commit 17ad309d33561ee255cac70bdb9a19803f2d8c08 Merge: fd9961d a770b74 Author: Nick Mathewson nickm@torproject.org Date: Wed Apr 23 12:44:18 2014 -0400
Merge remote-tracking branch 'public/bug11553_024' into bug11553_025
Conflicts: src/or/circuitbuild.c
src/or/channel.c | 3 +++ src/or/channel.h | 6 ++++-- src/or/circuitbuild.c | 19 +++++++++++++------ 3 files changed, 20 insertions(+), 8 deletions(-)
diff --cc src/or/channel.h index de19fad,63da0c1..bd9a02f --- a/src/or/channel.h +++ b/src/or/channel.h @@@ -146,16 -145,14 +146,14 @@@ struct channel_s * When we send CREATE cells along this connection, which half of the * space should we use? */ - ENUM_BF(circ_id_type_t) circ_id_type:2; + circ_id_type_bitfield_t circ_id_type:2; /** DOCDOC*/ unsigned wide_circ_ids:1; - /** Have we logged a warning about circID exhaustion on this channel? */ - unsigned warned_circ_ids_exhausted:1;
- /* For how many circuits are we n_chan? What about p_chan? */ + /** For how many circuits are we n_chan? What about p_chan? */ unsigned int num_n_circuits, num_p_circuits;
- /* + /** * True iff this channel shouldn't get any new circs attached to it, * because the connection is too old, or because there's a better one. * More generally, this flag is used to note an unhealthy connection; diff --cc src/or/circuitbuild.c index 550ed1c,8d6aad6..9e11a0b --- a/src/or/circuitbuild.c +++ b/src/or/circuitbuild.c @@@ -87,9 -102,14 +87,15 @@@ channel_connect_for_circuit(const tor_a static circid_t get_unique_circ_id_by_chan(channel_t *chan) { + /* This number is chosen somewhat arbitrarily; see comment below for more + * info. When the space is 80% full, it gives a one-in-a-million failure + * chance; when the space is 90% full, it gives a one-in-850 chance; and when + * the space is 95% full, it gives a one-in-26 failure chance. That seems + * okay, though you could make a case IMO for anything between N=32 and + * N=256. */ #define MAX_CIRCID_ATTEMPTS 64 - + int in_use; + unsigned n_with_circ = 0, n_pending_destroy = 0; circid_t test_circ_id; circid_t attempts=0; circid_t high_bit, max_range, mask; @@@ -123,30 -143,22 +129,31 @@@ * whole circuit ID space every time we extend a circuit, which is * not so great either. */ - if (! chan->warned_circ_ids_exhausted) { - chan->warned_circ_ids_exhausted = 1; - log_warn(LD_CIRC,"No unused circIDs found on channel %s wide " + log_fn_ratelim(&chan->last_warned_circ_ids_exhausted, LOG_WARN, + LD_CIRC,"No unused circIDs found on channel %s wide " "circID support, with %u inbound and %u outbound circuits. " + "Found %u circuit IDs in use by circuits, and %u with " + "pending destroy cells." "Failing a circuit.", chan->wide_circ_ids ? "with" : "without", - chan->num_p_circuits, chan->num_n_circuits); + chan->num_p_circuits, chan->num_n_circuits, + n_with_circ, n_pending_destroy); return 0; }
- crypto_rand((char*) &test_circ_id, sizeof(test_circ_id)); - test_circ_id &= mask; + do { + crypto_rand((char*) &test_circ_id, sizeof(test_circ_id)); + test_circ_id &= mask; + } while (test_circ_id == 0); + test_circ_id |= high_bit; - } while (circuit_id_in_use_on_channel(test_circ_id, chan)); + + in_use = circuit_id_in_use_on_channel(test_circ_id, chan); + if (in_use == 1) + ++n_with_circ; + else if (in_use == 2) + ++n_pending_destroy; + } while (in_use); return test_circ_id; }