Use coarse monotonic timer instead of cached monotonized libevent time.

src/or/buffers.c

@@ -405,7 +405,7 @@ static chunk_t *
 buf_add_chunk_with_capacity(buf_t *buf, size_t capacity, int capped)
 {
   chunk_t *chunk;
-  struct timeval now;
+
   if (CHUNK_ALLOC_SIZE(capacity) < buf->default_chunk_size) {
     chunk = chunk_new_with_alloc_size(buf->default_chunk_size);
   } else if (capped && CHUNK_ALLOC_SIZE(capacity) > MAX_CHUNK_ALLOC) {
@@ -414,8 +414,7 @@ buf_add_chunk_with_capacity(buf_t *buf, size_t capacity, int capped)
     chunk = chunk_new_with_alloc_size(preferred_chunk_size(capacity));
   }
 
-  tor_gettimeofday_cached_monotonic(&now);
-  chunk->inserted_time = (uint32_t)tv_to_msec(&now);
+  chunk->inserted_time = (uint32_t)monotime_coarse_absolute_msec();
 
   if (buf->tail) {
     tor_assert(buf->head);
@@ -430,8 +429,8 @@ buf_add_chunk_with_capacity(buf_t *buf, size_t capacity, int capped)
 }
 
 /** Return the age of the oldest chunk in the buffer <b>buf</b>, in
- * milliseconds.  Requires the current time, in truncated milliseconds since
- * the epoch, as its input <b>now</b>.
+ * milliseconds.  Requires the current monotonic time, in truncated msec,
+ * as its input <b>now</b>.
  */
 uint32_t
 buf_get_oldest_chunk_timestamp(const buf_t *buf, uint32_t now)

src/or/circuitlist.c

@@ -2015,7 +2015,7 @@ circuit_max_queued_cell_age(const circuit_t *c, uint32_t now)
 
 /** Return the age in milliseconds of the oldest buffer chunk on <b>conn</b>,
  * where age is taken in milliseconds before the time <b>now</b> (in truncated
- * milliseconds since the epoch).  If the connection has no data, treat
+ * absolute monotonic msec).  If the connection has no data, treat
  * it as having age zero.
  **/
 static uint32_t
@@ -2138,7 +2138,6 @@ circuits_handle_oom(size_t current_allocation)
   size_t mem_recovered=0;
   int n_circuits_killed=0;
   int n_dirconns_killed=0;
-  struct timeval now;
   uint32_t now_ms;
   log_notice(LD_GENERAL, "We're low on memory.  Killing circuits with "
              "over-long queues. (This behavior is controlled by "
@@ -2152,8 +2151,7 @@ circuits_handle_oom(size_t current_allocation)
     mem_to_recover = current_allocation - mem_target;
   }
 
-  tor_gettimeofday_cached_monotonic(&now);
-  now_ms = (uint32_t)tv_to_msec(&now);
+  now_ms = (uint32_t)monotime_coarse_absolute_msec();
 
   circlist = circuit_get_global_list();
   SMARTLIST_FOREACH_BEGIN(circlist, circuit_t *, circ) {

src/or/relay.c

@@ -2320,14 +2320,12 @@ cell_queue_append_packed_copy(circuit_t *circ, cell_queue_t *queue,
                               int exitward, const cell_t *cell,
                               int wide_circ_ids, int use_stats)
 {
-  struct timeval now;
   packed_cell_t *copy = packed_cell_copy(cell, wide_circ_ids);
   (void)circ;
   (void)exitward;
   (void)use_stats;
-  tor_gettimeofday_cached_monotonic(&now);
 
-  copy->inserted_time = (uint32_t)tv_to_msec(&now);
+  copy->inserted_time = (uint32_t) monotime_coarse_absolute_msec();
 
   cell_queue_append(queue, copy);
 }