From nobody Wed Sep 17 05:38:58 2025 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 BBC9CC3DA7D for ; Thu, 22 Dec 2022 15:06:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235924AbiLVPGj (ORCPT ); Thu, 22 Dec 2022 10:06:39 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52792 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235885AbiLVPGR (ORCPT ); Thu, 22 Dec 2022 10:06:17 -0500 Received: from out162-62-57-210.mail.qq.com (out162-62-57-210.mail.qq.com [162.62.57.210]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4C6EC2253A; Thu, 22 Dec 2022 07:06:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foxmail.com; s=s201512; t=1671721564; bh=qWvhPFkxHOCw18z6l8gnbRxNK5NNo+0WZuA+FGjUVJo=; h=From:To:Cc:Subject:Date; b=iCHCuIlDGueNA+LavRIq2LscZn8zHFg/Ondq1gq6K+4Azaasqq+HUCqkFaDz7z7VJ Vtv4/2wBT8kUg6EGO3DLAv9IPA4C8khelfxoCJSt85bog9mY7IZmolPIA9sssr934T Hn49yo4S6rjQsG0LUnqVhK/cePBKSg7tprVMxUGQ= Received: from wen-VirtualBox.lan ([222.182.118.246]) by newxmesmtplogicsvrsza2-0.qq.com (NewEsmtp) with SMTP id 180A06B2; Thu, 22 Dec 2022 23:06:00 +0800 X-QQ-mid: xmsmtpt1671721560txq9dgjgs Message-ID: X-QQ-XMAILINFO: MR/iVh5QLeieZhEVUGBRfdeskQHM+wLLc6O0DDT56u6OXEDqKbv/OCJieHhgG+ R4ZP76y2PVchPdP70r94/V8Bm6jfLZdrwuV2mlJW3EFWWNYaVEyXeTc0RKkEyTAXl304mB8wD+hx zSnOhqPfHmRGLMS+9QE1Ind8z+XXyw97XtHY6ieqSzFRZIm9mFPYrC8ACxA9dU45SVoIALUP/tHR Rry7avhQoB3G3s7yar3cI3IDnbLNCkUaf3maEfFAGsNbT38BvXkgbN2fbhFR6TPMiaKJ922vW84/ 2Gwtcl63xzc/QlUqCj6ymr9wam+vpFvU97CwmkFI5E9ZorlQvouR1UGbM2BvhLG/SPw7pQthRoKY hiz5zMWpc+DrG5QdU1jSwH5YjejNqMZvpquo6X73fUxtzIGi/c6/B57tmW1jRMp7LyhkE1cismsw A7985Gl54dAqpBkm4Gj7t9/v5g4tdm0hRoPrTZUzaMfHZMLcs3Um0iIzL0jPxCOQGW1AXgYWv/zm 92O1xosZ0zWJYIJ0FFr5MTOlVB0HO27cZsbhEgutFr0+DgPbhDK9I6uIXsizlzgCWplc1cjR4Kov 398cPUsMVdx6OYpaMJrTz6S8/pmHuH3gegIw4duOMLYjYyXlXfnzIQXXVhhfH6PGh0L4P/0qHbTn wbyjbtngAY3WVb00D0YLTyvnJyMZhm/pNEpuGmtMshlGo1ZI2xCEhyB6OfsNX8jdkwY+H0DWBLyE nEywgkmbnhmOKklXKl6Ox9yaZe3kcYhHsQHqvujXYR6YQdTVdIT30upQrXxlBtIEMuYssaNgSs0h ELRM0izRcYyuW80X/P/EE6OQx/Tli46BWHiC6LWiOaHt5GjBSjnUlJoJI46ieWqX7/Rx0T022qij qRpA9JfZM8iYxGYOcaaWMp4ERBGw0h5r96nezi1TvLz7CzIBgFpQoAFLFNF/CAmT7FxbVybbMQiX cib1tQ0vY37DU/mJIMR7C9o2ODJcHDQeG/JcWXBW2lGYjvDGwX3CmbkPQqCZ0XSP8ePWJJmM1vZ5 hjRCHPFgCPhFWcCmRsTR9cKlUsj2q112qBUNfplA== From: wenyang.linux@foxmail.com To: Alexander Viro Cc: Wen Yang , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] eventfd: use a generic helper instead of an open coded wait_event Date: Thu, 22 Dec 2022 23:05:52 +0800 X-OQ-MSGID: <20221222150552.190999-1-wenyang.linux@foxmail.com> X-Mailer: git-send-email 2.25.1 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" From: Wen Yang Use wait_event_interruptible_locked_irq() in the eventfd_{write,read} to avoid the longer, open coded equivalent. Signed-off-by: Wen Yang Cc: Alexander Viro Cc: linux-fsdevel@vger.kernel.org Cc: linux-kernel@vger.kernel.org --- fs/eventfd.c | 43 +++++++------------------------------------ 1 file changed, 7 insertions(+), 36 deletions(-) diff --git a/fs/eventfd.c b/fs/eventfd.c index 249ca6c0b784..5ff944a17d6d 100644 --- a/fs/eventfd.c +++ b/fs/eventfd.c @@ -228,7 +228,6 @@ static ssize_t eventfd_read(struct kiocb *iocb, struct = iov_iter *to) struct file *file =3D iocb->ki_filp; struct eventfd_ctx *ctx =3D file->private_data; __u64 ucnt =3D 0; - DECLARE_WAITQUEUE(wait, current); =20 if (iov_iter_count(to) < sizeof(ucnt)) return -EINVAL; @@ -239,23 +238,9 @@ static ssize_t eventfd_read(struct kiocb *iocb, struct= iov_iter *to) spin_unlock_irq(&ctx->wqh.lock); return -EAGAIN; } - __add_wait_queue(&ctx->wqh, &wait); - for (;;) { - set_current_state(TASK_INTERRUPTIBLE); - if (ctx->count) - break; - if (signal_pending(current)) { - __remove_wait_queue(&ctx->wqh, &wait); - __set_current_state(TASK_RUNNING); - spin_unlock_irq(&ctx->wqh.lock); - return -ERESTARTSYS; - } - spin_unlock_irq(&ctx->wqh.lock); - schedule(); - spin_lock_irq(&ctx->wqh.lock); - } - __remove_wait_queue(&ctx->wqh, &wait); - __set_current_state(TASK_RUNNING); + + if (wait_event_interruptible_locked_irq(ctx->wqh, ctx->count)) + return -ERESTARTSYS; } eventfd_ctx_do_read(ctx, &ucnt); current->in_eventfd =3D 1; @@ -275,7 +260,6 @@ static ssize_t eventfd_write(struct file *file, const c= har __user *buf, size_t c struct eventfd_ctx *ctx =3D file->private_data; ssize_t res; __u64 ucnt; - DECLARE_WAITQUEUE(wait, current); =20 if (count < sizeof(ucnt)) return -EINVAL; @@ -288,23 +272,10 @@ static ssize_t eventfd_write(struct file *file, const= char __user *buf, size_t c if (ULLONG_MAX - ctx->count > ucnt) res =3D sizeof(ucnt); else if (!(file->f_flags & O_NONBLOCK)) { - __add_wait_queue(&ctx->wqh, &wait); - for (res =3D 0;;) { - set_current_state(TASK_INTERRUPTIBLE); - if (ULLONG_MAX - ctx->count > ucnt) { - res =3D sizeof(ucnt); - break; - } - if (signal_pending(current)) { - res =3D -ERESTARTSYS; - break; - } - spin_unlock_irq(&ctx->wqh.lock); - schedule(); - spin_lock_irq(&ctx->wqh.lock); - } - __remove_wait_queue(&ctx->wqh, &wait); - __set_current_state(TASK_RUNNING); + res =3D wait_event_interruptible_locked_irq(ctx->wqh, + ULLONG_MAX - ctx->count > ucnt); + if (!res) + res =3D sizeof(ucnt); } if (likely(res > 0)) { ctx->count +=3D ucnt; --=20 2.25.1