{"id":809200,"url":"http://patchwork.ozlabs.org/api/patches/809200/?format=json","web_url":"http://patchwork.ozlabs.org/project/netdev/patch/20170903042117.28923-16-saeedm@mellanox.com/","project":{"id":7,"url":"http://patchwork.ozlabs.org/api/projects/7/?format=json","name":"Linux network development","link_name":"netdev","list_id":"netdev.vger.kernel.org","list_email":"netdev@vger.kernel.org","web_url":null,"scm_url":null,"webscm_url":null,"list_archive_url":"","list_archive_url_format":"","commit_url_format":""},"msgid":"<20170903042117.28923-16-saeedm@mellanox.com>","list_archive_url":null,"date":"2017-09-03T04:21:15","name":"[net-next,15/17] net/mlx5e: Use kernel's mechanism to avoid missing NAPIs","commit_ref":null,"pull_url":null,"state":"accepted","archived":true,"hash":"5aadc3305c64c7381e21256c05bf51c8d315e943","submitter":{"id":65299,"url":"http://patchwork.ozlabs.org/api/people/65299/?format=json","name":"Saeed Mahameed","email":"saeedm@mellanox.com"},"delegate":{"id":34,"url":"http://patchwork.ozlabs.org/api/users/34/?format=json","username":"davem","first_name":"David","last_name":"Miller","email":"davem@davemloft.net"},"mbox":"http://patchwork.ozlabs.org/project/netdev/patch/20170903042117.28923-16-saeedm@mellanox.com/mbox/","series":[{"id":1196,"url":"http://patchwork.ozlabs.org/api/series/1196/?format=json","web_url":"http://patchwork.ozlabs.org/project/netdev/list/?series=1196","date":"2017-09-03T04:21:09","name":"[net-next,01/17] net/mlx5e: Reorganize struct mlx5e_rq","version":1,"mbox":"http://patchwork.ozlabs.org/series/1196/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/809200/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/809200/checks/","tags":{},"related":[],"headers":{"Return-Path":"","X-Original-To":"patchwork-incoming@ozlabs.org","Delivered-To":"patchwork-incoming@ozlabs.org","Authentication-Results":"ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; helo=vger.kernel.org;\n\tenvelope-from=netdev-owner@vger.kernel.org;\n\treceiver=)","Received":["from vger.kernel.org (vger.kernel.org [209.132.180.67])\n\tby ozlabs.org (Postfix) with ESMTP id 3xlKZd2NCsz9s7C\n\tfor ;\n\tSun, 3 Sep 2017 14:22:33 +1000 (AEST)","(majordomo@vger.kernel.org) by vger.kernel.org via listexpand\n\tid S1751764AbdICEW3 (ORCPT );\n\tSun, 3 Sep 2017 00:22:29 -0400","from mail-il-dmz.mellanox.com ([193.47.165.129]:60146 \"EHLO\n\tmellanox.co.il\" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org\n\twith ESMTP id S1751528AbdICEWQ (ORCPT\n\t); Sun, 3 Sep 2017 00:22:16 -0400","from Internal Mail-Server by MTLPINE1 (envelope-from\n\tsaeedm@mellanox.com)\n\twith ESMTPS (AES256-SHA encrypted); 3 Sep 2017 07:22:06 +0300","from sws.mtl.labs.mlnx (reg-l-vrt-045-015.mtl.labs.mlnx\n\t[10.135.45.15])\n\tby labmailer.mlnx (8.13.8/8.13.8) with ESMTP id v834M5lG017672;\n\tSun, 3 Sep 2017 07:22:06 +0300"],"From":"Saeed Mahameed ","To":"\"David S. Miller\" ","Cc":"netdev@vger.kernel.org, kernel-team@fb.com,\n\tTariq Toukan , Eric Dumazet ,\n\tSaeed Mahameed ","Subject":"[net-next 15/17] net/mlx5e: Use kernel's mechanism to avoid missing\n\tNAPIs","Date":"Sun, 3 Sep 2017 07:21:15 +0300","Message-Id":"<20170903042117.28923-16-saeedm@mellanox.com>","X-Mailer":"git-send-email 2.13.0","In-Reply-To":"<20170903042117.28923-1-saeedm@mellanox.com>","References":"<20170903042117.28923-1-saeedm@mellanox.com>","Sender":"netdev-owner@vger.kernel.org","Precedence":"bulk","List-ID":"","X-Mailing-List":"netdev@vger.kernel.org"},"content":"From: Tariq Toukan \n\nWe used a channel state bit MLX5E_CHANNEL_NAPI_SCHED to make\nsure no NAPI is missed when a channel's napi_schedule() is called\nfor completion events of the different channel's resources/rings\nwhile NAPI is currently running.\nNow, as similar mechanism is implemented in kernel,\n(\"39e6c8208d7b net: solve a NAPI race\"),\nwe obsolete our own implementation and rely on the return value\nof napi_complete_done().\n\nThis patch removes a redundant overhead of atomic bit operations.\n\nSigned-off-by: Tariq Toukan \nCc: Eric Dumazet \nSigned-off-by: Saeed Mahameed \n---\n drivers/net/ethernet/mellanox/mlx5/core/en.h | 5 -----\n drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 1 -\n drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c | 10 +---------\n 3 files changed, 1 insertion(+), 15 deletions(-)","diff":"diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h\nindex 9c0c07ffe557..7c046ae8b18e 100644\n--- a/drivers/net/ethernet/mellanox/mlx5/core/en.h\n+++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h\n@@ -570,10 +570,6 @@ struct mlx5e_rq {\n \tstruct mlx5_core_mkey umr_mkey;\n } ____cacheline_aligned_in_smp;\n \n-enum channel_flags {\n-\tMLX5E_CHANNEL_NAPI_SCHED = 1,\n-};\n-\n struct mlx5e_channel {\n \t/* data path */\n \tstruct mlx5e_rq rq;\n@@ -585,7 +581,6 @@ struct mlx5e_channel {\n \tstruct net_device *netdev;\n \t__be32 mkey_be;\n \tu8 num_tc;\n-\tunsigned long flags;\n \n \t/* control */\n \tstruct mlx5e_priv *priv;\ndiff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c\nindex 2da2ea222aaa..b2f689ec0d72 100644\n--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c\n+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c\n@@ -3697,7 +3697,6 @@ static int mlx5e_xdp_set(struct net_device *netdev, struct bpf_prog *prog)\n \n \t\tset_bit(MLX5E_RQ_STATE_ENABLED, &c->rq.state);\n \t\t/* napi_schedule in case we have missed anything */\n-\t\tset_bit(MLX5E_CHANNEL_NAPI_SCHED, &c->flags);\n \t\tnapi_schedule(&c->napi);\n \n \t\tif (old_prog)\ndiff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c\nindex 439ba1f2ffbc..92d9aa1cddd6 100644\n--- a/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c\n+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c\n@@ -40,8 +40,6 @@ int mlx5e_napi_poll(struct napi_struct *napi, int budget)\n \tint work_done;\n \tint i;\n \n-\tclear_bit(MLX5E_CHANNEL_NAPI_SCHED, &c->flags);\n-\n \tfor (i = 0; i < c->num_tc; i++)\n \t\tbusy |= mlx5e_poll_tx_cq(&c->sq[i].cq, budget);\n \n@@ -56,13 +54,8 @@ int mlx5e_napi_poll(struct napi_struct *napi, int budget)\n \tif (busy)\n \t\treturn budget;\n \n-\tnapi_complete_done(napi, work_done);\n-\n-\t/* avoid losing completion event during/after polling cqs */\n-\tif (test_bit(MLX5E_CHANNEL_NAPI_SCHED, &c->flags)) {\n-\t\tnapi_schedule(napi);\n+\tif (unlikely(!napi_complete_done(napi, work_done)))\n \t\treturn work_done;\n-\t}\n \n \tfor (i = 0; i < c->num_tc; i++)\n \t\tmlx5e_cq_arm(&c->sq[i].cq);\n@@ -81,7 +74,6 @@ void mlx5e_completion_event(struct mlx5_core_cq *mcq)\n \tstruct mlx5e_cq *cq = container_of(mcq, struct mlx5e_cq, mcq);\n \n \tcq->event_ctr++;\n-\tset_bit(MLX5E_CHANNEL_NAPI_SCHED, &cq->channel->flags);\n \tnapi_schedule(cq->napi);\n }\n \n","prefixes":["net-next","15/17"]}