Merge branch 'token_bucket_once_again_squashed'

src/common/token_bucket.c

@@ -9,8 +9,9 @@
  * Tor uses these token buckets to keep track of bandwidth usage, and
  * sometimes other things too.
  *
- * The time units we use internally are based on "timestamp" units -- see
- * monotime_coarse_to_stamp() for a rationale.
+ * There are two layers of abstraction here: "raw" token buckets, in which all
+ * the pieces are decoupled, and "read-write" token buckets, which combine all
+ * the moving parts into one.
  *
  * Token buckets may become negative.
  **/
@@ -20,6 +21,92 @@
 #include "token_bucket.h"
 #include "util_bug.h"
 
+/**
+ * Set the <b>rate</b> and <b>burst</b> value in a token_bucket_cfg.
+ *
+ * Note that the <b>rate</b> value is in arbitrary units, but those units will
+ * determine the units of token_bucket_raw_dec(), token_bucket_raw_refill, and
+ * so on.
+ */
+void
+token_bucket_cfg_init(token_bucket_cfg_t *cfg,
+                      uint32_t rate,
+                      uint32_t burst)
+{
+  tor_assert_nonfatal(rate > 0);
+  tor_assert_nonfatal(burst > 0);
+  if (burst > TOKEN_BUCKET_MAX_BURST)
+    burst = TOKEN_BUCKET_MAX_BURST;
+
+  cfg->rate = rate;
+  cfg->burst = burst;
+}
+
+/**
+ * Initialize a raw token bucket and its associated timestamp to the "full"
+ * state, according to <b>cfg</b>.
+ */
+void
+token_bucket_raw_reset(token_bucket_raw_t *bucket,
+                       const token_bucket_cfg_t *cfg)
+{
+  bucket->bucket = cfg->burst;
+}
+
+/**
+ * Adust a preexisting token bucket to respect the new configuration
+ * <b>cfg</b>, by decreasing its current level if needed. */
+void
+token_bucket_raw_adjust(token_bucket_raw_t *bucket,
+                        const token_bucket_cfg_t *cfg)
+{
+  bucket->bucket = MIN(bucket->bucket, cfg->burst);
+}
+
+/**
+ * Given an amount of <b>elapsed</b> time units, and a bucket configuration
+ * <b>cfg</b>, refill the level of <b>bucket</b> accordingly.  Note that the
+ * units of time in <b>elapsed</b> must correspond to those used to set the
+ * rate in <b>cfg</b>, or the result will be illogical.
+ */
+int
+token_bucket_raw_refill_steps(token_bucket_raw_t *bucket,
+                              const token_bucket_cfg_t *cfg,
+                              const uint32_t elapsed)
+{
+  const int was_empty = (bucket->bucket <= 0);
+  /* The casts here prevent an underflow.
+   *
+   * Note that even if the bucket value is negative, subtracting it from
+   * "burst" will still produce a correct result.  If this result is
+   * ridiculously high, then the "elapsed > gap / rate" check below
+   * should catch it. */
+  const size_t gap = ((size_t)cfg->burst) - ((size_t)bucket->bucket);
+
+  if (elapsed > gap / cfg->rate) {
+    bucket->bucket = cfg->burst;
+  } else {
+    bucket->bucket += cfg->rate * elapsed;
+  }
+
+  return was_empty && bucket->bucket > 0;
+}
+
+/**
+ * Decrement a provided bucket by <b>n</b> units.  Note that <b>n</b>
+ * must be nonnegative.
+ */
+int
+token_bucket_raw_dec(token_bucket_raw_t *bucket,
+                     ssize_t n)
+{
+  if (BUG(n < 0))
+    return 0;
+  const int becomes_empty = bucket->bucket > 0 && n >= bucket->bucket;
+  bucket->bucket -= n;
+  return becomes_empty;
+}
+
 /** Convert a rate in bytes per second to a rate in bytes per step */
 static uint32_t
 rate_per_sec_to_rate_per_step(uint32_t rate)
@@ -30,8 +117,9 @@ rate_per_sec_to_rate_per_step(uint32_t rate)
     (rate / 1000) * to_approximate_msec(TICKS_PER_STEP).  But to minimize
     rounding error, we do it this way instead, and divide last.
   */
-  return (uint32_t)
+  uint32_t val = (uint32_t)
     monotime_coarse_stamp_units_to_approx_msec(rate*TICKS_PER_STEP)/1000;
+  return val ? val : 1;
 }
 
 /**
@@ -41,14 +129,14 @@ rate_per_sec_to_rate_per_step(uint32_t rate)
  * starts out full.
  */
 void
-token_bucket_init(token_bucket_t *bucket,
+token_bucket_rw_init(token_bucket_rw_t *bucket,
                   uint32_t rate,
                   uint32_t burst,
                   uint32_t now_ts)
 {
-  memset(bucket, 0, sizeof(token_bucket_t));
-  token_bucket_adjust(bucket, rate, burst);
-  token_bucket_reset(bucket, now_ts);
+  memset(bucket, 0, sizeof(token_bucket_rw_t));
+  token_bucket_rw_adjust(bucket, rate, burst);
+  token_bucket_rw_reset(bucket, now_ts);
 }
 
 /**
@@ -56,56 +144,27 @@ token_bucket_init(token_bucket_t *bucket,
  * for the token bucket in *<b>bucket</b>.
  */
 void
-token_bucket_adjust(token_bucket_t *bucket,
-                    uint32_t rate,
-                    uint32_t burst)
+token_bucket_rw_adjust(token_bucket_rw_t *bucket,
+                       uint32_t rate,
+                       uint32_t burst)
 {
-  tor_assert_nonfatal(rate > 0);
-  tor_assert_nonfatal(burst > 0);
-  if (burst > TOKEN_BUCKET_MAX_BURST)
-    burst = TOKEN_BUCKET_MAX_BURST;
-
-  bucket->rate = rate_per_sec_to_rate_per_step(rate);
-  bucket->burst = burst;
-  bucket->read_bucket = MIN(bucket->read_bucket, (int32_t)burst);
-  bucket->write_bucket = MIN(bucket->write_bucket, (int32_t)burst);
+  token_bucket_cfg_init(&bucket->cfg,
+                        rate_per_sec_to_rate_per_step(rate),
+                        burst);
+  token_bucket_raw_adjust(&bucket->read_bucket, &bucket->cfg);
+  token_bucket_raw_adjust(&bucket->write_bucket, &bucket->cfg);
 }
 
 /**
  * Reset <b>bucket</b> to be full, as of timestamp <b>now_ts</b>.
  */
 void
-token_bucket_reset(token_bucket_t *bucket,
-                   uint32_t now_ts)
+token_bucket_rw_reset(token_bucket_rw_t *bucket,
+                      uint32_t now_ts)
 {
-  bucket->read_bucket = bucket->burst;
-  bucket->write_bucket = bucket->burst;
-  bucket->last_refilled_at_ts = now_ts;
-}
-
-/* Helper: see token_bucket_refill */
-static int
-refill_single_bucket(int32_t *bucketptr,
-                     const uint32_t rate,
-                     const int32_t burst,
-                     const uint32_t elapsed_steps)
-{
-  const int was_empty = (*bucketptr <= 0);
-  /* The casts here prevent an underflow.
-   *
-   * Note that even if the bucket value is negative, subtracting it from
-   * "burst" will still produce a correct result.  If this result is
-   * ridiculously high, then the "elapsed_steps > gap / rate" check below
-   * should catch it. */
-  const size_t gap = ((size_t)burst) - ((size_t)*bucketptr);
-
-  if (elapsed_steps > gap / rate) {
-    *bucketptr = burst;
-  } else {
-    *bucketptr += rate * elapsed_steps;
-  }
-
-  return was_empty && *bucketptr > 0;
+  token_bucket_raw_reset(&bucket->read_bucket, &bucket->cfg);
+  token_bucket_raw_reset(&bucket->write_bucket, &bucket->cfg);
+  bucket->last_refilled_at_timestamp = now_ts;
 }
 
 /**
@@ -116,10 +175,11 @@ refill_single_bucket(int32_t *bucketptr,
  * nonempty, and TB_WRITE iff the write bucket was empty and became nonempty.
  */
 int
-token_bucket_refill(token_bucket_t *bucket,
-                    uint32_t now_ts)
+token_bucket_rw_refill(token_bucket_rw_t *bucket,
+                       uint32_t now_ts)
 {
-  const uint32_t elapsed_ticks = (now_ts - bucket->last_refilled_at_ts);
+  const uint32_t elapsed_ticks =
+    (now_ts - bucket->last_refilled_at_timestamp);
   if (elapsed_ticks > UINT32_MAX-(300*1000)) {
     /* Either about 48 days have passed since the last refill, or the
      * monotonic clock has somehow moved backwards. (We're looking at you,
@@ -132,34 +192,23 @@ token_bucket_refill(token_bucket_t *bucket,
 
   if (!elapsed_steps) {
     /* Note that if less than one whole step elapsed, we don't advance the
-     * time in last_refilled_at_ts. That's intentional: we want to make sure
+     * time in last_refilled_at. That's intentional: we want to make sure
      * that we add some bytes to it eventually. */
     return 0;
   }
 
   int flags = 0;
-  if (refill_single_bucket(&bucket->read_bucket,
-                           bucket->rate, bucket->burst, elapsed_steps))
+  if (token_bucket_raw_refill_steps(&bucket->read_bucket,
+                                    &bucket->cfg, elapsed_steps))
     flags |= TB_READ;
-  if (refill_single_bucket(&bucket->write_bucket,
-                           bucket->rate, bucket->burst, elapsed_steps))
+  if (token_bucket_raw_refill_steps(&bucket->write_bucket,
+                                    &bucket->cfg, elapsed_steps))
     flags |= TB_WRITE;
 
-  bucket->last_refilled_at_ts = now_ts;
+  bucket->last_refilled_at_timestamp = now_ts;
   return flags;
 }
 
-static int
-decrement_single_bucket(int32_t *bucketptr,
-                        ssize_t n)
-{
-  if (BUG(n < 0))
-    return 0;
-  const int becomes_empty = *bucketptr > 0 && n >= *bucketptr;
-  *bucketptr -= n;
-  return becomes_empty;
-}
-
 /**
  * Decrement the read token bucket in <b>bucket</b> by <b>n</b> bytes.
  *
@@ -167,10 +216,10 @@ decrement_single_bucket(int32_t *bucketptr,
  * otherwise.
  */
 int
-token_bucket_dec_read(token_bucket_t *bucket,
+token_bucket_rw_dec_read(token_bucket_rw_t *bucket,
                       ssize_t n)
 {
-  return decrement_single_bucket(&bucket->read_bucket, n);
+  return token_bucket_raw_dec(&bucket->read_bucket, n);
 }
 
 /**
@@ -180,20 +229,21 @@ token_bucket_dec_read(token_bucket_t *bucket,
  * otherwise.
  */
 int
-token_bucket_dec_write(token_bucket_t *bucket,
+token_bucket_rw_dec_write(token_bucket_rw_t *bucket,
                        ssize_t n)
 {
-  return decrement_single_bucket(&bucket->write_bucket, n);
+  return token_bucket_raw_dec(&bucket->write_bucket, n);
 }
 
 /**
- * As token_bucket_dec_read and token_bucket_dec_write, in a single operation.
+ * As token_bucket_rw_dec_read and token_bucket_rw_dec_write, in a single
+ * operation.
  */
 void
-token_bucket_dec(token_bucket_t *bucket,
-                 ssize_t n_read, ssize_t n_written)
+token_bucket_rw_dec(token_bucket_rw_t *bucket,
+                    ssize_t n_read, ssize_t n_written)
 {
-  token_bucket_dec_read(bucket, n_read);
-  token_bucket_dec_read(bucket, n_written);
+  token_bucket_rw_dec_read(bucket, n_read);
+  token_bucket_rw_dec_write(bucket, n_written);
 }
 

src/common/token_bucket.h

@@ -2,8 +2,8 @@
 /* See LICENSE for licensing information */
 
 /**
- * \file token_bucket.h
- * \brief Headers for token_bucket.c
+ * \file token_bucket_rw.h
+ * \brief Headers for token_bucket_rw.c
  **/
 
 #ifndef TOR_TOKEN_BUCKET_H
@@ -11,55 +11,95 @@
 
 #include "torint.h"
 
-typedef struct token_bucket_t {
+/** Largest allowable burst value for a token buffer. */
+#define TOKEN_BUCKET_MAX_BURST INT32_MAX
+
+/** A generic token buffer configuration: determines the number of tokens
+ * added to the bucket in each time unit (the "rate"), and the maximum number
+ * of tokens in the bucket (the "burst") */
+typedef struct token_bucket_cfg_t {
   uint32_t rate;
   int32_t burst;
-  int32_t read_bucket;
-  int32_t write_bucket;
-  uint32_t last_refilled_at_ts;
-} token_bucket_t;
+} token_bucket_cfg_t;
 
-#define TOKEN_BUCKET_MAX_BURST INT32_MAX
+/** A raw token bucket, decoupled from its configuration and timestamp. */
+typedef struct token_bucket_raw_t {
+  int32_t bucket;
+} token_bucket_raw_t;
+
+void token_bucket_cfg_init(token_bucket_cfg_t *cfg,
+                           uint32_t rate,
+                           uint32_t burst);
+
+void token_bucket_raw_adjust(token_bucket_raw_t *bucket,
+                             const token_bucket_cfg_t *cfg);
+
+void token_bucket_raw_reset(token_bucket_raw_t *bucket,
+                            const token_bucket_cfg_t *cfg);
+
+int token_bucket_raw_dec(token_bucket_raw_t *bucket,
+                         ssize_t n);
+
+int token_bucket_raw_refill_steps(token_bucket_raw_t *bucket,
+                                  const token_bucket_cfg_t *cfg,
+                                  const uint32_t elapsed_steps);
+
+static inline size_t token_bucket_raw_get(const token_bucket_raw_t *bucket);
+/** Return the current number of bytes set in a token bucket. */
+static inline size_t
+token_bucket_raw_get(const token_bucket_raw_t *bucket)
+{
+  return bucket->bucket >= 0 ? bucket->bucket : 0;
+}
 
-void token_bucket_init(token_bucket_t *bucket,
+/** A convenience type containing all the pieces needed for a coupled
+ * read-bucket and write-bucket that have the same rate limit, and which use
+ * "timestamp units" (see compat_time.h) for their time. */
+typedef struct token_bucket_rw_t {
+  token_bucket_cfg_t cfg;
+  token_bucket_raw_t read_bucket;
+  token_bucket_raw_t write_bucket;
+  uint32_t last_refilled_at_timestamp;
+} token_bucket_rw_t;
+
+void token_bucket_rw_init(token_bucket_rw_t *bucket,
                        uint32_t rate,
                        uint32_t burst,
                        uint32_t now_ts);
 
-void token_bucket_adjust(token_bucket_t *bucket,
+void token_bucket_rw_adjust(token_bucket_rw_t *bucket,
                          uint32_t rate, uint32_t burst);
 
-void token_bucket_reset(token_bucket_t *bucket,
+void token_bucket_rw_reset(token_bucket_rw_t *bucket,
                         uint32_t now_ts);
 
 #define TB_READ 1
 #define TB_WRITE 2
 
-int token_bucket_refill(token_bucket_t *bucket,
+int token_bucket_rw_refill(token_bucket_rw_t *bucket,
                         uint32_t now_ts);
 
-int token_bucket_dec_read(token_bucket_t *bucket,
+int token_bucket_rw_dec_read(token_bucket_rw_t *bucket,
                           ssize_t n);
-int token_bucket_dec_write(token_bucket_t *bucket,
+int token_bucket_rw_dec_write(token_bucket_rw_t *bucket,
                            ssize_t n);
 
-void token_bucket_dec(token_bucket_t *bucket,
+void token_bucket_rw_dec(token_bucket_rw_t *bucket,
                       ssize_t n_read, ssize_t n_written);
 
-static inline size_t token_bucket_get_read(const token_bucket_t *bucket);
+static inline size_t token_bucket_rw_get_read(const token_bucket_rw_t *bucket);
 static inline size_t
-token_bucket_get_read(const token_bucket_t *bucket)
+token_bucket_rw_get_read(const token_bucket_rw_t *bucket)
 {
-  const ssize_t b = bucket->read_bucket;
-  return b >= 0 ? b : 0;
+  return token_bucket_raw_get(&bucket->read_bucket);
 }
 
-static inline size_t token_bucket_get_write(const token_bucket_t *bucket);
+static inline size_t token_bucket_rw_get_write(
+                                            const token_bucket_rw_t *bucket);
 static inline size_t
-token_bucket_get_write(const token_bucket_t *bucket)
+token_bucket_rw_get_write(const token_bucket_rw_t *bucket)
 {
-  const ssize_t b = bucket->write_bucket;
-  return b >= 0 ? b : 0;
+  return token_bucket_raw_get(&bucket->write_bucket);
 }
 
 #ifdef TOKEN_BUCKET_PRIVATE

src/or/connection.c

@@ -2880,12 +2880,12 @@ connection_bucket_read_limit(connection_t *conn, time_t now)
   int base = RELAY_PAYLOAD_SIZE;
   int priority = conn->type != CONN_TYPE_DIR;
   ssize_t conn_bucket = -1;
-  size_t global_bucket_val = token_bucket_get_read(&global_bucket);
+  size_t global_bucket_val = token_bucket_rw_get_read(&global_bucket);
 
   if (connection_speaks_cells(conn)) {
     or_connection_t *or_conn = TO_OR_CONN(conn);
     if (conn->state == OR_CONN_STATE_OPEN)
-      conn_bucket = token_bucket_get_read(&or_conn->bucket);
+      conn_bucket = token_bucket_rw_get_read(&or_conn->bucket);
     base = get_cell_network_size(or_conn->wide_circ_ids);
   }
 
@@ -2895,7 +2895,7 @@ connection_bucket_read_limit(connection_t *conn, time_t now)
   }
 
   if (connection_counts_as_relayed_traffic(conn, now)) {
-    size_t relayed = token_bucket_get_read(&global_relayed_bucket);
+    size_t relayed = token_bucket_rw_get_read(&global_relayed_bucket);
     global_bucket_val = MIN(global_bucket_val, relayed);
   }
 
@@ -2910,7 +2910,7 @@ connection_bucket_write_limit(connection_t *conn, time_t now)
   int base = RELAY_PAYLOAD_SIZE;
   int priority = conn->type != CONN_TYPE_DIR;
   size_t conn_bucket = conn->outbuf_flushlen;
-  size_t global_bucket_val = token_bucket_get_write(&global_bucket);
+  size_t global_bucket_val = token_bucket_rw_get_write(&global_bucket);
 
   if (!connection_is_rate_limited(conn)) {
     /* be willing to write to local conns even if our buckets are empty */
@@ -2921,12 +2921,13 @@ connection_bucket_write_limit(connection_t *conn, time_t now)
     /* use the per-conn write limit if it's lower */
     or_connection_t *or_conn = TO_OR_CONN(conn);
     if (conn->state == OR_CONN_STATE_OPEN)
-      conn_bucket = MIN(conn_bucket, token_bucket_get_write(&or_conn->bucket));
+      conn_bucket = MIN(conn_bucket,
+                        token_bucket_rw_get_write(&or_conn->bucket));
     base = get_cell_network_size(or_conn->wide_circ_ids);
   }
 
   if (connection_counts_as_relayed_traffic(conn, now)) {
-    size_t relayed = token_bucket_get_write(&global_relayed_bucket);
+    size_t relayed = token_bucket_rw_get_write(&global_relayed_bucket);
     global_bucket_val = MIN(global_bucket_val, relayed);
   }
 
@@ -2956,8 +2957,9 @@ connection_bucket_write_limit(connection_t *conn, time_t now)
 int
 global_write_bucket_low(connection_t *conn, size_t attempt, int priority)
 {
-  size_t smaller_bucket = MIN(token_bucket_get_write(&global_bucket),
-                              token_bucket_get_write(&global_relayed_bucket));
+  size_t smaller_bucket =
+    MIN(token_bucket_rw_get_write(&global_bucket),
+        token_bucket_rw_get_write(&global_relayed_bucket));
   if (authdir_mode(get_options()) && priority>1)
     return 0; /* there's always room to answer v2 if we're an auth dir */
 
@@ -3041,12 +3043,12 @@ connection_buckets_decrement(connection_t *conn, time_t now,
     return; /* local IPs are free */
 
   if (connection_counts_as_relayed_traffic(conn, now)) {
-    token_bucket_dec(&global_relayed_bucket, num_read, num_written);
+    token_bucket_rw_dec(&global_relayed_bucket, num_read, num_written);
   }
-  token_bucket_dec(&global_bucket, num_read, num_written);
+  token_bucket_rw_dec(&global_bucket, num_read, num_written);
   if (connection_speaks_cells(conn) && conn->state == OR_CONN_STATE_OPEN) {
     or_connection_t *or_conn = TO_OR_CONN(conn);
-    token_bucket_dec(&or_conn->bucket, num_read, num_written);
+    token_bucket_rw_dec(&or_conn->bucket, num_read, num_written);
   }
 }
 
@@ -3060,14 +3062,14 @@ connection_consider_empty_read_buckets(connection_t *conn)
   if (!connection_is_rate_limited(conn))
     return; /* Always okay. */
 
-  if (token_bucket_get_read(&global_bucket) <= 0) {
+  if (token_bucket_rw_get_read(&global_bucket) <= 0) {
     reason = "global read bucket exhausted. Pausing.";
   } else if (connection_counts_as_relayed_traffic(conn, approx_time()) &&
-             token_bucket_get_read(&global_relayed_bucket) <= 0) {
+             token_bucket_rw_get_read(&global_relayed_bucket) <= 0) {
     reason = "global relayed read bucket exhausted. Pausing.";
   } else if (connection_speaks_cells(conn) &&
              conn->state == OR_CONN_STATE_OPEN &&
-             token_bucket_get_read(&TO_OR_CONN(conn)->bucket) <= 0) {
+             token_bucket_rw_get_read(&TO_OR_CONN(conn)->bucket) <= 0) {
     reason = "connection read bucket exhausted. Pausing.";
   } else
     return; /* all good, no need to stop it */
@@ -3087,14 +3089,14 @@ connection_consider_empty_write_buckets(connection_t *conn)
   if (!connection_is_rate_limited(conn))
     return; /* Always okay. */
 
-  if (token_bucket_get_write(&global_bucket) <= 0) {
+  if (token_bucket_rw_get_write(&global_bucket) <= 0) {
     reason = "global write bucket exhausted. Pausing.";
   } else if (connection_counts_as_relayed_traffic(conn, approx_time()) &&
-             token_bucket_get_write(&global_relayed_bucket) <= 0) {
+             token_bucket_rw_get_write(&global_relayed_bucket) <= 0) {
     reason = "global relayed write bucket exhausted. Pausing.";
   } else if (connection_speaks_cells(conn) &&
              conn->state == OR_CONN_STATE_OPEN &&
-             token_bucket_get_write(&TO_OR_CONN(conn)->bucket) <= 0) {
+             token_bucket_rw_get_write(&TO_OR_CONN(conn)->bucket) <= 0) {
     reason = "connection write bucket exhausted. Pausing.";
   } else
     return; /* all good, no need to stop it */
@@ -3111,17 +3113,17 @@ connection_bucket_init(void)
 {
   const or_options_t *options = get_options();
   const uint32_t now_ts = monotime_coarse_get_stamp();
-  token_bucket_init(&global_bucket,
+  token_bucket_rw_init(&global_bucket,
                     (int32_t)options->BandwidthRate,
                     (int32_t)options->BandwidthBurst,
                     now_ts);
   if (options->RelayBandwidthRate) {
-    token_bucket_init(&global_relayed_bucket,
+    token_bucket_rw_init(&global_relayed_bucket,
                       (int32_t)options->RelayBandwidthRate,
                       (int32_t)options->RelayBandwidthBurst,
                       now_ts);
   } else {
-    token_bucket_init(&global_relayed_bucket,
+    token_bucket_rw_init(&global_relayed_bucket,
                       (int32_t)options->BandwidthRate,
                       (int32_t)options->BandwidthBurst,
                       now_ts);
@@ -3132,15 +3134,15 @@ connection_bucket_init(void)
 void
 connection_bucket_adjust(const or_options_t *options)
 {
-  token_bucket_adjust(&global_bucket,
+  token_bucket_rw_adjust(&global_bucket,
                       (int32_t)options->BandwidthRate,
                       (int32_t)options->BandwidthBurst);
   if (options->RelayBandwidthRate) {
-    token_bucket_adjust(&global_relayed_bucket,
+    token_bucket_rw_adjust(&global_relayed_bucket,
                         (int32_t)options->RelayBandwidthRate,
                         (int32_t)options->RelayBandwidthBurst);
   } else {
-    token_bucket_adjust(&global_relayed_bucket,
+    token_bucket_rw_adjust(&global_relayed_bucket,
                         (int32_t)options->BandwidthRate,
                         (int32_t)options->BandwidthBurst);
   }
@@ -3153,12 +3155,12 @@ connection_bucket_refill(time_t now, uint32_t now_ts)
   smartlist_t *conns = get_connection_array();
 
   write_buckets_empty_last_second =
-    token_bucket_get_write(&global_bucket) <= 0 ||
-    token_bucket_get_write(&global_relayed_bucket) <= 0;
+    token_bucket_rw_get_write(&global_bucket) <= 0 ||
+    token_bucket_rw_get_write(&global_relayed_bucket) <= 0;
 
   /* refill the global buckets */
-  token_bucket_refill(&global_bucket, now_ts);
-  token_bucket_refill(&global_relayed_bucket, now_ts);
+  token_bucket_rw_refill(&global_bucket, now_ts);
+  token_bucket_rw_refill(&global_relayed_bucket, now_ts);
 
   /* refill the per-connection buckets */
   SMARTLIST_FOREACH_BEGIN(conns, connection_t *, conn) {
@@ -3166,17 +3168,17 @@ connection_bucket_refill(time_t now, uint32_t now_ts)
       or_connection_t *or_conn = TO_OR_CONN(conn);
 
       if (conn->state == OR_CONN_STATE_OPEN) {
-        token_bucket_refill(&or_conn->bucket, now_ts);
+        token_bucket_rw_refill(&or_conn->bucket, now_ts);
       }
     }
 
     if (conn->read_blocked_on_bw == 1 /* marked to turn reading back on now */
-        && token_bucket_get_read(&global_bucket) > 0 /* and we can read */
+        && token_bucket_rw_get_read(&global_bucket) > 0 /* and we can read */
         && (!connection_counts_as_relayed_traffic(conn, now) ||
-            token_bucket_get_read(&global_relayed_bucket) > 0)
+            token_bucket_rw_get_read(&global_relayed_bucket) > 0)
         && (!connection_speaks_cells(conn) ||
             conn->state != OR_CONN_STATE_OPEN ||
-            token_bucket_get_read(&TO_OR_CONN(conn)->bucket) > 0)) {
+            token_bucket_rw_get_read(&TO_OR_CONN(conn)->bucket) > 0)) {
         /* and either a non-cell conn or a cell conn with non-empty bucket */
       LOG_FN_CONN(conn, (LOG_DEBUG,LD_NET,
                          "waking up conn (fd %d) for read", (int)conn->s));
@@ -3185,12 +3187,12 @@ connection_bucket_refill(time_t now, uint32_t now_ts)
     }
 
     if (conn->write_blocked_on_bw == 1
-        && token_bucket_get_write(&global_bucket) > 0 /* and we can write */
+        && token_bucket_rw_get_write(&global_bucket) > 0 /* and we can write */
         && (!connection_counts_as_relayed_traffic(conn, now) ||
-            token_bucket_get_write(&global_relayed_bucket) > 0)
+            token_bucket_rw_get_write(&global_relayed_bucket) > 0)
         && (!connection_speaks_cells(conn) ||
             conn->state != OR_CONN_STATE_OPEN ||
-            token_bucket_get_write(&TO_OR_CONN(conn)->bucket) > 0)) {
+            token_bucket_rw_get_write(&TO_OR_CONN(conn)->bucket) > 0)) {
       LOG_FN_CONN(conn, (LOG_DEBUG,LD_NET,
                          "waking up conn (fd %d) for write", (int)conn->s));
       conn->write_blocked_on_bw = 0;

src/or/connection_or.c

@@ -793,9 +793,9 @@ connection_or_update_token_buckets_helper(or_connection_t *conn, int reset,
                                 (int)options->BandwidthBurst, 1, INT32_MAX);
   }
 
-  token_bucket_adjust(&conn->bucket, rate, burst);
+  token_bucket_rw_adjust(&conn->bucket, rate, burst);
   if (reset) {
-    token_bucket_reset(&conn->bucket, monotime_coarse_get_stamp());
+    token_bucket_rw_reset(&conn->bucket, monotime_coarse_get_stamp());
   }
 }
 

src/or/main.c

@@ -154,10 +154,10 @@ static void shutdown_did_not_work_callback(evutil_socket_t fd, short event,
 /********* START VARIABLES **********/
 
 /* Token bucket for all traffic. */
-token_bucket_t global_bucket;
+token_bucket_rw_t global_bucket;
 
 /* Token bucket for relayed traffic. */
-token_bucket_t global_relayed_bucket;
+token_bucket_rw_t global_relayed_bucket;
 
 /** What was the read/write bucket before the last second_elapsed_callback()
  * call?  (used to determine how many bytes we've read). */
@@ -2394,9 +2394,9 @@ refill_callback(periodic_timer_t *timer, void *arg)
   }
 
   bytes_written = stats_prev_global_write_bucket -
-    token_bucket_get_write(&global_bucket);
+    token_bucket_rw_get_write(&global_bucket);
   bytes_read = stats_prev_global_read_bucket -
-    token_bucket_get_read(&global_bucket);
+    token_bucket_rw_get_read(&global_bucket);
 
   stats_n_bytes_read += bytes_read;
   stats_n_bytes_written += bytes_written;
@@ -2408,8 +2408,8 @@ refill_callback(periodic_timer_t *timer, void *arg)
                              monotime_coarse_get_stamp());
   }
 
-  stats_prev_global_read_bucket = token_bucket_get_read(&global_bucket);
-  stats_prev_global_write_bucket = token_bucket_get_write(&global_bucket);
+  stats_prev_global_read_bucket = token_bucket_rw_get_read(&global_bucket);
+  stats_prev_global_write_bucket = token_bucket_rw_get_write(&global_bucket);
 
   /* remember what time it is, for next time */
   refill_timer_current_millisecond = now;
@@ -2618,8 +2618,8 @@ do_main_loop(void)
 
   /* Set up our buckets */
   connection_bucket_init();
-  stats_prev_global_read_bucket = token_bucket_get_read(&global_bucket);
-  stats_prev_global_write_bucket = token_bucket_get_write(&global_bucket);
+  stats_prev_global_read_bucket = token_bucket_rw_get_read(&global_bucket);
+  stats_prev_global_write_bucket = token_bucket_rw_get_write(&global_bucket);
 
   /* initialize the bootstrap status events to know we're starting up */
   control_event_bootstrap(BOOTSTRAP_STATUS_STARTING, 0);

src/or/main.h

@@ -88,8 +88,8 @@ uint64_t get_main_loop_idle_count(void);
 
 extern time_t time_of_process_start;
 extern int quiet_level;
-extern token_bucket_t global_bucket;
-extern token_bucket_t global_relayed_bucket;
+extern token_bucket_rw_t global_bucket;
+extern token_bucket_rw_t global_relayed_bucket;
 
 #ifdef MAIN_PRIVATE
 STATIC void init_connection_lists(void);

src/or/or.h

@@ -1661,7 +1661,7 @@ typedef struct or_connection_t {
 
   time_t timestamp_lastempty; /**< When was the outbuf last completely empty?*/
 
-  token_bucket_t bucket; /**< Used for rate limiting when the connection is
+  token_bucket_rw_t bucket; /**< Used for rate limiting when the connection is
                           * in state CONN_OPEN. */
 
   /*

src/test/test_bwmgt.c

@@ -21,23 +21,23 @@ static void
 test_bwmgt_token_buf_init(void *arg)
 {
   (void)arg;
-  token_bucket_t b;
+  token_bucket_rw_t b;
 
-  token_bucket_init(&b, 16*KB, 64*KB, START_TS);
+  token_bucket_rw_init(&b, 16*KB, 64*KB, START_TS);
   // Burst is correct
-  tt_uint_op(b.burst, OP_EQ, 64*KB);
+  tt_uint_op(b.cfg.burst, OP_EQ, 64*KB);
   // Rate is correct, within 1 percent.
   {
     uint32_t ticks_per_sec =
       (uint32_t) monotime_msec_to_approx_coarse_stamp_units(1000);
-    uint32_t rate_per_sec = (b.rate * ticks_per_sec / TICKS_PER_STEP);
+    uint32_t rate_per_sec = (b.cfg.rate * ticks_per_sec / TICKS_PER_STEP);
 
     tt_uint_op(rate_per_sec, OP_GT, 16*KB-160);
     tt_uint_op(rate_per_sec, OP_LT, 16*KB+160);
   }
   // Bucket starts out full:
-  tt_uint_op(b.last_refilled_at_ts, OP_EQ, START_TS);
-  tt_int_op(b.read_bucket, OP_EQ, 64*KB);
+  tt_uint_op(b.last_refilled_at_timestamp, OP_EQ, START_TS);
+  tt_int_op(b.read_bucket.bucket, OP_EQ, 64*KB);
 
  done:
   ;
@@ -47,35 +47,35 @@ static void
 test_bwmgt_token_buf_adjust(void *arg)
 {
   (void)arg;
-  token_bucket_t b;
+  token_bucket_rw_t b;
 
-  token_bucket_init(&b, 16*KB, 64*KB, START_TS);
+  token_bucket_rw_init(&b, 16*KB, 64*KB, START_TS);
 
-  uint32_t rate_orig = b.rate;
+  uint32_t rate_orig = b.cfg.rate;
   // Increasing burst
-  token_bucket_adjust(&b, 16*KB, 128*KB);
-  tt_uint_op(b.rate, OP_EQ, rate_orig);
-  tt_uint_op(b.read_bucket, OP_EQ, 64*KB);
-  tt_uint_op(b.burst, OP_EQ, 128*KB);
+  token_bucket_rw_adjust(&b, 16*KB, 128*KB);
+  tt_uint_op(b.cfg.rate, OP_EQ, rate_orig);
+  tt_uint_op(b.read_bucket.bucket, OP_EQ, 64*KB);
+  tt_uint_op(b.cfg.burst, OP_EQ, 128*KB);
 
   // Decreasing burst but staying above bucket
-  token_bucket_adjust(&b, 16*KB, 96*KB);
-  tt_uint_op(b.rate, OP_EQ, rate_orig);
-  tt_uint_op(b.read_bucket, OP_EQ, 64*KB);
-  tt_uint_op(b.burst, OP_EQ, 96*KB);
+  token_bucket_rw_adjust(&b, 16*KB, 96*KB);
+  tt_uint_op(b.cfg.rate, OP_EQ, rate_orig);
+  tt_uint_op(b.read_bucket.bucket, OP_EQ, 64*KB);
+  tt_uint_op(b.cfg.burst, OP_EQ, 96*KB);
 
   // Decreasing burst below bucket,
-  token_bucket_adjust(&b, 16*KB, 48*KB);
-  tt_uint_op(b.rate, OP_EQ, rate_orig);
-  tt_uint_op(b.read_bucket, OP_EQ, 48*KB);
-  tt_uint_op(b.burst, OP_EQ, 48*KB);
+  token_bucket_rw_adjust(&b, 16*KB, 48*KB);
+  tt_uint_op(b.cfg.rate, OP_EQ, rate_orig);
+  tt_uint_op(b.read_bucket.bucket, OP_EQ, 48*KB);
+  tt_uint_op(b.cfg.burst, OP_EQ, 48*KB);
 
   // Changing rate.
-  token_bucket_adjust(&b, 32*KB, 48*KB);
-  tt_uint_op(b.rate, OP_GE, rate_orig*2 - 10);
-  tt_uint_op(b.rate, OP_LE, rate_orig*2 + 10);
-  tt_uint_op(b.read_bucket, OP_EQ, 48*KB);
-  tt_uint_op(b.burst, OP_EQ, 48*KB);
+  token_bucket_rw_adjust(&b, 32*KB, 48*KB);
+  tt_uint_op(b.cfg.rate, OP_GE, rate_orig*2 - 10);
+  tt_uint_op(b.cfg.rate, OP_LE, rate_orig*2 + 10);
+  tt_uint_op(b.read_bucket.bucket, OP_EQ, 48*KB);
+  tt_uint_op(b.cfg.burst, OP_EQ, 48*KB);
 
  done:
   ;
@@ -85,34 +85,34 @@ static void
 test_bwmgt_token_buf_dec(void *arg)
 {
   (void)arg;
-  token_bucket_t b;
-  token_bucket_init(&b, 16*KB, 64*KB, START_TS);
+  token_bucket_rw_t b;
+  token_bucket_rw_init(&b, 16*KB, 64*KB, START_TS);
 
   // full-to-not-full.
-  tt_int_op(0, OP_EQ, token_bucket_dec_read(&b, KB));
-  tt_int_op(b.read_bucket, OP_EQ, 63*KB);
+  tt_int_op(0, OP_EQ, token_bucket_rw_dec_read(&b, KB));
+  tt_int_op(b.read_bucket.bucket, OP_EQ, 63*KB);
 
   // Full to almost-not-full
-  tt_int_op(0, OP_EQ, token_bucket_dec_read(&b, 63*KB - 1));
-  tt_int_op(b.read_bucket, OP_EQ, 1);
+  tt_int_op(0, OP_EQ, token_bucket_rw_dec_read(&b, 63*KB - 1));
+  tt_int_op(b.read_bucket.bucket, OP_EQ, 1);
 
   // almost-not-full to empty.
-  tt_int_op(1, OP_EQ, token_bucket_dec_read(&b, 1));
-  tt_int_op(b.read_bucket, OP_EQ, 0);
+  tt_int_op(1, OP_EQ, token_bucket_rw_dec_read(&b, 1));
+  tt_int_op(b.read_bucket.bucket, OP_EQ, 0);
 
   // reset bucket, try full-to-empty
-  token_bucket_init(&b, 16*KB, 64*KB, START_TS);
-  tt_int_op(1, OP_EQ, token_bucket_dec_read(&b, 64*KB));
-  tt_int_op(b.read_bucket, OP_EQ, 0);
+  token_bucket_rw_init(&b, 16*KB, 64*KB, START_TS);
+  tt_int_op(1, OP_EQ, token_bucket_rw_dec_read(&b, 64*KB));
+  tt_int_op(b.read_bucket.bucket, OP_EQ, 0);
 
   // reset bucket, try underflow.
-  token_bucket_init(&b, 16*KB, 64*KB, START_TS);
-  tt_int_op(1, OP_EQ, token_bucket_dec_read(&b, 64*KB + 1));
-  tt_int_op(b.read_bucket, OP_EQ, -1);
+  token_bucket_rw_init(&b, 16*KB, 64*KB, START_TS);
+  tt_int_op(1, OP_EQ, token_bucket_rw_dec_read(&b, 64*KB + 1));
+  tt_int_op(b.read_bucket.bucket, OP_EQ, -1);
 
   // A second underflow does not make the bucket empty.
-  tt_int_op(0, OP_EQ, token_bucket_dec_read(&b, 1000));
-  tt_int_op(b.read_bucket, OP_EQ, -1001);
+  tt_int_op(0, OP_EQ, token_bucket_rw_dec_read(&b, 1000));
+  tt_int_op(b.read_bucket.bucket, OP_EQ, -1001);
 
  done:
   ;
@@ -122,71 +122,71 @@ static void
 test_bwmgt_token_buf_refill(void *arg)
 {
   (void)arg;
-  token_bucket_t b;
+  token_bucket_rw_t b;
   const uint32_t SEC =
     (uint32_t)monotime_msec_to_approx_coarse_stamp_units(1000);
-  printf("%d\n", (int)SEC);
-  token_bucket_init(&b, 16*KB, 64*KB, START_TS);
+  token_bucket_rw_init(&b, 16*KB, 64*KB, START_TS);
 
   /* Make the buffer much emptier, then let one second elapse. */
-  token_bucket_dec_read(&b, 48*KB);
-  tt_int_op(b.read_bucket, OP_EQ, 16*KB);
-  tt_int_op(0, OP_EQ, token_bucket_refill(&b, START_TS + SEC));
-  tt_int_op(b.read_bucket, OP_GT, 32*KB - 300);
-  tt_int_op(b.read_bucket, OP_LT, 32*KB + 300);
+  token_bucket_rw_dec_read(&b, 48*KB);
+  tt_int_op(b.read_bucket.bucket, OP_EQ, 16*KB);
+  tt_int_op(0, OP_EQ, token_bucket_rw_refill(&b, START_TS + SEC));
+  tt_int_op(b.read_bucket.bucket, OP_GT, 32*KB - 300);
+  tt_int_op(b.read_bucket.bucket, OP_LT, 32*KB + 300);
 
   /* Another half second. */
-  tt_int_op(0, OP_EQ, token_bucket_refill(&b, START_TS + SEC*3/2));
-  tt_int_op(b.read_bucket, OP_GT, 40*KB - 400);
-  tt_int_op(b.read_bucket, OP_LT, 40*KB + 400);
-  tt_uint_op(b.last_refilled_at_ts, OP_EQ, START_TS + SEC*3/2);
+  tt_int_op(0, OP_EQ, token_bucket_rw_refill(&b, START_TS + SEC*3/2));
+  tt_int_op(b.read_bucket.bucket, OP_GT, 40*KB - 400);
+  tt_int_op(b.read_bucket.bucket, OP_LT, 40*KB + 400);
+  tt_uint_op(b.last_refilled_at_timestamp, OP_EQ, START_TS + SEC*3/2);
 
   /* No time: nothing happens. */
   {
-    const uint32_t bucket_orig = b.read_bucket;
-    tt_int_op(0, OP_EQ, token_bucket_refill(&b, START_TS + SEC*3/2));
-    tt_int_op(b.read_bucket, OP_EQ, bucket_orig);
+    const uint32_t bucket_orig = b.read_bucket.bucket;
+    tt_int_op(0, OP_EQ, token_bucket_rw_refill(&b, START_TS + SEC*3/2));
+    tt_int_op(b.read_bucket.bucket, OP_EQ, bucket_orig);
   }
 
   /* Another 30 seconds: fill the bucket. */
-  tt_int_op(0, OP_EQ, token_bucket_refill(&b, START_TS + SEC*3/2 + SEC*30));
-  tt_int_op(b.read_bucket, OP_EQ, b.burst);
-  tt_uint_op(b.last_refilled_at_ts, OP_EQ, START_TS + SEC*3/2 + SEC*30);
+  tt_int_op(0, OP_EQ, token_bucket_rw_refill(&b, START_TS + SEC*3/2 + SEC*30));
+  tt_int_op(b.read_bucket.bucket, OP_EQ, b.cfg.burst);
+  tt_uint_op(b.last_refilled_at_timestamp, OP_EQ, START_TS + SEC*3/2 + SEC*30);
 
   /* Another 30 seconds: nothing happens. */
-  tt_int_op(0, OP_EQ, token_bucket_refill(&b, START_TS + SEC*3/2 + SEC*60));
-  tt_int_op(b.read_bucket, OP_EQ, b.burst);
-  tt_uint_op(b.last_refilled_at_ts, OP_EQ, START_TS + SEC*3/2 + SEC*60);
+  tt_int_op(0, OP_EQ, token_bucket_rw_refill(&b, START_TS + SEC*3/2 + SEC*60));
+  tt_int_op(b.read_bucket.bucket, OP_EQ, b.cfg.burst);
+  tt_uint_op(b.last_refilled_at_timestamp, OP_EQ, START_TS + SEC*3/2 + SEC*60);
 
   /* Empty the bucket, let two seconds pass, and make sure that a refill is
    * noticed. */
-  tt_int_op(1, OP_EQ, token_bucket_dec_read(&b, b.burst));
-  tt_int_op(0, OP_EQ, b.read_bucket);
-  tt_int_op(1, OP_EQ, token_bucket_refill(&b, START_TS + SEC*3/2 + SEC*61));
-  tt_int_op(0, OP_EQ, token_bucket_refill(&b, START_TS + SEC*3/2 + SEC*62));
-  tt_int_op(b.read_bucket, OP_GT, 32*KB-400);
-  tt_int_op(b.read_bucket, OP_LT, 32*KB+400);
+  tt_int_op(1, OP_EQ, token_bucket_rw_dec_read(&b, b.cfg.burst));
+  tt_int_op(0, OP_EQ, b.read_bucket.bucket);
+  tt_int_op(1, OP_EQ, token_bucket_rw_refill(&b, START_TS + SEC*3/2 + SEC*61));
+  tt_int_op(0, OP_EQ, token_bucket_rw_refill(&b, START_TS + SEC*3/2 + SEC*62));
+  tt_int_op(b.read_bucket.bucket, OP_GT, 32*KB-400);
+  tt_int_op(b.read_bucket.bucket, OP_LT, 32*KB+400);
 
   /* Underflow the bucket, make sure we detect when it has tokens again. */
-  tt_int_op(1, OP_EQ, token_bucket_dec_read(&b, b.read_bucket+16*KB));
-  tt_int_op(-16*KB, OP_EQ, b.read_bucket);
+  tt_int_op(1, OP_EQ,
+            token_bucket_rw_dec_read(&b, b.read_bucket.bucket+16*KB));
+  tt_int_op(-16*KB, OP_EQ, b.read_bucket.bucket);
   // half a second passes...
-  tt_int_op(0, OP_EQ, token_bucket_refill(&b, START_TS + SEC*64));
-  tt_int_op(b.read_bucket, OP_GT, -8*KB-300);
-  tt_int_op(b.read_bucket, OP_LT, -8*KB+300);
+  tt_int_op(0, OP_EQ, token_bucket_rw_refill(&b, START_TS + SEC*64));
+  tt_int_op(b.read_bucket.bucket, OP_GT, -8*KB-300);
+  tt_int_op(b.read_bucket.bucket, OP_LT, -8*KB+300);
   // a second passes
-  tt_int_op(1, OP_EQ, token_bucket_refill(&b, START_TS + SEC*65));
-  tt_int_op(b.read_bucket, OP_GT, 8*KB-400);
-  tt_int_op(b.read_bucket, OP_LT, 8*KB+400);
+  tt_int_op(1, OP_EQ, token_bucket_rw_refill(&b, START_TS + SEC*65));
+  tt_int_op(b.read_bucket.bucket, OP_GT, 8*KB-400);
+  tt_int_op(b.read_bucket.bucket, OP_LT, 8*KB+400);
 
   // We step a second backwards, and nothing happens.
-  tt_int_op(0, OP_EQ, token_bucket_refill(&b, START_TS + SEC*64));
-  tt_int_op(b.read_bucket, OP_GT, 8*KB-400);
-  tt_int_op(b.read_bucket, OP_LT, 8*KB+400);
+  tt_int_op(0, OP_EQ, token_bucket_rw_refill(&b, START_TS + SEC*64));
+  tt_int_op(b.read_bucket.bucket, OP_GT, 8*KB-400);
+  tt_int_op(b.read_bucket.bucket, OP_LT, 8*KB+400);
 
   // A ridiculous amount of time passes.
-  tt_int_op(0, OP_EQ, token_bucket_refill(&b, INT32_MAX));
-  tt_int_op(b.read_bucket, OP_EQ, b.burst);
+  tt_int_op(0, OP_EQ, token_bucket_rw_refill(&b, INT32_MAX));
+  tt_int_op(b.read_bucket.bucket, OP_EQ, b.cfg.burst);
 
  done:
   ;