-----Original Message----- From: longli@linuxonhyperv.com longli@linuxonhyperv.com Sent: Thursday, June 15, 2023 7:28 PM To: KY Srinivasan kys@microsoft.com; Haiyang Zhang haiyangz@microsoft.com; Wei Liu wei.liu@kernel.org; Dexuan Cui decui@microsoft.com; David S. Miller davem@davemloft.net; Eric Dumazet edumazet@google.com; Jakub Kicinski kuba@kernel.org; Paolo Abeni pabeni@redhat.com; Leon Romanovsky leon@kernel.org; Shradha Gupta shradhagupta@linux.microsoft.com; Ajay Sharma sharmaajay@microsoft.com; Shachar Raindel shacharr@microsoft.com; Stephen Hemminger stephen@networkplumber.org; linux- hyperv@vger.kernel.org; netdev@vger.kernel.org; linux- kernel@vger.kernel.org Cc: linux-rdma@vger.kernel.org; Long Li longli@microsoft.com; stable@vger.kernel.org Subject: [PATCH] net: mana: Batch ringing RX queue doorbell on receiving packets
From: Long Li longli@microsoft.com
It's inefficient to ring the doorbell page every time a WQE is posted to the received queue.
Move the code for ringing doorbell page to where after we have posted all WQEs to the receive queue during a callback from napi_poll().
Tests showed no regression in network latency benchmarks.
Cc: stable@vger.kernel.org Fixes: ca9c54d2d6a5 ("net: mana: Add a driver for Microsoft Azure Network Adapter (MANA)") Signed-off-by: Long Li longli@microsoft.com
drivers/net/ethernet/microsoft/mana/mana_en.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c index cd4d5ceb9f2d..ef1f0ce8e44d 100644 --- a/drivers/net/ethernet/microsoft/mana/mana_en.c +++ b/drivers/net/ethernet/microsoft/mana/mana_en.c @@ -1383,8 +1383,8 @@ static void mana_post_pkt_rxq(struct mana_rxq *rxq)
recv_buf_oob = &rxq->rx_oobs[curr_index];
- err = mana_gd_post_and_ring(rxq->gdma_rq, &recv_buf_oob-
wqe_req,
&recv_buf_oob->wqe_inf);
- err = mana_gd_post_work_request(rxq->gdma_rq, &recv_buf_oob-
wqe_req,
&recv_buf_oob->wqe_inf);@@ -1654,6 +1654,12 @@ static void mana_poll_rx_cq(struct mana_cq *cq) mana_process_rx_cqe(rxq, cq, &comp[i]); }
- if (comp_read) {
struct gdma_context *gc = rxq->gdma_rq->gdma_dev-gdma_context;
mana_gd_wq_ring_doorbell(gc, rxq->gdma_rq);- }
Thank you!
Reviewed-by: Haiyang Zhang haiyangz@microsoft.com