From 18e1d2beb6c2307d3cab7ecb44fd3d4382adcf6a Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Thu, 29 Oct 2009 07:21:24 +0000 Subject: [PATCH] sfc: Feed GRO result into RX allocation policy and interrupt moderation When GRO is successfully merging received packets, we should allocate raw page buffers rather than skbs that will be discarded by GRO. Otherwise, we should allocate skbs. GRO also benefits from higher interrupt moderation, so increase the score for mergeable RX packets. Signed-off-by: Ben Hutchings Signed-off-by: David S. Miller --- drivers/net/sfc/rx.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/net/sfc/rx.c b/drivers/net/sfc/rx.c index 4b65c62..9277e9a 100644 --- a/drivers/net/sfc/rx.c +++ b/drivers/net/sfc/rx.c @@ -445,6 +445,7 @@ static void efx_rx_packet_lro(struct efx_channel *channel, bool checksummed) { struct napi_struct *napi = &channel->napi_str; + gro_result_t gro_result; /* Pass the skb/page into the LRO engine */ if (rx_buf->page) { @@ -452,6 +453,7 @@ static void efx_rx_packet_lro(struct efx_channel *channel, if (!skb) { put_page(rx_buf->page); + gro_result = GRO_DROP; goto out; } @@ -467,7 +469,7 @@ static void efx_rx_packet_lro(struct efx_channel *channel, skb->ip_summed = checksummed ? CHECKSUM_UNNECESSARY : CHECKSUM_NONE; - napi_gro_frags(napi); + gro_result = napi_gro_frags(napi); out: EFX_BUG_ON_PARANOID(rx_buf->skb); @@ -476,9 +478,16 @@ out: EFX_BUG_ON_PARANOID(!rx_buf->skb); EFX_BUG_ON_PARANOID(!checksummed); - napi_gro_receive(napi, rx_buf->skb); + gro_result = napi_gro_receive(napi, rx_buf->skb); rx_buf->skb = NULL; } + + if (gro_result == GRO_NORMAL) { + channel->rx_alloc_level += RX_ALLOC_FACTOR_SKB; + } else if (gro_result != GRO_DROP) { + channel->rx_alloc_level += RX_ALLOC_FACTOR_LRO; + channel->irq_mod_score += 2; + } } void efx_rx_packet(struct efx_rx_queue *rx_queue, unsigned int index, -- 2.7.4