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=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_NEOMUTT 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 4806AECDFBB for ; Sat, 21 Jul 2018 17:21:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E5A4E20854 for ; Sat, 21 Jul 2018 17:21:30 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E5A4E20854 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=stgolabs.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727949AbeGUSOx (ORCPT ); Sat, 21 Jul 2018 14:14:53 -0400 Received: from mx2.suse.de ([195.135.220.15]:56626 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727483AbeGUSOx (ORCPT ); Sat, 21 Jul 2018 14:14:53 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id C32E6AE5B; Sat, 21 Jul 2018 17:21:26 +0000 (UTC) Date: Sat, 21 Jul 2018 10:21:20 -0700 From: Davidlohr Bueso To: Andrew Morton Cc: jbaron@akamai.com, viro@zeniv.linux.org.uk, linux-kernel@vger.kernel.org, Peter Zijlstra Subject: Re: [PATCH -next 0/2] fs/epoll: loosen irq safety when possible Message-ID: <20180721172120.kbdu4euc2wn4xzgf@linux-r8p5> References: <20180720172956.2883-1-dave@stgolabs.net> <20180720124212.7260d76d83e2b8e5e3349ea5@linux-foundation.org> <20180720200559.27nc7j2rrxpy5p3n@linux-r8p5> <20180720134429.1ba61018934b084bb2e17bdb@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20180720134429.1ba61018934b084bb2e17bdb@linux-foundation.org> User-Agent: NeoMutt/20170912 (1.9.0) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 20 Jul 2018, Andrew Morton wrote: >We could open-code it locally. Add a couple of >WARN_ON_ONCE(irqs_disabled())? That might need re-benchmarking with >Xen but surely just reading the thing isn't too expensive? We could also pass on the responsibility to lockdep and just use lockdep_assert_irqs_disabled(). But I guess that would be less effective than to just open code it in epoll without lockdep -- note that over 80 places in the kernel do this. Thanks, Davidlohr