From patchwork Thu Sep 21 18:29:01 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 13394433 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 BF5FEE7D0A7 for ; Thu, 21 Sep 2023 19:53:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229962AbjIUTxY (ORCPT ); Thu, 21 Sep 2023 15:53:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45594 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230323AbjIUTxH (ORCPT ); Thu, 21 Sep 2023 15:53:07 -0400 Received: from mail-io1-xd2e.google.com (mail-io1-xd2e.google.com [IPv6:2607:f8b0:4864:20::d2e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 07214D7DB0 for ; Thu, 21 Sep 2023 11:29:16 -0700 (PDT) Received: by mail-io1-xd2e.google.com with SMTP id ca18e2360f4ac-760dff4b701so17914539f.0 for ; Thu, 21 Sep 2023 11:29:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1695320955; x=1695925755; 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=3PZrgb1nRUzH+q34WXjmHZtiDYbauRH6ZureE/sLaQKEcv8oVAXwj1eWrHEhRvjm1h 9d+JC16iwfuIoilg/Yr118CqhDgJ3UPADorZJFI2Wgc4ggtUzRxFBvfaLh4pFBAPz7DD y6cOLDNAtnFpbpjtuArdh5ZZwukRny0qkl+xlZODxqowZHqYb1FvYNzKDgYfQ/NrqVUM y7x7RJ9d1UM62rcDjPYri4+4azKb3znmMxJDNlLMe6pkHe0EKksZRODiCJiBEwRCZKfx /X9rNKLAFdx1sqZOhUnmlJVBCkleJzXdSmOHiKHacWG/Z2yXt2gSJjz3XE318ySbMDxD jxtg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695320955; x=1695925755; 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=U6YVgsaZsvuKHH5qIYHS5MenMeGu2FVbak3hgBZEXJB6GhJt/eTeFFq60UWzSuzyD2 u7PXCOH9Gk2a0XhfGyi4F6H3x2CsZpQX1fFHDBs2Zx0KoK7rEqUoBkVipvX6AtYGDQaD PCjF0aZS1dG05Z14+Sb+HIqoGIBk4roEuO9rrFJIjEOL5A3yKAH/P7CXWB297ID0qsc6 JxhsjArIRrY1+YlEy9IsauatS4sUfJHyaD1Jm/RuxV/GnKxLSwqOQzcMy9gdq6kc1gHr IQ58yFZy/0uyX7IM2EyAYiitmye+aBn1kikymIG6k6QdWA9g7qpohdU4RdTO5nVC5yhE o3Hg== X-Gm-Message-State: AOJu0YyxAnU1dT18ERmWM0h5qWMryvJGqhe91SFKvsQRXK10cqFGKcyf g5X0DahwXnMXjwCbjaa1okMQeSgRToQudYoVrgu51g== X-Google-Smtp-Source: AGHT+IGHwyaEomy/zYb0m5iH1+xev/kGc2neOyBfwfCE6efVjwCyU3nluV/6eZCqeHaJ1+RHGRHC6A== X-Received: by 2002:a05:6602:2c0a:b0:790:958e:a667 with SMTP id w10-20020a0566022c0a00b00790958ea667mr8177590iov.2.1695320954925; Thu, 21 Sep 2023 11:29:14 -0700 (PDT) Received: from localhost.localdomain ([96.43.243.2]) by smtp.gmail.com with ESMTPSA id o25-20020a02c6b9000000b0042b227eb1ddsm500441jan.55.2023.09.21.11.29.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 Sep 2023 11:29:13 -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, 21 Sep 2023 12:29:01 -0600 Message-Id: <20230921182908.160080-2-axboe@kernel.dk> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230921182908.160080-1-axboe@kernel.dk> References: <20230921182908.160080-1-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 21 18:29:02 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 13394286 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 D45C3E7D0AC for ; Thu, 21 Sep 2023 18:37:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229925AbjIUShs (ORCPT ); Thu, 21 Sep 2023 14:37:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35350 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229799AbjIUShR (ORCPT ); Thu, 21 Sep 2023 14:37:17 -0400 Received: from mail-il1-x131.google.com (mail-il1-x131.google.com [IPv6:2607:f8b0:4864:20::131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4B603D7DB6 for ; Thu, 21 Sep 2023 11:29:17 -0700 (PDT) Received: by mail-il1-x131.google.com with SMTP id e9e14a558f8ab-34e1757fe8fso1016745ab.0 for ; Thu, 21 Sep 2023 11:29:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1695320956; x=1695925756; 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=pbeT1sbpkNh70vmMi3c2YLE6X/cRjVCPHP3VLnlyOgV6DtqthEfXH5xxiCUWNyq/aO Uev+MjFXqt/oSR+daovj2eWyBPsl3J/V3e7S4RjbmQ0mEYo65rVU1Faks5HvQjJ8yxm2 wjApNCrR206ws+T0WdYaGkPQoFRu59KCbABM+wp9dRYj2m6dPNeOsW/kFJyYjtoHE6Td 8chLc/WsroHdM7R3Nwb+37BgSrs1iijFll/osPXPuPQQsxBMY3bTCFNqjpuxqmLndUGW JgH/SYxLnTbYMyePJU1yjHhAmuhxwZSJiPznc9pjH3UKrnHOZDgsnnMXfPgxTLf2a+wH +jjQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695320956; x=1695925756; 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=nPodgUEzibZNLu+UYcvMYg4Va3O2yf3UgcuQEyLw1cMlNRW/rwtIgtUtd62KY453Bf yUuo41uoN+tAq6PDn0XF47QS+qk8cyffu2WmRRtzpLgDZJAh44pcjq9OO/wOcidUusSa 4qhZrrHArf1ZMR572DvmcaqgwOtKuwyoOQzctpp3m/xZ8PEDZz5a1Yv50H3Of4q4jZiA pNVEi+sQ/pT+R9xwz5lQkURQH8Lg79UMR9UBUZFxI6oFrlQvdu3IjRDdywzoNiWjBQz0 F7Y4309hldRiaRQkOBTpUXK0IIuwOyV67AX65M05/I4KCvdrt/MeaHHYNvknP83RKopr chgQ== X-Gm-Message-State: AOJu0YzIlbeSkpmBCXnSbdzARzL8eE0JNjwQxPrKe+rkjuRsu8KcEAv7 ZYAxDEtxwH996VRWfukdN/ipyRazXpER7ysa3IyJuA== X-Google-Smtp-Source: AGHT+IGqEzddFnDbKkDtYGA8ktTswxfUZvEcKcJvZukcbX41+WzSSJZjWINRWy9kHKvClMEuc2TsUQ== X-Received: by 2002:a05:6602:4996:b0:79a:c487:2711 with SMTP id eg22-20020a056602499600b0079ac4872711mr7316666iob.0.1695320956283; Thu, 21 Sep 2023 11:29:16 -0700 (PDT) Received: from localhost.localdomain ([96.43.243.2]) by smtp.gmail.com with ESMTPSA id o25-20020a02c6b9000000b0042b227eb1ddsm500441jan.55.2023.09.21.11.29.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 Sep 2023 11:29:15 -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, 21 Sep 2023 12:29:02 -0600 Message-Id: <20230921182908.160080-3-axboe@kernel.dk> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230921182908.160080-1-axboe@kernel.dk> References: <20230921182908.160080-1-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 21 18:29:03 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 13394282 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 BD22AE7D0A6 for ; Thu, 21 Sep 2023 18:37:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230347AbjIUSho (ORCPT ); Thu, 21 Sep 2023 14:37:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35374 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230300AbjIUShR (ORCPT ); Thu, 21 Sep 2023 14:37:17 -0400 Received: from mail-io1-xd2b.google.com (mail-io1-xd2b.google.com [IPv6:2607:f8b0:4864:20::d2b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CD9EED7DBA for ; Thu, 21 Sep 2023 11:29:18 -0700 (PDT) Received: by mail-io1-xd2b.google.com with SMTP id ca18e2360f4ac-79f96830e4dso3975739f.1 for ; Thu, 21 Sep 2023 11:29:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1695320957; x=1695925757; 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=elkX0bbQnyNGl1I50jhGbi+pWcQeuY5xLC5VLpCo+FVlOp7UwN6P0Qjig8a5k6gTkQ IL7gyU0LgEPpo9Y/PpIaiUVN0MVHLzLecVmUCsHkN14IwxkjxIkhNo9w2VQxBKO2Gpyr T3n2Z7dN+Z75R5u4IwI8PyaftN/9UYXl9GqRtbYkA4PM7NrFR1UmBTFreO0O11jsr1a4 DbXsv1worfom++ih99/XxocYLChcdRN0DHTxZPIdcbChypfX1OaaNmOSAeXQr2AkEGZZ H8ULrGx+Y3Ie51DabPn9XxVnN6c6uFlFfjOXjZgyG9q3PPDHxGudBcFECoeA6MCZe4Eq jFCg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695320957; x=1695925757; 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=ag37ZVE7GxFR1PqwOZ5zrzE5YLJrQzE0WMp08Zlcy1QsW98y1K6bfFy7NAhK2yVD8b xTPAs2rRQDaaWLUAdMsUkoSikISWtWHQPG/owWdW7oMzIjz9cfk8+4OJCzHXJY7EJahy kUXxNNn3gI1j0VLuQqC6KK6zVVMT8Qg5CUnb1F8QSXEDNbEWaYDLje75Os+mahnaDYy8 KWpSD7fPt0d+rgW+UqOEwZ7UeN+Xl/oKQKNnG6HF4jm98Gq3ulJIPcfOyvIXmrReYprp pFb/zBO8Nux3KK4/It37vSU7AQFz7gGL3bpJw85QhK4Dt+A1CvrgCwhGnweQ3UAcfEOd MwuQ== X-Gm-Message-State: AOJu0YxPtnAcsW40OdP5NvpenFhFD9L+XERvgf3BiZf3+VWvYTmjoxnN nsSMtbUjEEWN2BQdJvEzy2fiQeUIXfLpptuSJ8uWZg== X-Google-Smtp-Source: AGHT+IEMeR7eiw0nzdlaXpVdshFLf4QAnYLaYjf6wZVS+llAK8oxoAXqFB8JQnoxkaPkNldByScrSw== X-Received: by 2002:a92:d903:0:b0:350:f353:4017 with SMTP id s3-20020a92d903000000b00350f3534017mr6601502iln.0.1695320957710; Thu, 21 Sep 2023 11:29:17 -0700 (PDT) Received: from localhost.localdomain ([96.43.243.2]) by smtp.gmail.com with ESMTPSA id o25-20020a02c6b9000000b0042b227eb1ddsm500441jan.55.2023.09.21.11.29.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 Sep 2023 11:29:16 -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, 21 Sep 2023 12:29:03 -0600 Message-Id: <20230921182908.160080-4-axboe@kernel.dk> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230921182908.160080-1-axboe@kernel.dk> References: <20230921182908.160080-1-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 21 18:29:04 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 13394280 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 8E284E7D0A2 for ; Thu, 21 Sep 2023 18:37:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229685AbjIUShn (ORCPT ); Thu, 21 Sep 2023 14:37:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34960 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229696AbjIUShT (ORCPT ); Thu, 21 Sep 2023 14:37:19 -0400 Received: from mail-io1-xd30.google.com (mail-io1-xd30.google.com [IPv6:2607:f8b0:4864:20::d30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5AF72D7DBE for ; Thu, 21 Sep 2023 11:29:20 -0700 (PDT) Received: by mail-io1-xd30.google.com with SMTP id ca18e2360f4ac-760dff4b701so17916439f.0 for ; Thu, 21 Sep 2023 11:29:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1695320959; x=1695925759; 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=7k8ejLYif2IyrgBYm50aE+8b9yDEF7uyTbKhg5k4iOU=; b=pwijKD9hdirFOef0c5Z21XQag4QOl6ce9O1OwytB7awhWDi0kaceNEgjsuTEXuOskZ JEa5aOylzELWipInx3NTX4rur5OSJ4m5QExMAGf8ZNzpwlOnm4+2HM0KFu5FKWRVQ4gq 8yCmWhzAGd341ICgyelAUNYIImVZxO/f6P8dLSboiOj6cZbVlR92GrnYYGyGjjKPgx2S 5WNvKCvk7vP0S7FYp3WTZDIrD2eHcPzZ12WThAaUZZT6nubaL5VfSbhBYLD9b9DDJ0mC DujFrkpUBpoStHXRlPBnW8sgmoa7M5WURKH9Lz+ZodvAAM6AsS0Mn3UGpitOqklXv9Uo 9gzg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695320959; x=1695925759; 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=7k8ejLYif2IyrgBYm50aE+8b9yDEF7uyTbKhg5k4iOU=; b=lo4OtPpXrB3ls/V/C/UoLn4c8IgNAO1gtpUA3j1Dt3HNq9XA8pQVKjbey0W95b0ExL SpvqeIId4bLy33Y+teISN+1c6b38lJU8ARyk8A4kGdo3xuclJ0fRklTKPO4w9PEuTzLj /6791tpcEsI/rxskwZ/5igZwPorM2NdoEAj7r5b7EtZAD5wb5DUnzqE57svwrAkmxj0f /+/va+PZg5njzR7KHR+GVoBAbGc8+586a40Uezo4puZcl+9sJvFs+jSg2FHXQrH6kui+ SOTI4SaLsGde7A7Uix2JHpjrA/65E+geUed5KDdgqTHjyH4yio7ZdDx1YICKfrZs+Eub BB6g== X-Gm-Message-State: AOJu0YyvWEDWMs/E7XclCttorALx3RUu1ak1wJ+mf1q8bGFWqdlSncyP edUkDNqOf3Rs7coVVCkJtIyX2I0l70A3AYyeZRg6jw== X-Google-Smtp-Source: AGHT+IGwUCr/QVPU6WQYJLu4Cb8FstNEwPtw4OBtz9SsmN7t4qsLnD4PGtTMSjdDfe/ZXuq2d1yu6A== X-Received: by 2002:a05:6602:2e15:b0:792:6dd8:a65f with SMTP id o21-20020a0566022e1500b007926dd8a65fmr8609274iow.0.1695320958988; Thu, 21 Sep 2023 11:29:18 -0700 (PDT) Received: from localhost.localdomain ([96.43.243.2]) by smtp.gmail.com with ESMTPSA id o25-20020a02c6b9000000b0042b227eb1ddsm500441jan.55.2023.09.21.11.29.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 Sep 2023 11:29:18 -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, 21 Sep 2023 12:29:04 -0600 Message-Id: <20230921182908.160080-5-axboe@kernel.dk> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230921182908.160080-1-axboe@kernel.dk> References: <20230921182908.160080-1-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. 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. 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 | 230 +++++++++++++++++++++++++++++++++ io_uring/futex.h | 34 +++++ io_uring/io_uring.c | 7 + io_uring/opdef.c | 23 ++++ 9 files changed, 312 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 fe1c5d4ec56c..4fc68cd6b043 100644 --- a/include/linux/io_uring_types.h +++ b/include/linux/io_uring_types.h @@ -315,6 +315,11 @@ 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 683ac2b74721..4ddd7bdbbfb8 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..4278302d212c --- /dev/null +++ b/io_uring/futex.c @@ -0,0 +1,230 @@ +// 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->fd || sqe->len || 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->futex_flags); + + 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, + futex2_to_flags(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; + + ret = futex_wake(iof->uaddr, futex2_to_flags(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 2dff4772bf14..f4198258159d 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); return ctx; @@ -2894,6 +2899,7 @@ 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) @@ -3306,6 +3312,7 @@ 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); mutex_unlock(&ctx->uring_lock); ret |= io_kill_timeouts(ctx, task, cancel_all); if (task) 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 21 18:29:05 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 13394284 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 7E3A6E7D0A9 for ; Thu, 21 Sep 2023 18:37:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229587AbjIUShr (ORCPT ); Thu, 21 Sep 2023 14:37:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35020 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229925AbjIUShZ (ORCPT ); Thu, 21 Sep 2023 14:37:25 -0400 Received: from mail-io1-xd2a.google.com (mail-io1-xd2a.google.com [IPv6:2607:f8b0:4864:20::d2a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A95BBD8684 for ; Thu, 21 Sep 2023 11:29:21 -0700 (PDT) Received: by mail-io1-xd2a.google.com with SMTP id ca18e2360f4ac-797ea09af91so18715739f.1 for ; Thu, 21 Sep 2023 11:29:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1695320960; x=1695925760; 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=OkyarrJghc8lGO3QyBOffqxkuM6y4VS1FNrUywgbd6eLH2gBeuptfipWNb37WvyKRl 69hRMuQOTTrrBPt4/pHvw6Hkw9+Spqdcw7S2Nmy84ielPmjMsUmO7fzrvam2kz45Utwj PEaxUZzV8Rir9QoJYcxCYRP2RIYfoff6GZkeexm33xiWiqUYfo3T4n8JqQeg1PYWpB6g pE8fjNTk3k/VxvzSB+AzWlQ3uKEaa1kxp5MVxuZHOLcHuJcopOWRbORGw/TL+zouKcsV laQdtc5JHhG33+uJxwrLblO1S8aikB2D0Z1ld4VLhaAUJmehbJgGUPW1G2nNYz0hTmGH I5tQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695320960; x=1695925760; 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=eMg5qDLLqGdyYEOfNih3qEbhqQFNn4ZTiNBzqGoI4l0AVJNbr45Oaq+5EV+qcmCXEd Y/Aqx0Y3ikdeHJeUt3I0hooLF+9UbiGOTWLAamrjwfzZ0mLawjYB1I338Rik/ub6C/vY INrS3BnXTLUZGlOq/H/De63F9UIm773S66hf1Qr0sRZBsEL1NDxxd6P8qABwjhL9Sqt3 joEe9i2bdQRrSPHgc6mN93FO7F0mGiitjCPAlUBp87CAAVzA9bVTLuGOzan1yUuvMIiN pYT+e7WZOyNlmHSUWh+45H2k5rBiRog7XTKIPAjGiD7azgWaofadC3nKxlSOo/kDsmde l6/w== X-Gm-Message-State: AOJu0Yy2syhiAaOo/o0TECH+nwR/ktb9BXzCyI9ClLsfz91864JyRlJ0 +8zLg7pggfZ+sNOcco/vGQxDfkF/y9mgidaA3KddeQ== X-Google-Smtp-Source: AGHT+IGEmDLrknCJWhtuHHjd+XxE0eC63PZU4o+EXvbeYFQhG7p6PVTG6rxtLvReKvtC4CGfhbJKLQ== X-Received: by 2002:a6b:c885:0:b0:79f:8cd3:fd0e with SMTP id y127-20020a6bc885000000b0079f8cd3fd0emr2093182iof.1.1695320960509; Thu, 21 Sep 2023 11:29:20 -0700 (PDT) Received: from localhost.localdomain ([96.43.243.2]) by smtp.gmail.com with ESMTPSA id o25-20020a02c6b9000000b0042b227eb1ddsm500441jan.55.2023.09.21.11.29.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 Sep 2023 11:29:19 -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, 21 Sep 2023 12:29:05 -0600 Message-Id: <20230921182908.160080-6-axboe@kernel.dk> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230921182908.160080-1-axboe@kernel.dk> References: <20230921182908.160080-1-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 21 18:29:06 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 13394283 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 5DF52E7D0A5 for ; Thu, 21 Sep 2023 18:37:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230359AbjIUSho (ORCPT ); Thu, 21 Sep 2023 14:37:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53322 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229745AbjIUSh0 (ORCPT ); Thu, 21 Sep 2023 14:37:26 -0400 Received: from mail-il1-x135.google.com (mail-il1-x135.google.com [IPv6:2607:f8b0:4864:20::135]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D5523D8686 for ; Thu, 21 Sep 2023 11:29:22 -0700 (PDT) Received: by mail-il1-x135.google.com with SMTP id e9e14a558f8ab-34e1757fe8fso1016945ab.0 for ; Thu, 21 Sep 2023 11:29:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1695320962; x=1695925762; 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=ouP89gePGLkXltybMGwkkustlfFAplUbJ4vP8U3TPcA3954wsu06QRtfnzwyvbYSYs QTVHkUdd32WVcNpJRncn7PZABjuOL6kSBVZA5/n2nwrpfc7UspeBjKI2sCPmEM3Kt5zW wHrwgAgk5ePJk4X5bYIyrevgGO5xLjj+P3TuE6Qn0T6aZvpAevB2QEv5ucKh70Y5YtCh /pwmK27WAxolaya57PNG4z/YSDrVzW8q3s7bm6oHwrL/c2etyw+ELu4SDQrAtVbwrzqd XjerkcEb5mbjB9u9WLAcyoW3KquEhxUKzGQ3PT9ROfv2DZiDl01XgicGqolS6PWTRO1d XnWQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695320962; x=1695925762; 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=EUXCBcfH3quxwkUgC5hxRXArn6Pxanjh2nDMER3/8UU1jwAu+huxWH6bWJR0/Ay3M5 +I+g+E2MY6BG4Yo97vmrXFS5KTN6mGnU+P/Bb6wGQjpQxdDeP+CT7L3df9oXgXaiNycm YEeBMsdPgQRo9zfH5YElrC0zaUbZNujKjUEF66tkben9AVl1w0iwoNHKm3JKtoGlOYHU ung5cx00B6R75ARyO+YKl3IEftr7tghdAMK58xXOdj1X1dEIheTnRno3tDNseVBLzJPp 92c/3iqoH3ROOw8Anhua0fSG6rbKF8wnK6A8N7HoMNZ6Qf1yp4Nx3fl8j5VrQCtn/H1s 68kw== X-Gm-Message-State: AOJu0YwFlyIoWsqSxzaTAds/DS6zUcOV2h9EkVOSUHx7d5dTWdXH6mxG 4UQl954UYBoVnVlyMV2PWyVPQ8GsZ7hSg9CnwbyBFA== X-Google-Smtp-Source: AGHT+IH0d1Lv9v5XvuHBRWZ4j3Pa5hUPuJ0lr8dkl2Yd+m6TonTxY7UwEf5Qp3o95XPyf+oRWhbkLA== X-Received: by 2002:a92:c52d:0:b0:34f:7ba2:50e8 with SMTP id m13-20020a92c52d000000b0034f7ba250e8mr6203745ili.2.1695320961817; Thu, 21 Sep 2023 11:29:21 -0700 (PDT) Received: from localhost.localdomain ([96.43.243.2]) by smtp.gmail.com with ESMTPSA id o25-20020a02c6b9000000b0042b227eb1ddsm500441jan.55.2023.09.21.11.29.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 Sep 2023 11:29:21 -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, 21 Sep 2023 12:29:06 -0600 Message-Id: <20230921182908.160080-7-axboe@kernel.dk> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230921182908.160080-1-axboe@kernel.dk> References: <20230921182908.160080-1-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 21 18:29:07 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 13394281 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 6DFA3E7D0A7 for ; Thu, 21 Sep 2023 18:37:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229745AbjIUShp (ORCPT ); Thu, 21 Sep 2023 14:37:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35040 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229847AbjIUSh0 (ORCPT ); Thu, 21 Sep 2023 14:37:26 -0400 Received: from mail-io1-xd2f.google.com (mail-io1-xd2f.google.com [IPv6:2607:f8b0:4864:20::d2f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 31F71D8689 for ; Thu, 21 Sep 2023 11:29:24 -0700 (PDT) Received: by mail-io1-xd2f.google.com with SMTP id ca18e2360f4ac-79f8df47bfbso10253739f.0 for ; Thu, 21 Sep 2023 11:29:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1695320963; x=1695925763; 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=h5zvPxbWi+KBRxy2l33P4Ql1YrEkI5Vx8JkaX3wnEgJgrTip2d0QcU61NZKFXB/ZT4 +bilLkvNep0yTxPjbCHKLlY5A6YkiwfKVWsjTCN7ksJCuRSiqvnfLqwvppLCoYEGJumu vuCHLIx2ifF+PsvY37r0fd4azPnN+TqB0WDk7j8Ihho6HeE5uWIJWsTkjqFQWxL2gWij 7Uts5c0xhdZOb0cKv63m1Xo+Sbkz1cEZaftBB+TDUcnxnj9XXp/JM4wEU87WAGG1HeNv MU/aMdT3NIEBJh+ofW+2cCCCpQUh/fgqQoD0xZQdHisLwUt1HeO9K4ncQph9yhGJNFP7 6ZYQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695320963; x=1695925763; 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=pl0WT/i97sGm6exCPKcJT5Q1/+QQcri1oUPCiWDAtYO8ue5jGRqxFRZi9Z39yycD31 h/s3KU86kPfdV8CElUvB/FZ0PYz+AgD/nhgW2KeMApHCnFwCYB9IITZVl1BjPE+IYM+0 dRIF4yGn/EK+vp2FG2evNqNXYuOaA7h/DTfuYSL+64DVaWB1s8pYZJOtbiT5e0kw/B/j SGkh/gsvejycCqaa5PzlvpfUZZ+k8NL7oIa2ddgS9QetXyEC4WvWL16r9LxKOI6MsIIb BjaHbro3crXSmotjdeHguxbZF5N4jFn/lX1VtsT78BEoppZw5L7zIBe8zuCmFkpU2unG ZtCA== X-Gm-Message-State: AOJu0YwwK8ZOBOs5Cft+cEBpZF3uTeqgNFyE00nIS5pq4CVcvl8q0eJI ipc32+e3pj1WY58uhj8TcgTCIb/+9YZaDGr32SlmSg== X-Google-Smtp-Source: AGHT+IGg+1Bf4dt5Q006eZUcpXl2xhZHKdXAg7pZKFh2g2e8No0nMLmMw3nV+J6FY9ahF6SJxJmTuQ== X-Received: by 2002:a05:6602:3788:b0:792:7c78:55be with SMTP id be8-20020a056602378800b007927c7855bemr6834507iob.0.1695320963064; Thu, 21 Sep 2023 11:29:23 -0700 (PDT) Received: from localhost.localdomain ([96.43.243.2]) by smtp.gmail.com with ESMTPSA id o25-20020a02c6b9000000b0042b227eb1ddsm500441jan.55.2023.09.21.11.29.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 Sep 2023 11:29:22 -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 7/8] futex: make the vectored futex operations available Date: Thu, 21 Sep 2023 12:29:07 -0600 Message-Id: <20230921182908.160080-8-axboe@kernel.dk> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230921182908.160080-1-axboe@kernel.dk> References: <20230921182908.160080-1-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 21 18:29:08 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 13394285 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 96F93E7D0A8 for ; Thu, 21 Sep 2023 18:37:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229927AbjIUShq (ORCPT ); Thu, 21 Sep 2023 14:37:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34974 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229587AbjIUSh1 (ORCPT ); Thu, 21 Sep 2023 14:37:27 -0400 Received: from mail-io1-xd31.google.com (mail-io1-xd31.google.com [IPv6:2607:f8b0:4864:20::d31]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A9D10D868F for ; Thu, 21 Sep 2023 11:29:25 -0700 (PDT) Received: by mail-io1-xd31.google.com with SMTP id ca18e2360f4ac-79f8df47bfbso10254439f.0 for ; Thu, 21 Sep 2023 11:29:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1695320964; x=1695925764; 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=T07+FrfCPjZBo72MwSk6fDllH6IdPm+PDxNrxWagj38=; b=XjA2LfKPRX+SU4/H3+AzQrupIHosj67NBFlTc+tdPDTcz80R3VLJdTkJbxnt7UBDUQ vUX1tgdxThvBw1zkH5+1zRqOkiW4z0wlx0ktvE6DHny6BykYkJAAhvWA+ubOtrpuL/8u cybB1u1BzyVqBz3TRKvMJmNixNnUZ9XEuariQQY00UzjikcFKxckzQjfqrD61y+fCmrl f4nRBls5SBjvucuEynYf1z4b2BR8c+FR071nsUQ+sDX752TYzPIPKeJGS4nxQtQZml7u E/54/7GOVAbRqLb74PFGj9B71Phh+fb9NMX+WJgyfCItr4EJTsHAGf4D+VxxHFzuTo9j vHXA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695320964; x=1695925764; 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=T07+FrfCPjZBo72MwSk6fDllH6IdPm+PDxNrxWagj38=; b=BIC5O9CK5NT9OzdkiVlh+pY82cBf+132As0/C1KKdcIWp+uku/e5oOLCjiaWWfYgpa WAcw2wsfDJqe40mgR3W2QTRW53shunuP2uqiN+oBwqw6DjPeSHmoEr1DNCfz73uCbDeB PvUU7LRpF3fK3smC8JaqbiNsKXE2aufkgUtas2AnxSBme5TTxIVWr72HovdJ/uGUZ9ib sc2EDpF2FtgAQWdH9Bb9Y7CVSOzIvefOTdblYYTbvskE6DuDWtmbZ/4lEDcsmBv/xhql JaqG/wWORhWcmys1sWnxCnJN5Mx1uMpQzk8iL65GHWlIa/2TR9LcvD0k8ZWQSj8T2jVz 3Fdg== X-Gm-Message-State: AOJu0YwgdLncItHS87JZfxL17uxF7w7TVXhdBPJfz1B9g+yJvEddTYWX UkdAJnG93UZdUCrA30SX1o8IZNuDYiyml+Egh/qM8g== X-Google-Smtp-Source: AGHT+IHHeGJYB3BCeWiqyDSINsxeVgZhZetGoHC2AFY9MnSBSKh1BEBTLr68Bh1E8VMEO0o+TJc9UQ== X-Received: by 2002:a05:6602:13c2:b0:79d:1c65:9bde with SMTP id o2-20020a05660213c200b0079d1c659bdemr8647351iov.1.1695320964457; Thu, 21 Sep 2023 11:29:24 -0700 (PDT) Received: from localhost.localdomain ([96.43.243.2]) by smtp.gmail.com with ESMTPSA id o25-20020a02c6b9000000b0042b227eb1ddsm500441jan.55.2023.09.21.11.29.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 Sep 2023 11:29:23 -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, 21 Sep 2023 12:29:08 -0600 Message-Id: <20230921182908.160080-9-axboe@kernel.dk> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230921182908.160080-1-axboe@kernel.dk> References: <20230921182908.160080-1-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 the a pointer to a struct futex_waitv array, and sqe->off must now contain the number of elements in that array. 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 | 164 ++++++++++++++++++++++++++++++++-- io_uring/futex.h | 2 + io_uring/opdef.c | 11 +++ 4 files changed, 169 insertions(+), 9 deletions(-) diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index 4ddd7bdbbfb8..172472626f5b 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 4278302d212c..0c07df8668aa 100644 --- a/io_uring/futex.c +++ b/io_uring/futex.c @@ -14,10 +14,15 @@ 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; }; struct io_futex_data { @@ -44,6 +49,13 @@ 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 +64,59 @@ 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; + struct io_ring_ctx *ctx = req->ctx; + int res = 0; - /* futex wake already done or in progress */ - if (!futex_unqueue(&ifd->q)) + io_tw_lock(ctx, ts); + + 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_claimed(struct io_futex *iof) +{ + return test_bit(0, &iof->futexv_owned); +} + +static bool io_futexv_claim(struct io_futex *iof) +{ + if (test_bit(0, &iof->futexv_owned) || + test_and_set_bit(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; } @@ -146,6 +195,54 @@ 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->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; + 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); @@ -170,6 +267,55 @@ 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); + + /* + * The above call leaves us potentially non-running. 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); + + /* + * We got woken while setting up, let that side do the completion + */ + if (io_futexv_claimed(iof)) { +skip: + io_ring_submit_unlock(ctx, issue_flags); + return IOU_ISSUE_SKIP_COMPLETE; + } + + /* + * 0 return means that we successfully setup the waiters, and that + * nobody triggered a wakeup while we were doing so. < 0 or 1 return + * is either an error or we got a wakeup while setting up. + */ + if (!ret) { + hlist_add_head(&req->hash_node, &ctx->futex_list); + goto skip; + } + + io_ring_submit_unlock(ctx, issue_flags); + if (ret < 0) + req_set_fail(req); + else if (woken != -1) + ret = woken; + io_req_set_res(req, ret, 0); + kfree(futexv); + req->flags &= ~REQ_F_ASYNC_DATA; + return IOU_OK; +} + 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)