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=-12.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED,USER_AGENT_GIT 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 C5A8DC4363D for ; Thu, 24 Sep 2020 02:51:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8576A23119 for ; Thu, 24 Sep 2020 02:51:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726414AbgIXCvp (ORCPT ); Wed, 23 Sep 2020 22:51:45 -0400 Received: from out30-44.freemail.mail.aliyun.com ([115.124.30.44]:45729 "EHLO out30-44.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726281AbgIXCvp (ORCPT ); Wed, 23 Sep 2020 22:51:45 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R481e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04420;MF=joseph.qi@linux.alibaba.com;NM=1;PH=DS;RN=3;SR=0;TI=SMTPD_---0U9v3MqP_1600915902; Received: from localhost(mailfrom:joseph.qi@linux.alibaba.com fp:SMTPD_---0U9v3MqP_1600915902) by smtp.aliyun-inc.com(127.0.0.1); Thu, 24 Sep 2020 10:51:42 +0800 From: Joseph Qi To: Jens Axboe Cc: io-uring , Xiaoguang Wang Subject: [PATCH] io_uring: show sqthread pid and cpu in fdinfo Date: Thu, 24 Sep 2020 10:51:42 +0800 Message-Id: <1600915902-15143-1-git-send-email-joseph.qi@linux.alibaba.com> X-Mailer: git-send-email 1.8.3.1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org In most cases we'll specify IORING_SETUP_SQPOLL and run multiple io_uring instances in a host. Since all sqthreads are named "io_uring-sq", it's hard to distinguish the relations between application process and its io_uring sqthread. With this patch, application can get its corresponding sqthread pid and cpu through show_fdinfo. Steps: 1. Get io_uring fd first. $ ls -l /proc//fd | grep -w io_uring 2. Then get io_uring instance related info, including corresponding sqthread pid and cpu. $ cat /proc//fdinfo/ pos: 0 flags: 02000002 mnt_id: 13 SqThread: 6929 SqThreadCpu: 2 UserFiles: 1 0: testfile UserBufs: 0 PollList: Signed-off-by: Joseph Qi --- 1. Go to upstream/4.9/4.19？(N) 2. Backport from upstream？(N) 3. Summarized pre-commmit testing in Aone (Y) 4. Aone URL (https://aone.alibaba-inc.com/task/29517834) 5. Use CONFIG_xxx ? (N) 6. Use sysfs or boot parameter to turn off code changes? (N) 7. Any kernel-userspace API/ABI changes? (N) 8. I have full maintenance commitments for my 50+ code changes (Y) fs/io_uring.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/io_uring.c b/fs/io_uring.c index c718ac0..5171de0 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -7934,6 +7934,10 @@ static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m) int i; mutex_lock(&ctx->uring_lock); + seq_printf(m, "SqThread:\t%d\n", (ctx->flags & IORING_SETUP_SQPOLL) ? + task_pid_nr(ctx->sqo_thread) : -1); + seq_printf(m, "SqThreadCpu:\t%d\n", (ctx->flags & IORING_SETUP_SQPOLL) ? + task_cpu(ctx->sqo_thread) : -1); seq_printf(m, "UserFiles:\t%u\n", ctx->nr_user_files); for (i = 0; i < ctx->nr_user_files; i++) { struct fixed_file_table *table; -- 1.8.3.1