From c936835c1ec6f871f32c9b87a7708700320075b3 Mon Sep 17 00:00:00 2001 From: Peter Dunning Date: Wed, 8 Jul 2015 10:05:10 +0100 Subject: [PATCH] sfc: Report TX completions to BQL after all TX events in interrupt The limit for BQL is updated each time we call netdev_tx_completed_queue. Without this patch the BQL limit was updated for every TX event we see. The issue was that this only updated the limit to handle the data we complete in two events as the first event wouldn't show that enough traffic had been processed between them. This was OK when interrupt moderation was off but not when it was on as more data had to be completed in a single interrupt. The patch changes this so that we do report the completion to BQL only when all the TX events in the interrupt have been processed. Signed-off-by: Shradha Shah Signed-off-by: David S. Miller --- drivers/net/ethernet/sfc/efx.c | 14 ++++++++++++++ drivers/net/ethernet/sfc/net_driver.h | 2 ++ drivers/net/ethernet/sfc/tx.c | 3 ++- 3 files changed, 18 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/sfc/efx.c b/drivers/net/ethernet/sfc/efx.c index 804b9ad553d3..03bc03b67f08 100644 --- a/drivers/net/ethernet/sfc/efx.c +++ b/drivers/net/ethernet/sfc/efx.c @@ -245,11 +245,17 @@ static int efx_check_disabled(struct efx_nic *efx) */ static int efx_process_channel(struct efx_channel *channel, int budget) { + struct efx_tx_queue *tx_queue; int spent; if (unlikely(!channel->enabled)) return 0; + efx_for_each_channel_tx_queue(tx_queue, channel) { + tx_queue->pkts_compl = 0; + tx_queue->bytes_compl = 0; + } + spent = efx_nic_process_eventq(channel, budget); if (spent && efx_channel_has_rx_queue(channel)) { struct efx_rx_queue *rx_queue = @@ -259,6 +265,14 @@ static int efx_process_channel(struct efx_channel *channel, int budget) efx_fast_push_rx_descriptors(rx_queue, true); } + /* Update BQL */ + efx_for_each_channel_tx_queue(tx_queue, channel) { + if (tx_queue->bytes_compl) { + netdev_tx_completed_queue(tx_queue->core_txq, + tx_queue->pkts_compl, tx_queue->bytes_compl); + } + } + return spent; } diff --git a/drivers/net/ethernet/sfc/net_driver.h b/drivers/net/ethernet/sfc/net_driver.h index d72f522bf9c3..47d1e3a96522 100644 --- a/drivers/net/ethernet/sfc/net_driver.h +++ b/drivers/net/ethernet/sfc/net_driver.h @@ -241,6 +241,8 @@ struct efx_tx_queue { unsigned int read_count ____cacheline_aligned_in_smp; unsigned int old_write_count; unsigned int merge_events; + unsigned int bytes_compl; + unsigned int pkts_compl; /* Members used only on the xmit path */ unsigned int insert_count ____cacheline_aligned_in_smp; diff --git a/drivers/net/ethernet/sfc/tx.c b/drivers/net/ethernet/sfc/tx.c index aaf2987512b5..1833a0146571 100644 --- a/drivers/net/ethernet/sfc/tx.c +++ b/drivers/net/ethernet/sfc/tx.c @@ -617,7 +617,8 @@ void efx_xmit_done(struct efx_tx_queue *tx_queue, unsigned int index) EFX_BUG_ON_PARANOID(index > tx_queue->ptr_mask); efx_dequeue_buffers(tx_queue, index, &pkts_compl, &bytes_compl); - netdev_tx_completed_queue(tx_queue->core_txq, pkts_compl, bytes_compl); + tx_queue->pkts_compl += pkts_compl; + tx_queue->bytes_compl += bytes_compl; if (pkts_compl > 1) ++tx_queue->merge_events; -- 2.20.1