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 03865E732FE for ; Thu, 28 Sep 2023 17:25:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231953AbjI1RZe (ORCPT ); Thu, 28 Sep 2023 13:25:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40138 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231899AbjI1RZa (ORCPT ); Thu, 28 Sep 2023 13:25:30 -0400 Received: from mail-ej1-x629.google.com (mail-ej1-x629.google.com [IPv6:2a00:1450:4864:20::629]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0FAC9193 for ; Thu, 28 Sep 2023 10:25:28 -0700 (PDT) Received: by mail-ej1-x629.google.com with SMTP id a640c23a62f3a-9a1bcc540c0so349161366b.1 for ; Thu, 28 Sep 2023 10:25:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1695921925; x=1696526725; darn=vger.kernel.org; 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=V5m39pK9Sy+s98BPtXb5MPOzqgjCaZT2iuuWI0t83mc=; b=UmGn9vNMxK9jugw5FvQnqmL2r2OvneHLTQSMVl4f3jMHvuA2Ew1YUyytyPRZ7T/9us H70B+rUVCpoJxfiwxL1JYnvlxcyHLIfduBMdirJ527MxqTdLkQMb0HgOxnlNH4pYSqP6 V/9k2GSH4fYxywb7P2YEx0bkE3BLAzDRs7dr+EY3K95rvzr3y36PP/tpIEbDyfd3dwIl XmEK5M9+xS9ETvc+7YC0pfR+b5SkgicoOsHlNGyX6gxwcyptzCmYrkXIGoK3/OfKqvXa ZB4ZDgozqrOZxc3r30N/OaaX6Pum0VDRIM8SIUxz5qnps23HqLTYvEsdT1jpg9EypSDe 1YEA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695921925; x=1696526725; 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=V5m39pK9Sy+s98BPtXb5MPOzqgjCaZT2iuuWI0t83mc=; b=A5JvXVH6TnghyL/WnN/6U3SCZKuIueYvJnqIX9HO94SsE10SIYBIYxvpatIinOrl6j tKE+uKz2KQPMC8bQEwinHXrkqmdR/e6QL7D/mkBK53nfa/XUJMGjP7RnX+e5qw5q+s9x QxVcOVeIozrZ7rqZBzU3ajL+//wbTVjvC5P1HVx+cHqNotN32LvE9wcNAX8B1WZ9ts8v 3X9GTf7VvCd2vZD3cparTowocp6pwhWmIcP3bxZ6EfwkF+IPpaxxYEfSG2LNYDo0wis8 K2Knatv5XFY1cYFBR2O/XooKEf+Hq85LhPP2iiL1+4QccV4v5e5086bCDlvC1Yw1zA4i sNiw== X-Gm-Message-State: AOJu0YxwM7b3Om6lJKLAwka2N58iNHh209gDqmutuJV+gBMo0ZNT0h1d 8rJ0XNbYw6/HQx412q+pvzsRX5CDz/OmIveH4g8S5E0j X-Google-Smtp-Source: AGHT+IGt+eNuwg2/AQcW7COtq95twqR233dKHl8Ir5zXd8GhVMetP/XHQdKO6YrKNkPd+D/OTtsq8A== X-Received: by 2002:a17:906:9f05:b0:9b2:b532:d8d7 with SMTP id fy5-20020a1709069f0500b009b2b532d8d7mr1832832ejc.5.1695921925707; Thu, 28 Sep 2023 10:25:25 -0700 (PDT) Received: from localhost.localdomain ([45.147.210.162]) by smtp.gmail.com with ESMTPSA id j17-20020a170906279100b0099329b3ab67sm11151788ejc.71.2023.09.28.10.25.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 28 Sep 2023 10:25:24 -0700 (PDT) From: Jens Axboe To: io-uring@vger.kernel.org, linux-kernel@vger.kernel.org Cc: peterz@infradead.org, andres@anarazel.de, tglx@linutronix.de, Jens Axboe Subject: [PATCH 2/8] futex: factor out the futex wake handling Date: Thu, 28 Sep 2023 11:25:11 -0600 Message-Id: <20230928172517.961093-3-axboe@kernel.dk> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230928172517.961093-1-axboe@kernel.dk> References: <20230928172517.961093-1-axboe@kernel.dk> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org In preparation for having another waker that isn't futex_wake_mark(), add a wake handler in futex_q. No extra data is associated with the handler outside of struct futex_q itself. futex_wake_mark() is defined as the standard wakeup helper, now set through futex_q_init like other defaults. Normal sync futex waiting relies on wake_q holding tasks that should be woken up. This is what futex_wake_mark() does, it'll unqueue the futex and add the associated task to the wake queue. For async usage of futex waiting, rather than having tasks sleeping on the futex, we'll need to deal with a futex wake differently. For the planned io_uring case, that means posting a completion event for the task in question. Having a definable wake handler can help support that use case. Signed-off-by: Jens Axboe --- kernel/futex/futex.h | 5 +++++ kernel/futex/requeue.c | 3 ++- kernel/futex/waitwake.c | 6 +++--- 3 files changed, 10 insertions(+), 4 deletions(-) diff --git a/kernel/futex/futex.h b/kernel/futex/futex.h index a173a9d501e1..547f509b2c87 100644 --- a/kernel/futex/futex.h +++ b/kernel/futex/futex.h @@ -139,11 +139,15 @@ struct futex_pi_state { union futex_key key; } __randomize_layout; +struct futex_q; +typedef void (futex_wake_fn)(struct wake_q_head *wake_q, struct futex_q *q); + /** * struct futex_q - The hashed futex queue entry, one per waiting task * @list: priority-sorted list of tasks waiting on this futex * @task: the task waiting on the futex * @lock_ptr: the hash bucket lock + * @wake: the wake handler for this queue * @key: the key the futex is hashed on * @pi_state: optional priority inheritance state * @rt_waiter: rt_waiter storage for use with requeue_pi @@ -168,6 +172,7 @@ struct futex_q { struct task_struct *task; spinlock_t *lock_ptr; + futex_wake_fn *wake; union futex_key key; struct futex_pi_state *pi_state; struct rt_mutex_waiter *rt_waiter; diff --git a/kernel/futex/requeue.c b/kernel/futex/requeue.c index a0a79954f506..9dc789399a1a 100644 --- a/kernel/futex/requeue.c +++ b/kernel/futex/requeue.c @@ -58,6 +58,7 @@ enum { const struct futex_q futex_q_init = { /* list gets initialized in futex_queue()*/ + .wake = futex_wake_mark, .key = FUTEX_KEY_INIT, .bitset = FUTEX_BITSET_MATCH_ANY, .requeue_state = ATOMIC_INIT(Q_REQUEUE_PI_NONE), @@ -593,7 +594,7 @@ int futex_requeue(u32 __user *uaddr1, unsigned int flags1, /* Plain futexes just wake or requeue and are done */ if (!requeue_pi) { if (++task_count <= nr_wake) - futex_wake_mark(&wake_q, this); + this->wake(&wake_q, this); else requeue_futex(this, hb1, hb2, &key2); continue; diff --git a/kernel/futex/waitwake.c b/kernel/futex/waitwake.c index 37860f794bf7..35c6a637a4bb 100644 --- a/kernel/futex/waitwake.c +++ b/kernel/futex/waitwake.c @@ -177,7 +177,7 @@ int futex_wake(u32 __user *uaddr, unsigned int flags, int nr_wake, u32 bitset) if (!(this->bitset & bitset)) continue; - futex_wake_mark(&wake_q, this); + this->wake(&wake_q, this); if (++ret >= nr_wake) break; } @@ -292,7 +292,7 @@ int futex_wake_op(u32 __user *uaddr1, unsigned int flags, u32 __user *uaddr2, ret = -EINVAL; goto out_unlock; } - futex_wake_mark(&wake_q, this); + this->wake(&wake_q, this); if (++ret >= nr_wake) break; } @@ -306,7 +306,7 @@ int futex_wake_op(u32 __user *uaddr1, unsigned int flags, u32 __user *uaddr2, ret = -EINVAL; goto out_unlock; } - futex_wake_mark(&wake_q, this); + this->wake(&wake_q, this); if (++op_ret >= nr_wake2) break; } -- 2.40.1