Commit d44e3ad8 authored by Nick Mathewson's avatar Nick Mathewson 🐘
Browse files

Remove unused open circuits when there are too many, not when they are too old. 


svn:r1332
parent b3f6b55e

src/or/circuit.c

+33 −20
Changes for src/or/circuit.c: 33 added lines, 20 removed lines.
Original line number Diff line number Diff line
@@ -18,6 +18,7 @@ unsigned long stats_n_relay_cells_delivered = 0; 


/********* START VARIABLES **********/



static int circuitlist_len=0;

static circuit_t *global_circuitlist=NULL;

char *circuit_state_to_string[] = {

  "doing handshakes",        /* 0 */
@@ -36,6 +37,7 @@ void circuit_add(circuit_t *circ) { 
    circ->next = global_circuitlist;

    global_circuitlist = circ;

  }

  ++circuitlist_len;

}



void circuit_remove(circuit_t *circ) {
@@ -45,12 +47,14 @@ void circuit_remove(circuit_t *circ) { 


  if(global_circuitlist == circ) {

    global_circuitlist = global_circuitlist->next;

    --circuitlist_len;

    return;

  }



  for(tmpcirc = global_circuitlist;tmpcirc->next;tmpcirc = tmpcirc->next) {

    if(tmpcirc->next == circ) {

      tmpcirc->next = circ->next;

      --circuitlist_len;

      return;

    }

  }
@@ -61,7 +65,6 @@ void circuit_close_all_marked() 
  circuit_t *tmp,*m;



  while (global_circuitlist && global_circuitlist->marked_for_close) {

    

    tmp = global_circuitlist->next;

    circuit_free(global_circuitlist);

    global_circuitlist = tmp;
@@ -907,34 +910,44 @@ void circuit_dump_by_conn(connection_t *conn, int severity) { 
  }

}



/* Expire unused testing circuits after 10 minutes. */

#define TESTING_CIRCUIT_MAX_AGE 600

/* Don't keep more than 10 unused open circuits around. */

#define MAX_UNUSED_OPEN_CIRCUITS 10



void circuit_expire_unused_circuits(void) {

  circuit_t *circ, *tmpcirc;

  circuit_t *circ;

  time_t now = time(NULL);

  smartlist_t *unused_open_circs;

  int i;



  circ = global_circuitlist;

  while(circ) {

    tmpcirc = circ;

    circ = circ->next;

  unused_open_circs = smartlist_create(circuitlist_len);



  for (circ = global_circuitlist; circ; circ = circ->next) {

    if (circ->marked_for_close)

      continue;

    /* If the circuit has been dirty for too long, and there are no streams

     * on it, mark it for close.

     * If we are creating test circuits, and the circuit is old, and has

     * no streams, shut it down even if it isn't dirty.

     */

    if(((tmpcirc->timestamp_dirty &&

         tmpcirc->timestamp_dirty + options.NewCircuitPeriod < now) ||

        (options.RunTesting &&

         tmpcirc->cpath &&

         tmpcirc->timestamp_created + TESTING_CIRCUIT_MAX_AGE < now))

       && !tmpcirc->p_conn

       && !tmpcirc->p_streams

       && !tmpcirc->marked_for_close) {

      log_fn(LOG_DEBUG,"Closing n_circ_id %d",tmpcirc->n_circ_id);

      circuit_mark_for_close(tmpcirc);

    if (circ->timestamp_dirty &&

        circ->timestamp_dirty + options.NewCircuitPeriod < now &&

        !circ->p_conn &&

        !circ->p_streams) {

      log_fn(LOG_DEBUG,"Closing n_circ_id %d",circ->n_circ_id);

      circuit_mark_for_close(circ);

    } else if (!circ->timestamp_dirty && circ->cpath &&

               circ->state == CIRCUIT_STATE_OPEN) {

      /* Also, gather a list of open unused circuits that we created.

       * Because we add elements to the front of global_circuitlist,

       * the last elements of unused_open_circs will be the oldest

       * ones.

       */

      smartlist_add(unused_open_circs, circ);

    }

  }

  for (i = MAX_UNUSED_OPEN_CIRCUITS; i < unused_open_circs->num_used; ++i) {

    circuit_t *circ=(circuit_t*)(unused_open_circs->list[i]);

    circuit_mark_for_close(circ);

  }

  smartlist_free(unused_open_circs);

}



/* Number of consecutive failures so far; should only be touched by