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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 43230C4708D for ; Wed, 7 Dec 2022 03:54:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229843AbiLGDyn (ORCPT ); Tue, 6 Dec 2022 22:54:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41618 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229829AbiLGDyl (ORCPT ); Tue, 6 Dec 2022 22:54:41 -0500 Received: from mail-ed1-x536.google.com (mail-ed1-x536.google.com [IPv6:2a00:1450:4864:20::536]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D93E352158 for ; Tue, 6 Dec 2022 19:54:40 -0800 (PST) Received: by mail-ed1-x536.google.com with SMTP id e13so23144085edj.7 for ; Tue, 06 Dec 2022 19:54:40 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=r5fgO8A8lvZ98Yk+tc8eOFrqMx1DtgiAeuBltW/yuOA=; b=mNyRTWAGsag5ljFZSekhTerSRx48o8RQeSDc449OmHrp18NxwHe129CrQJH+hi6dU0 pRc7tLDOx2LAEMHA+hLaQHOm68hGqft6/vHnM6+Ha60fzk135CTaUICAglpvD9UuCO0u FRFLcBpznBV1LGkyO1BFsTyq0HaNLs7yqDYlVHZArrF/s/PFCT5bCZ7hUJJH5SarxkKg rmn7QPcRMd2K8X4Iv+FP7hjOZvUT+dVN8RarQzluuwyz8+pThYJPgJ5Jripu/bNrFEaU Ssmzp8d3Uqya1lfvlKmBtWwGUEv6jGOqbbEu5Vn9QcRSls56X//7LBP86cQ/evZ3v4mz 6J5g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=r5fgO8A8lvZ98Yk+tc8eOFrqMx1DtgiAeuBltW/yuOA=; b=qKcTpg083qxNIpZvxD3m6Vb1ERstiqf9aHm3Go3Hb2ZUNvcBNHDbkKNcig0QqqnbMb ayEYJwIfFU9IINXb/hkvSLzRLoipGhmZkXWeR9AREP15X6CJrIse+uVPcbKBxjYq4Wu3 vvDZBJru6EK7X5hFfWTeLxrl6osYz9hDrptxm90RsxnyxFMOMZN5ZfPW75lEaCGZGjOI ZDj5MBkJ+CiuX6ne8AW/7Sn0OKOYEh91wA0K7ibQJyG6HhLzAP4Z3PtIGHBRt8OrxaRW KOj0pwogCy+AbfuMKQGF+pfC5U/Sldn2FTLoKmIdJBgn5Jh3CiJpAr4hYCqUKv8Jj753 51cQ== X-Gm-Message-State: ANoB5plaEhljU7+gi1Va5n+9Dv/dhd9QAhyChN+C6lL/8rLWkDQXtdfG D1BFJY3x6ivbWkHlRvzIzjWL3SxOj1A= X-Google-Smtp-Source: AA0mqf7dM3J636vTKokAE6NkXwDWARNABM005EFropR0+g4fqlcoTze3SMNXWR3vbnr3hydMCxBh1Q== X-Received: by 2002:a05:6402:548a:b0:468:e8e2:31c9 with SMTP id fg10-20020a056402548a00b00468e8e231c9mr14184891edb.310.1670385279242; Tue, 06 Dec 2022 19:54:39 -0800 (PST) Received: from 127.0.0.1localhost (94.196.241.58.threembb.co.uk. [94.196.241.58]) by smtp.gmail.com with ESMTPSA id 9-20020a170906210900b0073de0506745sm7938939ejt.197.2022.12.06.19.54.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 06 Dec 2022 19:54:39 -0800 (PST) From: Pavel Begunkov To: io-uring@vger.kernel.org Cc: Jens Axboe , asml.silence@gmail.com Subject: [PATCH for-next v2 08/12] io_uring: never run tw and fallback in parallel Date: Wed, 7 Dec 2022 03:53:33 +0000 Message-Id: <96f4987265c4312f376f206511c6af3e77aaf5ac.1670384893.git.asml.silence@gmail.com> X-Mailer: git-send-email 2.38.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Once we fallback a tw we want all requests to that task to be given to the fallback wq so we dont run it in parallel with the last, i.e. post PF_EXITING, tw run of the task. Signed-off-by: Pavel Begunkov --- io_uring/io_uring.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index 3a422a7b7132..0e424d8721ab 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -149,6 +149,7 @@ static void io_clean_op(struct io_kiocb *req); static void io_queue_sqe(struct io_kiocb *req); static void io_move_task_work_from_local(struct io_ring_ctx *ctx); static void __io_submit_flush_completions(struct io_ring_ctx *ctx); +static __cold void io_fallback_tw(struct io_uring_task *tctx); static struct kmem_cache *req_cachep; @@ -1160,10 +1161,17 @@ void tctx_task_work(struct callback_head *cb) struct io_uring_task *tctx = container_of(cb, struct io_uring_task, task_work); struct llist_node fake = {}; - struct llist_node *node = io_llist_xchg(&tctx->task_list, &fake); + struct llist_node *node; unsigned int loops = 1; - unsigned int count = handle_tw_list(node, &ctx, &uring_locked, NULL); + unsigned int count; + + if (unlikely(current->flags & PF_EXITING)) { + io_fallback_tw(tctx); + return; + } + node = io_llist_xchg(&tctx->task_list, &fake); + count = handle_tw_list(node, &ctx, &uring_locked, NULL); node = io_llist_cmpxchg(&tctx->task_list, &fake, NULL); while (node != &fake) { loops++; -- 2.38.1