Pop all pending control messages when the read event fires

Under extreme load not all messages get popped, eventually leading to a
full ring buffer and so collapse of the control signalling.

diff --git a/src/lib/io/control.c b/src/lib/io/control.c
index 8653e50db33a73173dabb2a91510541bb0961ee0..ffd94466f771b28b23e130216fe8ea5f906eb17d 100644 (file)
--- a/src/lib/io/control.c
+++ b/src/lib/io/control.c
@@ -91,23 +91,17 @@ struct fr_control_s {
 static void pipe_read(UNUSED fr_event_list_t *el, int fd, UNUSED int flags, void *uctx)
 {
        fr_control_t *c = talloc_get_type_abort(uctx, fr_control_t);
-       ssize_t i, num;
        fr_time_t now;
        char read_buffer[256];
        uint8_t data[256];
+       size_t message_size;
+       uint32_t id = 0;
 
-       num = read(fd, read_buffer, sizeof(read_buffer));
-       if (num <= 0) return;
+       if (read(fd, read_buffer, sizeof(read_buffer)) <= 0) return;
 
        now = fr_time();
 
-       for (i = 0; i < num; i++) {
-               uint32_t id = 0;
-               size_t message_size;
-
-               message_size = fr_control_message_pop(c->aq, &id, data, sizeof(data));
-               if (!message_size) return;
-
+       while((message_size = fr_control_message_pop(c->aq, &id, data, sizeof(data)))) {
                if (id >= FR_CONTROL_MAX_TYPES) continue;
 
                if (!c->type[id].callback) continue;