get:
Show a patch.

patch:
Update a patch.

put:
Update a patch.

GET /api/patches/809200/?format=api
HTTP 200 OK
Allow: GET, PUT, PATCH, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "id": 809200,
    "url": "http://patchwork.ozlabs.org/api/patches/809200/?format=api",
    "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=api",
        "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=api",
        "name": "Saeed Mahameed",
        "email": "saeedm@mellanox.com"
    },
    "delegate": {
        "id": 34,
        "url": "http://patchwork.ozlabs.org/api/users/34/?format=api",
        "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=api",
            "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": "<netdev-owner@vger.kernel.org>",
        "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=<UNKNOWN>)",
        "Received": [
            "from vger.kernel.org (vger.kernel.org [209.132.180.67])\n\tby ozlabs.org (Postfix) with ESMTP id 3xlKZd2NCsz9s7C\n\tfor <patchwork-incoming@ozlabs.org>;\n\tSun,  3 Sep 2017 14:22:33 +1000 (AEST)",
            "(majordomo@vger.kernel.org) by vger.kernel.org via listexpand\n\tid S1751764AbdICEW3 (ORCPT <rfc822;patchwork-incoming@ozlabs.org>);\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<rfc822;netdev@vger.kernel.org>); 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 <saeedm@mellanox.com>",
        "To": "\"David S. Miller\" <davem@davemloft.net>",
        "Cc": "netdev@vger.kernel.org, kernel-team@fb.com,\n\tTariq Toukan <tariqt@mellanox.com>, Eric Dumazet <edumazet@google.com>,\n\tSaeed Mahameed <saeedm@mellanox.com>",
        "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": "<netdev.vger.kernel.org>",
        "X-Mailing-List": "netdev@vger.kernel.org"
    },
    "content": "From: Tariq Toukan <tariqt@mellanox.com>\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 <tariqt@mellanox.com>\nCc: Eric Dumazet <edumazet@google.com>\nSigned-off-by: Saeed Mahameed <saeedm@mellanox.com>\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"
    ]
}