From patchwork Thu Sep 28 17:25:10 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 13403345 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 AF4CEE732FF for ; Thu, 28 Sep 2023 17:25:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231451AbjI1RZ2 (ORCPT ); Thu, 28 Sep 2023 13:25:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40100 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231489AbjI1RZ1 (ORCPT ); Thu, 28 Sep 2023 13:25:27 -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 1E0DB1B7 for ; Thu, 28 Sep 2023 10:25:26 -0700 (PDT) Received: by mail-ej1-x629.google.com with SMTP id a640c23a62f3a-9ae3d4c136fso335440466b.1 for ; Thu, 28 Sep 2023 10:25:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1695921924; x=1696526724; 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=wwcbO19kHoooGXVXpd3ZWHbtBSLBsnmpj+7juMc3wkU=; b=l6I6EJaiBTJeRurbO3Mibnbw4c7dcTayckAOEsk+pS32rJSu6FGyiAQnde4ixFsjyn NhxA2+1A922UurrqCH6aqjWiwF0TQL/G0uePsaukxAzYzH6N3mSU9+EUiZ2mn4S1Boeo UATV3oxi5RbnMAM2jgfk5W92jFRWnW1drRZzfjH8WIH2/PRluCh9hb+/+wpvpbB5Dlm/ 3z8qNdGssEw+ZVLgGNy6FvMwoZ7cerGuzTg5HamuzlPbVT30F8rHOb+kSoKeeW648gtz oWPHrYqYK5UoBzhk5qmvaGkCTNbyxMPH0ahjbz3B3Q0fIMeU/xaumzx0OxtJ88Lj6qLh 0Mug== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695921924; x=1696526724; 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=wwcbO19kHoooGXVXpd3ZWHbtBSLBsnmpj+7juMc3wkU=; b=rmlQxhAirLxh4lkY5qn4H+yoYtlO3F0nOYJbUzKrlLPqNqlDLLu5Oa3PbrFifh7trv x+nhKCeHAX00631wj6JFwUP65MlDmkQ3jljdSV0kqGL7TRjIDo+gsvacA6OA+o+CtYKS dN1f0Ixtn5UcE7jBOTuKYSOQQdx0OZojcLe176FIsHVtSAYtOkpVboa9OfczeahCFSYU GpcKZqkfIgl0U/2vCQFdsya3vwwKDCtOx0XXBrYoeyF1Dgf73M1cWF4VxoCpq4fVkY3V rjGDajPonYm4fow+BOz7NB/KWWGbtShRblV2IwLGnUtFFe6vLc0AUfjb3y917d9YaNfj MgKA== X-Gm-Message-State: AOJu0YxYy7oDRVoKVSaaoPKgnA0ETBuA5H52xzTiHVleAyIMmpEcehhv Ys6O4WrBQfC5fFnEn3iBR9NUxhLUt/lPprBojSUnEigm X-Google-Smtp-Source: AGHT+IH5PTU0ovSZZw4UQZLnYsvrY0gHgAqi1x1w4d5GG7gCr7v7vSaW+30EtCIFbXs7GRRlSsxM+w== X-Received: by 2002:a17:906:2258:b0:9ad:e66a:413f with SMTP id 24-20020a170906225800b009ade66a413fmr1695851ejr.3.1695921924096; Thu, 28 Sep 2023 10:25:24 -0700 (PDT) Received: from localhost.localdomain ([45.147.210.162]) by smtp.gmail.com with ESMTPSA id j17-20020a170906279100b0099329b3ab67sm11151788ejc.71.2023.09.28.10.25.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 28 Sep 2023 10:25:22 -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 1/8] futex: move FUTEX2_VALID_MASK to futex.h Date: Thu, 28 Sep 2023 11:25:10 -0600 Message-Id: <20230928172517.961093-2-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 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org We need this for validating the futex2 flags outside of the normal futex syscalls. Signed-off-by: Jens Axboe --- kernel/futex/futex.h | 2 ++ kernel/futex/syscalls.c | 2 -- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/futex/futex.h b/kernel/futex/futex.h index a06030a1a27b..a173a9d501e1 100644 --- a/kernel/futex/futex.h +++ b/kernel/futex/futex.h @@ -52,6 +52,8 @@ static inline unsigned int futex_to_flags(unsigned int op) return flags; } +#define FUTEX2_VALID_MASK (FUTEX2_SIZE_MASK | FUTEX2_PRIVATE) + /* FUTEX2_ to FLAGS_ */ static inline unsigned int futex2_to_flags(unsigned int flags2) { diff --git a/kernel/futex/syscalls.c b/kernel/futex/syscalls.c index 8200d86d30e1..2b5cafdfdc50 100644 --- a/kernel/futex/syscalls.c +++ b/kernel/futex/syscalls.c @@ -179,8 +179,6 @@ SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val, return do_futex(uaddr, op, val, tp, uaddr2, (unsigned long)utime, val3); } -#define FUTEX2_VALID_MASK (FUTEX2_SIZE_MASK | FUTEX2_PRIVATE) - /** * futex_parse_waitv - Parse a waitv array from userspace * @futexv: Kernel side list of waiters to be filled From patchwork Thu Sep 28 17:25:11 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 13403346 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 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; } From patchwork Thu Sep 28 17:25:12 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 13403347 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 BCB1FE732FF for ; Thu, 28 Sep 2023 17:25:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231899AbjI1RZf (ORCPT ); Thu, 28 Sep 2023 13:25:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40168 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231932AbjI1RZc (ORCPT ); Thu, 28 Sep 2023 13:25:32 -0400 Received: from mail-ej1-x633.google.com (mail-ej1-x633.google.com [IPv6:2a00:1450:4864:20::633]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 85DEBCD5 for ; Thu, 28 Sep 2023 10:25:29 -0700 (PDT) Received: by mail-ej1-x633.google.com with SMTP id a640c23a62f3a-9ae65c0e46fso342068966b.0 for ; Thu, 28 Sep 2023 10:25:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1695921927; x=1696526727; 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=aeITMYfcld3mteb+NSEcBXXoBeyRBDS9X8Wlurs1dfY=; b=lXvTQyEa5u24mMaMoOxgC5v9uj1pFbc/ALXz0mBlCmD1vl709tS7CSZqztxkkEOjR3 tpaPy0SlcULi7K+OUMEYz8rRxlu8By+7nGeh6U7wpPFtm1YroLWkOllJHr9Op4Nj02s9 Uy2MInb/UQGdE5m5cr8HnJCO5tS9OYe3J4FYpaFSvgujWoIfJc6HiWfbP0yxVvi72zFu I3y8AnwA9ifUtYLDFVzlFTe6776N0/DyKSwC9NMwTKDJuy9TpqMqnDn+nAL9uiv4hne5 OYBidcg3yu2ywgO+iCIo14jrvs3OIARlLBF2VwJ9h2rHQpF5+amCjnBoHGDtw3GjrGCM 15VA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695921927; x=1696526727; 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=aeITMYfcld3mteb+NSEcBXXoBeyRBDS9X8Wlurs1dfY=; b=vhH2TbiN48cKoNZ71PH8ifNoH+DpxKWab0bd4TDgvsXVsJ4FnSzK2V7xiR+Y+Lq++D SCIRnRh0Cxn+MMBaWEiOKgwHxGi/z8QKsiYsHt+VjT54DI7hHi9kX86MFx/OHayUtt7a SNI4x/Dn0iv4almGynrAz1+hFIWhLNOwjMR58TxUtn295G+Pvp+4ZOPWQ/9ZnZ7xhl7w J3dKrQOIgonyiEopFOU42Xl3fre/Q8+t5NvQFM7WkGefruUkvATQY86f/8cE6Y2m4WX3 yhJ24anZchH9n4PcNMxms8IA2A86LZa3jkAQ+pXQ/LgqX5s04hrIs6hot5CWr+1XMKI5 lGLA== X-Gm-Message-State: AOJu0YwYqisrF5IFRqFsi4fD5WuJYHwwdi9Vv4/RSjPKsM2Ui9TDMUp5 z9J8f+EyoJ+6nsXULDEj5RNadh38wM8cPhzp/chYatHv X-Google-Smtp-Source: AGHT+IHJ2uM1YZlSZZijhxVhmTA+uIkKbBWR7+AMbCLOEfLXFUo8yZlvHfK1N05feFpjuEOISMg6zA== X-Received: by 2002:a17:906:104e:b0:9b2:bf2d:6b66 with SMTP id j14-20020a170906104e00b009b2bf2d6b66mr1576384ejj.7.1695921927081; Thu, 28 Sep 2023 10:25:27 -0700 (PDT) Received: from localhost.localdomain ([45.147.210.162]) by smtp.gmail.com with ESMTPSA id j17-20020a170906279100b0099329b3ab67sm11151788ejc.71.2023.09.28.10.25.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 28 Sep 2023 10:25:26 -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 3/8] futex: abstract out a __futex_wake_mark() helper Date: Thu, 28 Sep 2023 11:25:12 -0600 Message-Id: <20230928172517.961093-4-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 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Move the unqueue and lock_ptr clear into a helper that futex_wake_mark() calls. Add it to the public functions as well, in preparation for using it outside the core futex code. Suggested-by: Peter Zijlstra Signed-off-by: Jens Axboe --- kernel/futex/futex.h | 1 + kernel/futex/waitwake.c | 33 ++++++++++++++++++++++----------- 2 files changed, 23 insertions(+), 11 deletions(-) diff --git a/kernel/futex/futex.h b/kernel/futex/futex.h index 547f509b2c87..33835b81e0c3 100644 --- a/kernel/futex/futex.h +++ b/kernel/futex/futex.h @@ -219,6 +219,7 @@ extern int futex_wait_setup(u32 __user *uaddr, u32 val, unsigned int flags, struct futex_q *q, struct futex_hash_bucket **hb); extern void futex_wait_queue(struct futex_hash_bucket *hb, struct futex_q *q, struct hrtimer_sleeper *timeout); +extern bool __futex_wake_mark(struct futex_q *q); extern void futex_wake_mark(struct wake_q_head *wake_q, struct futex_q *q); extern int fault_in_user_writeable(u32 __user *uaddr); diff --git a/kernel/futex/waitwake.c b/kernel/futex/waitwake.c index 35c6a637a4bb..6fcf5f723719 100644 --- a/kernel/futex/waitwake.c +++ b/kernel/futex/waitwake.c @@ -106,20 +106,11 @@ * double_lock_hb() and double_unlock_hb(), respectively. */ -/* - * The hash bucket lock must be held when this is called. - * Afterwards, the futex_q must not be accessed. Callers - * must ensure to later call wake_up_q() for the actual - * wakeups to occur. - */ -void futex_wake_mark(struct wake_q_head *wake_q, struct futex_q *q) +bool __futex_wake_mark(struct futex_q *q) { - struct task_struct *p = q->task; - if (WARN(q->pi_state || q->rt_waiter, "refusing to wake PI futex\n")) - return; + return false; - get_task_struct(p); __futex_unqueue(q); /* * The waiting task can free the futex_q as soon as q->lock_ptr = NULL @@ -130,6 +121,26 @@ void futex_wake_mark(struct wake_q_head *wake_q, struct futex_q *q) */ smp_store_release(&q->lock_ptr, NULL); + return true; +} + +/* + * The hash bucket lock must be held when this is called. + * Afterwards, the futex_q must not be accessed. Callers + * must ensure to later call wake_up_q() for the actual + * wakeups to occur. + */ +void futex_wake_mark(struct wake_q_head *wake_q, struct futex_q *q) +{ + struct task_struct *p = q->task; + + get_task_struct(p); + + if (!__futex_wake_mark(q)) { + put_task_struct(p); + return; + } + /* * Queue the task for later wakeup for after we've released * the hb->lock. From patchwork Thu Sep 28 17:25:13 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 13403349 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 E13D6E732FE for ; Thu, 28 Sep 2023 17:25:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231932AbjI1RZi (ORCPT ); Thu, 28 Sep 2023 13:25:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40182 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231958AbjI1RZf (ORCPT ); Thu, 28 Sep 2023 13:25:35 -0400 Received: from mail-ed1-x531.google.com (mail-ed1-x531.google.com [IPv6:2a00:1450:4864:20::531]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 315611AE for ; Thu, 28 Sep 2023 10:25:31 -0700 (PDT) Received: by mail-ed1-x531.google.com with SMTP id 4fb4d7f45d1cf-5221bd8f62eso3186851a12.1 for ; Thu, 28 Sep 2023 10:25:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1695921929; x=1696526729; 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=oUDAZatb2usVAAqKXyRcat3hmGorqbvXZ1XnWxWEmmY=; b=fmSQj+OWf5w+mde6nH8a/7wUIT537p4hgjtMuN73WaS2//FHIGAaZ9ocuwloD3wOyt s/dmCWtj2aUX4zoxed8C5gvM/1WQLcSpPLI8uADpPL3231nbTfD0DqErCqvaqUneOjdp DtVZTd23frKmVerwDrMaQdXDdBzBqVGVZJHNTZhCg94iFWyyu8wP6hZHS5bGIqwh3/W/ 4ovVmiK9q0KzaxNSoliaqd3Bt7oXDTTIYaZ6AD0gsRtQcnp+ICTZIv5C0LZxIVyJGv4W LaZRIP4hfQVgrtu0GZgo8FVd8yKr5npcAQIjxkPzGvEEAYCDpYdNbIh0qVPE5tgL+HIW xUIw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695921929; x=1696526729; 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=oUDAZatb2usVAAqKXyRcat3hmGorqbvXZ1XnWxWEmmY=; b=GHPIH9G1LbYmz1wbdOTwOQ7+UlNlo91wmci9u6dKyirRVGN/V0mz003H346A1OaPcr pM346VOEgIaAiRwwBXjGh2EnHx8kGqZVKN4UVqmodDCyJx7LFKZDNwyKLsGSUrIr/IdV M4OVO8C2inRfnlj9Zx/Lu+OtJJ5P937X3iujqnHzw7uQoR5MNXA6NNOGu9tbYZKOq5X4 I2KG+cB9TgGzY/Iy+ZbIRUydFGbtdGGyht6LbHu9hHumPKkZD1tid1IA+8P4vRIhxMqc PlKZGPaUgacJF4kRmDIDpzZpUr5kFi0oJhltanvzZOoh0xQyjTAIO3jdP1/DMsOWwQ/a yVzA== X-Gm-Message-State: AOJu0YwwFGLHU/dBV3itKjn3pTRNDjrnyRtXPW3HB2gykDK7L8XlDxOj nNl+nRykDhgl7WimqrAEfw4v7zWdH9CY7M2MevJqKJkJ X-Google-Smtp-Source: AGHT+IGlfXV+00wOTKUOatB9Ul15G+8LTPVo6raD1qwE8CrqN3Vn9o+/FNQ0Paf6dtuFMgb0f2guzw== X-Received: by 2002:a17:906:519a:b0:9a1:b4f9:b1db with SMTP id y26-20020a170906519a00b009a1b4f9b1dbmr1877973ejk.1.1695921928860; Thu, 28 Sep 2023 10:25:28 -0700 (PDT) Received: from localhost.localdomain ([45.147.210.162]) by smtp.gmail.com with ESMTPSA id j17-20020a170906279100b0099329b3ab67sm11151788ejc.71.2023.09.28.10.25.27 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 28 Sep 2023 10:25:27 -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 4/8] io_uring: add support for futex wake and wait Date: Thu, 28 Sep 2023 11:25:13 -0600 Message-Id: <20230928172517.961093-5-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 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Add support for FUTEX_WAKE/WAIT primitives. IORING_OP_FUTEX_WAKE is mix of FUTEX_WAKE and FUTEX_WAKE_BITSET, as it does support passing in a bitset. Similary, IORING_OP_FUTEX_WAIT is a mix of FUTEX_WAIT and FUTEX_WAIT_BITSET. For both of them, they are using the futex2 interface. FUTEX_WAKE is straight forward, as those can always be done directly from the io_uring submission without needing async handling. For FUTEX_WAIT, things are a bit more complicated. If the futex isn't ready, then we rely on a callback via futex_queue->wake() when someone wakes up the futex. From that calback, we queue up task_work with the original task, which will post a CQE and wake it, if necessary. Cancelations are supported, both from the application point-of-view, but also to be able to cancel pending waits if the ring exits before all events have occurred. The return value of futex_unqueue() is used to gate who wins the potential race between cancelation and futex wakeups. Whomever gets a 'ret == 1' return from that claims ownership of the io_uring futex request. This is just the barebones wait/wake support. PI or REQUEUE support is not added at this point, unclear if we might look into that later. Likewise, explicit timeouts are not supported either. It is expected that users that need timeouts would do so via the usual io_uring mechanism to do that using linked timeouts. The SQE format is as follows: `addr` Address of futex `fd` futex2(2) FUTEX2_* flags `futex_flags` io_uring specific command flags. None valid now. `addr2` Value of futex `addr3` Mask to wake/wait Signed-off-by: Jens Axboe --- include/linux/io_uring_types.h | 5 + include/uapi/linux/io_uring.h | 3 + io_uring/Makefile | 1 + io_uring/cancel.c | 5 + io_uring/cancel.h | 4 + io_uring/futex.c | 235 +++++++++++++++++++++++++++++++++ io_uring/futex.h | 34 +++++ io_uring/io_uring.c | 7 + io_uring/opdef.c | 23 ++++ 9 files changed, 317 insertions(+) create mode 100644 io_uring/futex.c create mode 100644 io_uring/futex.h diff --git a/include/linux/io_uring_types.h b/include/linux/io_uring_types.h index e178461fa513..990984614fca 100644 --- a/include/linux/io_uring_types.h +++ b/include/linux/io_uring_types.h @@ -321,6 +321,11 @@ struct io_ring_ctx { struct hlist_head waitid_list; +#ifdef CONFIG_FUTEX + struct hlist_head futex_list; + struct io_alloc_cache futex_cache; +#endif + const struct cred *sq_creds; /* cred used for __io_sq_thread() */ struct io_sq_data *sq_data; /* if using sq thread polling */ diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index 425f64eee44e..04f9fba38d4b 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -66,6 +66,7 @@ struct io_uring_sqe { __u32 msg_ring_flags; __u32 uring_cmd_flags; __u32 waitid_flags; + __u32 futex_flags; }; __u64 user_data; /* data to be passed back at completion time */ /* pack this to avoid bogus arm OABI complaints */ @@ -243,6 +244,8 @@ enum io_uring_op { IORING_OP_SENDMSG_ZC, IORING_OP_READ_MULTISHOT, IORING_OP_WAITID, + IORING_OP_FUTEX_WAIT, + IORING_OP_FUTEX_WAKE, /* this goes last, obviously */ IORING_OP_LAST, diff --git a/io_uring/Makefile b/io_uring/Makefile index 7bd64e442567..e5be47e4fc3b 100644 --- a/io_uring/Makefile +++ b/io_uring/Makefile @@ -10,3 +10,4 @@ obj-$(CONFIG_IO_URING) += io_uring.o xattr.o nop.o fs.o splice.o \ cancel.o kbuf.o rsrc.o rw.o opdef.o \ notif.o waitid.o obj-$(CONFIG_IO_WQ) += io-wq.o +obj-$(CONFIG_FUTEX) += futex.o diff --git a/io_uring/cancel.c b/io_uring/cancel.c index eb77a51c5a79..3c19cccb1aec 100644 --- a/io_uring/cancel.c +++ b/io_uring/cancel.c @@ -16,6 +16,7 @@ #include "poll.h" #include "timeout.h" #include "waitid.h" +#include "futex.h" #include "cancel.h" struct io_cancel { @@ -124,6 +125,10 @@ int io_try_cancel(struct io_uring_task *tctx, struct io_cancel_data *cd, if (ret != -ENOENT) return ret; + ret = io_futex_cancel(ctx, cd, issue_flags); + if (ret != -ENOENT) + return ret; + spin_lock(&ctx->completion_lock); if (!(cd->flags & IORING_ASYNC_CANCEL_FD)) ret = io_timeout_cancel(ctx, cd); diff --git a/io_uring/cancel.h b/io_uring/cancel.h index fc98622e6166..c0a8e7c520b6 100644 --- a/io_uring/cancel.h +++ b/io_uring/cancel.h @@ -1,4 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 +#ifndef IORING_CANCEL_H +#define IORING_CANCEL_H #include @@ -22,3 +24,5 @@ void init_hash_table(struct io_hash_table *table, unsigned size); int io_sync_cancel(struct io_ring_ctx *ctx, void __user *arg); bool io_cancel_req_match(struct io_kiocb *req, struct io_cancel_data *cd); + +#endif diff --git a/io_uring/futex.c b/io_uring/futex.c new file mode 100644 index 000000000000..eb4406ac46fb --- /dev/null +++ b/io_uring/futex.c @@ -0,0 +1,235 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include + +#include + +#include "../kernel/futex/futex.h" +#include "io_uring.h" +#include "rsrc.h" +#include "futex.h" + +struct io_futex { + struct file *file; + u32 __user *uaddr; + unsigned long futex_val; + unsigned long futex_mask; + u32 futex_flags; +}; + +struct io_futex_data { + union { + struct futex_q q; + struct io_cache_entry cache; + }; + struct io_kiocb *req; +}; + +void io_futex_cache_init(struct io_ring_ctx *ctx) +{ + io_alloc_cache_init(&ctx->futex_cache, IO_NODE_ALLOC_CACHE_MAX, + sizeof(struct io_futex_data)); +} + +static void io_futex_cache_entry_free(struct io_cache_entry *entry) +{ + kfree(container_of(entry, struct io_futex_data, cache)); +} + +void io_futex_cache_free(struct io_ring_ctx *ctx) +{ + io_alloc_cache_free(&ctx->futex_cache, io_futex_cache_entry_free); +} + +static void io_futex_complete(struct io_kiocb *req, struct io_tw_state *ts) +{ + struct io_futex_data *ifd = req->async_data; + struct io_ring_ctx *ctx = req->ctx; + + io_tw_lock(ctx, ts); + if (!io_alloc_cache_put(&ctx->futex_cache, &ifd->cache)) + kfree(ifd); + req->async_data = NULL; + hlist_del_init(&req->hash_node); + io_req_task_complete(req, ts); +} + +static bool __io_futex_cancel(struct io_ring_ctx *ctx, struct io_kiocb *req) +{ + struct io_futex_data *ifd = req->async_data; + + /* futex wake already done or in progress */ + if (!futex_unqueue(&ifd->q)) + return false; + + hlist_del_init(&req->hash_node); + io_req_set_res(req, -ECANCELED, 0); + req->io_task_work.func = io_futex_complete; + io_req_task_work_add(req); + return true; +} + +int io_futex_cancel(struct io_ring_ctx *ctx, struct io_cancel_data *cd, + unsigned int issue_flags) +{ + struct hlist_node *tmp; + struct io_kiocb *req; + int nr = 0; + + if (cd->flags & (IORING_ASYNC_CANCEL_FD|IORING_ASYNC_CANCEL_FD_FIXED)) + return -ENOENT; + + io_ring_submit_lock(ctx, issue_flags); + hlist_for_each_entry_safe(req, tmp, &ctx->futex_list, hash_node) { + if (req->cqe.user_data != cd->data && + !(cd->flags & IORING_ASYNC_CANCEL_ANY)) + continue; + if (__io_futex_cancel(ctx, req)) + nr++; + if (!(cd->flags & IORING_ASYNC_CANCEL_ALL)) + break; + } + io_ring_submit_unlock(ctx, issue_flags); + + if (nr) + return nr; + + return -ENOENT; +} + +bool io_futex_remove_all(struct io_ring_ctx *ctx, struct task_struct *task, + bool cancel_all) +{ + struct hlist_node *tmp; + struct io_kiocb *req; + bool found = false; + + lockdep_assert_held(&ctx->uring_lock); + + hlist_for_each_entry_safe(req, tmp, &ctx->futex_list, hash_node) { + if (!io_match_task_safe(req, task, cancel_all)) + continue; + __io_futex_cancel(ctx, req); + found = true; + } + + return found; +} + +int io_futex_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) +{ + struct io_futex *iof = io_kiocb_to_cmd(req, struct io_futex); + u32 flags; + + if (unlikely(sqe->len || sqe->futex_flags || sqe->buf_index || + sqe->file_index)) + return -EINVAL; + + iof->uaddr = u64_to_user_ptr(READ_ONCE(sqe->addr)); + iof->futex_val = READ_ONCE(sqe->addr2); + iof->futex_mask = READ_ONCE(sqe->addr3); + flags = READ_ONCE(sqe->fd); + + if (flags & ~FUTEX2_VALID_MASK) + return -EINVAL; + + iof->futex_flags = futex2_to_flags(flags); + if (!futex_flags_valid(iof->futex_flags)) + return -EINVAL; + + if (!futex_validate_input(iof->futex_flags, iof->futex_val) || + !futex_validate_input(iof->futex_flags, iof->futex_mask)) + return -EINVAL; + + return 0; +} + +static void io_futex_wake_fn(struct wake_q_head *wake_q, struct futex_q *q) +{ + struct io_futex_data *ifd = container_of(q, struct io_futex_data, q); + struct io_kiocb *req = ifd->req; + + if (unlikely(!__futex_wake_mark(q))) + return; + + io_req_set_res(req, 0, 0); + req->io_task_work.func = io_futex_complete; + io_req_task_work_add(req); +} + +static struct io_futex_data *io_alloc_ifd(struct io_ring_ctx *ctx) +{ + struct io_cache_entry *entry; + + entry = io_alloc_cache_get(&ctx->futex_cache); + if (entry) + return container_of(entry, struct io_futex_data, cache); + + return kmalloc(sizeof(struct io_futex_data), GFP_NOWAIT); +} + +int io_futex_wait(struct io_kiocb *req, unsigned int issue_flags) +{ + struct io_futex *iof = io_kiocb_to_cmd(req, struct io_futex); + struct io_ring_ctx *ctx = req->ctx; + struct io_futex_data *ifd = NULL; + struct futex_hash_bucket *hb; + int ret; + + if (!iof->futex_mask) { + ret = -EINVAL; + goto done; + } + + io_ring_submit_lock(ctx, issue_flags); + ifd = io_alloc_ifd(ctx); + if (!ifd) { + ret = -ENOMEM; + goto done_unlock; + } + + req->async_data = ifd; + ifd->q = futex_q_init; + ifd->q.bitset = iof->futex_mask; + ifd->q.wake = io_futex_wake_fn; + ifd->req = req; + + ret = futex_wait_setup(iof->uaddr, iof->futex_val, iof->futex_flags, + &ifd->q, &hb); + if (!ret) { + hlist_add_head(&req->hash_node, &ctx->futex_list); + io_ring_submit_unlock(ctx, issue_flags); + + futex_queue(&ifd->q, hb); + return IOU_ISSUE_SKIP_COMPLETE; + } + +done_unlock: + io_ring_submit_unlock(ctx, issue_flags); +done: + if (ret < 0) + req_set_fail(req); + io_req_set_res(req, ret, 0); + kfree(ifd); + return IOU_OK; +} + +int io_futex_wake(struct io_kiocb *req, unsigned int issue_flags) +{ + struct io_futex *iof = io_kiocb_to_cmd(req, struct io_futex); + int ret; + + /* + * Strict flags - ensure that waking 0 futexes yields a 0 result. + * See commit 43adf8449510 ("futex: FLAGS_STRICT") for details. + */ + ret = futex_wake(iof->uaddr, FLAGS_STRICT | iof->futex_flags, + iof->futex_val, iof->futex_mask); + if (ret < 0) + req_set_fail(req); + io_req_set_res(req, ret, 0); + return IOU_OK; +} diff --git a/io_uring/futex.h b/io_uring/futex.h new file mode 100644 index 000000000000..ddc9e0d73c52 --- /dev/null +++ b/io_uring/futex.h @@ -0,0 +1,34 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include "cancel.h" + +int io_futex_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe); +int io_futex_wait(struct io_kiocb *req, unsigned int issue_flags); +int io_futex_wake(struct io_kiocb *req, unsigned int issue_flags); + +#if defined(CONFIG_FUTEX) +int io_futex_cancel(struct io_ring_ctx *ctx, struct io_cancel_data *cd, + unsigned int issue_flags); +bool io_futex_remove_all(struct io_ring_ctx *ctx, struct task_struct *task, + bool cancel_all); +void io_futex_cache_init(struct io_ring_ctx *ctx); +void io_futex_cache_free(struct io_ring_ctx *ctx); +#else +static inline int io_futex_cancel(struct io_ring_ctx *ctx, + struct io_cancel_data *cd, + unsigned int issue_flags) +{ + return 0; +} +static inline bool io_futex_remove_all(struct io_ring_ctx *ctx, + struct task_struct *task, bool cancel_all) +{ + return false; +} +static inline void io_futex_cache_init(struct io_ring_ctx *ctx) +{ +} +static inline void io_futex_cache_free(struct io_ring_ctx *ctx) +{ +} +#endif diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index 08c9ea46bb95..3c1c111d02cb 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -93,6 +93,7 @@ #include "net.h" #include "notif.h" #include "waitid.h" +#include "futex.h" #include "timeout.h" #include "poll.h" @@ -330,6 +331,7 @@ static __cold struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p) sizeof(struct async_poll)); io_alloc_cache_init(&ctx->netmsg_cache, IO_ALLOC_CACHE_MAX, sizeof(struct io_async_msghdr)); + io_futex_cache_init(ctx); init_completion(&ctx->ref_comp); xa_init_flags(&ctx->personalities, XA_FLAGS_ALLOC1); mutex_init(&ctx->uring_lock); @@ -350,6 +352,9 @@ static __cold struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p) ctx->submit_state.free_list.next = NULL; INIT_WQ_LIST(&ctx->locked_free_list); INIT_HLIST_HEAD(&ctx->waitid_list); +#ifdef CONFIG_FUTEX + INIT_HLIST_HEAD(&ctx->futex_list); +#endif INIT_DELAYED_WORK(&ctx->fallback_work, io_fallback_req_func); INIT_WQ_LIST(&ctx->submit_state.compl_reqs); INIT_HLIST_HEAD(&ctx->cancelable_uring_cmd); @@ -2895,6 +2900,7 @@ static __cold void io_ring_ctx_free(struct io_ring_ctx *ctx) io_eventfd_unregister(ctx); io_alloc_cache_free(&ctx->apoll_cache, io_apoll_cache_free); io_alloc_cache_free(&ctx->netmsg_cache, io_netmsg_cache_free); + io_futex_cache_free(ctx); io_destroy_buffers(ctx); mutex_unlock(&ctx->uring_lock); if (ctx->sq_creds) @@ -3338,6 +3344,7 @@ static __cold bool io_uring_try_cancel_requests(struct io_ring_ctx *ctx, mutex_lock(&ctx->uring_lock); ret |= io_poll_remove_all(ctx, task, cancel_all); ret |= io_waitid_remove_all(ctx, task, cancel_all); + ret |= io_futex_remove_all(ctx, task, cancel_all); ret |= io_uring_try_cancel_uring_cmd(ctx, task, cancel_all); mutex_unlock(&ctx->uring_lock); ret |= io_kill_timeouts(ctx, task, cancel_all); diff --git a/io_uring/opdef.c b/io_uring/opdef.c index aadcbf7136b0..31a3a421e94d 100644 --- a/io_uring/opdef.c +++ b/io_uring/opdef.c @@ -34,6 +34,7 @@ #include "cancel.h" #include "rw.h" #include "waitid.h" +#include "futex.h" static int io_no_issue(struct io_kiocb *req, unsigned int issue_flags) { @@ -444,6 +445,22 @@ const struct io_issue_def io_issue_defs[] = { .prep = io_waitid_prep, .issue = io_waitid, }, + [IORING_OP_FUTEX_WAIT] = { +#if defined(CONFIG_FUTEX) + .prep = io_futex_prep, + .issue = io_futex_wait, +#else + .prep = io_eopnotsupp_prep, +#endif + }, + [IORING_OP_FUTEX_WAKE] = { +#if defined(CONFIG_FUTEX) + .prep = io_futex_prep, + .issue = io_futex_wake, +#else + .prep = io_eopnotsupp_prep, +#endif + }, }; const struct io_cold_def io_cold_defs[] = { @@ -670,6 +687,12 @@ const struct io_cold_def io_cold_defs[] = { .name = "WAITID", .async_size = sizeof(struct io_waitid_async), }, + [IORING_OP_FUTEX_WAIT] = { + .name = "FUTEX_WAIT", + }, + [IORING_OP_FUTEX_WAKE] = { + .name = "FUTEX_WAKE", + }, }; const char *io_uring_get_opcode(u8 opcode) From patchwork Thu Sep 28 17:25:14 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 13403348 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 B9364CE7AFC for ; Thu, 28 Sep 2023 17:25:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231986AbjI1RZh (ORCPT ); Thu, 28 Sep 2023 13:25:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40256 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231987AbjI1RZf (ORCPT ); Thu, 28 Sep 2023 13:25:35 -0400 Received: from mail-ej1-x62c.google.com (mail-ej1-x62c.google.com [IPv6:2a00:1450:4864:20::62c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 293ACCEF for ; Thu, 28 Sep 2023 10:25:33 -0700 (PDT) Received: by mail-ej1-x62c.google.com with SMTP id a640c23a62f3a-9b27f99a356so225172866b.0 for ; Thu, 28 Sep 2023 10:25:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1695921930; x=1696526730; 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=v/TGT+v2onwhR3DWI/C2XC90jEj/DLLYrXKmnR2IfXs=; b=chyq2RM7TRkMav4kl6LfB1ZA12RrnS94Jl+ADgBTqgzkD5nViYFBMNoWTo4ueBForF lzmlvsruUlaqklO8yLHrznKdhJMy2EBRos31/CMC++Zh0/i/cHFjNxJaZ03bxRfuU2yy zyxNmJ7HQy1+5/hu0r0Y77IiVN1n7SLdx2VcI8qEMTgRcFlW7P/8UK8IK5HTs5JuQLSE U4yRErpwg5506oVIvt4+v/fWS3TdAytsAD0yrlT3UC04hxiJInYJ1z39DuoI7r+YRebr aU9+DFuNOYzkoE85VRhrWlFdqn4bJGjHyjVbGDTeywWVOShPaNDz/dmHhVKVgOorqeDT +maQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695921930; x=1696526730; 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=v/TGT+v2onwhR3DWI/C2XC90jEj/DLLYrXKmnR2IfXs=; b=N1SWXieT+oHh3pjOluQbyhaAwyWML+raOghNplQXhYpR37HSHXASz4ed3/gZFCAJah SQf+DzyGWOeX3wiM7iHy3JNfmTNYxjcgj/CGCtJHTyW3M1OcOomIBt8De7tTWOFAew69 g+hXzqBt1ejXhyLzOqax9DJtKOU48hH9x5pYwWQ300Ibsph+82L9h1kly4VqAKfzwT+r dAZuofRRWGS0/uojqEbnZVqpbpgRrwKmbukpr47+dFWafEjHdoS7gANqtdv0zuE14B5U gMTZSCjEfP8jNdNtkVkI+H1I0JaOJQvc9ZMjYXIw5rOnZv/PoxdXPqXfYhwUgG9ARlnh WeKg== X-Gm-Message-State: AOJu0YzLQ/KYw+k9Hh9ljz1QKRf85pXqfzwkmOqFQerrLrLwJafpooqG kH3xMcWNKhdl2F1YDgR7qCEEBPYEdpP8FE2mUWLwfqcf X-Google-Smtp-Source: AGHT+IH0euAGYjrCZbgJ8RFIhz/xz08t6fWykn21eNHckLKUHkkweKDGKXgPC/XNOmxmryeAGfBWbA== X-Received: by 2002:a17:906:5185:b0:9ae:50de:1aaf with SMTP id y5-20020a170906518500b009ae50de1aafmr1750879ejk.4.1695921930540; Thu, 28 Sep 2023 10:25:30 -0700 (PDT) Received: from localhost.localdomain ([45.147.210.162]) by smtp.gmail.com with ESMTPSA id j17-20020a170906279100b0099329b3ab67sm11151788ejc.71.2023.09.28.10.25.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 28 Sep 2023 10:25:29 -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 5/8] futex: add wake_data to struct futex_q Date: Thu, 28 Sep 2023 11:25:14 -0600 Message-Id: <20230928172517.961093-6-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 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org With handling multiple futex_q for waitv, we cannot easily go from the futex_q to data related to that request or queue. Add a wake_data argument that belongs to the wake handler assigned. Signed-off-by: Jens Axboe --- kernel/futex/futex.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/futex/futex.h b/kernel/futex/futex.h index 33835b81e0c3..76f6c2e0f539 100644 --- a/kernel/futex/futex.h +++ b/kernel/futex/futex.h @@ -148,6 +148,7 @@ typedef void (futex_wake_fn)(struct wake_q_head *wake_q, struct futex_q *q); * @task: the task waiting on the futex * @lock_ptr: the hash bucket lock * @wake: the wake handler for this queue + * @wake_data: data associated with the wake handler * @key: the key the futex is hashed on * @pi_state: optional priority inheritance state * @rt_waiter: rt_waiter storage for use with requeue_pi @@ -173,6 +174,7 @@ struct futex_q { struct task_struct *task; spinlock_t *lock_ptr; futex_wake_fn *wake; + void *wake_data; union futex_key key; struct futex_pi_state *pi_state; struct rt_mutex_waiter *rt_waiter; From patchwork Thu Sep 28 17:25:15 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 13403350 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 4B790E732FF for ; Thu, 28 Sep 2023 17:25:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232119AbjI1RZo (ORCPT ); Thu, 28 Sep 2023 13:25:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40182 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232007AbjI1RZh (ORCPT ); Thu, 28 Sep 2023 13:25:37 -0400 Received: from mail-ej1-x631.google.com (mail-ej1-x631.google.com [IPv6:2a00:1450:4864:20::631]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9C7F8CC0 for ; Thu, 28 Sep 2023 10:25:34 -0700 (PDT) Received: by mail-ej1-x631.google.com with SMTP id a640c23a62f3a-9ae3d7eb7e0so355435066b.0 for ; Thu, 28 Sep 2023 10:25:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1695921932; x=1696526732; 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=8/OGVEqmKZ+YrEmaYsT23Mong0SvETBYb//Qn3SwQyE=; b=KKqEJg5/0J2pSzaW+ZhrOc7EXQeEHD4+ZX0czpHDEl2Akr6z2EyzfaY3gmvzTugV51 yT9gKDKV3F6sH1nBBqmN/eREyeyBM1B9tShvYz04j6lBTHtM+g/6eTJkUW/bXEoj8aEz xzA48gN1TZq7SPDGhqquMhbvLZaYP/7OzS8P4X8UczVzBXu7Z7tkklaO2LHtzO0dD0qf Ju3CGVwaA3JGw9HELFTRJ0dwxk9g/8YgqYjbJWlKN5kvUnoe9SkGMmx79kzklTs4pYNE uTE+7+osxZlAFdL6/wXQehY+aZOpMbXMUId2duKiF9zd56fgjWyGZxgojSe21EYCTu5X Fi4A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695921932; x=1696526732; 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=8/OGVEqmKZ+YrEmaYsT23Mong0SvETBYb//Qn3SwQyE=; b=KJPonYjfjbLZmfNaUO3QCRMDsU04XsNYdejXTtOHVc5LZXK/bexEYXlW7d9aLfnjHN xs0bTrmOBlzA/yGekBkf4BPhJvXxvsvqN1kW0aTP9onl1Sl+c+mQqKnV6y5q7EPthB6E 1ngFtlawfWZLEf587vk8jwgA/KpCxbpkkeSttSrXtWmpoRViA4ZDXig0ZcgnhNVVBOFw EcClp4xVQ/NhEH7KWEgM0keOUOM4EMd7Vtswe1d+iK9rez0P2LxYJYVhkjoSTMsaeAbY Ya4ctN++cvPFk+NiypnPZ3Bq1OqrEVrOx5VcFVcbUTSD5yNLqG7RayqJ5HMH4c2EHqHp 9p2Q== X-Gm-Message-State: AOJu0YzvnUFbTO1lyhog0CKapTQRuI27eSk8J/Ta1Il1gwwsalbi0BYG n6DRSvXgeIo4Jb9+Z2WHXxIqIWQ3yVua2P+/l3ikDNnz X-Google-Smtp-Source: AGHT+IGbgJvR6igUJNoQ7t3LjqXpJkN7xLgY/4h9TC/rrsy9yWWjLSHI6P59T965jVCWQvsOiOqrEg== X-Received: by 2002:a17:906:5352:b0:9a1:d79a:4190 with SMTP id j18-20020a170906535200b009a1d79a4190mr1460967ejo.2.1695921932053; Thu, 28 Sep 2023 10:25:32 -0700 (PDT) Received: from localhost.localdomain ([45.147.210.162]) by smtp.gmail.com with ESMTPSA id j17-20020a170906279100b0099329b3ab67sm11151788ejc.71.2023.09.28.10.25.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 28 Sep 2023 10:25:31 -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 6/8] futex: make futex_parse_waitv() available as a helper Date: Thu, 28 Sep 2023 11:25:15 -0600 Message-Id: <20230928172517.961093-7-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 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org To make it more generically useful, augment it with allowing the caller to pass in the wake handler and wake data. Convert the futex_waitv() syscall, passing in the default handlers. Signed-off-by: Jens Axboe --- kernel/futex/futex.h | 5 +++++ kernel/futex/syscalls.c | 16 +++++++++++----- 2 files changed, 16 insertions(+), 5 deletions(-) diff --git a/kernel/futex/futex.h b/kernel/futex/futex.h index 76f6c2e0f539..6b6a6b3da103 100644 --- a/kernel/futex/futex.h +++ b/kernel/futex/futex.h @@ -361,6 +361,11 @@ struct futex_vector { struct futex_q q; }; +extern int futex_parse_waitv(struct futex_vector *futexv, + struct futex_waitv __user *uwaitv, + unsigned int nr_futexes, futex_wake_fn *wake, + void *wake_data); + extern int futex_wait_multiple(struct futex_vector *vs, unsigned int count, struct hrtimer_sleeper *to); diff --git a/kernel/futex/syscalls.c b/kernel/futex/syscalls.c index 2b5cafdfdc50..4b6da9116aa6 100644 --- a/kernel/futex/syscalls.c +++ b/kernel/futex/syscalls.c @@ -184,12 +184,15 @@ SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val, * @futexv: Kernel side list of waiters to be filled * @uwaitv: Userspace list to be parsed * @nr_futexes: Length of futexv + * @wake: Wake to call when futex is woken + * @wake_data: Data for the wake handler * * Return: Error code on failure, 0 on success */ -static int futex_parse_waitv(struct futex_vector *futexv, - struct futex_waitv __user *uwaitv, - unsigned int nr_futexes) +int futex_parse_waitv(struct futex_vector *futexv, + struct futex_waitv __user *uwaitv, + unsigned int nr_futexes, futex_wake_fn *wake, + void *wake_data) { struct futex_waitv aux; unsigned int i; @@ -214,6 +217,8 @@ static int futex_parse_waitv(struct futex_vector *futexv, futexv[i].w.val = aux.val; futexv[i].w.uaddr = aux.uaddr; futexv[i].q = futex_q_init; + futexv[i].q.wake = wake; + futexv[i].q.wake_data = wake_data; } return 0; @@ -306,7 +311,8 @@ SYSCALL_DEFINE5(futex_waitv, struct futex_waitv __user *, waiters, goto destroy_timer; } - ret = futex_parse_waitv(futexv, waiters, nr_futexes); + ret = futex_parse_waitv(futexv, waiters, nr_futexes, futex_wake_mark, + NULL); if (!ret) ret = futex_wait_multiple(futexv, nr_futexes, timeout ? &to : NULL); @@ -421,7 +427,7 @@ SYSCALL_DEFINE4(futex_requeue, if (!waiters) return -EINVAL; - ret = futex_parse_waitv(futexes, waiters, 2); + ret = futex_parse_waitv(futexes, waiters, 2, futex_wake_mark, NULL); if (ret) return ret; From patchwork Thu Sep 28 17:25:16 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 13403351 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 403EBE732FE for ; Thu, 28 Sep 2023 17:25:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232158AbjI1RZz (ORCPT ); Thu, 28 Sep 2023 13:25:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40216 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232045AbjI1RZi (ORCPT ); Thu, 28 Sep 2023 13:25:38 -0400 Received: from mail-ej1-x633.google.com (mail-ej1-x633.google.com [IPv6:2a00:1450:4864:20::633]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 83703CC6 for ; Thu, 28 Sep 2023 10:25:35 -0700 (PDT) Received: by mail-ej1-x633.google.com with SMTP id a640c23a62f3a-9b2c5664cb4so29725866b.1 for ; Thu, 28 Sep 2023 10:25:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1695921933; x=1696526733; 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=dMx5R6E0R0h9+pd+QZi7bIoYwQS8EWnvSyRr5gNA3m0=; b=x5KmuZolHfI6zmMIvBkqCBB0NojKGYm/Ej/lsp06NKUeAtEv3Axen0d35ZtfRu2/YL 93crRONQeATlgUnZBlr6Sy52uIdIdTs6B9Fx+NiJrmJ0mibrbtEK9l4YYNY7Il4q+njd OxJQTtMb7L6UIQcU0wSBRJ02NNFh4twwp4Dt8kRDAaJlWoa+hAdykwZBoN2w38iltlAN y8+Lc4o1+QVgA2Oc7vqliXG/OuMbCOheRMrF5glK9DBZexIYUfavQV4Tox6nNgE4HBZZ E7S64ApXCTyIRVbqaU0i6gSdk1KERTeEjpsGWEELiuUfhTwfckiJoYB+jDXGKLkH0Aii nw5A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695921933; x=1696526733; 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=dMx5R6E0R0h9+pd+QZi7bIoYwQS8EWnvSyRr5gNA3m0=; b=YitGEFVMlSzW5XAMBYWhIRwuwUfUW0ZzcBmARFxcD/6HZCLHXKOyqtDTFnilqEkuGR CAg2FCOOU7ON0atyBfBl3j+oamqg2QW8OyBV3DZj+AHD3cx5aeWwSvgvem6+SseeOD0m Au3FM4Ck5eDkw1gC8iY7MmAVBZI/oDgCcGYTM5xQ5V3gFGDtO039oZOV97jCrbfM0JVY XXXVGNexg4VYoTfTte+4mW0IyBgp9z4IhPYFUUe5LUDFlzLtjTcmzdSt8P8HLONdEXWx 3UHdbdAZOxTgGUwYAx0etRH6o8BB+2v0Znph/FcFeHLLaxwy8gbTDzYNPKhwZuTYMKzB nQPA== X-Gm-Message-State: AOJu0Ywkkuxvs5X2Ng30UkddgDDVB86/PiPABYpXwevEZOgEWQ8/+Tfk TIoLjMD0HaUI/xYtS8kVOw6UNuGImuZRS+T8Q4ZlYeaU X-Google-Smtp-Source: AGHT+IHa3Y9Bw3hn4IrDS6VS6xTff2Gj6P6+DF3gCheqbj1zXStjS6Sn/03mJnzS1w+wQW5J4kl0TQ== X-Received: by 2002:a17:906:25d:b0:9b2:bf2d:6b65 with SMTP id 29-20020a170906025d00b009b2bf2d6b65mr2106678ejl.4.1695921933527; Thu, 28 Sep 2023 10:25:33 -0700 (PDT) Received: from localhost.localdomain ([45.147.210.162]) by smtp.gmail.com with ESMTPSA id j17-20020a170906279100b0099329b3ab67sm11151788ejc.71.2023.09.28.10.25.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 28 Sep 2023 10:25:32 -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 7/8] futex: make the vectored futex operations available Date: Thu, 28 Sep 2023 11:25:16 -0600 Message-Id: <20230928172517.961093-8-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 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Rename unqueue_multiple() as futex_unqueue_multiple(), and make both that and futex_wait_multiple_setup() available for external users. This is in preparation for wiring up vectored waits in io_uring. Signed-off-by: Jens Axboe --- kernel/futex/futex.h | 5 +++++ kernel/futex/waitwake.c | 10 +++++----- 2 files changed, 10 insertions(+), 5 deletions(-) diff --git a/kernel/futex/futex.h b/kernel/futex/futex.h index 6b6a6b3da103..8b195d06f4e8 100644 --- a/kernel/futex/futex.h +++ b/kernel/futex/futex.h @@ -366,6 +366,11 @@ extern int futex_parse_waitv(struct futex_vector *futexv, unsigned int nr_futexes, futex_wake_fn *wake, void *wake_data); +extern int futex_wait_multiple_setup(struct futex_vector *vs, int count, + int *woken); + +extern int futex_unqueue_multiple(struct futex_vector *v, int count); + extern int futex_wait_multiple(struct futex_vector *vs, unsigned int count, struct hrtimer_sleeper *to); diff --git a/kernel/futex/waitwake.c b/kernel/futex/waitwake.c index 6fcf5f723719..61b112897a84 100644 --- a/kernel/futex/waitwake.c +++ b/kernel/futex/waitwake.c @@ -372,7 +372,7 @@ void futex_wait_queue(struct futex_hash_bucket *hb, struct futex_q *q, } /** - * unqueue_multiple - Remove various futexes from their hash bucket + * futex_unqueue_multiple - Remove various futexes from their hash bucket * @v: The list of futexes to unqueue * @count: Number of futexes in the list * @@ -382,7 +382,7 @@ void futex_wait_queue(struct futex_hash_bucket *hb, struct futex_q *q, * - >=0 - Index of the last futex that was awoken; * - -1 - No futex was awoken */ -static int unqueue_multiple(struct futex_vector *v, int count) +int futex_unqueue_multiple(struct futex_vector *v, int count) { int ret = -1, i; @@ -410,7 +410,7 @@ static int unqueue_multiple(struct futex_vector *v, int count) * - 0 - Success * - <0 - -EFAULT, -EWOULDBLOCK or -EINVAL */ -static int futex_wait_multiple_setup(struct futex_vector *vs, int count, int *woken) +int futex_wait_multiple_setup(struct futex_vector *vs, int count, int *woken) { struct futex_hash_bucket *hb; bool retry = false; @@ -472,7 +472,7 @@ static int futex_wait_multiple_setup(struct futex_vector *vs, int count, int *wo * was woken, we don't return error and return this index to * userspace */ - *woken = unqueue_multiple(vs, i); + *woken = futex_unqueue_multiple(vs, i); if (*woken >= 0) return 1; @@ -557,7 +557,7 @@ int futex_wait_multiple(struct futex_vector *vs, unsigned int count, __set_current_state(TASK_RUNNING); - ret = unqueue_multiple(vs, count); + ret = futex_unqueue_multiple(vs, count); if (ret >= 0) return ret; From patchwork Thu Sep 28 17:25:17 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 13403352 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 44142E732FF for ; Thu, 28 Sep 2023 17:25:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231652AbjI1RZ5 (ORCPT ); Thu, 28 Sep 2023 13:25:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55702 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232142AbjI1RZv (ORCPT ); Thu, 28 Sep 2023 13:25:51 -0400 Received: from mail-ej1-x62d.google.com (mail-ej1-x62d.google.com [IPv6:2a00:1450:4864:20::62d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E1BA81A3 for ; Thu, 28 Sep 2023 10:25:36 -0700 (PDT) Received: by mail-ej1-x62d.google.com with SMTP id a640c23a62f3a-9a1bcc540c0so349166266b.1 for ; Thu, 28 Sep 2023 10:25:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1695921935; x=1696526735; 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=n9pNfSmgoO/6zgbmdJj7yqQWCPYQ2n2ZMjs03U8i3Ac=; b=aulyJR9J4odx8b7LMUrcvNdAGld9cmuhhxUeWa0NdaYxwaFNQPHoj0Uv8HMnPVei1l z6rMfGE2on9yomZTtnf54AormX4tLIaJg4BEUHgDhMwmxzb1aVZkiIpryXJ1p7u3GpI+ rh7EZ27rVZYnXhrBAeyh6oX1lvZAaWFNNV3bliSPz3d/G3iqaJfdbPk+nR2RralZgAmF KakWzMz1Nd8XEQHkKkPvTMRPkxuGY4rwQ2zn+sgcy7lIsKv2ek/HU1pTIFOSwtvj87zF f8jkMTOdKwKLkI28ghYlgsCly3af4wvxTPWHnoOvLjvPpcAKY8W+17loCejNbA1QnVTs MB/w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695921935; x=1696526735; 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=n9pNfSmgoO/6zgbmdJj7yqQWCPYQ2n2ZMjs03U8i3Ac=; b=QrU0TgotrrJGqCv5t2CM8+fbVdgsu6YgZbRgazzqDPeuHatQy12jKJIinjSZTv24I0 R9/aY6jJL9wVFIQ49BNuectsfav7Gyoewn8VBpJxnGy9aegDMWF0vpqtake5itU9XawV dQr74quh7cOPeS3p9Ipo6BSeQF+s7/syeAW2Nq75ZrucLDDAdF8j+Qn9FioVxffKlDhu LaHQDwl5C2z/oms8iiz6+sv8WzqT+2F8XocCXO/JoPYT4IWmdu4Lyn4LrhBn+Plctw/N eicBnX0HC5ef35TTmi/36QmDuFMYaFEKEUfXEvUbhNL2N7R0GdPq1XYRTXem+gIs6eSc YkGg== X-Gm-Message-State: AOJu0YyL1cZepSy7wP6R0NKs2xhx7h2/EsJQaLL61rWzLm9uw8xdIuE0 rB8vmP+hJYrUqrul6psYRSuTKoML/SLb91Hhp1MFdLxI X-Google-Smtp-Source: AGHT+IFUP9vS47vrviSl7sjXnjGqkAKP4WwY5YGZoh2TzhNdlBsa6XwNha4d5tI2s/BT6T1TLuu5qQ== X-Received: by 2002:a17:906:9f05:b0:9b2:b532:d8d7 with SMTP id fy5-20020a1709069f0500b009b2b532d8d7mr1833220ejc.5.1695921934818; Thu, 28 Sep 2023 10:25:34 -0700 (PDT) Received: from localhost.localdomain ([45.147.210.162]) by smtp.gmail.com with ESMTPSA id j17-20020a170906279100b0099329b3ab67sm11151788ejc.71.2023.09.28.10.25.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 28 Sep 2023 10:25:34 -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 8/8] io_uring: add support for vectored futex waits Date: Thu, 28 Sep 2023 11:25:17 -0600 Message-Id: <20230928172517.961093-9-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 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org This adds support for IORING_OP_FUTEX_WAITV, which allows registering a notification for a number of futexes at once. If one of the futexes are woken, then the request will complete with the index of the futex that got woken as the result. This is identical to what the normal vectored futex waitv operation does. Use like IORING_OP_FUTEX_WAIT, except sqe->addr must now contain a pointer to a struct futex_waitv array, and sqe->off must now contain the number of elements in that array. As flags are passed in the futex_vector array, and likewise for the value and futex address(es), sqe->addr2 and sqe->addr3 are also reserved for IORING_OP_FUTEX_WAITV. For cancelations, FUTEX_WAITV does not rely on the futex_unqueue() return value as we're dealing with multiple futexes. Instead, a separate per io_uring request atomic is used to claim ownership of the request. Waiting on N futexes could be done with IORING_OP_FUTEX_WAIT as well, but that punts a lot of the work to the application: 1) Application would need to submit N IORING_OP_FUTEX_WAIT requests, rather than just a single IORING_OP_FUTEX_WAITV. 2) When one futex is woken, application would need to cancel the remaining N-1 requests that didn't trigger. While this is of course doable, having a single vectored futex wait makes for much simpler application code. Signed-off-by: Jens Axboe --- include/uapi/linux/io_uring.h | 1 + io_uring/futex.c | 169 ++++++++++++++++++++++++++++++++-- io_uring/futex.h | 2 + io_uring/opdef.c | 11 +++ 4 files changed, 174 insertions(+), 9 deletions(-) diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index 04f9fba38d4b..92be89a871fc 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -246,6 +246,7 @@ enum io_uring_op { IORING_OP_WAITID, IORING_OP_FUTEX_WAIT, IORING_OP_FUTEX_WAKE, + IORING_OP_FUTEX_WAITV, /* this goes last, obviously */ IORING_OP_LAST, diff --git a/io_uring/futex.c b/io_uring/futex.c index eb4406ac46fb..3c3575303c3d 100644 --- a/io_uring/futex.c +++ b/io_uring/futex.c @@ -14,10 +14,16 @@ struct io_futex { struct file *file; - u32 __user *uaddr; + union { + u32 __user *uaddr; + struct futex_waitv __user *uwaitv; + }; unsigned long futex_val; unsigned long futex_mask; + unsigned long futexv_owned; u32 futex_flags; + unsigned int futex_nr; + bool futexv_unqueued; }; struct io_futex_data { @@ -44,6 +50,13 @@ void io_futex_cache_free(struct io_ring_ctx *ctx) io_alloc_cache_free(&ctx->futex_cache, io_futex_cache_entry_free); } +static void __io_futex_complete(struct io_kiocb *req, struct io_tw_state *ts) +{ + req->async_data = NULL; + hlist_del_init(&req->hash_node); + io_req_task_complete(req, ts); +} + static void io_futex_complete(struct io_kiocb *req, struct io_tw_state *ts) { struct io_futex_data *ifd = req->async_data; @@ -52,22 +65,56 @@ static void io_futex_complete(struct io_kiocb *req, struct io_tw_state *ts) io_tw_lock(ctx, ts); if (!io_alloc_cache_put(&ctx->futex_cache, &ifd->cache)) kfree(ifd); - req->async_data = NULL; - hlist_del_init(&req->hash_node); - io_req_task_complete(req, ts); + __io_futex_complete(req, ts); } -static bool __io_futex_cancel(struct io_ring_ctx *ctx, struct io_kiocb *req) +static void io_futexv_complete(struct io_kiocb *req, struct io_tw_state *ts) { - struct io_futex_data *ifd = req->async_data; + struct io_futex *iof = io_kiocb_to_cmd(req, struct io_futex); + struct futex_vector *futexv = req->async_data; - /* futex wake already done or in progress */ - if (!futex_unqueue(&ifd->q)) + io_tw_lock(req->ctx, ts); + + if (!iof->futexv_unqueued) { + int res; + + res = futex_unqueue_multiple(futexv, iof->futex_nr); + if (res != -1) + io_req_set_res(req, res, 0); + } + + kfree(req->async_data); + req->flags &= ~REQ_F_ASYNC_DATA; + __io_futex_complete(req, ts); +} + +static bool io_futexv_claim(struct io_futex *iof) +{ + if (test_bit(0, &iof->futexv_owned) || + test_and_set_bit_lock(0, &iof->futexv_owned)) return false; + return true; +} + +static bool __io_futex_cancel(struct io_ring_ctx *ctx, struct io_kiocb *req) +{ + /* futex wake already done or in progress */ + if (req->opcode == IORING_OP_FUTEX_WAIT) { + struct io_futex_data *ifd = req->async_data; + + if (!futex_unqueue(&ifd->q)) + return false; + req->io_task_work.func = io_futex_complete; + } else { + struct io_futex *iof = io_kiocb_to_cmd(req, struct io_futex); + + if (!io_futexv_claim(iof)) + return false; + req->io_task_work.func = io_futexv_complete; + } hlist_del_init(&req->hash_node); io_req_set_res(req, -ECANCELED, 0); - req->io_task_work.func = io_futex_complete; io_req_task_work_add(req); return true; } @@ -147,6 +194,55 @@ int io_futex_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) return 0; } +static void io_futex_wakev_fn(struct wake_q_head *wake_q, struct futex_q *q) +{ + struct io_kiocb *req = q->wake_data; + struct io_futex *iof = io_kiocb_to_cmd(req, struct io_futex); + + if (!io_futexv_claim(iof)) + return; + if (unlikely(!__futex_wake_mark(q))) + return; + + io_req_set_res(req, 0, 0); + req->io_task_work.func = io_futexv_complete; + io_req_task_work_add(req); +} + +int io_futexv_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) +{ + struct io_futex *iof = io_kiocb_to_cmd(req, struct io_futex); + struct futex_vector *futexv; + int ret; + + /* No flags or mask supported for waitv */ + if (unlikely(sqe->fd || sqe->buf_index || sqe->file_index || + sqe->addr2 || sqe->futex_flags || sqe->addr3)) + return -EINVAL; + + iof->uaddr = u64_to_user_ptr(READ_ONCE(sqe->addr)); + iof->futex_nr = READ_ONCE(sqe->len); + if (!iof->futex_nr || iof->futex_nr > FUTEX_WAITV_MAX) + return -EINVAL; + + futexv = kcalloc(iof->futex_nr, sizeof(*futexv), GFP_KERNEL); + if (!futexv) + return -ENOMEM; + + ret = futex_parse_waitv(futexv, iof->uwaitv, iof->futex_nr, + io_futex_wakev_fn, req); + if (ret) { + kfree(futexv); + return ret; + } + + iof->futexv_owned = 0; + iof->futexv_unqueued = 0; + req->flags |= REQ_F_ASYNC_DATA; + req->async_data = futexv; + return 0; +} + static void io_futex_wake_fn(struct wake_q_head *wake_q, struct futex_q *q) { struct io_futex_data *ifd = container_of(q, struct io_futex_data, q); @@ -171,6 +267,61 @@ static struct io_futex_data *io_alloc_ifd(struct io_ring_ctx *ctx) return kmalloc(sizeof(struct io_futex_data), GFP_NOWAIT); } +int io_futexv_wait(struct io_kiocb *req, unsigned int issue_flags) +{ + struct io_futex *iof = io_kiocb_to_cmd(req, struct io_futex); + struct futex_vector *futexv = req->async_data; + struct io_ring_ctx *ctx = req->ctx; + int ret, woken = -1; + + io_ring_submit_lock(ctx, issue_flags); + + ret = futex_wait_multiple_setup(futexv, iof->futex_nr, &woken); + + /* + * Error case, ret is < 0. Mark the request as failed. + */ + if (unlikely(ret < 0)) { + io_ring_submit_unlock(ctx, issue_flags); + req_set_fail(req); + io_req_set_res(req, ret, 0); + kfree(futexv); + req->async_data = NULL; + req->flags &= ~REQ_F_ASYNC_DATA; + return IOU_OK; + } + + /* + * 0 return means that we successfully setup the waiters, and that + * nobody triggered a wakeup while we were doing so. If the wakeup + * happened post setup, the task_work will be run post this issue and + * under the submission lock. 1 means We got woken while setting up, + * let that side do the completion. Note that + * futex_wait_multiple_setup() will have unqueued all the futexes in + * this case. Mark us as having done that already, since this is + * different from normal wakeup. + */ + if (!ret) { + /* + * If futex_wait_multiple_setup() returns 0 for a + * successful setup, then the task state will not be + * runnable. This is fine for the sync syscall, as + * it'll be blocking unless we already got one of the + * futexes woken, but it obviously won't work for an + * async invocation. Mark us runnable again. + */ + __set_current_state(TASK_RUNNING); + hlist_add_head(&req->hash_node, &ctx->futex_list); + } else { + iof->futexv_unqueued = 1; + if (woken != -1) + io_req_set_res(req, woken, 0); + } + + io_ring_submit_unlock(ctx, issue_flags); + return IOU_ISSUE_SKIP_COMPLETE; +} + int io_futex_wait(struct io_kiocb *req, unsigned int issue_flags) { struct io_futex *iof = io_kiocb_to_cmd(req, struct io_futex); diff --git a/io_uring/futex.h b/io_uring/futex.h index ddc9e0d73c52..0847e9e8a127 100644 --- a/io_uring/futex.h +++ b/io_uring/futex.h @@ -3,7 +3,9 @@ #include "cancel.h" int io_futex_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe); +int io_futexv_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe); int io_futex_wait(struct io_kiocb *req, unsigned int issue_flags); +int io_futexv_wait(struct io_kiocb *req, unsigned int issue_flags); int io_futex_wake(struct io_kiocb *req, unsigned int issue_flags); #if defined(CONFIG_FUTEX) diff --git a/io_uring/opdef.c b/io_uring/opdef.c index 31a3a421e94d..25a3515a177c 100644 --- a/io_uring/opdef.c +++ b/io_uring/opdef.c @@ -459,6 +459,14 @@ const struct io_issue_def io_issue_defs[] = { .issue = io_futex_wake, #else .prep = io_eopnotsupp_prep, +#endif + }, + [IORING_OP_FUTEX_WAITV] = { +#if defined(CONFIG_FUTEX) + .prep = io_futexv_prep, + .issue = io_futexv_wait, +#else + .prep = io_eopnotsupp_prep, #endif }, }; @@ -693,6 +701,9 @@ const struct io_cold_def io_cold_defs[] = { [IORING_OP_FUTEX_WAKE] = { .name = "FUTEX_WAKE", }, + [IORING_OP_FUTEX_WAITV] = { + .name = "FUTEX_WAITV", + }, }; const char *io_uring_get_opcode(u8 opcode)