From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 22777C64ED6 for ; Sun, 26 Feb 2023 14:59:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231590AbjBZO67 (ORCPT ); Sun, 26 Feb 2023 09:58:59 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54128 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231374AbjBZO5Z (ORCPT ); Sun, 26 Feb 2023 09:57:25 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0AE1418B3A; Sun, 26 Feb 2023 06:52:11 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id CB1DBB80B48; Sun, 26 Feb 2023 14:51:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7D7E0C433D2; Sun, 26 Feb 2023 14:51:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1677423114; bh=zkU74y7MifVYlqtCKQ4t0bXX0MZUaEbHtIg+4QY1zpM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YVgy0i3mbZZh8yO7U66Vgb32hDuPSW+ZcEOwgnAQf/0feRr+Q5LSvw5cpBmDROUC/ 2ZT0RhHhSf4lW+WtjykyGMtrKvYjxFKxtQVlgUJs1Rcf3DWXV4AraIDRZBSzK8a59J Pw24SwvXIYg5pSkCRNCzdVE6inmvYRQbn+vPr5Karas2XuYLiZ7ZOxaepTbCdMUkiF I34MZoJV4Xy/9xJ0gk2TmuwaX1zxMxE6qdN5yKcARZ8I/uy9aTdEdIsIRY+dO5f701 Hdgkd4g5/h7PV8fMBGy0iXboTrQA0MHJDBf4P+Oz2evOTS+TW4aNIm6DGcriYc07n7 vgwKCZqB8vhVw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Breno Leitao , Michael van der Westhuizen , Jakub Kicinski , Sasha Levin , davem@davemloft.net, edumazet@google.com, pabeni@redhat.com, wsa+renesas@sang-engineering.com, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 11/19] netpoll: Remove 4s sleep during carrier detection Date: Sun, 26 Feb 2023 09:51:13 -0500 Message-Id: <20230226145123.829229-11-sashal@kernel.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230226145123.829229-1-sashal@kernel.org> References: <20230226145123.829229-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Breno Leitao [ Upstream commit d8afe2f8a92d2aac3df645772f6ee61b0b2fc147 ] This patch removes the msleep(4s) during netpoll_setup() if the carrier appears instantly. Here are some scenarios where this workaround is counter-productive in modern ages: Servers which have BMC communicating over NC-SI via the same NIC as gets used for netconsole. BMC will keep the PHY up, hence the carrier appearing instantly. The link is fibre, SERDES getting sync could happen within 0.1Hz, and the carrier also appears instantly. Other than that, if a driver is reporting instant carrier and then losing it, this is probably a driver bug. Reported-by: Michael van der Westhuizen Signed-off-by: Breno Leitao Link: https://lore.kernel.org/r/20230125185230.3574681-1-leitao@debian.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/core/netpoll.c | 12 +----------- 1 file changed, 1 insertion(+), 11 deletions(-) diff --git a/net/core/netpoll.c b/net/core/netpoll.c index 78bbb912e5025..0bf9db14cc336 100644 --- a/net/core/netpoll.c +++ b/net/core/netpoll.c @@ -674,7 +674,7 @@ int netpoll_setup(struct netpoll *np) } if (!netif_running(ndev)) { - unsigned long atmost, atleast; + unsigned long atmost; np_info(np, "device %s not up yet, forcing it\n", np->dev_name); @@ -686,7 +686,6 @@ int netpoll_setup(struct netpoll *np) } rtnl_unlock(); - atleast = jiffies + HZ/10; atmost = jiffies + carrier_timeout * HZ; while (!netif_carrier_ok(ndev)) { if (time_after(jiffies, atmost)) { @@ -696,15 +695,6 @@ int netpoll_setup(struct netpoll *np) msleep(1); } - /* If carrier appears to come up instantly, we don't - * trust it and pause so that we don't pump all our - * queued console messages into the bitbucket. - */ - - if (time_before(jiffies, atleast)) { - np_notice(np, "carrier detect appears untrustworthy, waiting 4 seconds\n"); - msleep(4000); - } rtnl_lock(); } -- 2.39.0