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=-6.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_SANE_1 autolearn=no 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 2FDA6C433F5 for ; Thu, 16 Sep 2021 06:29:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 11A8F611CE for ; Thu, 16 Sep 2021 06:29:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234580AbhIPGbH (ORCPT ); Thu, 16 Sep 2021 02:31:07 -0400 Received: from out30-54.freemail.mail.aliyun.com ([115.124.30.54]:37882 "EHLO out30-54.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234579AbhIPGbH (ORCPT ); Thu, 16 Sep 2021 02:31:07 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R171e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04407;MF=haoxu@linux.alibaba.com;NM=1;PH=DS;RN=4;SR=0;TI=SMTPD_---0UoYh8xZ_1631773785; Received: from B-25KNML85-0107.local(mailfrom:haoxu@linux.alibaba.com fp:SMTPD_---0UoYh8xZ_1631773785) by smtp.aliyun-inc.com(127.0.0.1); Thu, 16 Sep 2021 14:29:45 +0800 Subject: Re: [PATCH] io_uring: add more uring info to fdinfo for debug To: Jens Axboe , Pavel Begunkov Cc: io-uring@vger.kernel.org, Joseph Qi References: <20210913130854.38542-1-haoxu@linux.alibaba.com> <3ecf6b05-e92d-7d74-8f72-983ec0d790fc@kernel.dk> <655da9c2-1926-370b-06f8-8e744111f3a7@kernel.dk> From: Hao Xu Message-ID: <60bfddf8-d19a-102e-21dc-bf4ea7bf9724@linux.alibaba.com> Date: Thu, 16 Sep 2021 14:29:45 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.13.0 MIME-Version: 1.0 In-Reply-To: <655da9c2-1926-370b-06f8-8e744111f3a7@kernel.dk> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org 在 2021/9/15 下午11:32, Jens Axboe 写道: > On 9/15/21 9:31 AM, Pavel Begunkov wrote: >> On 9/15/21 4:26 PM, Jens Axboe wrote: >>> On 9/13/21 7:08 AM, Hao Xu wrote: >>>> Developers may need some uring info to help themselves debug and address >>>> issues, these info includes sqring/cqring head/tail and the detail >>>> sqe/cqe info, which is very useful when it stucks. >>> >>> I think this is a good addition, more info to help you debug a stuck case >>> is always good. I'll queue this up for 5.16. >> >> Are there limits how much we can print? I remember people were couldn't >> even show a list of CPUs (was it proc?). The overflow list may be huge. > > It's using seq_file, so I _think_ we should be fine here. Not sure when/if > it truncates. > It seems the default buf size of seq_file is PAGE_SIZE.