commit 41dfc4c19c4e0ee37d092fa0ed7faf349e6ab467 Author: Nick Mathewson nickm@torproject.org Date: Wed Sep 7 22:00:48 2011 -0400

Make bufferevents work with TokenBucketRefillInterval --- doc/tor.1.txt | 3 +-- src/common/compat_libevent.c | 34 +++++++++++++++++++++------------- src/common/compat_libevent.h | 2 +- src/or/config.c | 1 + src/or/connection.c | 5 ++++- src/or/connection_or.c | 7 ++++++- 6 files changed, 34 insertions(+), 18 deletions(-)

diff --git a/doc/tor.1.txt b/doc/tor.1.txt index 15f5a21..4ae721e 100644 --- a/doc/tor.1.txt +++ b/doc/tor.1.txt @@ -742,8 +742,7 @@ The following options are useful only for clients (that is, if NUM must be between 1 and 1000, inclusive. Note that the configured bandwidth limits are still expressed in bytes per second: this option only affects the frequency with which Tor checks to see whether - previously exhausted connections may read again. This option is - if Tor was built with Libevent's bufferevents enabled. (Default: 10 msec.) + previously exhausted connections may read again. (Default: 10 msec.)

**TrackHostExits** __host__,__.domain__,__...__:: For each value in the comma separated list, Tor will track recent diff --git a/src/common/compat_libevent.c b/src/common/compat_libevent.c index beae950..3201738 100644 --- a/src/common/compat_libevent.c +++ b/src/common/compat_libevent.c @@ -169,6 +169,7 @@ struct event_base *the_event_base = NULL;

#ifdef USE_BUFFEREVENTS static int using_iocp_bufferevents = 0; +static void tor_libevent_set_tick_timeout(int msec_per_tick);

int tor_libevent_using_iocp_bufferevents(void) @@ -236,6 +237,10 @@ tor_libevent_initialize(tor_libevent_cfg *torcfg) "You have a *VERY* old version of libevent. It is likely to be buggy; " "please build Tor with a more recent version."); #endif + +#ifdef USE_BUFFEREVENTS + tor_libevent_set_tick_timeout(torcfg->msec_per_tick); +#endif }

/** Return the current Libevent event base that we're set up to use. */ @@ -598,26 +603,29 @@ static const struct timeval *one_tick = NULL; /** * Return a special timeout to be passed whenever libevent's O(1) timeout * implementation should be used. Only use this when the timer is supposed - * to fire after 1 / TOR_LIBEVENT_TICKS_PER_SECOND seconds have passed. + * to fire after msec_per_tick ticks have elapsed. */ const struct timeval * tor_libevent_get_one_tick_timeout(void) { - if (PREDICT_UNLIKELY(one_tick == NULL)) { - struct event_base *base = tor_libevent_get_base(); - struct timeval tv; - if (TOR_LIBEVENT_TICKS_PER_SECOND == 1) { - tv.tv_sec = 1; - tv.tv_usec = 0; - } else { - tv.tv_sec = 0; - tv.tv_usec = 1000000 / TOR_LIBEVENT_TICKS_PER_SECOND; - } - one_tick = event_base_init_common_timeout(base, &tv); - } + tor_assert(one_tick); return one_tick; }

+/** Initialize the common timeout that we'll use to refill the buckets every + * time a tick elapses. */ +static void +tor_libevent_set_tick_timeout(int msec_per_tick) +{ + struct event_base *base = tor_libevent_get_base(); + struct timeval tv; + + tor_assert(! one_tick); + tv.tv_sec = msec_per_tick / 1000; + tv.tv_usec = (msec_per_tick % 1000) * 1000; + one_tick = event_base_init_common_timeout(base, &tv); +} + static struct bufferevent * tor_get_root_bufferevent(struct bufferevent *bev) { diff --git a/src/common/compat_libevent.h b/src/common/compat_libevent.h index 15b0fc2..0247297 100644 --- a/src/common/compat_libevent.h +++ b/src/common/compat_libevent.h @@ -62,6 +62,7 @@ int tor_event_base_loopexit(struct event_base *base, struct timeval *tv); typedef struct tor_libevent_cfg { int disable_iocp; int num_cpus; + int msec_per_tick; } tor_libevent_cfg;

void tor_libevent_initialize(tor_libevent_cfg *cfg); @@ -73,7 +74,6 @@ void tor_check_libevent_header_compatibility(void); const char *tor_libevent_get_version_str(void);

#ifdef USE_BUFFEREVENTS -#define TOR_LIBEVENT_TICKS_PER_SECOND 3 const struct timeval *tor_libevent_get_one_tick_timeout(void); int tor_libevent_using_iocp_bufferevents(void); int tor_set_bufferevent_rate_limit(struct bufferevent *bev, diff --git a/src/or/config.c b/src/or/config.c index 5a7a590..e22f539 100644 --- a/src/or/config.c +++ b/src/or/config.c @@ -5645,6 +5645,7 @@ init_libevent(const or_options_t *options) memset(&cfg, 0, sizeof(cfg)); cfg.disable_iocp = options->DisableIOCP; cfg.num_cpus = get_num_cpus(options); + cfg.msec_per_tick = options->TokenBucketRefillInterval;

tor_libevent_initialize(&cfg);

diff --git a/src/or/connection.c b/src/or/connection.c index cb93a81..9dd9297 100644 --- a/src/or/connection.c +++ b/src/or/connection.c @@ -2561,7 +2561,10 @@ connection_bucket_init(void) burst = options->BandwidthBurst; }

- rate /= TOR_LIBEVENT_TICKS_PER_SECOND; + /* This can't overflow, since TokenBucketRefillInterval <= 1000, + * and rate started out less than INT32_MAX. */ + rate = (rate * options->TokenBucketRefillInterval) / 1000; + bucket_cfg = ev_token_bucket_cfg_new((uint32_t)rate, (uint32_t)burst, (uint32_t)rate, (uint32_t)burst, tick); diff --git a/src/or/connection_or.c b/src/or/connection_or.c index a75444e..29f0f8d 100644 --- a/src/or/connection_or.c +++ b/src/or/connection_or.c @@ -580,7 +580,12 @@ connection_or_update_token_buckets_helper(or_connection_t *conn, int reset, { const struct timeval *tick = tor_libevent_get_one_tick_timeout(); struct ev_token_bucket_cfg *cfg, *old_cfg; - int rate_per_tick = rate / TOR_LIBEVENT_TICKS_PER_SECOND; + int64_t rate64 = (((int64_t)rate) * options->TokenBucketRefillInterval) + / 1000; + /* This can't overflow, since TokenBucketRefillInterval <= 1000, + * and rate started out less than INT_MAX. */ + int rate_per_tick = (int) rate64; + cfg = ev_token_bucket_cfg_new(rate_per_tick, burst, rate_per_tick, burst, tick); old_cfg = conn->bucket_cfg;