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 X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 17E7DC10F00 for ; Wed, 27 Mar 2019 08:20:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E9A052082F for ; Wed, 27 Mar 2019 08:20:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732371AbfC0IUU (ORCPT ); Wed, 27 Mar 2019 04:20:20 -0400 Received: from mx1.redhat.com ([209.132.183.28]:50944 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726176AbfC0IUR (ORCPT ); Wed, 27 Mar 2019 04:20:17 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 1133681E06; Wed, 27 Mar 2019 08:20:17 +0000 (UTC) Received: from carbon (ovpn-200-46.brq.redhat.com [10.40.200.46]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3A94362660; Wed, 27 Mar 2019 08:20:12 +0000 (UTC) Date: Wed, 27 Mar 2019 09:20:11 +0100 From: Jesper Dangaard Brouer To: Heiner Kallweit Cc: Edward Cree , "netdev@vger.kernel.org" , brouer@redhat.com Subject: Re: netif_receive_skb_list and interrupts enabled/disabled Message-ID: <20190327092011.0fded74d@carbon> In-Reply-To: <5c170def-4c09-8da2-e0cd-6fc29881031f@gmail.com> References: <5c170def-4c09-8da2-e0cd-6fc29881031f@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Wed, 27 Mar 2019 08:20:17 +0000 (UTC) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Tue, 26 Mar 2019 21:04:09 +0100 Heiner Kallweit wrote: > A question inspired by 0a25d92c6f4f ("dpaa2-eth: use netif_receive_skb_list"): > kerneldoc of netif_receive_skb_list states that interrupts should be > enabled. Do notice that the exact same comment (and rule) applies to netif_receive_skb() which also have below comment: /* [...] * This function may only be called from softirq context and interrupts * should be enabled. */ > When used from NAPI context irqs typically are disabled. > And if the NAPI budget is fully consumed then interrupts don't get enabled > in the same NAPI poll loop. How is this supposed to play together? You have misunderstood that is means that interrupts should be enabled. It is talking about local_irq_disable/enable and local_irq_save/restore. This is different from disabling the IRQs on a given NIC RX-queue. -- Best regards, Jesper Dangaard Brouer MSc.CS, Principal Kernel Engineer at Red Hat LinkedIn: http://www.linkedin.com/in/brouer