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=-16.9 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, USER_AGENT_SANE_1 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 7F1FAC433EF for ; Wed, 15 Sep 2021 13:01:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 57ADE6103B for ; Wed, 15 Sep 2021 13:01:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229670AbhIONDM (ORCPT ); Wed, 15 Sep 2021 09:03:12 -0400 Received: from out30-56.freemail.mail.aliyun.com ([115.124.30.56]:39187 "EHLO out30-56.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233238AbhIONDM (ORCPT ); Wed, 15 Sep 2021 09:03:12 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R151e4;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_---0UoUEQ0N_1631710911; Received: from B-25KNML85-0107.local(mailfrom:haoxu@linux.alibaba.com fp:SMTPD_---0UoUEQ0N_1631710911) by smtp.aliyun-inc.com(127.0.0.1); Wed, 15 Sep 2021 21:01:51 +0800 Subject: Re: [PATCH] io_uring: add more uring info to fdinfo for debug From: Hao Xu To: Jens Axboe Cc: io-uring@vger.kernel.org, Pavel Begunkov , Joseph Qi References: <20210913130854.38542-1-haoxu@linux.alibaba.com> Message-ID: Date: Wed, 15 Sep 2021 21:01:51 +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: <20210913130854.38542-1-haoxu@linux.alibaba.com> 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 ping... 在 2021/9/13 下午9:08, Hao Xu 写道: > 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. > > Signed-off-by: Hao Xu > --- > fs/io_uring.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++---- > 1 file changed, 55 insertions(+), 4 deletions(-) > > diff --git a/fs/io_uring.c b/fs/io_uring.c > index f795ad281038..ac048592a3e8 100644 > --- a/fs/io_uring.c > +++ b/fs/io_uring.c > @@ -9950,8 +9950,48 @@ static int io_uring_show_cred(struct seq_file *m, unsigned int id, > static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m) > { > struct io_sq_data *sq = NULL; > + struct io_overflow_cqe *ocqe; > + struct io_rings *r = ctx->rings; > + unsigned int sq_mask = ctx->sq_entries - 1, cq_mask = ctx->cq_entries - 1; > + unsigned int cached_sq_head = ctx->cached_sq_head; > + unsigned int cached_cq_tail = ctx->cached_cq_tail; > + unsigned int sq_head = READ_ONCE(r->sq.head); > + unsigned int sq_tail = READ_ONCE(r->sq.tail); > + unsigned int cq_head = READ_ONCE(r->cq.head); > + unsigned int cq_tail = READ_ONCE(r->cq.tail); > bool has_lock; > - int i; > + unsigned int i; > + > + /* > + * we may get imprecise sqe and cqe info if uring is actively running > + * since we get cached_sq_head and cached_cq_tail without uring_lock > + * and sq_tail and cq_head are changed by userspace. But it's ok since > + * we usually use these info when it is stuck. > + */ > + seq_printf(m, "SqHead:\t%u\n", sq_head & sq_mask); > + seq_printf(m, "SqTail:\t%u\n", sq_tail & sq_mask); > + seq_printf(m, "CachedSqHead:\t%u\n", cached_sq_head & sq_mask); > + seq_printf(m, "CqHead:\t%u\n", cq_head & cq_mask); > + seq_printf(m, "CqTail:\t%u\n", cq_tail & cq_mask); > + seq_printf(m, "CachedCqTail:\t%u\n", cached_cq_tail & cq_mask); > + seq_printf(m, "SQEs:\t%u\n", sq_tail - cached_sq_head); > + for (i = cached_sq_head; i < sq_tail; i++) { > + unsigned int sq_idx = READ_ONCE(ctx->sq_array[i & sq_mask]); > + > + if (likely(sq_idx <= sq_mask)) { > + struct io_uring_sqe *sqe = &ctx->sq_sqes[sq_idx]; > + > + seq_printf(m, "%5u: opcode:%d, fd:%d, flags:%x, user_data:%llu\n", > + sq_idx, sqe->opcode, sqe->fd, sqe->flags, sqe->user_data); > + } > + } > + seq_printf(m, "CQEs:\t%u\n", cached_cq_tail - cq_head); > + for (i = cq_head; i < cached_cq_tail; i++) { > + struct io_uring_cqe *cqe = &r->cqes[i & cq_mask]; > + > + seq_printf(m, "%5u: user_data:%llu, res:%d, flag:%x\n", > + i & cq_mask, cqe->user_data, cqe->res, cqe->flags); > + } > > /* > * Avoid ABBA deadlock between the seq lock and the io_uring mutex, > @@ -9993,7 +10033,10 @@ static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m) > xa_for_each(&ctx->personalities, index, cred) > io_uring_show_cred(m, index, cred); > } > - seq_printf(m, "PollList:\n"); > + if (has_lock) > + mutex_unlock(&ctx->uring_lock); > + > + seq_puts(m, "PollList:\n"); > spin_lock(&ctx->completion_lock); > for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) { > struct hlist_head *list = &ctx->cancel_hash[i]; > @@ -10003,9 +10046,17 @@ static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m) > seq_printf(m, " op=%d, task_works=%d\n", req->opcode, > req->task->task_works != NULL); > } > + > + seq_puts(m, "CqOverflowList:\n"); > + list_for_each_entry(ocqe, &ctx->cq_overflow_list, list) { > + struct io_uring_cqe *cqe = &ocqe->cqe; > + > + seq_printf(m, " user_data=%llu, res=%d, flags=%x\n", > + cqe->user_data, cqe->res, cqe->flags); > + > + } > + > spin_unlock(&ctx->completion_lock); > - if (has_lock) > - mutex_unlock(&ctx->uring_lock); > } > > static void io_uring_show_fdinfo(struct seq_file *m, struct file *f) >