Merge remote-tracking branch 'public/bug10169_023' into bug10169_024

Conflicts:
	src/or/relay.c

src/common/compat_libevent.c

@@ -653,3 +653,33 @@ tor_gettimeofday_cache_clear(void)
 }
 #endif
 
+/**
+ * As tor_gettimeofday_cached, but can never move backwards in time.
+ *
+ * The returned value may diverge from wall-clock time, since wall-clock time
+ * can trivially be adjusted backwards, and this can't.  Don't mix wall-clock
+ * time with these values in the same calculation.
+ *
+ * Depending on implementation, this function may or may not "smooth out" huge
+ * jumps forward in wall-clock time.  It may or may not keep its results
+ * advancing forward (as opposed to stalling) if the wall-clock time goes
+ * backwards.  The current implementation does neither of of these.
+ *
+ * This function is not thread-safe; do not call it outside the main thread.
+ *
+ * In future versions of Tor, this may return a time does not have its
+ * origin at the Unix epoch.
+ */
+void
+tor_gettimeofday_cached_monotonic(struct timeval *tv)
+{
+  struct timeval last_tv = { 0, 0 };
+
+  tor_gettimeofday_cached(tv);
+  if (timercmp(tv, &last_tv, <)) {
+    memcpy(tv, &last_tv, sizeof(struct timeval));
+  } else {
+    memcpy(&last_tv, tv, sizeof(struct timeval));
+  }
+}
+

src/common/compat_libevent.h

@@ -90,6 +90,7 @@ int tor_add_bufferevent_to_rate_limit_group(struct bufferevent *bev,
 
 void tor_gettimeofday_cached(struct timeval *tv);
 void tor_gettimeofday_cache_clear(void);
+void tor_gettimeofday_cached_monotonic(struct timeval *tv);
 
 #endif
 

src/or/buffers.c

@@ -631,7 +631,7 @@ 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(&now);
+  tor_gettimeofday_cached_monotonic(&now);
   chunk->inserted_time = (uint32_t)tv_to_msec(&now);
 
   if (buf->tail) {

src/or/circuitlist.c

@@ -1693,7 +1693,7 @@ circuits_handle_oom(size_t current_allocation)
     mem_to_recover = current_allocation - mem_target;
   }
 
-  tor_gettimeofday_cached(&now);
+  tor_gettimeofday_cached_monotonic(&now);
   now_ms = (uint32_t)tv_to_msec(&now);
 
   /* This algorithm itself assumes that you've got enough memory slack
@@ -1731,9 +1731,11 @@ circuits_handle_oom(size_t current_allocation)
   buf_shrink_freelists(1); /* This is necessary to actually release buffer
                               chunks. */
 
-  log_notice(LD_GENERAL, "Removed "U64_FORMAT" bytes by killing %d circuits.",
+  log_notice(LD_GENERAL, "Removed "U64_FORMAT" bytes by killing %d circuits; "
+             "%d circuits remain alive.",
              U64_PRINTF_ARG(mem_recovered),
-             n_circuits_killed);
+             n_circuits_killed,
+             smartlist_len(circlist) - n_circuits_killed);
 
   smartlist_free(circlist);
 }

src/or/relay.c

@@ -2151,7 +2151,8 @@ cell_queue_append_packed_copy(cell_queue_t *queue, const cell_t *cell,
 {
   struct timeval now;
   packed_cell_t *copy = packed_cell_copy(cell, wide_circ_ids);
-  tor_gettimeofday_cached(&now);
+  tor_gettimeofday_cached_monotonic(&now);
+
   copy->inserted_time = (uint32_t)tv_to_msec(&now);
 
   /* Remember the time when this cell was put in the queue. */