static int prb_queue_frozen(struct tpacket_kbdq_core *);
static void prb_open_block(struct tpacket_kbdq_core *,
struct tpacket_block_desc *);
-static void prb_retire_rx_blk_timer_expired(struct timer_list *);
-static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *);
+static enum hrtimer_restart prb_retire_rx_blk_timer_expired(struct hrtimer *);
static void prb_fill_rxhash(struct tpacket_kbdq_core *, struct tpacket3_hdr *);
static void prb_clear_rxhash(struct tpacket_kbdq_core *,
struct tpacket3_hdr *);
return proto;
}
-static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
-{
- timer_delete_sync(&pkc->retire_blk_timer);
-}
-
static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
struct sk_buff_head *rb_queue)
{
struct tpacket_kbdq_core *pkc;
pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
-
- spin_lock_bh(&rb_queue->lock);
- pkc->delete_blk_timer = 1;
- spin_unlock_bh(&rb_queue->lock);
-
- prb_del_retire_blk_timer(pkc);
-}
-
-static void prb_setup_retire_blk_timer(struct packet_sock *po)
-{
- struct tpacket_kbdq_core *pkc;
-
- pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
- timer_setup(&pkc->retire_blk_timer, prb_retire_rx_blk_timer_expired,
- 0);
- pkc->retire_blk_timer.expires = jiffies;
+ hrtimer_cancel(&pkc->retire_blk_timer);
}
static int prb_calc_retire_blk_tmo(struct packet_sock *po,
p1->version = po->tp_version;
po->stats.stats3.tp_freeze_q_cnt = 0;
if (req_u->req3.tp_retire_blk_tov)
- p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
+ p1->interval_ktime = ms_to_ktime(req_u->req3.tp_retire_blk_tov);
else
- p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
- req_u->req3.tp_block_size);
- p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
+ p1->interval_ktime = ms_to_ktime(prb_calc_retire_blk_tmo(po,
+ req_u->req3.tp_block_size));
p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
rwlock_init(&p1->blk_fill_in_prog_lock);
p1->max_frame_len = p1->kblk_size - BLK_PLUS_PRIV(p1->blk_sizeof_priv);
prb_init_ft_ops(p1, req_u);
- prb_setup_retire_blk_timer(po);
+ hrtimer_setup(&p1->retire_blk_timer, prb_retire_rx_blk_timer_expired,
+ CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
+ hrtimer_start(&p1->retire_blk_timer, p1->interval_ktime,
+ HRTIMER_MODE_REL_SOFT);
prb_open_block(p1, pbd);
}
-/* Do NOT update the last_blk_num first.
- * Assumes sk_buff_head lock is held.
- */
-static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
-{
- mod_timer(&pkc->retire_blk_timer,
- jiffies + pkc->tov_in_jiffies);
-}
-
/*
- * Timer logic:
- * 1) We refresh the timer only when we open a block.
- * By doing this we don't waste cycles refreshing the timer
- * on packet-by-packet basis.
- *
* With a 1MB block-size, on a 1Gbps line, it will take
* i) ~8 ms to fill a block + ii) memcpy etc.
* In this cut we are not accounting for the memcpy time.
*
- * So, if the user sets the 'tmo' to 10ms then the timer
- * will never fire while the block is still getting filled
- * (which is what we want). However, the user could choose
- * to close a block early and that's fine.
- *
- * But when the timer does fire, we check whether or not to refresh it.
* Since the tmo granularity is in msecs, it is not too expensive
* to refresh the timer, lets say every '8' msecs.
* Either the user can set the 'tmo' or we can derive it based on
* a) line-speed and b) block-size.
* prb_calc_retire_blk_tmo() calculates the tmo.
- *
*/
-static void prb_retire_rx_blk_timer_expired(struct timer_list *t)
+static enum hrtimer_restart prb_retire_rx_blk_timer_expired(struct hrtimer *t)
{
struct packet_sock *po =
timer_container_of(po, t, rx_ring.prb_bdqc.retire_blk_timer);
frozen = prb_queue_frozen(pkc);
pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
- if (unlikely(pkc->delete_blk_timer))
- goto out;
-
/* We only need to plug the race when the block is partially filled.
* tpacket_rcv:
* lock(); increment BLOCK_NUM_PKTS; unlock()
}
if (!frozen) {
- if (!BLOCK_NUM_PKTS(pbd)) {
- /* An empty block. Just refresh the timer. */
- goto refresh_timer;
+ if (BLOCK_NUM_PKTS(pbd)) {
+ /* Not an empty block. Need retire the block. */
+ prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
+ prb_dispatch_next_block(pkc, po);
}
- prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
- if (!prb_dispatch_next_block(pkc, po))
- goto refresh_timer;
- else
- goto out;
} else {
/* Case 1. Queue was frozen because user-space was
* lagging behind.
*/
- if (prb_curr_blk_in_use(pbd)) {
- /*
- * Ok, user-space is still behind.
- * So just refresh the timer.
- */
- goto refresh_timer;
- } else {
+ if (!prb_curr_blk_in_use(pbd)) {
/* Case 2. queue was frozen,user-space caught up,
* now the link went idle && the timer fired.
* We don't have a block to close.So we open this
* Thawing/timer-refresh is a side effect.
*/
prb_open_block(pkc, pbd);
- goto out;
}
}
-refresh_timer:
- _prb_refresh_rx_retire_blk_timer(pkc);
-
-out:
+ hrtimer_forward_now(&pkc->retire_blk_timer, pkc->interval_ktime);
spin_unlock(&po->sk.sk_receive_queue.lock);
+ return HRTIMER_RESTART;
}
static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
}
/*
- * Side effect of opening a block:
+ * prb_open_block is called by tpacket_rcv or timer callback.
*
- * 1) prb_queue is thawed.
- * 2) retire_blk_timer is refreshed.
+ * Reasons why NOT update hrtimer in prb_open_block:
+ * 1) It will increase complexity to distinguish the two caller scenario.
+ * 2) hrtimer_cancel and hrtimer_start need to be called if you want to update
+ * TMO of an already enqueued hrtimer, leading to complex shutdown logic.
*
+ * One side effect of NOT update hrtimer when called by tpacket_rcv is that
+ * a newly opened block triggered by tpacket_rcv may be retired earlier than
+ * expected. On the other hand, if timeout is updated in prb_open_block, the
+ * frequent reception of network packets that leads to prb_open_block being
+ * called may cause hrtimer to be removed and enqueued repeatedly.
*/
static void prb_open_block(struct tpacket_kbdq_core *pkc1,
struct tpacket_block_desc *pbd1)
pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
prb_thaw_queue(pkc1);
- _prb_refresh_rx_retire_blk_timer(pkc1);
smp_wmb();
}
projects / users / hch / misc.git / commitdiff