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,URIBL_BLOCKED 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 6317AC169C4 for ; Tue, 29 Jan 2019 20:35:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3A7D02087E for ; Tue, 29 Jan 2019 20:35:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727507AbfA2Ufc (ORCPT ); Tue, 29 Jan 2019 15:35:32 -0500 Received: from mx1.redhat.com ([209.132.183.28]:42122 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727075AbfA2Ufc (ORCPT ); Tue, 29 Jan 2019 15:35:32 -0500 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 0180080503; Tue, 29 Jan 2019 20:35:32 +0000 (UTC) Received: from segfault.boston.devel.redhat.com (segfault.boston.devel.redhat.com [10.19.60.26]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2BFF519062; Tue, 29 Jan 2019 20:35:31 +0000 (UTC) From: Jeff Moyer To: Jens Axboe Cc: Christoph Hellwig , linux-aio@kvack.org, linux-block@vger.kernel.org, linux-man@vger.kernel.org, linux-api@vger.kernel.org, avi@scylladb.com Subject: Re: [PATCH 07/18] io_uring: support for IO polling References: <20190128213538.13486-1-axboe@kernel.dk> <20190128213538.13486-8-axboe@kernel.dk> <20190129172414.GA15347@lst.de> X-PGP-KeyID: 1F78E1B4 X-PGP-CertKey: F6FE 280D 8293 F72C 65FD 5A58 1FF8 A7CA 1F78 E1B4 Date: Tue, 29 Jan 2019 15:35:30 -0500 In-Reply-To: (Jens Axboe's message of "Tue, 29 Jan 2019 12:10:08 -0700") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Tue, 29 Jan 2019 20:35:32 +0000 (UTC) Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Jens Axboe writes: > On 1/29/19 11:31 AM, Jens Axboe wrote: >>> The code looks a little clumsy to me. Why not: >>> >>> while (!list_empty(&ctx->poll_list)) { >>> int ret = io_do_iopoll(ctx, nr_events, min); >>> if (ret) >>> return ret; >>> >>> if (!min || *nr_events >= min) >>> return 0; >>> } >>> >>> return 1; >> >> I think you messed up the 0/1 here, how about this: >> >> while (!list_empty(&ctx->poll_list)) { >> int ret; >> >> ret = io_do_iopoll(ctx, nr_events, min); >> if (ret < 0) >> return ret; >> if (!min || *nr_events >= min) >> return 1; >> } >> >> return 0; > > Or I did... I think yours is correct. maybe document the return code? ;-) -Jeff