*
*
*/
+#if TW_START_STOP_TRACE_SIZE > 0
+
+void TW (tw_timer_trace) (TWT (tw_timer_wheel) * tw, u32 timer_id,
+ u32 pool_index, u32 handle)
+{
+ TWT (trace) * t = &tw->traces[tw->trace_index];
+
+ t->timer_id = timer_id;
+ t->pool_index = pool_index;
+ t->handle = handle;
+
+ tw->trace_index++;
+ if (tw->trace_index == TW_START_STOP_TRACE_SIZE)
+ {
+ tw->trace_index = 0;
+ tw->trace_wrapped++;
+ }
+}
+
+void TW (tw_search_trace) (TWT (tw_timer_wheel) * tw, u32 handle)
+{
+ u32 i, start_pos;
+ TWT (trace) * t;
+ char *s = "bogus!";
+
+ /* reverse search for the supplied handle */
+
+ start_pos = tw->trace_index;
+ if (start_pos == 0)
+ start_pos = TW_START_STOP_TRACE_SIZE - 1;
+ else
+ start_pos--;
+
+ for (i = start_pos; i > 0; i--)
+ {
+ t = &tw->traces[i];
+ if (t->handle == handle)
+ {
+ switch (t->timer_id)
+ {
+ case 0xFF:
+ s = "stopped";
+ break;
+ case 0xFE:
+ s = "expired";
+ break;
+ default:
+ s = "started";
+ break;
+ }
+ fformat (stderr, "handle 0x%x (%d) %s at trace %d\n",
+ handle, handle, s, i);
+ }
+ }
+ if (tw->trace_wrapped > 0)
+ {
+ for (i = TW_START_STOP_TRACE_SIZE; i >= tw->trace_index; i--)
+ {
+ t = &tw->traces[i];
+ if (t->handle == handle)
+ {
+ switch (t->timer_id)
+ {
+ case 0xFF:
+ s = "stopped";
+ break;
+ case 0xFE:
+ s = "expired";
+ break;
+ default:
+ s = "started";
+ break;
+ }
+ fformat (stderr, "handle 0x%x (%d) %s at trace %d\n",
+ handle, handle, s, i);
+ }
+ }
+ }
+}
+#endif /* TW_START_STOP_TRACE_SIZE > 0 */
static inline u32
TW (make_internal_timer_handle) (u32 pool_index, u32 timer_id)
u32 handle;
ASSERT (timer_id < TW_TIMERS_PER_OBJECT);
+#if LOG2_TW_TIMERS_PER_OBJECT > 0
ASSERT (pool_index < (1 << (32 - LOG2_TW_TIMERS_PER_OBJECT)));
handle = (timer_id << (32 - LOG2_TW_TIMERS_PER_OBJECT)) | (pool_index);
+#else
+ handle = pool_index;
+#endif
return handle;
}
}
static inline void
-timer_remove (TWT (tw_timer) * pool, u32 index)
+timer_remove (TWT (tw_timer) * pool, TWT (tw_timer) * elt)
{
- TWT (tw_timer) * elt = pool_elt_at_index (pool, index);
TWT (tw_timer) * next_elt, *prev_elt;
ASSERT (elt->user_handle != ~0);
elt->prev = elt->next = ~0;
}
-/**
- * @brief Start a Tw Timer
- * @param tw_timer_wheel_t * tw timer wheel object pointer
- * @param u32 pool_index user pool index, presumably for a tw session
- * @param u32 timer_id app-specific timer ID. 4 bits.
- * @param u32 interval timer interval in ticks
- * @returns handle needed to cancel the timer
- */
-u32
-TW (tw_timer_start) (TWT (tw_timer_wheel) * tw, u32 pool_index, u32 timer_id,
- u32 interval)
+static inline void
+timer_add (TWT (tw_timer_wheel) * tw, TWT (tw_timer) * t, u64 interval)
{
#if TW_TIMER_WHEELS > 1
u16 slow_ring_offset;
u32 carry;
+#endif
+#if TW_TIMER_WHEELS > 2
+ u16 glacier_ring_offset;
+#endif
+#if TW_OVERFLOW_VECTOR > 0
+ u64 interval_plus_time_to_wrap, triple_wrap_mask;
#endif
u16 fast_ring_offset;
tw_timer_wheel_slot_t *ts;
- TWT (tw_timer) * t;
- ASSERT (interval);
+ /* Factor interval into 1..3 wheel offsets */
+#if TW_TIMER_WHEELS > 2
+#if TW_OVERFLOW_VECTOR > 0
+ /*
+ * This is tricky. Put a timer onto the overflow
+ * vector if the interval PLUS the time
+ * until the next triple-wrap exceeds one full revolution
+ * of all three wheels.
+ */
+ triple_wrap_mask = (1 << (3 * TW_RING_SHIFT)) - 1;
+ interval_plus_time_to_wrap =
+ interval + (tw->current_tick & triple_wrap_mask);
+ if ((interval_plus_time_to_wrap >= 1 << (3 * TW_RING_SHIFT)))
+ {
+ t->expiration_time = tw->current_tick + interval;
+ ts = &tw->overflow;
+ timer_addhead (tw->timers, ts->head_index, t - tw->timers);
+#if TW_START_STOP_TRACE_SIZE > 0
+ TW (tw_timer_trace) (tw, timer_id, user_id, t - tw->timers);
+#endif
+ return;
+ }
+#endif
- pool_get (tw->timers, t);
- t->next = t->prev = ~0;
+ glacier_ring_offset = interval >> (2 * TW_RING_SHIFT);
+ ASSERT ((u64) glacier_ring_offset < TW_SLOTS_PER_RING);
+ interval -= (((u64) glacier_ring_offset) << (2 * TW_RING_SHIFT));
+#endif
#if TW_TIMER_WHEELS > 1
- t->fast_ring_offset = ~0;
+ slow_ring_offset = interval >> TW_RING_SHIFT;
+ ASSERT ((u64) slow_ring_offset < TW_SLOTS_PER_RING);
+ interval -= (((u64) slow_ring_offset) << TW_RING_SHIFT);
#endif
- t->user_handle = TW (make_internal_timer_handle) (pool_index, timer_id);
-
fast_ring_offset = interval & TW_RING_MASK;
- fast_ring_offset += tw->current_index[TW_TIMER_RING_FAST];
+
+ /*
+ * Account for the current wheel positions(s)
+ * This is made slightly complicated by the fact that the current
+ * index vector will contain (TW_SLOTS_PER_RING, ...) when
+ * the actual position is (0, ...)
+ */
+
+ fast_ring_offset += tw->current_index[TW_TIMER_RING_FAST] & TW_RING_MASK;
+
#if TW_TIMER_WHEELS > 1
carry = fast_ring_offset >= TW_SLOTS_PER_RING ? 1 : 0;
fast_ring_offset %= TW_SLOTS_PER_RING;
- slow_ring_offset = (interval >> TW_RING_SHIFT) + carry;
+ slow_ring_offset += (tw->current_index[TW_TIMER_RING_SLOW] & TW_RING_MASK)
+ + carry;
+ carry = slow_ring_offset >= TW_SLOTS_PER_RING ? 1 : 0;
+ slow_ring_offset %= TW_SLOTS_PER_RING;
+#endif
- /* Timer duration exceeds ~7 hrs? Oops */
- ASSERT (slow_ring_offset < TW_SLOTS_PER_RING);
+#if TW_TIMER_WHEELS > 2
+ glacier_ring_offset +=
+ (tw->current_index[TW_TIMER_RING_GLACIER] & TW_RING_MASK) + carry;
+ glacier_ring_offset %= TW_SLOTS_PER_RING;
+#endif
- /* Timer expires more than 51.2 seconds from now? */
- if (slow_ring_offset)
+#if TW_TIMER_WHEELS > 2
+ if (glacier_ring_offset !=
+ (tw->current_index[TW_TIMER_RING_GLACIER] & TW_RING_MASK))
{
- slow_ring_offset += tw->current_index[TW_TIMER_RING_SLOW];
- slow_ring_offset %= TW_SLOTS_PER_RING;
+ /* We'll need slow and fast ring offsets later */
+ t->slow_ring_offset = slow_ring_offset;
+ t->fast_ring_offset = fast_ring_offset;
+
+ ts = &tw->w[TW_TIMER_RING_GLACIER][glacier_ring_offset];
+
+ timer_addhead (tw->timers, ts->head_index, t - tw->timers);
+#if TW_START_STOP_TRACE_SIZE > 0
+ TW (tw_timer_trace) (tw, timer_id, user_id, t - tw->timers);
+#endif
+ return;
+ }
+#endif
- /* We'll want the fast ring offset later... */
+#if TW_TIMER_WHEELS > 1
+ /* Timer expires more than 51.2 seconds from now? */
+ if (slow_ring_offset !=
+ (tw->current_index[TW_TIMER_RING_SLOW] & TW_RING_MASK))
+ {
+ /* We'll need the fast ring offset later... */
t->fast_ring_offset = fast_ring_offset;
- ASSERT (t->fast_ring_offset < TW_SLOTS_PER_RING);
ts = &tw->w[TW_TIMER_RING_SLOW][slow_ring_offset];
timer_addhead (tw->timers, ts->head_index, t - tw->timers);
-
- return t - tw->timers;
+#if TW_START_STOP_TRACE_SIZE > 0
+ TW (tw_timer_trace) (tw, timer_id, user_id, t - tw->timers);
+#endif
+ return;
}
#else
fast_ring_offset %= TW_SLOTS_PER_RING;
- ASSERT (interval < TW_SLOTS_PER_RING);
#endif
/* Timer expires less than one fast-ring revolution from now */
ts = &tw->w[TW_TIMER_RING_FAST][fast_ring_offset];
timer_addhead (tw->timers, ts->head_index, t - tw->timers);
+
+#if TW_FAST_WHEEL_BITMAP
+ tw->fast_slot_bitmap = clib_bitmap_set (tw->fast_slot_bitmap,
+ fast_ring_offset, 1);
+#endif
+#if TW_START_STOP_TRACE_SIZE > 0
+ TW (tw_timer_trace) (tw, timer_id, user_id, t - tw->timers);
+#endif
+}
+
+/**
+ * @brief Start a Tw Timer
+ * @param tw_timer_wheel_t * tw timer wheel object pointer
+ * @param u32 user_id user defined timer id, presumably for a tw session
+ * @param u32 timer_id app-specific timer ID. 4 bits.
+ * @param u64 interval timer interval in ticks
+ * @returns handle needed to cancel the timer
+ */
+u32
+TW (tw_timer_start) (TWT (tw_timer_wheel) * tw, u32 user_id, u32 timer_id,
+ u64 interval)
+{
+ TWT (tw_timer) * t;
+
+ ASSERT (interval);
+
+ pool_get (tw->timers, t);
+ clib_memset (t, 0xff, sizeof (*t));
+
+ t->user_handle = TW (make_internal_timer_handle) (user_id, timer_id);
+
+ timer_add (tw, t, interval);
return t - tw->timers;
}
+#if TW_TIMER_SCAN_FOR_HANDLE > 0
+int TW (scan_for_handle) (TWT (tw_timer_wheel) * tw, u32 handle)
+{
+ int i, j;
+ tw_timer_wheel_slot_t *ts;
+ TWT (tw_timer) * t, *head;
+ u32 next_index;
+ int rv = 0;
+
+ for (i = 0; i < TW_TIMER_WHEELS; i++)
+ {
+ for (j = 0; j < TW_SLOTS_PER_RING; j++)
+ {
+ ts = &tw->w[i][j];
+ head = pool_elt_at_index (tw->timers, ts->head_index);
+ next_index = head->next;
+
+ while (next_index != ts->head_index)
+ {
+ t = pool_elt_at_index (tw->timers, next_index);
+ if (next_index == handle)
+ {
+ clib_warning ("handle %d found in ring %d slot %d",
+ handle, i, j);
+ clib_warning ("user handle 0x%x", t->user_handle);
+ rv = 1;
+ }
+ next_index = t->next;
+ }
+ }
+ }
+ return rv;
+}
+#endif /* TW_TIMER_SCAN_FOR_HANDLE */
+
/**
* @brief Stop a tw timer
* @param tw_timer_wheel_t * tw timer wheel object pointer
{
TWT (tw_timer) * t;
+#if TW_TIMER_ALLOW_DUPLICATE_STOP
+ /*
+ * A vlib process may have its timer expire, and receive
+ * an event before the expiration is processed.
+ * That results in a duplicate tw_timer_stop.
+ */
+ if (pool_is_free_index (tw->timers, handle))
+ return;
+#endif
+#if TW_START_STOP_TRACE_SIZE > 0
+ TW (tw_timer_trace) (tw, ~0, ~0, handle);
+#endif
+
t = pool_elt_at_index (tw->timers, handle);
/* in case of idiotic handle (e.g. passing a listhead index) */
ASSERT (t->user_handle != ~0);
- timer_remove (tw->timers, handle);
+ timer_remove (tw->timers, t);
pool_put_index (tw->timers, handle);
}
+int TW (tw_timer_handle_is_free) (TWT (tw_timer_wheel) * tw, u32 handle)
+{
+ return pool_is_free_index (tw->timers, handle);
+}
+
+/**
+ * @brief Update a tw timer
+ * @param tw_timer_wheel_t * tw timer wheel object pointer
+ * @param u32 handle timer returned by tw_timer_start
+ * @param u32 interval timer interval in ticks
+ */
+void TW (tw_timer_update) (TWT (tw_timer_wheel) * tw, u32 handle,
+ u64 interval)
+{
+ TWT (tw_timer) * t;
+ t = pool_elt_at_index (tw->timers, handle);
+ timer_remove (tw->timers, t);
+ timer_add (tw, t, interval);
+}
+
/**
* @brief Initialize a tw timer wheel template instance
* @param tw_timer_wheel_t * tw timer wheel object pointer
* @param void * expired_timer_callback. Passed a u32 * vector of
- * expired timer handles.
+ * expired timer handles. The callback is optional.
* @param f64 timer_interval_in_seconds
*/
void
TW (tw_timer_wheel_init) (TWT (tw_timer_wheel) * tw,
void *expired_timer_callback,
- f64 timer_interval_in_seconds)
+ f64 timer_interval_in_seconds, u32 max_expirations)
{
int ring, slot;
tw_timer_wheel_slot_t *ts;
TWT (tw_timer) * t;
- memset (tw, 0, sizeof (*tw));
+ clib_memset (tw, 0, sizeof (*tw));
tw->expired_timer_callback = expired_timer_callback;
+ tw->max_expirations = max_expirations;
if (timer_interval_in_seconds == 0.0)
{
clib_warning ("timer interval is zero");
tw->timer_interval = timer_interval_in_seconds;
tw->ticks_per_second = 1.0 / timer_interval_in_seconds;
+ vec_validate (tw->expired_timer_handles, 0);
+ _vec_len (tw->expired_timer_handles) = 0;
+
for (ring = 0; ring < TW_TIMER_WHEELS; ring++)
{
for (slot = 0; slot < TW_SLOTS_PER_RING; slot++)
{
ts = &tw->w[ring][slot];
pool_get (tw->timers, t);
- memset (t, 0xff, sizeof (*t));
+ clib_memset (t, 0xff, sizeof (*t));
t->next = t->prev = t - tw->timers;
ts->head_index = t - tw->timers;
}
}
+
+#if TW_OVERFLOW_VECTOR > 0
+ ts = &tw->overflow;
+ pool_get (tw->timers, t);
+ clib_memset (t, 0xff, sizeof (*t));
+ t->next = t->prev = t - tw->timers;
+ ts->head_index = t - tw->timers;
+#endif
}
/**
pool_put (tw->timers, head);
}
}
- memset (tw, 0, sizeof (*tw));
+
+#if TW_OVERFLOW_VECTOR > 0
+ ts = &tw->overflow;
+ head = pool_elt_at_index (tw->timers, ts->head_index);
+ next_index = head->next;
+
+ while (next_index != ts->head_index)
+ {
+ t = pool_elt_at_index (tw->timers, next_index);
+ next_index = t->next;
+ pool_put (tw->timers, t);
+ }
+ pool_put (tw->timers, head);
+#endif
+
+ clib_memset (tw, 0, sizeof (*tw));
}
/**
* as needed. This routine should be called once every timer_interval seconds
* @param tw_timer_wheel_t * tw timer wheel template instance pointer
* @param f64 now the current time, e.g. from vlib_time_now(vm)
+ * @returns u32 * vector of expired user handles
*/
-u32 TW (tw_timer_expire_timers) (TWT (tw_timer_wheel) * tw, f64 now)
+static inline
+ u32 * TW (tw_timer_expire_timers_internal) (TWT (tw_timer_wheel) * tw,
+ f64 now,
+ u32 * callback_vector_arg)
{
u32 nticks, i;
tw_timer_wheel_slot_t *ts;
TWT (tw_timer) * t, *head;
+ u32 *callback_vector;
u32 fast_wheel_index;
u32 next_index;
- u32 nexpirations, total_nexpirations;
-#if TW_TIMER_WHEELS > 1
- u32 slow_wheel_index;
-#endif
+ u32 slow_wheel_index __attribute__ ((unused));
+ u32 glacier_wheel_index __attribute__ ((unused));
- /* Shouldn't happen */
+ /* Called too soon to process new timer expirations? */
if (PREDICT_FALSE (now < tw->next_run_time))
- return 0;
+ return callback_vector_arg;
/* Number of ticks which have occurred */
nticks = tw->ticks_per_second * (now - tw->last_run_time);
if (nticks == 0)
- return 0;
+ return callback_vector_arg;
/* Remember when we ran, compute next runtime */
tw->next_run_time = (now + tw->timer_interval);
- tw->last_run_time = now;
- total_nexpirations = 0;
+ /* First call, or time jumped backwards? */
+ if (PREDICT_FALSE
+ ((tw->last_run_time == 0.0) || (now <= tw->last_run_time)))
+ {
+ tw->last_run_time = now;
+ return callback_vector_arg;
+ }
+
+ /*
+ * Refuse to do anything if we're about to process way too many slots.
+ * Should never come anywhere close to happening, with the possible exception
+ * of cases involving a large forward jump in the timebase.
+ */
+ if (nticks > (1 << (TW_RING_SHIFT + 1)))
+ {
+ if (nticks / tw->ticks_per_second > 100e-3)
+ clib_warning ("Excessive nticks %u at %.6f last run %.6f",
+ nticks, now, tw->last_run_time);
+ tw->last_run_time = now;
+ return callback_vector_arg;
+ }
+
+ if (callback_vector_arg == 0)
+ {
+ _vec_len (tw->expired_timer_handles) = 0;
+ callback_vector = tw->expired_timer_handles;
+ }
+ else
+ callback_vector = callback_vector_arg;
+
for (i = 0; i < nticks; i++)
{
fast_wheel_index = tw->current_index[TW_TIMER_RING_FAST];
+ if (TW_TIMER_WHEELS > 1)
+ slow_wheel_index = tw->current_index[TW_TIMER_RING_SLOW];
+ if (TW_TIMER_WHEELS > 2)
+ glacier_wheel_index = tw->current_index[TW_TIMER_RING_GLACIER];
+
+#if TW_OVERFLOW_VECTOR > 0
+ /* Triple odometer-click? Process the overflow vector... */
+ if (PREDICT_FALSE (fast_wheel_index == TW_SLOTS_PER_RING
+ && slow_wheel_index == TW_SLOTS_PER_RING
+ && glacier_wheel_index == TW_SLOTS_PER_RING))
+ {
+ u64 interval;
+ u32 new_glacier_ring_offset, new_slow_ring_offset;
+ u32 new_fast_ring_offset;
+
+ ts = &tw->overflow;
+ head = pool_elt_at_index (tw->timers, ts->head_index);
+ next_index = head->next;
+
+ /* Make slot empty */
+ head->next = head->prev = ts->head_index;
+
+ /* traverse slot, place timers wherever they go */
+ while (next_index != head - tw->timers)
+ {
+ t = pool_elt_at_index (tw->timers, next_index);
+ next_index = t->next;
+
+ /* Remove from the overflow vector (hammer) */
+ t->next = t->prev = ~0;
+
+ ASSERT (t->expiration_time >= tw->current_tick);
+
+ interval = t->expiration_time - tw->current_tick;
+
+ /* Right back onto the overflow vector? */
+ if (interval >= (1 << (3 * TW_RING_SHIFT)))
+ {
+ ts = &tw->overflow;
+ timer_addhead (tw->timers, ts->head_index, t - tw->timers);
+ continue;
+ }
+ /* Compute ring offsets */
+ new_glacier_ring_offset = interval >> (2 * TW_RING_SHIFT);
+
+ interval -= (new_glacier_ring_offset << (2 * TW_RING_SHIFT));
+
+ /* Note: the wheels are at (0,0,0), no add-with-carry needed */
+ new_slow_ring_offset = interval >> TW_RING_SHIFT;
+ interval -= (new_slow_ring_offset << TW_RING_SHIFT);
+ new_fast_ring_offset = interval & TW_RING_MASK;
+ t->slow_ring_offset = new_slow_ring_offset;
+ t->fast_ring_offset = new_fast_ring_offset;
+
+ /* Timer expires Right Now */
+ if (PREDICT_FALSE (t->slow_ring_offset == 0 &&
+ t->fast_ring_offset == 0 &&
+ new_glacier_ring_offset == 0))
+ {
+ vec_add1 (callback_vector, t->user_handle);
+#if TW_START_STOP_TRACE_SIZE > 0
+ TW (tw_timer_trace) (tw, 0xfe, t->user_handle,
+ t - tw->timers);
+#endif
+ pool_put (tw->timers, t);
+ }
+ /* Timer moves to the glacier ring */
+ else if (new_glacier_ring_offset)
+ {
+ ts = &tw->w[TW_TIMER_RING_GLACIER][new_glacier_ring_offset];
+ timer_addhead (tw->timers, ts->head_index, t - tw->timers);
+ }
+ /* Timer moves to the slow ring */
+ else if (t->slow_ring_offset)
+ {
+ /* Add to slow ring */
+ ts = &tw->w[TW_TIMER_RING_SLOW][t->slow_ring_offset];
+ timer_addhead (tw->timers, ts->head_index, t - tw->timers);
+ }
+ /* Timer timer moves to the fast ring */
+ else
+ {
+ ts = &tw->w[TW_TIMER_RING_FAST][t->fast_ring_offset];
+ timer_addhead (tw->timers, ts->head_index, t - tw->timers);
+#if TW_FAST_WHEEL_BITMAP
+ tw->fast_slot_bitmap =
+ clib_bitmap_set (tw->fast_slot_bitmap,
+ t->fast_ring_offset, 1);
+#endif
+ }
+ }
+ }
+#endif
+#if TW_TIMER_WHEELS > 2
/*
- * If we've been around the fast ring once,
- * process one slot in the slow ring before we handle
- * the fast ring.
+ * Double odometer-click? Process one slot in the glacier ring...
*/
- if (PREDICT_FALSE (fast_wheel_index == TW_SLOTS_PER_RING))
+ if (PREDICT_FALSE (fast_wheel_index == TW_SLOTS_PER_RING
+ && slow_wheel_index == TW_SLOTS_PER_RING))
{
- fast_wheel_index = tw->current_index[TW_TIMER_RING_FAST] = 0;
+ glacier_wheel_index %= TW_SLOTS_PER_RING;
+ ts = &tw->w[TW_TIMER_RING_GLACIER][glacier_wheel_index];
-#if TW_TIMER_WHEELS > 1
- tw->current_index[TW_TIMER_RING_SLOW]++;
- tw->current_index[TW_TIMER_RING_SLOW] %= TW_SLOTS_PER_RING;
- slow_wheel_index = tw->current_index[TW_TIMER_RING_SLOW];
+ head = pool_elt_at_index (tw->timers, ts->head_index);
+ next_index = head->next;
+
+ /* Make slot empty */
+ head->next = head->prev = ts->head_index;
+
+ /* traverse slot, deal timers into slow ring */
+ while (next_index != head - tw->timers)
+ {
+ t = pool_elt_at_index (tw->timers, next_index);
+ next_index = t->next;
+ /* Remove from glacier ring slot (hammer) */
+ t->next = t->prev = ~0;
+
+ /* Timer expires Right Now */
+ if (PREDICT_FALSE (t->slow_ring_offset == 0 &&
+ t->fast_ring_offset == 0))
+ {
+ vec_add1 (callback_vector, t->user_handle);
+#if TW_START_STOP_TRACE_SIZE > 0
+ TW (tw_timer_trace) (tw, 0xfe, t->user_handle,
+ t - tw->timers);
+#endif
+ pool_put (tw->timers, t);
+ }
+ /* Timer expires during slow-wheel tick 0 */
+ else if (PREDICT_FALSE (t->slow_ring_offset == 0))
+ {
+ ts = &tw->w[TW_TIMER_RING_FAST][t->fast_ring_offset];
+ timer_addhead (tw->timers, ts->head_index, t - tw->timers);
+#if TW_FAST_WHEEL_BITMAP
+ tw->fast_slot_bitmap =
+ clib_bitmap_set (tw->fast_slot_bitmap,
+ t->fast_ring_offset, 1);
+#endif
+ }
+ else /* typical case */
+ {
+ /* Add to slow ring */
+ ts = &tw->w[TW_TIMER_RING_SLOW][t->slow_ring_offset];
+ timer_addhead (tw->timers, ts->head_index, t - tw->timers);
+ }
+ }
+ }
+#endif
+
+#if TW_TIMER_WHEELS > 1
+ /*
+ * Single odometer-click? Process a slot in the slow ring,
+ */
+ if (PREDICT_FALSE (fast_wheel_index == TW_SLOTS_PER_RING))
+ {
+ slow_wheel_index %= TW_SLOTS_PER_RING;
ts = &tw->w[TW_TIMER_RING_SLOW][slow_wheel_index];
head = pool_elt_at_index (tw->timers, ts->head_index);
t = pool_elt_at_index (tw->timers, next_index);
next_index = t->next;
- /* Remove from slow ring slot (hammer) */
+ /* Remove from sloe ring slot (hammer) */
t->next = t->prev = ~0;
- ASSERT (t->fast_ring_offset < TW_SLOTS_PER_RING);
- /* Add to fast ring */
- ts = &tw->w[TW_TIMER_RING_FAST][t->fast_ring_offset];
- timer_addhead (tw->timers, ts->head_index, t - tw->timers);
- }
+
+ /* Timer expires Right Now */
+ if (PREDICT_FALSE (t->fast_ring_offset == 0))
+ {
+ vec_add1 (callback_vector, t->user_handle);
+#if TW_START_STOP_TRACE_SIZE > 0
+ TW (tw_timer_trace) (tw, 0xfe, t->user_handle,
+ t - tw->timers);
#endif
+ pool_put (tw->timers, t);
+ }
+ else /* typical case */
+ {
+ /* Add to fast ring */
+ ts = &tw->w[TW_TIMER_RING_FAST][t->fast_ring_offset];
+ timer_addhead (tw->timers, ts->head_index, t - tw->timers);
+#if TW_FAST_WHEEL_BITMAP
+ tw->fast_slot_bitmap =
+ clib_bitmap_set (tw->fast_slot_bitmap,
+ t->fast_ring_offset, 1);
+#endif
+ }
+ }
}
+#endif
/* Handle the fast ring */
- vec_reset_length (tw->expired_timer_handles);
-
+ fast_wheel_index %= TW_SLOTS_PER_RING;
ts = &tw->w[TW_TIMER_RING_FAST][fast_wheel_index];
head = pool_elt_at_index (tw->timers, ts->head_index);
{
t = pool_elt_at_index (tw->timers, next_index);
next_index = t->next;
- vec_add1 (tw->expired_timer_handles, t->user_handle);
+ vec_add1 (callback_vector, t->user_handle);
+#if TW_START_STOP_TRACE_SIZE > 0
+ TW (tw_timer_trace) (tw, 0xfe, t->user_handle, t - tw->timers);
+#endif
pool_put (tw->timers, t);
}
/* If any timers expired, tell the user */
- nexpirations = vec_len (tw->expired_timer_handles);
- if (nexpirations)
+ if (callback_vector_arg == 0 && vec_len (callback_vector))
{
- tw->expired_timer_callback (tw->expired_timer_handles);
- total_nexpirations += nexpirations;
+ /* The callback is optional. We return the u32 * handle vector */
+ if (tw->expired_timer_callback)
+ {
+ tw->expired_timer_callback (callback_vector);
+ vec_reset_length (callback_vector);
+ }
+ tw->expired_timer_handles = callback_vector;
}
- tw->current_index[TW_TIMER_RING_FAST]++;
+
+#if TW_FAST_WHEEL_BITMAP
+ tw->fast_slot_bitmap = clib_bitmap_set (tw->fast_slot_bitmap,
+ fast_wheel_index, 0);
+#endif
+
tw->current_tick++;
+ fast_wheel_index++;
+ tw->current_index[TW_TIMER_RING_FAST] = fast_wheel_index;
+
+#if TW_TIMER_WHEELS > 1
+ if (PREDICT_FALSE (fast_wheel_index == TW_SLOTS_PER_RING))
+ slow_wheel_index++;
+ tw->current_index[TW_TIMER_RING_SLOW] = slow_wheel_index;
+#endif
+
+#if TW_TIMER_WHEELS > 2
+ if (PREDICT_FALSE (slow_wheel_index == TW_SLOTS_PER_RING))
+ glacier_wheel_index++;
+ tw->current_index[TW_TIMER_RING_GLACIER] = glacier_wheel_index;
+#endif
+
+ if (vec_len (callback_vector) >= tw->max_expirations)
+ break;
}
- return total_nexpirations;
+ if (callback_vector_arg == 0)
+ tw->expired_timer_handles = callback_vector;
+
+ tw->last_run_time += i * tw->timer_interval;
+ return callback_vector;
+}
+
+u32 *TW (tw_timer_expire_timers) (TWT (tw_timer_wheel) * tw, f64 now)
+{
+ return TW (tw_timer_expire_timers_internal) (tw, now, 0 /* no vector */ );
}
+u32 *TW (tw_timer_expire_timers_vec) (TWT (tw_timer_wheel) * tw, f64 now,
+ u32 * vec)
+{
+ return TW (tw_timer_expire_timers_internal) (tw, now, vec);
+}
+
+#if TW_FAST_WHEEL_BITMAP
+/** Returns an approximation to the first timer expiration in
+ * timer-ticks from "now". To avoid wasting an unjustifiable
+ * amount of time on the problem, we maintain an approximate fast-wheel slot
+ * occupancy bitmap. We don't worry about clearing fast wheel bits
+ * when timers are removed from fast wheel slots.
+ */
+
+u32 TW (tw_timer_first_expires_in_ticks) (TWT (tw_timer_wheel) * tw)
+{
+ u32 first_expiring_index, fast_ring_index;
+ i32 delta;
+
+#if TW_TIMER_WHEELS > 1
+ fast_ring_index = tw->current_index[TW_TIMER_RING_FAST];
+ if (fast_ring_index == TW_SLOTS_PER_RING)
+ return 1;
+
+ first_expiring_index = clib_bitmap_next_set (tw->fast_slot_bitmap,
+ fast_ring_index);
+ if (first_expiring_index == ~0)
+ first_expiring_index = TW_SLOTS_PER_RING;
+
+#else
+
+ if (clib_bitmap_is_zero (tw->fast_slot_bitmap))
+ return TW_SLOTS_PER_RING;
+
+ fast_ring_index = tw->current_index[TW_TIMER_RING_FAST];
+ if (fast_ring_index == TW_SLOTS_PER_RING)
+ fast_ring_index = 0;
+
+ first_expiring_index = clib_bitmap_next_set (tw->fast_slot_bitmap,
+ fast_ring_index);
+ if (first_expiring_index == ~0 && fast_ring_index != 0)
+ first_expiring_index = clib_bitmap_first_set (tw->fast_slot_bitmap);
+#endif
+
+ ASSERT (first_expiring_index != ~0);
+
+ delta = (i32) first_expiring_index - (i32) fast_ring_index;
+ if (delta < 0)
+ delta += TW_SLOTS_PER_RING;
+
+ ASSERT (delta >= 0);
+
+ return (u32) delta;
+}
+
+#endif
+
/*
* fd.io coding-style-patch-verification: ON
*
Code Review / vpp.git / blobdiff