From: W.C.A. Wijngaards <wouter@nlnetlabs.nl>
Date: Thu, 23 Jan 2020 09:34:38 +0000 (+0100)
Subject: dtio_find_msg loop roundrobin instead of first queue only, with
X-Git-Tag: 1.11.0rc1~120^2~96
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=14d76588973715f63753cd884b5f5791f52a42ca;p=thirdparty%2Funbound.git

dtio_find_msg loop roundrobin instead of first queue only, with
state in the dtio struct for loop iterator.
---

diff --git a/dnstap/dtstream.c b/dnstap/dtstream.c
index e414d5d02..c3270a008 100644
--- a/dnstap/dtstream.c
+++ b/dnstap/dtstream.c
@@ -221,6 +221,7 @@ int dt_io_thread_register_queue(struct dt_io_thread* dtio,
 	item->queue = mq;
 	item->next = dtio->io_list;
 	dtio->io_list = item;
+	dtio->io_list_iter = NULL;
 	return 1;
 }
 
@@ -235,6 +236,7 @@ void dt_io_thread_unregister_queue(struct dt_io_thread* dtio,
 			else dtio->io_list = item->next;
 			/* the queue itself only registered, not deleted */
 			free(item);
+			dtio->io_list_iter = NULL;
 			return;
 		}
 		prev = item;
@@ -283,7 +285,16 @@ static int dtio_find_in_queue(struct dt_io_thread* dtio,
 /** find a new message to write, search message queues, false if none */
 static int dtio_find_msg(struct dt_io_thread* dtio)
 {
-	struct dt_io_list_item* item = dtio->io_list;
+	struct dt_io_list_item* item;
+
+	if(dtio->io_list_iter)
+		item = dtio->io_list_iter;
+	else	item = dtio->io_list;
+	/* use the next queue for the next message lookup,
+	 * if we hit the end(NULL) the NULL restarts the iter at start. */
+	if(item)
+		dtio->io_list_iter = item->next;
+
 	while(item) {
 		if(dtio_find_in_queue(dtio, item->queue))
 			return 1;
diff --git a/dnstap/dtstream.h b/dnstap/dtstream.h
index 7641ffbd6..3c5bd9a4e 100644
--- a/dnstap/dtstream.h
+++ b/dnstap/dtstream.h
@@ -93,6 +93,10 @@ struct dt_io_thread {
 	void* event_base;
 	/** list of queues that is registered to get written */
 	struct dt_io_list_item* io_list;
+	/** iterator point in the io_list, to pick from them in a
+	 * round-robin fashion, instead of only from the first when busy.
+	 * if NULL it means start at the start of the list. */
+	struct dt_io_list_item* io_list_iter;
 	/** thread id, of the io thread */
 	ub_thread_type tid;
 	/** file descriptor that the thread writes to */