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 7ECE1C433F5 for ; Mon, 27 Dec 2021 06:14:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235279AbhL0GOZ (ORCPT ); Mon, 27 Dec 2021 01:14:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53572 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235267AbhL0GOY (ORCPT ); Mon, 27 Dec 2021 01:14:24 -0500 Received: from mail-qv1-xf2f.google.com (mail-qv1-xf2f.google.com [IPv6:2607:f8b0:4864:20::f2f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EE98BC06173E; Sun, 26 Dec 2021 22:14:23 -0800 (PST) Received: by mail-qv1-xf2f.google.com with SMTP id ke6so13111690qvb.1; Sun, 26 Dec 2021 22:14:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=u+dFE/6V8YlZA37R5EdGCSZl3b3izh9waYOV/+DOAiA=; b=NsfVTUuMS5ai5U7Nu3Zn7Bv1nmgI3lW5RlCQ3w2GrHEt4XzxF8qtx3r6DphwBZZkU/ d5UcoeYma6ORy+kdBdGcMdJ3y8oY4mwShj5xnG/1KdS3+WbI1qd0iAq1rVKIk08EWXwk A4YcUcwdhard8raSsODxopTShJuqXUWpGunTuJxFI2KIAhrGk9EaGeEzYTrU+PMxM+Kx 0dnCUGPIgHwRR46WPlS61nErsnswoBORn8L42YApvmRWh2TZVuM7YttAfThRvb7ylwt8 Fr9vy0eHYSnTmoIMZW+pcK8Aaer1nklqfHs3i4iHd0WZuQ0VkGYwcn0YexVW2xsfKREl eaqg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=u+dFE/6V8YlZA37R5EdGCSZl3b3izh9waYOV/+DOAiA=; b=OCFWYPIBqMJR2BS16sRYvugEUYRYIJjIy6gg3RENcADlA/1tiiUnfXfjeiSWBBZPyd CbX+9aaq62VPSbedxIT/fLQhMmsS0wj9bYAGymGuphLKNkAljl5BhfPu31e/jVGVjqIg wBxfln7kGtFEw7hi0gFZZG0GRqfIc7KoWUsPo6rrFbLjGvU7OULv7j7vrp1E1MfmRdEo XXCV5N6UFxSMsd0Fdd+IN3OCWENlPYqkaiM2fAq8Fl19yN+U43fB5/DVQgTvdbUKTDUp 3mwbPSLH9kHTZCKrmXYXTJ5pv/EQk2vmI0/cv3PXlMEgdeEO9mmlyk5RRq67zGeHdy0Q 1JtA== X-Gm-Message-State: AOAM533AWHsYLlfoK+A0mGW3cXQY0fzSWjpiY6mrpM8RSxGWdtOalnvJ hKPvyo+ZY7fMg3sqRvZuECUwIk/6pP0vORmO1U2L3oTeMJAG9A== X-Google-Smtp-Source: ABdhPJzwfbXmQgXhLB2hjSWy9HTlJXt0fphlDMkgtleB2CJzEiDIT995tXIPrpdaTfkRSS54/ns6c1sIVRpZk0nAMqQ= X-Received: by 2002:ad4:5aac:: with SMTP id u12mr10003470qvg.105.1640585662738; Sun, 26 Dec 2021 22:14:22 -0800 (PST) MIME-Version: 1.0 References: <1640224567-3014-1-git-send-email-huangzhaoyang@gmail.com> <20211223091100.4a86188f@kicinski-fedora-PC1C0HJN.hsd1.ca.comcast.net> In-Reply-To: <20211223091100.4a86188f@kicinski-fedora-PC1C0HJN.hsd1.ca.comcast.net> From: Zhaoyang Huang Date: Mon, 27 Dec 2021 14:14:02 +0800 Message-ID: Subject: Re: [PATCH] net: remove judgement based on gfp_flags To: Jakub Kicinski Cc: "David S. Miller" , Zhaoyang Huang , netdev@vger.kernel.org, LKML Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 24, 2021 at 1:11 AM Jakub Kicinski wrote: > > On Thu, 23 Dec 2021 09:56:07 +0800 Huangzhaoyang wrote: > > From: Zhaoyang Huang > > > > The parameter allocation here is used for indicating if the memory > > allocation can stall or not. Since we have got the skb buffer, it > > doesn't make sense to check if we can yield on the net's congested > > via gfp_flags. Remove it now. > > This is checking if we can sleep AFAICT. What are you trying to fix? Yes and NO. gfp means *get free pages* which indicate if the embedded memory allocation among the process can sleep or not, but without any other meanings. The driver which invokes this function could have to use GFP_KERNEL for allocating memory as the critical resources but don't want to sleep on the netlink's congestion. > > > diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c > > index 4c57532..af5b6af 100644 > > --- a/net/netlink/af_netlink.c > > +++ b/net/netlink/af_netlink.c > > @@ -1526,7 +1526,7 @@ int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 portid, > > consume_skb(info.skb2); > > > > if (info.delivered) { > > - if (info.congested && gfpflags_allow_blocking(allocation)) > > + if (info.congested) > > yield(); > > return 0; > > } >