[tor-commits] [tor/master] Refactor "timestamp" not to be its own type coupled to token buffers

[nickm at torproject.org]

commit 003e6595bf355fd13f85eb31e7850cec086ecd07
Author: Nick Mathewson <nickm at torproject.org>
Date:   Fri Apr 13 12:03:29 2018 -0400

    Refactor "timestamp" not to be its own type coupled to token buffers
    
    Really, the uint32_t is only an optimization; any kind of unit
    should work fine.  Some users might want to use time_t or
    monotime_coarse_t or something like that.
---
 src/common/token_bucket.c | 19 ++++++++-----------
 src/common/token_bucket.h | 12 ++----------
 src/test/test_bwmgt.c     |  8 ++++----
 3 files changed, 14 insertions(+), 25 deletions(-)

diff --git a/src/common/token_bucket.c b/src/common/token_bucket.c
index 8be377599..7c81264e2 100644
--- a/src/common/token_bucket.c
+++ b/src/common/token_bucket.c
@@ -48,12 +48,9 @@ token_bucket_cfg_init(token_bucket_cfg_t *cfg,
  */
 void
 token_bucket_raw_reset(token_bucket_raw_t *bucket,
-                       token_bucket_timestamp_t *stamp,
-                       const token_bucket_cfg_t *cfg,
-                       uint32_t now)
+                       const token_bucket_cfg_t *cfg)
 {
   bucket->bucket = cfg->burst;
-  stamp->last_refilled_at = now;
 }
 
 /**
@@ -165,10 +162,9 @@ void
 token_bucket_rw_reset(token_bucket_rw_t *bucket,
                       uint32_t now_ts)
 {
-  token_bucket_raw_reset(&bucket->read_bucket, &bucket->stamp,
-                         &bucket->cfg, now_ts);
-  token_bucket_raw_reset(&bucket->write_bucket, &bucket->stamp,
-                         &bucket->cfg, now_ts);
+  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;
 }
 
 /**
@@ -180,9 +176,10 @@ token_bucket_rw_reset(token_bucket_rw_t *bucket,
  */
 int
 token_bucket_rw_refill(token_bucket_rw_t *bucket,
-                    uint32_t now_ts)
+                       uint32_t now_ts)
 {
-  const uint32_t elapsed_ticks = (now_ts - bucket->stamp.last_refilled_at);
+  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,
@@ -208,7 +205,7 @@ token_bucket_rw_refill(token_bucket_rw_t *bucket,
                                     &bucket->cfg, elapsed_steps))
     flags |= TB_WRITE;
 
-  bucket->stamp.last_refilled_at = now_ts;
+  bucket->last_refilled_at_timestamp = now_ts;
   return flags;
 }
 
diff --git a/src/common/token_bucket.h b/src/common/token_bucket.h
index 2507cd225..44315fb6b 100644
--- a/src/common/token_bucket.h
+++ b/src/common/token_bucket.h
@@ -27,12 +27,6 @@ typedef struct token_bucket_raw_t {
   int32_t bucket;
 } token_bucket_raw_t;
 
-/** A timestamp for a token bucket. The units of this timestamp are
- * unspecified, but must match with the rate set in the token_bucket_cfg_t. */
-typedef struct token_bucket_timestamp_t {
-  uint32_t last_refilled_at;
-} token_bucket_timestamp_t;
-
 void token_bucket_cfg_init(token_bucket_cfg_t *cfg,
                            uint32_t rate,
                            uint32_t burst);
@@ -41,9 +35,7 @@ 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,
-                            token_bucket_timestamp_t *stamp,
-                            const token_bucket_cfg_t *cfg,
-                            uint32_t now);
+                            const token_bucket_cfg_t *cfg);
 
 int token_bucket_raw_dec(token_bucket_raw_t *bucket,
                          ssize_t n);
@@ -67,7 +59,7 @@ typedef struct token_bucket_rw_t {
   token_bucket_cfg_t cfg;
   token_bucket_raw_t read_bucket;
   token_bucket_raw_t write_bucket;
-  token_bucket_timestamp_t stamp;
+  uint32_t last_refilled_at_timestamp;
 } token_bucket_rw_t;
 
 void token_bucket_rw_init(token_bucket_rw_t *bucket,
diff --git a/src/test/test_bwmgt.c b/src/test/test_bwmgt.c
index 17914aeb9..003671a42 100644
--- a/src/test/test_bwmgt.c
+++ b/src/test/test_bwmgt.c
@@ -36,7 +36,7 @@ test_bwmgt_token_buf_init(void *arg)
     tt_uint_op(rate_per_sec, OP_LT, 16*KB+160);
   }
   // Bucket starts out full:
-  tt_uint_op(b.stamp.last_refilled_at, OP_EQ, START_TS);
+  tt_uint_op(b.last_refilled_at_timestamp, OP_EQ, START_TS);
   tt_int_op(b.read_bucket.bucket, OP_EQ, 64*KB);
 
  done:
@@ -138,7 +138,7 @@ test_bwmgt_token_buf_refill(void *arg)
   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.stamp.last_refilled_at, OP_EQ, START_TS + SEC*3/2);
+  tt_uint_op(b.last_refilled_at_timestamp, OP_EQ, START_TS + SEC*3/2);
 
   /* No time: nothing happens. */
   {
@@ -150,12 +150,12 @@ test_bwmgt_token_buf_refill(void *arg)
   /* Another 30 seconds: fill the bucket. */
   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.stamp.last_refilled_at, OP_EQ, START_TS + SEC*3/2 + SEC*30);
+  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_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.stamp.last_refilled_at, OP_EQ, START_TS + SEC*3/2 + SEC*60);
+  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. */