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 8EDCDC4167B for ; Wed, 6 Dec 2023 17:39:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1442710AbjLFRjQ (ORCPT ); Wed, 6 Dec 2023 12:39:16 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48580 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1379728AbjLFRjO (ORCPT ); Wed, 6 Dec 2023 12:39:14 -0500 Received: from mail-pl1-x62f.google.com (mail-pl1-x62f.google.com [IPv6:2607:f8b0:4864:20::62f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B6328D47 for ; Wed, 6 Dec 2023 09:39:20 -0800 (PST) Received: by mail-pl1-x62f.google.com with SMTP id d9443c01a7336-1d08a924fcfso11285ad.2 for ; Wed, 06 Dec 2023 09:39:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=networkplumber-org.20230601.gappssmtp.com; s=20230601; t=1701884360; x=1702489160; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:subject:cc:to:from:date:from:to:cc:subject:date :message-id:reply-to; bh=epEPAoODqaSsyq6mWAsXlk/zwY3UQrTT5iMw4+zTkgU=; b=G7LjdyIBPxbsJPrlhEsc/+rcQEIDcADolRlDc0bxGGMoxV2At6voLXxW1WNg1sPigp ubDVSi4drL8F4IeGeN4cp7tKlL85UIPstQN+vSxODzRN8dQ/5WZeYyY4nqyPRkhxaVp8 3Om4T3p9ZrfI93wQVBqlH1w0yigioBPPlVtUMpALHSKtioytu53GIcjsLQtr0fsQsmr3 PxJCU90MYP02ZZ7aNCbhKM1/ju2pgzr+AEV7XqfNKMrW9PlvrgOPJQFJ/a4vrgOfpgd1 sy6cORbKKk5h8ygo1blZd440qABNaIyhZJmZNNKk8Iu8d6r/wdcEK0uHFvynwOQs1WEs Souw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1701884360; x=1702489160; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:subject:cc:to:from:date:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=epEPAoODqaSsyq6mWAsXlk/zwY3UQrTT5iMw4+zTkgU=; b=mi/M2lA9ERVpyweqR9vhqvH6u/Z9ErhvQL8Ny09m86fbK/OQD9kPCLCDqyvtOwUTt6 GrsCYQcvz9tVDXnsp2ZRjNWd9Spmy6iG7SBZHnE8MiSFRuIWBDj1KaJ8SL5b5MaVLvJo 10ObycK5iA9P/pW1Y5zfnmUiQmJQmnM5SmfHWSTTMUEcO8djBzEIhUso/dnLlsJ4+04A B93Tz+/SLLjqjuxSL4F7PGjwPVrkIyot8uUO17K4ZMKNj/SqHlyT9V5Kh03KsrjQI54m 0x3Tm9u+KkqvgIB5f4RbhIHPlKFPTNtA2i+W/P3Shwzjgv75+5doJfT6oDFyXmV2ezul UDSA== X-Gm-Message-State: AOJu0YwzmvP8F90iTc7e3wbuW7JYh8r8Ow6D0gsfzXhJu3X97UG30JU6 xxl8yczRyOK1MKP7fivFMbKPkA== X-Google-Smtp-Source: AGHT+IGVTG9OQEKtoS6pjPpVNzMPWylYXwUA5I/GkMnBeOoLO3QQ7WcBm26jNLVY5AwA6U/sTaSzSg== X-Received: by 2002:a17:902:8f8c:b0:1d0:6ffd:e2d7 with SMTP id z12-20020a1709028f8c00b001d06ffde2d7mr1069589plo.113.1701884360181; Wed, 06 Dec 2023 09:39:20 -0800 (PST) Received: from hermes.local (204-195-123-141.wavecable.com. [204.195.123.141]) by smtp.gmail.com with ESMTPSA id j5-20020a170902da8500b001cff353696asm81396plx.302.2023.12.06.09.39.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 06 Dec 2023 09:39:19 -0800 (PST) Date: Wed, 6 Dec 2023 09:39:17 -0800 From: Stephen Hemminger To: Judy Hsiao Cc: Eric Dumazet , David Ahern , Simon Horman , Douglas Anderson , Brian Haley , "David S. Miller" , Jakub Kicinski , Joel Granados , Julian Anastasov , Leon Romanovsky , Paolo Abeni , linux-kernel@vger.kernel.org, netdev@vger.kernel.org Subject: Re: [PATCH v2] neighbour: Don't let neigh_forced_gc() disable preemption for long Message-ID: <20231206093917.04fd57b5@hermes.local> In-Reply-To: <20231206033913.1290566-1-judyhsiao@chromium.org> References: <20231206033913.1290566-1-judyhsiao@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 6 Dec 2023 03:38:33 +0000 Judy Hsiao wrote: > diff --git a/net/core/neighbour.c b/net/core/neighbour.c > index df81c1f0a570..552719c3bbc3 100644 > --- a/net/core/neighbour.c > +++ b/net/core/neighbour.c > @@ -253,9 +253,11 @@ static int neigh_forced_gc(struct neigh_table *tbl) > { > int max_clean = atomic_read(&tbl->gc_entries) - > READ_ONCE(tbl->gc_thresh2); > + u64 tmax = ktime_get_ns() + NSEC_PER_MSEC; > unsigned long tref = jiffies - 5 * HZ; > struct neighbour *n, *tmp; > int shrunk = 0; > + int loop = 0; > > NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs); > > @@ -278,11 +280,16 @@ static int neigh_forced_gc(struct neigh_table *tbl) > shrunk++; > if (shrunk >= max_clean) > break; > + if (++loop == 16) { Overall looks good. Minor comments: - loop count should probably be unsigned - the magic constant 16 should be a sysctl tuneable