3.12-stable review patch. If anyone has any objections, please let me know.
------------------ From: Laurence Evans <[email protected]> [ Upstream commit f32116003c39f3a6815215a7512e1ea8d1e4bbc7 ] Limit syslog flood if a PTP packet storm occurs. Fixes: 7c236c43b838 ('sfc: Add support for IEEE-1588 PTP') Signed-off-by: Ben Hutchings <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/net/ethernet/sfc/ptp.c | 23 +++++++++++++++++++++-- 1 file changed, 21 insertions(+), 2 deletions(-) --- a/drivers/net/ethernet/sfc/ptp.c +++ b/drivers/net/ethernet/sfc/ptp.c @@ -220,6 +220,7 @@ struct efx_ptp_timeset { * @evt_list: List of MC receive events awaiting packets * @evt_free_list: List of free events * @evt_lock: Lock for manipulating evt_list and evt_free_list + * @evt_overflow: Boolean indicating that event list has overflowed * @rx_evts: Instantiated events (on evt_list and evt_free_list) * @workwq: Work queue for processing pending PTP operations * @work: Work task @@ -270,6 +271,7 @@ struct efx_ptp_data { struct list_head evt_list; struct list_head evt_free_list; spinlock_t evt_lock; + bool evt_overflow; struct efx_ptp_event_rx rx_evts[MAX_RECEIVE_EVENTS]; struct workqueue_struct *workwq; struct work_struct work; @@ -635,6 +637,11 @@ static void efx_ptp_drop_time_expired_ev } } } + /* If the event overflow flag is set and the event list is now empty + * clear the flag to re-enable the overflow warning message. + */ + if (ptp->evt_overflow && list_empty(&ptp->evt_list)) + ptp->evt_overflow = false; spin_unlock_bh(&ptp->evt_lock); } @@ -676,6 +683,11 @@ static enum ptp_packet_state efx_ptp_mat break; } } + /* If the event overflow flag is set and the event list is now empty + * clear the flag to re-enable the overflow warning message. + */ + if (ptp->evt_overflow && list_empty(&ptp->evt_list)) + ptp->evt_overflow = false; spin_unlock_bh(&ptp->evt_lock); return rc; @@ -809,6 +821,7 @@ static int efx_ptp_stop(struct efx_nic * list_for_each_safe(cursor, next, &efx->ptp_data->evt_list) { list_move(cursor, &efx->ptp_data->evt_free_list); } + ptp->evt_overflow = false; spin_unlock_bh(&efx->ptp_data->evt_lock); return rc; @@ -901,6 +914,7 @@ static int efx_ptp_probe_channel(struct spin_lock_init(&ptp->evt_lock); for (pos = 0; pos < MAX_RECEIVE_EVENTS; pos++) list_add(&ptp->rx_evts[pos].link, &ptp->evt_free_list); + ptp->evt_overflow = false; ptp->phc_clock_info.owner = THIS_MODULE; snprintf(ptp->phc_clock_info.name, @@ -1299,8 +1313,13 @@ static void ptp_event_rx(struct efx_nic list_add_tail(&evt->link, &ptp->evt_list); queue_work(ptp->workwq, &ptp->work); - } else { - netif_err(efx, rx_err, efx->net_dev, "No free PTP event"); + } else if (!ptp->evt_overflow) { + /* Log a warning message and set the event overflow flag. + * The message won't be logged again until the event queue + * becomes empty. + */ + netif_err(efx, rx_err, efx->net_dev, "PTP event queue overflow\n"); + ptp->evt_overflow = true; } spin_unlock_bh(&ptp->evt_lock); } -- 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/
