[or-cvs] [tor/master] Implement queue with O(1) operations, and correct some math.
Nick Mathewson
nickm at seul.org
Wed Aug 26 15:36:43 UTC 2009
Author: Karsten Loesing <karsten.loesing at gmx.net>
Date: Mon, 17 Aug 2009 13:07:56 +0200
Subject: Implement queue with O(1) operations, and correct some math.
Commit: f37af0180d63f59dbb856e897f44a77d0390ab1a
---
src/or/or.h | 18 +++++++++++++++-
src/or/relay.c | 59 +++++++++++++++++++++++++++----------------------------
2 files changed, 45 insertions(+), 32 deletions(-)
diff --git a/src/or/or.h b/src/or/or.h
index ce4fbd0..c9eb4a3 100644
--- a/src/or/or.h
+++ b/src/or/or.h
@@ -835,16 +835,30 @@ typedef struct var_cell_t {
typedef struct packed_cell_t {
struct packed_cell_t *next; /**< Next cell queued on this circuit. */
char body[CELL_NETWORK_SIZE]; /**< Cell as packed for network. */
- struct timeval packed_timeval; /**< When was this cell packed? */
} packed_cell_t;
+/** Number of cells added to a circuit queue including their insertion
+ * time on 10 millisecond detail; used for buffer statistics. */
+typedef struct insertion_time_elem_t {
+ struct insertion_time_elem_t *next;
+ uint32_t insertion_time; /**< When were cells inserted (in 10 ms steps
+ * starting at 0:00 of the current day)? */
+ unsigned counter; /**< How many cells were inserted? */
+} insertion_time_elem_t;
+
+/** Queue of insertion times. */
+typedef struct insertion_time_queue_t {
+ struct insertion_time_elem_t *first;
+ struct insertion_time_elem_t *last;
+} insertion_time_queue_t;
+
/** A queue of cells on a circuit, waiting to be added to the
* or_connection_t's outbuf. */
typedef struct cell_queue_t {
packed_cell_t *head; /**< The first cell, or NULL if the queue is empty. */
packed_cell_t *tail; /**< The last cell, or NULL if the queue is empty. */
int n; /**< The number of cells in the queue. */
- smartlist_t *insertion_times;
+ insertion_time_queue_t *insertion_times;
} cell_queue_t;
/** Beginning of a RELAY cell payload. */
diff --git a/src/or/relay.c b/src/or/relay.c
index 929b2e7..66475b4 100644
--- a/src/or/relay.c
+++ b/src/or/relay.c
@@ -1612,14 +1612,6 @@ cell_queue_append(cell_queue_t *queue, packed_cell_t *cell)
++queue->n;
}
-/** Number of cells added to a circuit queue including their insertion
- * time on 10 millisecond detail; used for buffer statistics. */
-typedef struct insertion_time_elem_t {
- uint32_t insertion_time; /**< When were cells inserted (in 10 ms steps
- * starting at 0:00 of the current day)? */
- unsigned counter; /**< How many cells were inserted? */
-} insertion_time_elem_t;
-
/** Append a newly allocated copy of <b>cell</b> to the end of <b>queue</b> */
void
cell_queue_append_packed_copy(cell_queue_t *queue, const cell_t *cell)
@@ -1629,21 +1621,20 @@ cell_queue_append_packed_copy(cell_queue_t *queue, const cell_t *cell)
if (get_options()->CellStatistics) {
struct timeval now;
uint32_t added;
- insertion_time_elem_t *last_elem = NULL;
+ insertion_time_queue_t *it_queue = queue->insertion_times;
int add_new_elem = 0;
tor_gettimeofday(&now);
#define SECONDS_IN_A_DAY 86400L
- added = now.tv_sec % SECONDS_IN_A_DAY * 10L + now.tv_usec / 100000L;
- if (!queue->insertion_times) {
- queue->insertion_times = smartlist_create();
+ added = (now.tv_sec % SECONDS_IN_A_DAY) * 100L + now.tv_usec / 10000L;
+ if (!it_queue) {
+ it_queue = tor_malloc_zero(sizeof(insertion_time_queue_t));
+ queue->insertion_times = it_queue;
}
- if (smartlist_len(queue->insertion_times) < 1) {
+ if (!it_queue->first) {
add_new_elem = 1;
} else {
- last_elem = smartlist_get(queue->insertion_times,
- smartlist_len(queue->insertion_times) - 1);
- if (last_elem->insertion_time == added)
- last_elem->counter++;
+ if (it_queue->last->insertion_time == added)
+ it_queue->last->counter++;
else
add_new_elem = 1;
}
@@ -1652,7 +1643,12 @@ cell_queue_append_packed_copy(cell_queue_t *queue, const cell_t *cell)
tor_malloc_zero(sizeof(insertion_time_elem_t));
elem->insertion_time = added;
elem->counter = 1;
- smartlist_add(queue->insertion_times, elem);
+ if (it_queue->last) {
+ it_queue->last->next = elem;
+ it_queue->last = elem;
+ } else {
+ it_queue->first = it_queue->last = elem;
+ }
}
}
cell_queue_append(queue, copy);
@@ -1672,8 +1668,11 @@ cell_queue_clear(cell_queue_t *queue)
queue->head = queue->tail = NULL;
queue->n = 0;
if (queue->insertion_times) {
- SMARTLIST_FOREACH(queue->insertion_times, void *, e, tor_free(e));
- smartlist_free(queue->insertion_times);
+ while (queue->insertion_times->first) {
+ insertion_time_elem_t *elem = queue->insertion_times->first;
+ queue->insertion_times->first = elem->next;
+ tor_free(elem);
+ }
queue->insertion_times = NULL;
}
}
@@ -1874,23 +1873,23 @@ connection_or_flush_from_first_active_circuit(or_connection_t *conn, int max,
struct timeval now;
uint32_t flushed;
uint32_t cell_waiting_time;
+ insertion_time_queue_t *it_queue = queue->insertion_times;
tor_gettimeofday(&now);
- flushed = now.tv_sec % SECONDS_IN_A_DAY * 10L + now.tv_usec / 100000L;
- if (!queue->insertion_times ||
- smartlist_len(queue->insertion_times) < 1) {
+ flushed = (now.tv_sec % SECONDS_IN_A_DAY) * 100L +
+ now.tv_usec / 10000L;
+ if (!it_queue || !it_queue->first) {
log_warn(LD_BUG, "Cannot determine insertion time of cell.");
} else {
or_circuit_t *orcirc = TO_OR_CIRCUIT(circ);
- insertion_time_elem_t *elem = smartlist_get(
- queue->insertion_times, 0);
- cell_waiting_time = (flushed + SECONDS_IN_A_DAY * 10L -
- elem->insertion_time) % (SECONDS_IN_A_DAY * 10L);
+ insertion_time_elem_t *elem = it_queue->first;
+ cell_waiting_time = (flushed * 10L + SECONDS_IN_A_DAY * 1000L -
+ elem->insertion_time * 10L) % (SECONDS_IN_A_DAY * 1000L);
#undef SECONDS_IN_A_DAY
elem->counter--;
if (elem->counter < 1) {
-// TODO this operation is really expensive! write own queue impl?
-// smartlist_del(queue->insertion_times, 0);
- smartlist_remove(queue->insertion_times, elem);
+ it_queue->first = elem->next;
+ if (elem == it_queue->last)
+ it_queue->last = NULL;
tor_free(elem);
}
orcirc->total_cell_waiting_time += cell_waiting_time;
--
1.5.6.5
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