From 2e71a6f8084e7ac87166dd77d99c44190fb844fc Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sat, 6 Oct 2012 08:08:49 +0000 Subject: net: gro: selective flush of packets Current GRO can hold packets in gro_list for almost unlimited time, in case napi->poll() handler consumes its budget over and over. In this case, napi_complete()/napi_gro_flush() are not called. Another problem is that gro_list is flushed in non friendly way : We scan the list and complete packets in the reverse order. (youngest packets first, oldest packets last) This defeats priorities that sender could have cooked. Since GRO currently only store TCP packets, we dont really notice the bug because of retransmits, but this behavior can add unexpected latencies, particularly on mice flows clamped by elephant flows. This patch makes sure no packet can stay more than 1 ms in queue, and only in stress situations. It also complete packets in the right order to minimize latencies. Signed-off-by: Eric Dumazet Cc: Herbert Xu Cc: Jesse Gross Cc: Tom Herbert Cc: Yuchung Cheng Signed-off-by: David S. Miller --- drivers/net/ethernet/marvell/skge.c | 2 +- drivers/net/ethernet/realtek/8139cp.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers') diff --git a/drivers/net/ethernet/marvell/skge.c b/drivers/net/ethernet/marvell/skge.c index 3f7dab46626b..9b9c2ac5c4c2 100644 --- a/drivers/net/ethernet/marvell/skge.c +++ b/drivers/net/ethernet/marvell/skge.c @@ -3189,7 +3189,7 @@ static int skge_poll(struct napi_struct *napi, int to_do) if (work_done < to_do) { unsigned long flags; - napi_gro_flush(napi); + napi_gro_flush(napi, false); spin_lock_irqsave(&hw->hw_lock, flags); __napi_complete(napi); hw->intr_mask |= napimask[skge->port]; diff --git a/drivers/net/ethernet/realtek/8139cp.c b/drivers/net/ethernet/realtek/8139cp.c index 995d0cfc4c06..1c818254b7be 100644 --- a/drivers/net/ethernet/realtek/8139cp.c +++ b/drivers/net/ethernet/realtek/8139cp.c @@ -563,7 +563,7 @@ rx_next: if (cpr16(IntrStatus) & cp_rx_intr_mask) goto rx_status_loop; - napi_gro_flush(napi); + napi_gro_flush(napi, false); spin_lock_irqsave(&cp->lock, flags); __napi_complete(napi); cpw16_f(IntrMask, cp_intr_mask); -- cgit v1.2.3