From: Vsevolod Stakhov <vsevolod@rspamd.com>
Date: Sat, 18 Apr 2026 10:44:17 +0000 (+0100)
Subject: [Feature] async_session: annotate DNS and TCP events with operation labels
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6e31a90314ab7d6c7dd4af080f919b68efa5edf9;p=thirdparty%2Frspamd.git

[Feature] async_session: annotate DNS and TCP events with operation labels

Add rspamd_session_event_update_label() for mutating a live event's
label field, and use it to give operators a better idea of what a
long-lived event is waiting on at timeout time:

  - dns.c: pass rdns_strtype(type) ("A" / "AAAA" / "TXT" / ...) as the
    label at add time, so timeout logs show which record type stalled.
  - lua_tcp.c: update the label as the per-connection event transitions
    between operations ("tcp connect" / "tcp write" / "tcp read").

Timeout summary now reads
  "rspamd dns[RBL_FOO/A]=3, rspamd lua tcp[RULE/tcp read]=1"
instead of just "rspamd dns=3, rspamd lua tcp=1".
---

diff --git a/src/libserver/async_session.c b/src/libserver/async_session.c
index 1835b6635b..50febb8b00 100644
--- a/src/libserver/async_session.c
+++ b/src/libserver/async_session.c
@@ -190,6 +190,14 @@ rspamd_session_add_event_full(struct rspamd_async_session *session,
 	return new_event;
 }
 
+void rspamd_session_event_update_label(struct rspamd_async_event *ev,
+									   const char *label)
+{
+	if (ev != NULL) {
+		ev->label = label;
+	}
+}
+
 void rspamd_session_remove_event(struct rspamd_async_session *session,
 								 event_finalizer_t fin,
 								 void *ud)
diff --git a/src/libserver/async_session.h b/src/libserver/async_session.h
index 6746851c10..42ba570ed1 100644
--- a/src/libserver/async_session.h
+++ b/src/libserver/async_session.h
@@ -82,6 +82,18 @@ rspamd_session_add_event_full(struct rspamd_async_session *session,
 #define rspamd_session_add_event(session, fin, user_data, subsystem) \
 	rspamd_session_add_event_full(session, fin, user_data, subsystem, NULL)
 
+/**
+ * Updates the label (human annotation) of an already-registered event.
+ * Intended for callers whose event is long-lived (e.g. a TCP connection)
+ * and whose "current operation" (read / write / connect) changes during
+ * the event's lifetime. The new label must remain valid until the event
+ * is removed or the label is updated again.
+ * @param ev event returned by rspamd_session_add_event[_full]; may be NULL (no-op)
+ * @param label new label or NULL to clear
+ */
+void rspamd_session_event_update_label(struct rspamd_async_event *ev,
+									   const char *label);
+
 /**
  * Remove normal event
  * @param session session object
diff --git a/src/libserver/dns.c b/src/libserver/dns.c
index 2c108c5679..ad5cf8e759 100644
--- a/src/libserver/dns.c
+++ b/src/libserver/dns.c
@@ -268,10 +268,11 @@ rspamd_dns_resolver_request(struct rspamd_dns_resolver *resolver,
 
 	if (session) {
 		if (req != NULL) {
-			rspamd_session_add_event(session,
-									 (event_finalizer_t) rspamd_dns_fin_cb,
-									 reqdata,
-									 M);
+			rspamd_session_add_event_full(session,
+										  (event_finalizer_t) rspamd_dns_fin_cb,
+										  reqdata,
+										  M,
+										  rdns_strtype(type));
 		}
 	}
 
diff --git a/src/lua/lua_tcp.c b/src/lua/lua_tcp.c
index 7fb9e0bfe6..f660e70292 100644
--- a/src/lua/lua_tcp.c
+++ b/src/lua/lua_tcp.c
@@ -1217,6 +1217,7 @@ lua_tcp_plan_handler_event(struct lua_tcp_cbdata *cbd, gboolean can_read,
 	}
 	else {
 		if (hdl->type == LUA_WANT_READ) {
+			rspamd_session_event_update_label(cbd->async_ev, "tcp read");
 
 			/* We need to check if we have some leftover in the buffer */
 			if (cbd->in->len > 0) {
@@ -1247,6 +1248,7 @@ lua_tcp_plan_handler_event(struct lua_tcp_cbdata *cbd, gboolean can_read,
 			}
 		}
 		else if (hdl->type == LUA_WANT_WRITE) {
+			rspamd_session_event_update_label(cbd->async_ev, "tcp write");
 			/*
 			 * We need to plan write event if there is something in the
 			 * write request
@@ -1273,6 +1275,7 @@ lua_tcp_plan_handler_event(struct lua_tcp_cbdata *cbd, gboolean can_read,
 			}
 		}
 		else { /* LUA_WANT_CONNECT */
+			rspamd_session_event_update_label(cbd->async_ev, "tcp connect");
 			msg_debug_tcp("plan new connect");
 			rspamd_ev_watcher_reschedule(cbd->event_loop, &cbd->ev,
 										 EV_WRITE);