diff options
Diffstat (limited to 'debian/patches/features/all/ethernet-microsoft/0026-net-mana-Batch-ringing-RX-queue-doorbell-on-receivin.patch')
| -rw-r--r-- | debian/patches/features/all/ethernet-microsoft/0026-net-mana-Batch-ringing-RX-queue-doorbell-on-receivin.patch | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/debian/patches/features/all/ethernet-microsoft/0026-net-mana-Batch-ringing-RX-queue-doorbell-on-receivin.patch b/debian/patches/features/all/ethernet-microsoft/0026-net-mana-Batch-ringing-RX-queue-doorbell-on-receivin.patch new file mode 100644 index 000000000..6f03091cd --- /dev/null +++ b/debian/patches/features/all/ethernet-microsoft/0026-net-mana-Batch-ringing-RX-queue-doorbell-on-receivin.patch @@ -0,0 +1,62 @@ +From ad96bbb0b221f0cc22fba13a28234636bf7fb9f5 Mon Sep 17 00:00:00 2001 +From: Long Li <longli@microsoft.com> +Date: Mon, 17 Jul 2023 12:35:38 -0700 +Subject: [PATCH 26/30] net: mana: Batch ringing RX queue doorbell on receiving + packets + +It's inefficient to ring the doorbell page every time a WQE is posted to +the received queue. Excessive MMIO writes result in CPU spending more +time waiting on LOCK instructions (atomic operations), resulting in +poor scaling performance. + +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(). + +With this change, tests showed an improvement from 120G/s to 160G/s on a +200G physical link, with 16 or 32 hardware queues. + +Tests showed no regression in network latency benchmarks on single +connection. + +Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com> +Reviewed-by: Dexuan Cui <decui@microsoft.com> +Signed-off-by: Long Li <longli@microsoft.com> +Link: https://lore.kernel.org/r/1689622539-5334-2-git-send-email-longli@linuxonhyperv.com +Signed-off-by: Jakub Kicinski <kuba@kernel.org> +(cherry picked from commit da4e8648079eb6f26f3a88d8c34270a057e2bfe6) +Signed-off-by: Bastian Blank <waldi@debian.org> +--- + 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 7d82b8949a1e..75c1f81ce64f 100644 +--- a/drivers/net/ethernet/microsoft/mana/mana_en.c ++++ b/drivers/net/ethernet/microsoft/mana/mana_en.c +@@ -1387,8 +1387,8 @@ 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); + if (WARN_ON_ONCE(err)) + return; + +@@ -1660,6 +1660,12 @@ static void mana_poll_rx_cq(struct mana_cq *cq) + mana_process_rx_cqe(rxq, cq, &comp[i]); + } + ++ if (comp_read > 0) { ++ struct gdma_context *gc = rxq->gdma_rq->gdma_dev->gdma_context; ++ ++ mana_gd_wq_ring_doorbell(gc, rxq->gdma_rq); ++ } ++ + if (rxq->xdp_flush) + xdp_do_flush(); + } +-- +2.40.1 + |