From: Marek Lindner Date: Fri, 7 May 2010 19:47:08 +0000 (+0200) Subject: Staging: batman-adv: fix aggregation timing bug X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=bd13b616aa9d082dce760759b7473da5ed399452;p=deliverable%2Flinux.git Staging: batman-adv: fix aggregation timing bug batman-adv aggregates routing packets to reduce the number of packets in the air. Every outgoing packet is compared with other packets in the buffer to determine whether it can be aggregated or not. Packets sent at a lower interval can be held back longer to maximize the aggregation. Due to insufficient checking batman-adv held back all packets for a certain time depending on its own lowest interval rate which slowed down all other nodes. Reported-by: Linus Lüssing Signed-off-by: Marek Lindner Signed-off-by: Andrew Lunn Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/staging/batman-adv/aggregation.c b/drivers/staging/batman-adv/aggregation.c index 7917322a7e2a..d25e5a89dac3 100644 --- a/drivers/staging/batman-adv/aggregation.c +++ b/drivers/staging/batman-adv/aggregation.c @@ -52,6 +52,8 @@ static bool can_aggregate_with(struct batman_packet *new_batman_packet, */ if (time_before(send_time, forw_packet->send_time) && + time_after_eq(send_time + msecs_to_jiffies(MAX_AGGREGATION_MS), + forw_packet->send_time) && (aggregated_bytes <= MAX_AGGREGATION_BYTES)) { /** @@ -195,6 +197,16 @@ void add_bat_packet_to_list(unsigned char *packet_buff, int packet_len, if (forw_packet_aggr == NULL) { /* the following section can run without the lock */ spin_unlock_irqrestore(&forw_bat_list_lock, flags); + + /** + * if we could not aggregate this packet with one of the others + * we hold it back for a while, so that it might be aggregated + * later on + */ + if ((!own_packet) && + (atomic_read(&bat_priv->aggregation_enabled))) + send_time += msecs_to_jiffies(MAX_AGGREGATION_MS); + new_aggregated_packet(packet_buff, packet_len, send_time, direct_link, if_incoming, own_packet); diff --git a/drivers/staging/batman-adv/send.c b/drivers/staging/batman-adv/send.c index ff7b1f10684f..d356ce7644a3 100644 --- a/drivers/staging/batman-adv/send.c +++ b/drivers/staging/batman-adv/send.c @@ -46,15 +46,7 @@ static unsigned long own_send_time(void) /* when do we schedule a forwarded packet to be sent */ static unsigned long forward_send_time(void) { - unsigned long send_time = jiffies; /* Starting now plus... */ - - if (atomic_read(&aggregation_enabled)) - send_time += (((MAX_AGGREGATION_MS - (JITTER/2) + - (random32() % JITTER)) * HZ) / 1000); - else - send_time += (((random32() % (JITTER/2)) * HZ) / 1000); - - return send_time; + return jiffies + (((random32() % (JITTER/2)) * HZ) / 1000); } /* send out an already prepared packet to the given address via the