Reduce how often we have to poll the packet queue.

Packets are moved to the MeshLink thread via the packet queue. However,
each packet required a trigger byte to be sent to the event loop, requiring
more calls to select() than necessary. Now we make event loop signals level
triggered, and dequeue all enqueued packets at once.

This also adds debug log statements for the packet queue.

diff --git a/src/event.c b/src/event.c
index af1b0d60072e2dc19080fde9136f5126d4788d7f..11f1ed817003138cf4b2a7e4a3b7e45f341e8a12 100644 (file)
--- a/src/event.c
+++ b/src/event.c
@@ -171,6 +171,7 @@ static void signalio_handler(event_loop_t *loop, void *data, int flags) {
        });
 
        if(sig) {
+               sig->set = false;
                sig->cb(loop, sig->data);
        }
 }
@@ -195,7 +196,12 @@ static void pipe_exit(event_loop_t *loop) {
 }
 
 void signal_trigger(event_loop_t *loop, signal_t *sig) {
+       if(sig->set) {
+               return;
+       }
+
        uint8_t signum = sig->signum;
+       sig->set = true;
        write(loop->pipefd[1], &signum, 1);
        return;
 }
@@ -206,6 +212,7 @@ void signal_add(event_loop_t *loop, signal_t *sig, signal_cb_t cb, void *data, u
        sig->cb = cb;
        sig->data = data;
        sig->signum = signum;
+       sig->set = false;
        sig->node.data = sig;
 
        if(loop->pipefd[0] == -1) {

diff --git a/src/event.h b/src/event.h
index 8a61e81b2d20899d859b41f8fa21e348a90b6881..f2ebf4980085fb222804bad108a2c3705251664f 100644 (file)
--- a/src/event.h
+++ b/src/event.h
@@ -52,6 +52,7 @@ typedef struct timeout_t {
 typedef struct signal_t {
        struct splay_node_t node;
        int signum;
+       bool set;
        signal_cb_t cb;
        void *data;
 } signal_t;

diff --git a/src/meshlink.c b/src/meshlink.c
index 8513c8f99613ed6785789be189aafaa96759feb0..e1cf7979631e0f94b9ebf3f8f820afeb5a66197d 100644 (file)
--- a/src/meshlink.c
+++ b/src/meshlink.c
@@ -2008,6 +2008,8 @@ bool meshlink_send(meshlink_handle_t *mesh, meshlink_node_t *destination, const
                return false;
        }
 
+       logger(mesh, MESHLINK_DEBUG, "Adding packet of %zu bytes to packet queue", len);
+
        // Notify event loop
        signal_trigger(&mesh->loop, &mesh->datafromapp);
 
@@ -2017,17 +2019,16 @@ bool meshlink_send(meshlink_handle_t *mesh, meshlink_node_t *destination, const
 void meshlink_send_from_queue(event_loop_t *loop, void *data) {
        (void)loop;
        meshlink_handle_t *mesh = data;
-       vpn_packet_t *packet = meshlink_queue_pop(&mesh->outpacketqueue);
-
-       if(!packet) {
-               return;
-       }
 
-       mesh->self->in_packets++;
-       mesh->self->in_bytes += packet->len;
-       route(mesh, mesh->self, packet);
+       logger(mesh, MESHLINK_DEBUG, "Flushing the packet queue");
 
-       free(packet);
+       for(vpn_packet_t *packet; (packet = meshlink_queue_pop(&mesh->outpacketqueue));) {
+               logger(mesh, MESHLINK_DEBUG, "Removing packet of %d bytes from packet queue", packet->len);
+               mesh->self->in_packets++;
+               mesh->self->in_bytes += packet->len;
+               route(mesh, mesh->self, packet);
+               free(packet);
+       }
 }
 
 ssize_t meshlink_get_pmtu(meshlink_handle_t *mesh, meshlink_node_t *destination) {