From 4bccfc036abbdf510de808925c646c8c49e0309e Mon Sep 17 00:00:00 2001 From: Rahul Lakkireddy Date: Fri, 15 May 2020 22:41:04 +0530 Subject: cxgb4: tune burst buffer size for TC-MQPRIO offload For each traffic class, firmware handles up to 4 * MTU amount of data per burst cycle. Under heavy load, this small buffer size is a bottleneck when buffering large TSO packets in <= 1500 MTU case. Increase the burst buffer size to 8 * MTU when supported. Also, keep the driver's traffic class configuration API similar to the firmware API counterpart. Signed-off-by: Rahul Lakkireddy Signed-off-by: David S. Miller --- drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_mqprio.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_mqprio.c') diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_mqprio.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_mqprio.c index e6af4906d674..56079c9937db 100644 --- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_mqprio.c +++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_mqprio.c @@ -342,6 +342,13 @@ static int cxgb4_mqprio_alloc_tc(struct net_device *dev, p.u.params.minrate = div_u64(mqprio->min_rate[i] * 8, 1000); p.u.params.maxrate = div_u64(mqprio->max_rate[i] * 8, 1000); + /* Request larger burst buffer for smaller MTU, so + * that hardware can work on more data per burst + * cycle. + */ + if (dev->mtu <= ETH_DATA_LEN) + p.u.params.burstsize = 8 * dev->mtu; + e = cxgb4_sched_class_alloc(dev, &p); if (!e) { ret = -ENOMEM; -- cgit v1.2.3-59-g8ed1b