On 2015/4/15 3:42, Thomas Gleixner wrote: > The code sets the expiry value of the timer to a relative value and > starts it with hrtimer_start_expires. That's fine, but that only works > once. The timer is started in relative mode, so the expiry value gets > overwritten with the absolut expiry time (now + expiry). > > So once the timer expired, a new call to hrtimer_start_expires results > in an immidiately expired timer, because the expiry value is > already in the past. > > Use the proper mechanisms to (re)start the timer in the intended way. >
Acked-by: Ding Tianhong <[email protected]> > Signed-off-by: Thomas Gleixner <[email protected]> > Cc: "David S. Miller" <[email protected]> > Cc: dingtianhong <[email protected]> > Cc: Arnd Bergmann <[email protected]> > Cc: Zhangfei Gao <[email protected]> > Cc: Dan Carpenter <[email protected]> > Cc: [email protected] > --- > drivers/net/ethernet/hisilicon/hip04_eth.c | 18 +++++++++++------- > 1 file changed, 11 insertions(+), 7 deletions(-) > > Index: linux/drivers/net/ethernet/hisilicon/hip04_eth.c > =================================================================== > --- linux.orig/drivers/net/ethernet/hisilicon/hip04_eth.c > +++ linux/drivers/net/ethernet/hisilicon/hip04_eth.c > @@ -413,6 +413,15 @@ out: > return count; > } > > +static void hip04_start_tx_timer(struct hip04_priv *priv) > +{ > + unsigned long ns = priv->tx_coalesce_usecs * NSEC_PER_USEC / 2; > + > + /* allow timer to fire after half the time at the earliest */ > + hrtimer_start_range_ns(&priv->tx_coalesce_timer, ns_to_ktime(ns), > + ns, HRTIMER_MODE_REL); > +} > + > static int hip04_mac_start_xmit(struct sk_buff *skb, struct net_device *ndev) > { > struct hip04_priv *priv = netdev_priv(ndev); > @@ -466,8 +475,7 @@ static int hip04_mac_start_xmit(struct s > } > } else if (!hrtimer_is_queued(&priv->tx_coalesce_timer)) { > /* cleanup not pending yet, start a new timer */ > - hrtimer_start_expires(&priv->tx_coalesce_timer, > - HRTIMER_MODE_REL); > + hip04_start_tx_timer(priv); > } > > return NETDEV_TX_OK; > @@ -549,7 +557,7 @@ done: > /* clean up tx descriptors and start a new timer if necessary */ > tx_remaining = hip04_tx_reclaim(ndev, false); > if (rx < budget && tx_remaining) > - hrtimer_start_expires(&priv->tx_coalesce_timer, > HRTIMER_MODE_REL); > + hip04_start_tx_timer(priv); > > return rx; > } > @@ -809,7 +817,6 @@ static int hip04_mac_probe(struct platfo > struct hip04_priv *priv; > struct resource *res; > unsigned int irq; > - ktime_t txtime; > int ret; > > ndev = alloc_etherdev(sizeof(struct hip04_priv)); > @@ -846,9 +853,6 @@ static int hip04_mac_probe(struct platfo > */ > priv->tx_coalesce_frames = TX_DESC_NUM * 3 / 4; > priv->tx_coalesce_usecs = 200; > - /* allow timer to fire after half the time at the earliest */ > - txtime = ktime_set(0, priv->tx_coalesce_usecs * NSEC_PER_USEC / 2); > - hrtimer_set_expires_range(&priv->tx_coalesce_timer, txtime, txtime); > priv->tx_coalesce_timer.function = tx_done; > > priv->map = syscon_node_to_regmap(arg.np); > > . > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
