From nobody Mon Jun 29 18:40:32 2026 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 7C522C433F5 for ; Thu, 3 Feb 2022 17:41:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352991AbiBCRlW (ORCPT ); Thu, 3 Feb 2022 12:41:22 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46292 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239435AbiBCRlO (ORCPT ); Thu, 3 Feb 2022 12:41:14 -0500 Received: from mail-wm1-x333.google.com (mail-wm1-x333.google.com [IPv6:2a00:1450:4864:20::333]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9F1D7C06173D for ; Thu, 3 Feb 2022 09:41:14 -0800 (PST) Received: by mail-wm1-x333.google.com with SMTP id j5-20020a05600c1c0500b0034d2e956aadso2258681wms.4 for ; Thu, 03 Feb 2022 09:41:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=m/kvsV2Fw6mBqvpDjxp3WYmDCchAjKBAAZ5SIZ3OfkM=; b=HSHMAONT3deohB+I/1UzVSnGmWqMvf0TxOrRDOPXl8HIJP1aLazsZcbqKflRKAvb2A R2z/8/lvXFscxa41tBF8xizb6oVHc6dxTYqNI80uIyYqKkXZGOoZ2he5zeWTk0Ld3XYE tJJPFb2EPPL+r/6FT2s4ofAZb1kJCKsXQ1GU7uJx4shOWROF9uNmf/AZu8bamDoehVPq s/YegMHV0i9lzc+3r3tTXZsCbmj1ImMa2BqCAukz/lPEs7X8z2JWkEJFAvT/CAWIj1cX 5s4dGh9HV8r7TOZt4cjo5xbqm6eNQiTd6ogQyCQelxppN67Y2b8ELsu7B+X+tYZr9jji nyHg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=m/kvsV2Fw6mBqvpDjxp3WYmDCchAjKBAAZ5SIZ3OfkM=; b=p9EMG6rqQhvBuYTo+LL8gKxTyX+nP7b+w8WuwQ9JEe3BRs3K933WkdTiMjzRupHq1D J3xOHYvBT/1eeIICf7wB4dbvIl/S1W14m/9MD1te/FBNrslDNi2gK9V/pCDwV0ijZe2/ hh5t1Km0dvJdXvDhlpeVTPk8cNcBD4rEKh3T1FLOyVMZP0jgzPTqvVHOGGNNriObTQyG BoJbeG8GJ7uFfvpmQhguubOxr0pA4u7ZQqB9iC2ap0mLa2sL1CuD7NXs8ZQ+I7WRyIS1 p2CEzNHgUhGwsOVH4RRAYdB/3vyxkCI40VA3LO7yy0kFsi25Q3Yv/JeDHDrSCchi6OXv mLEA== X-Gm-Message-State: AOAM53280DLdXgU6EBv/hyLdzx51RLxahgwRm5wX8CKDxqcwRzkvPOmP OVg0097pSbqWyAI+nncQ+otJg1oU6CiNyg== X-Google-Smtp-Source: ABdhPJwWFRMw0lDUQQC1/c9xp6DLHWvF0Qfeqznn5fUQXhGw/hQhtPgHachc3tQSajCxF+5JhCLOQQ== X-Received: by 2002:a05:600c:218:: with SMTP id 24mr11612148wmi.95.1643910073272; Thu, 03 Feb 2022 09:41:13 -0800 (PST) Received: from usaari01.cust.communityfibre.co.uk ([2a02:6b6d:f804:0:28c2:5854:c832:e580]) by smtp.gmail.com with ESMTPSA id r2sm10166178wmq.24.2022.02.03.09.41.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 03 Feb 2022 09:41:12 -0800 (PST) From: Usama Arif To: io-uring@vger.kernel.org, axboe@kernel.dk, asml.silence@gmail.com, linux-kernel@vger.kernel.org Cc: fam.zheng@bytedance.com, Usama Arif Subject: [PATCH v3 1/3] io_uring: remove trace for eventfd Date: Thu, 3 Feb 2022 17:41:06 +0000 Message-Id: <20220203174108.668549-2-usama.arif@bytedance.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220203174108.668549-1-usama.arif@bytedance.com> References: <20220203174108.668549-1-usama.arif@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" The information on whether eventfd is registered is not very useful and would result in the tracepoint being enclosed in an rcu_readlock in a later patch that tries to avoid ring quiesce for registering eventfd. Suggested-by: Jens Axboe Signed-off-by: Usama Arif --- fs/io_uring.c | 3 +-- include/trace/events/io_uring.h | 13 +++++-------- 2 files changed, 6 insertions(+), 10 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 2e04f718319d..21531609a9c6 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -11171,8 +11171,7 @@ SYSCALL_DEFINE4(io_uring_register, unsigned int, fd= , unsigned int, opcode, mutex_lock(&ctx->uring_lock); ret =3D __io_uring_register(ctx, opcode, arg, nr_args); mutex_unlock(&ctx->uring_lock); - trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_buf= s, - ctx->cq_ev_fd !=3D NULL, ret); + trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_buf= s, ret); out_fput: fdput(f); return ret; diff --git a/include/trace/events/io_uring.h b/include/trace/events/io_urin= g.h index 7346f0164cf4..098beda7601a 100644 --- a/include/trace/events/io_uring.h +++ b/include/trace/events/io_uring.h @@ -57,10 +57,9 @@ TRACE_EVENT(io_uring_create, * @opcode: describes which operation to perform * @nr_user_files: number of registered files * @nr_user_bufs: number of registered buffers - * @cq_ev_fd: whether eventfs registered or not * @ret: return code * - * Allows to trace fixed files/buffers/eventfds, that could be registered = to + * Allows to trace fixed files/buffers, that could be registered to * avoid an overhead of getting references to them for every operation. Th= is * event, together with io_uring_file_get, can provide a full picture of h= ow * much overhead one can reduce via fixing. @@ -68,16 +67,15 @@ TRACE_EVENT(io_uring_create, TRACE_EVENT(io_uring_register, =20 TP_PROTO(void *ctx, unsigned opcode, unsigned nr_files, - unsigned nr_bufs, bool eventfd, long ret), + unsigned nr_bufs, long ret), =20 - TP_ARGS(ctx, opcode, nr_files, nr_bufs, eventfd, ret), + TP_ARGS(ctx, opcode, nr_files, nr_bufs, ret), =20 TP_STRUCT__entry ( __field( void *, ctx ) __field( unsigned, opcode ) __field( unsigned, nr_files ) __field( unsigned, nr_bufs ) - __field( bool, eventfd ) __field( long, ret ) ), =20 @@ -86,14 +84,13 @@ TRACE_EVENT(io_uring_register, __entry->opcode =3D opcode; __entry->nr_files =3D nr_files; __entry->nr_bufs =3D nr_bufs; - __entry->eventfd =3D eventfd; __entry->ret =3D ret; ), =20 TP_printk("ring %p, opcode %d, nr_user_files %d, nr_user_bufs %d, " - "eventfd %d, ret %ld", + "ret %ld", __entry->ctx, __entry->opcode, __entry->nr_files, - __entry->nr_bufs, __entry->eventfd, __entry->ret) + __entry->nr_bufs, __entry->ret) ); =20 /** --=20 2.25.1 From nobody Mon Jun 29 18:40:32 2026 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 3C557C433EF for ; Thu, 3 Feb 2022 17:41:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352980AbiBCRlZ (ORCPT ); Thu, 3 Feb 2022 12:41:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46300 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1352962AbiBCRlP (ORCPT ); Thu, 3 Feb 2022 12:41:15 -0500 Received: from mail-wm1-x32c.google.com (mail-wm1-x32c.google.com [IPv6:2a00:1450:4864:20::32c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 92F67C061714 for ; Thu, 3 Feb 2022 09:41:15 -0800 (PST) Received: by mail-wm1-x32c.google.com with SMTP id 83so1445392wmc.1 for ; Thu, 03 Feb 2022 09:41:15 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=aQIq64tbZTT3r2lCTTr4R6nk7XQ2BemxKkJ9jTfWYWY=; b=J9b3Mh2dhIqNB/LNgDXyEUo+TLMDSnIbwyIsvwGHbK21Tz9yzTQiFM88EIUzsDtnyw +kJIL+/UhIAEh12lAuaWX5nXKdl392Nay9xMHSMN8FWT3NVstd0zl2UJTnCUzgUG2Fmy fUJOyYZYBsT1EYfs5pN255zXG0DaCG57y55c53U4aBE1VsGXjEewIBrt2tb0WaZXLmrJ o4JUxew5KFCFSoMEgrc20fMp7LcGDet+FIrpdMM3AkYkNyMiZY3LBDV/DPRh6Wn99ADO j8WNjeNvIyaLLfYcHxX5EXNUywoCyCJnpzV64g43lDER990XZ2zi8yQLhK66Ab1u/m6l rMZQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=aQIq64tbZTT3r2lCTTr4R6nk7XQ2BemxKkJ9jTfWYWY=; b=sISBRi84erIGY0O8GekI+qmP2/iPeEW4zOpHwgi1QJtetZpy8yukIFr+Fauvs7Y7FQ AOju5MXq4ZDMnwfSjB3C4pHGBdcdLc5YBgyJt5Clquz1mwr+f69IOaVQkCvxoF9JelG1 G36+xg1gI/bLb9nAyXKh2pIwKJ6h3TxP1ygg7NQnPo9bSpTwfodDVHSlVFJw5KIEK2Av MX4cSIBbfnJd9P+gSdgEXw2kGIAJAQ8x7Axa6VeEBHfAu492E/uSY2kcp6uwMJEy4jlu wxomr9LypZCg7nIAwz1mf38h96XzdvjA6jTBXgROWk2EuFOmHyPj+p6Ff3bQ9ZpCW3Lx NKYA== X-Gm-Message-State: AOAM530t/58DmhXGVBbATBXwFNQTWk2PtG7U+18ZLCK7KmC4NAPmew0+ zbimEo2OuLZ9U7Gz0PiI9CBdkw== X-Google-Smtp-Source: ABdhPJwZvfTpAjDtXMHfz+Tu1VG07UcHqWgt8rGdJH5n89L9VDk4GhL25DuWPfFzuC0OQb3pPCbGag== X-Received: by 2002:a05:600c:3ac5:: with SMTP id d5mr10996921wms.107.1643910074221; Thu, 03 Feb 2022 09:41:14 -0800 (PST) Received: from usaari01.cust.communityfibre.co.uk ([2a02:6b6d:f804:0:28c2:5854:c832:e580]) by smtp.gmail.com with ESMTPSA id r2sm10166178wmq.24.2022.02.03.09.41.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 03 Feb 2022 09:41:13 -0800 (PST) From: Usama Arif To: io-uring@vger.kernel.org, axboe@kernel.dk, asml.silence@gmail.com, linux-kernel@vger.kernel.org Cc: fam.zheng@bytedance.com, Usama Arif Subject: [PATCH v3 2/3] io_uring: avoid ring quiesce while registering/unregistering eventfd Date: Thu, 3 Feb 2022 17:41:07 +0000 Message-Id: <20220203174108.668549-3-usama.arif@bytedance.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220203174108.668549-1-usama.arif@bytedance.com> References: <20220203174108.668549-1-usama.arif@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" This is done by creating a new RCU data structure (io_ev_fd) as part of io_ring_ctx that holds the eventfd_ctx. The function io_eventfd_signal is executed under rcu_read_lock with a single rcu_dereference to io_ev_fd so that if another thread unregisters the eventfd while io_eventfd_signal is still being executed, the eventfd_signal for which io_eventfd_signal was called completes successfully. The process of registering/unregistering eventfd is done under a lock so multiple threads don't enter a race condition while registering/unregistering eventfd. With the above approach ring quiesce can be avoided which is much more expensive then using RCU lock. On the system tested, io_uring_reigster with IORING_REGISTER_EVENTFD takes less than 1ms with RCU lock, compared to 15ms before with ring quiesce. Signed-off-by: Usama Arif --- fs/io_uring.c | 91 +++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 66 insertions(+), 25 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 21531609a9c6..47d48020ae27 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -326,6 +326,10 @@ struct io_submit_state { struct blk_plug plug; }; =20 +struct io_ev_fd { + struct eventfd_ctx *cq_ev_fd; +}; + struct io_ring_ctx { /* const or read-mostly hot data */ struct { @@ -399,7 +403,8 @@ struct io_ring_ctx { struct { unsigned cached_cq_tail; unsigned cq_entries; - struct eventfd_ctx *cq_ev_fd; + struct io_ev_fd __rcu *io_ev_fd; + struct mutex ev_fd_lock; struct wait_queue_head cq_wait; unsigned cq_extra; atomic_t cq_timeouts; @@ -1448,6 +1453,7 @@ static __cold struct io_ring_ctx *io_ring_ctx_alloc(s= truct io_uring_params *p) xa_init_flags(&ctx->io_buffers, XA_FLAGS_ALLOC1); xa_init_flags(&ctx->personalities, XA_FLAGS_ALLOC1); mutex_init(&ctx->uring_lock); + mutex_init(&ctx->ev_fd_lock); init_waitqueue_head(&ctx->cq_wait); spin_lock_init(&ctx->completion_lock); spin_lock_init(&ctx->timeout_lock); @@ -1726,13 +1732,24 @@ static inline struct io_uring_cqe *io_get_cqe(struc= t io_ring_ctx *ctx) return &rings->cqes[tail & mask]; } =20 -static inline bool io_should_trigger_evfd(struct io_ring_ctx *ctx) +static void io_eventfd_signal(struct io_ring_ctx *ctx) { - if (likely(!ctx->cq_ev_fd)) - return false; + struct io_ev_fd *ev_fd; + + rcu_read_lock(); + /* rcu_dereference ctx->io_ev_fd once and use it for both for checking an= d eventfd_signal */ + ev_fd =3D rcu_dereference(ctx->io_ev_fd); + + if (likely(!ev_fd)) + goto out; if (READ_ONCE(ctx->rings->cq_flags) & IORING_CQ_EVENTFD_DISABLED) - return false; - return !ctx->eventfd_async || io_wq_current_is_worker(); + goto out; + + if (!ctx->eventfd_async || io_wq_current_is_worker()) + eventfd_signal(ev_fd->cq_ev_fd, 1); + +out: + rcu_read_unlock(); } =20 /* @@ -1751,8 +1768,7 @@ static void io_cqring_ev_posted(struct io_ring_ctx *c= tx) */ if (wq_has_sleeper(&ctx->cq_wait)) wake_up_all(&ctx->cq_wait); - if (io_should_trigger_evfd(ctx)) - eventfd_signal(ctx->cq_ev_fd, 1); + io_eventfd_signal(ctx); } =20 static void io_cqring_ev_posted_iopoll(struct io_ring_ctx *ctx) @@ -1764,8 +1780,7 @@ static void io_cqring_ev_posted_iopoll(struct io_ring= _ctx *ctx) if (waitqueue_active(&ctx->cq_wait)) wake_up_all(&ctx->cq_wait); } - if (io_should_trigger_evfd(ctx)) - eventfd_signal(ctx->cq_ev_fd, 1); + io_eventfd_signal(ctx); } =20 /* Returns true if there are no backlogged entries after the flush */ @@ -9353,35 +9368,59 @@ static int __io_sqe_buffers_update(struct io_ring_c= tx *ctx, =20 static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg) { + struct io_ev_fd *ev_fd; __s32 __user *fds =3D arg; - int fd; + int fd, ret; =20 - if (ctx->cq_ev_fd) - return -EBUSY; + mutex_lock(&ctx->ev_fd_lock); + ret =3D -EBUSY; + if (rcu_dereference_protected(ctx->io_ev_fd, lockdep_is_held(&ctx->ev_fd_= lock))) + goto out; =20 + ret =3D -EFAULT; if (copy_from_user(&fd, fds, sizeof(*fds))) - return -EFAULT; + goto out; =20 - ctx->cq_ev_fd =3D eventfd_ctx_fdget(fd); - if (IS_ERR(ctx->cq_ev_fd)) { - int ret =3D PTR_ERR(ctx->cq_ev_fd); + ret =3D -ENOMEM; + ev_fd =3D kmalloc(sizeof(*ev_fd), GFP_KERNEL); + if (!ev_fd) + goto out; =20 - ctx->cq_ev_fd =3D NULL; - return ret; + ev_fd->cq_ev_fd =3D eventfd_ctx_fdget(fd); + if (IS_ERR(ev_fd->cq_ev_fd)) { + ret =3D PTR_ERR(ev_fd->cq_ev_fd); + kfree(ev_fd); + goto out; } =20 - return 0; + rcu_assign_pointer(ctx->io_ev_fd, ev_fd); + ret =3D 0; + +out: + mutex_unlock(&ctx->ev_fd_lock); + return ret; } =20 static int io_eventfd_unregister(struct io_ring_ctx *ctx) { - if (ctx->cq_ev_fd) { - eventfd_ctx_put(ctx->cq_ev_fd); - ctx->cq_ev_fd =3D NULL; - return 0; + struct io_ev_fd *ev_fd; + int ret; + + mutex_lock(&ctx->ev_fd_lock); + ev_fd =3D rcu_dereference_protected(ctx->io_ev_fd, lockdep_is_held(&ctx->= ev_fd_lock)); + if (!ev_fd) { + ret =3D -ENXIO; + goto out; } + synchronize_rcu(); + eventfd_ctx_put(ev_fd->cq_ev_fd); + kfree(ev_fd); + rcu_assign_pointer(ctx->io_ev_fd, NULL); + ret =3D 0; =20 - return -ENXIO; +out: + mutex_unlock(&ctx->ev_fd_lock); + return ret; } =20 static void io_destroy_buffers(struct io_ring_ctx *ctx) @@ -10960,6 +10999,8 @@ static bool io_register_op_must_quiesce(int op) case IORING_REGISTER_FILES: case IORING_UNREGISTER_FILES: case IORING_REGISTER_FILES_UPDATE: + case IORING_REGISTER_EVENTFD: + case IORING_UNREGISTER_EVENTFD: case IORING_REGISTER_PROBE: case IORING_REGISTER_PERSONALITY: case IORING_UNREGISTER_PERSONALITY: --=20 2.25.1 From nobody Mon Jun 29 18:40:32 2026 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 3F33AC433FE for ; Thu, 3 Feb 2022 17:41:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1353000AbiBCRl2 (ORCPT ); Thu, 3 Feb 2022 12:41:28 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46308 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236163AbiBCRlQ (ORCPT ); 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Thu, 03 Feb 2022 09:41:14 -0800 (PST) From: Usama Arif To: io-uring@vger.kernel.org, axboe@kernel.dk, asml.silence@gmail.com, linux-kernel@vger.kernel.org Cc: fam.zheng@bytedance.com, Usama Arif Subject: [PATCH v3 3/3] io_uring: avoid ring quiesce for IORING_REGISTER_EVENTFD_ASYNC Date: Thu, 3 Feb 2022 17:41:08 +0000 Message-Id: <20220203174108.668549-4-usama.arif@bytedance.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220203174108.668549-1-usama.arif@bytedance.com> References: <20220203174108.668549-1-usama.arif@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" This is done using the RCU data structure (io_ev_fd). eventfd_async is moved from io_ring_ctx to io_ev_fd which is RCU protected hence avoiding ring quiesce which is much more expensive than an RCU lock. Signed-off-by: Usama Arif --- fs/io_uring.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 47d48020ae27..25ed86533910 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -328,6 +328,7 @@ struct io_submit_state { =20 struct io_ev_fd { struct eventfd_ctx *cq_ev_fd; + unsigned int eventfd_async: 1; }; =20 struct io_ring_ctx { @@ -339,7 +340,6 @@ struct io_ring_ctx { unsigned int flags; unsigned int compat: 1; unsigned int drain_next: 1; - unsigned int eventfd_async: 1; unsigned int restricted: 1; unsigned int off_timeout_used: 1; unsigned int drain_active: 1; @@ -1745,7 +1745,7 @@ static void io_eventfd_signal(struct io_ring_ctx *ctx) if (READ_ONCE(ctx->rings->cq_flags) & IORING_CQ_EVENTFD_DISABLED) goto out; =20 - if (!ctx->eventfd_async || io_wq_current_is_worker()) + if (!ev_fd->eventfd_async || io_wq_current_is_worker()) eventfd_signal(ev_fd->cq_ev_fd, 1); =20 out: @@ -9366,7 +9366,8 @@ static int __io_sqe_buffers_update(struct io_ring_ctx= *ctx, return done ? done : err; } =20 -static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg) +static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg, + unsigned int eventfd_async) { struct io_ev_fd *ev_fd; __s32 __user *fds =3D arg; @@ -9392,6 +9393,7 @@ static int io_eventfd_register(struct io_ring_ctx *ct= x, void __user *arg) kfree(ev_fd); goto out; } + ev_fd->eventfd_async =3D eventfd_async; =20 rcu_assign_pointer(ctx->io_ev_fd, ev_fd); ret =3D 0; @@ -11000,6 +11002,7 @@ static bool io_register_op_must_quiesce(int op) case IORING_UNREGISTER_FILES: case IORING_REGISTER_FILES_UPDATE: case IORING_REGISTER_EVENTFD: + case IORING_REGISTER_EVENTFD_ASYNC: case IORING_UNREGISTER_EVENTFD: case IORING_REGISTER_PROBE: case IORING_REGISTER_PERSONALITY: @@ -11100,17 +11103,16 @@ static int __io_uring_register(struct io_ring_ctx= *ctx, unsigned opcode, ret =3D io_register_files_update(ctx, arg, nr_args); break; case IORING_REGISTER_EVENTFD: - case IORING_REGISTER_EVENTFD_ASYNC: ret =3D -EINVAL; if (nr_args !=3D 1) break; - ret =3D io_eventfd_register(ctx, arg); - if (ret) + ret =3D io_eventfd_register(ctx, arg, 0); + break; + case IORING_REGISTER_EVENTFD_ASYNC: + ret =3D -EINVAL; + if (nr_args !=3D 1) break; - if (opcode =3D=3D IORING_REGISTER_EVENTFD_ASYNC) - ctx->eventfd_async =3D 1; - else - ctx->eventfd_async =3D 0; + ret =3D io_eventfd_register(ctx, arg, 1); break; case IORING_UNREGISTER_EVENTFD: ret =3D -EINVAL; --=20 2.25.1