From patchwork Sat May 27 09:19:04 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Li Nan X-Patchwork-Id: 13257604 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 016B3C77B7C for ; Sat, 27 May 2023 09:20:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231925AbjE0JUw (ORCPT ); Sat, 27 May 2023 05:20:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60914 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231775AbjE0JUv (ORCPT ); Sat, 27 May 2023 05:20:51 -0400 Received: from dggsgout11.his.huawei.com (dggsgout11.his.huawei.com [45.249.212.51]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9D6EEE3; Sat, 27 May 2023 02:20:48 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.30.67.153]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4QSx9859Fnz4f3nTh; Sat, 27 May 2023 17:20:44 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.127.227]) by APP4 (Coremail) with SMTP id gCh0CgBH_rFoy3FkYoRGKQ--.53803S4; Sat, 27 May 2023 17:20:42 +0800 (CST) From: linan666@huaweicloud.com To: tj@kernel.org, josef@toxicpanda.com, axboe@kernel.dk Cc: cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linan122@huawei.com, yukuai3@huawei.com, yi.zhang@huawei.com, houtao1@huawei.com, yangerkun@huawei.com Subject: [PATCH] blk-iocost: use spin_lock_irqsave in adjust_inuse_and_calc_cost Date: Sat, 27 May 2023 17:19:04 +0800 Message-Id: <20230527091904.3001833-1-linan666@huaweicloud.com> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 X-CM-TRANSID: gCh0CgBH_rFoy3FkYoRGKQ--.53803S4 X-Coremail-Antispam: 1UD129KBjvJXoW3AFy3Jr45Cw15Gr1rtFy8uFg_yoW7Xw1kpF 43Kry3Ar4jyF10qa10kr1Yqrs8C398u3y7Gr93Ga1fAF45ur13X3WxAFy09FWYgrW3CFW2 qF1kt3yrAFsxAw7anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUU92b4IE77IF4wAFF20E14v26r4j6ryUM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rwA2F7IY1VAKz4 vEj48ve4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7Cj xVAFwI0_Gr1j6F4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x 0267AKxVW0oVCq3wAac4AC62xK8xCEY4vEwIxC4wAS0I0E0xvYzxvE52x082IY62kv0487 Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aV AFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7VAKI48JM4IIrI8v6xkF 7I0E8cxan2IY04v7M4kE6xkIj40Ew7xC0wCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7x kEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E 67AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCw CI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAIcVCF04k26cxKx2IYs7xG6rW3Jr0E 3s1lIxAIcVC2z280aVAFwI0_Gr0_Cr1lIxAIcVC2z280aVCY1x0267AKxVW8Jr0_Cr1UYx BIdaVFxhVjvjDU0xZFpf9x07UKoGdUUUUU= X-CM-SenderInfo: polqt0awwwqx5xdzvxpfor3voofrz/ X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org From: Li Nan adjust_inuse_and_calc_cost() use spin_lock_irq() and IRQ will be enabled when unlock. DEADLOCK might happen if we have held other locks and disabled IRQ before invoking it. Fix it by using spin_lock_irqsave() instead, which can keep IRQ state consistent with before when unlock. ================================ WARNING: inconsistent lock state 5.10.0-02758-g8e5f91fd772f #26 Not tainted -------------------------------- inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. kworker/2:3/388 [HC0[0]:SC0[0]:HE0:SE1] takes: ffff888118c00c28 (&bfqd->lock){?.-.}-{2:2}, at: spin_lock_irq ffff888118c00c28 (&bfqd->lock){?.-.}-{2:2}, at: bfq_bio_merge+0x141/0x390 {IN-HARDIRQ-W} state was registered at: __lock_acquire+0x3d7/0x1070 lock_acquire+0x197/0x4a0 __raw_spin_lock_irqsave _raw_spin_lock_irqsave+0x3b/0x60 bfq_idle_slice_timer_body bfq_idle_slice_timer+0x53/0x1d0 __run_hrtimer+0x477/0xa70 __hrtimer_run_queues+0x1c6/0x2d0 hrtimer_interrupt+0x302/0x9e0 local_apic_timer_interrupt __sysvec_apic_timer_interrupt+0xfd/0x420 run_sysvec_on_irqstack_cond sysvec_apic_timer_interrupt+0x46/0xa0 asm_sysvec_apic_timer_interrupt+0x12/0x20 irq event stamp: 837522 hardirqs last enabled at (837521): [] __raw_spin_unlock_irqrestore hardirqs last enabled at (837521): [] _raw_spin_unlock_irqrestore+0x3d/0x40 hardirqs last disabled at (837522): [] __raw_spin_lock_irq hardirqs last disabled at (837522): [] _raw_spin_lock_irq+0x43/0x50 softirqs last enabled at (835852): [] __do_softirq+0x558/0x8ec softirqs last disabled at (835845): [] asm_call_irq_on_stack+0xf/0x20 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&bfqd->lock); lock(&bfqd->lock); *** DEADLOCK *** 3 locks held by kworker/2:3/388: #0: ffff888107af0f38 ((wq_completion)kthrotld){+.+.}-{0:0}, at: process_one_work+0x742/0x13f0 #1: ffff8881176bfdd8 ((work_completion)(&td->dispatch_work)){+.+.}-{0:0}, at: process_one_work+0x777/0x13f0 #2: ffff888118c00c28 (&bfqd->lock){?.-.}-{2:2}, at: spin_lock_irq #2: ffff888118c00c28 (&bfqd->lock){?.-.}-{2:2}, at: bfq_bio_merge+0x141/0x390 stack backtrace: CPU: 2 PID: 388 Comm: kworker/2:3 Not tainted 5.10.0-02758-g8e5f91fd772f #26 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 Workqueue: kthrotld blk_throtl_dispatch_work_fn Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x107/0x167 print_usage_bug valid_state mark_lock_irq.cold+0x32/0x3a mark_lock+0x693/0xbc0 mark_held_locks+0x9e/0xe0 __trace_hardirqs_on_caller lockdep_hardirqs_on_prepare.part.0+0x151/0x360 trace_hardirqs_on+0x5b/0x180 __raw_spin_unlock_irq _raw_spin_unlock_irq+0x24/0x40 spin_unlock_irq adjust_inuse_and_calc_cost+0x4fb/0x970 ioc_rqos_merge+0x277/0x740 __rq_qos_merge+0x62/0xb0 rq_qos_merge bio_attempt_back_merge+0x12c/0x4a0 blk_mq_sched_try_merge+0x1b6/0x4d0 bfq_bio_merge+0x24a/0x390 __blk_mq_sched_bio_merge+0xa6/0x460 blk_mq_sched_bio_merge blk_mq_submit_bio+0x2e7/0x1ee0 __submit_bio_noacct_mq+0x175/0x3b0 submit_bio_noacct+0x1fb/0x270 blk_throtl_dispatch_work_fn+0x1ef/0x2b0 process_one_work+0x83e/0x13f0 process_scheduled_works worker_thread+0x7e3/0xd80 kthread+0x353/0x470 ret_from_fork+0x1f/0x30 Fixes: b0853ab4a238 ("blk-iocost: revamp in-period donation snapbacks") Signed-off-by: Li Nan Reviewed-by: Yu Kuai Acked-by: Tejun Heo --- block/blk-iocost.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/block/blk-iocost.c b/block/blk-iocost.c index 82e634d552d9..7581893e0d82 100644 --- a/block/blk-iocost.c +++ b/block/blk-iocost.c @@ -2438,6 +2438,7 @@ static u64 adjust_inuse_and_calc_cost(struct ioc_gq *iocg, u64 vtime, u32 hwi, adj_step; s64 margin; u64 cost, new_inuse; + unsigned long flags; current_hweight(iocg, NULL, &hwi); old_hwi = hwi; @@ -2456,11 +2457,11 @@ static u64 adjust_inuse_and_calc_cost(struct ioc_gq *iocg, u64 vtime, iocg->inuse == iocg->active) return cost; - spin_lock_irq(&ioc->lock); + spin_lock_irqsave(&ioc->lock, flags); /* we own inuse only when @iocg is in the normal active state */ if (iocg->abs_vdebt || list_empty(&iocg->active_list)) { - spin_unlock_irq(&ioc->lock); + spin_unlock_irqrestore(&ioc->lock, flags); return cost; } @@ -2481,7 +2482,7 @@ static u64 adjust_inuse_and_calc_cost(struct ioc_gq *iocg, u64 vtime, } while (time_after64(vtime + cost, now->vnow) && iocg->inuse != iocg->active); - spin_unlock_irq(&ioc->lock); + spin_unlock_irqrestore(&ioc->lock, flags); TRACE_IOCG_PATH(inuse_adjust, iocg, now, old_inuse, iocg->inuse, old_hwi, hwi);