pattern_tree, &node->node, 4);
-			expr->revision = rdtsc();
+			expr->ref->revision = rdtsc();
 
 			/* that's ok */
 			return 1;
@@ -1325,7 +1325,7 @@
 
 		/* Insert the entry. */
 		ebmb_insert_prefix(&expr->pattern_tree_2, &node->node, 16);
-		expr->revision = rdtsc();
+		expr->ref->revision = rdtsc();
 
 		/* that's ok */
 		return 1;
@@ -1369,7 +1369,7 @@
 
 	/* index the new node */
 	ebst_insert(&expr->pattern_tree, &node->node);
-	expr->revision = rdtsc();
+	expr->ref->revision = rdtsc();
 
 	/* that's ok */
 	return 1;
@@ -1411,7 +1411,7 @@
 
 	/* index the new node */
 	ebmb_insert_prefix(&expr->pattern_tree, &node->node, len);
-	expr->revision = rdtsc();
+	expr->ref->revision = rdtsc();
 
 	/* that's ok */
 	return 1;
@@ -1432,7 +1432,7 @@
 		free(pat->pat.data);
 		free(pat);
 	}
-	expr->revision = rdtsc();
+	expr->ref->revision = rdtsc();
 }
 
 void pat_del_tree_ip(struct pattern_expr *expr, struct pat_ref_elt *ref)
@@ -1476,7 +1476,7 @@
 		free(elt->data);
 		free(elt);
 	}
-	expr->revision = rdtsc();
+	expr->ref->revision = rdtsc();
 }
 
 void pat_del_list_ptr(struct pattern_expr *expr, struct pat_ref_elt *ref)
@@ -1495,7 +1495,7 @@
 		free(pat->pat.data);
 		free(pat);
 	}
-	expr->revision = rdtsc();
+	expr->ref->revision = rdtsc();
 }
 
 void pat_del_tree_str(struct pattern_expr *expr, struct pat_ref_elt *ref)
@@ -1523,7 +1523,7 @@
 		free(elt->data);
 		free(elt);
 	}
-	expr->revision = rdtsc();
+	expr->ref->revision = rdtsc();
 }
 
 void pat_del_list_reg(struct pattern_expr *expr, struct pat_ref_elt *ref)
@@ -1542,13 +1542,12 @@
 		free(pat->pat.data);
 		free(pat);
 	}
-	expr->revision = rdtsc();
+	expr->ref->revision = rdtsc();
 }
 
 void pattern_init_expr(struct pattern_expr *expr)
 {
 	LIST_INIT(&expr->patterns);
-	expr->revision = 0;
 	expr->pattern_tree = EB_ROOT;
 	expr->pattern_tree_2 = EB_ROOT;
 }
@@ -1853,6 +1852,7 @@
 
 	ref->flags = flags;
 	ref->unique_id = -1;
+	ref->revision = 0;
 
 	LIST_INIT(&ref->head);
 	LIST_INIT(&ref->pat);