From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7038AC021B8 for ; Wed, 26 Feb 2025 15:51:47 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E668128000A; Wed, 26 Feb 2025 10:51:46 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id E2095280008; Wed, 26 Feb 2025 10:51:46 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CDD5428000A; Wed, 26 Feb 2025 10:51:46 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 5AF80280008 for ; Wed, 26 Feb 2025 10:51:46 -0500 (EST) Received: from smtpin17.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 832381CA456 for ; Wed, 26 Feb 2025 15:51:45 +0000 (UTC) X-FDA: 83162536170.17.5B627BB Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf11.hostedemail.com (Postfix) with ESMTP id 7293840022 for ; Wed, 26 Feb 2025 15:51:43 +0000 (UTC) Authentication-Results: imf11.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b="J/wtZVHD"; spf=pass (imf11.hostedemail.com: domain of kbusch@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=kbusch@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1740585103; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=X3/aU7lmziMQt0GRz0RQ3LAAu7nNKTl6wiF2Hu6gTiY=; b=t+gEVUO8oo0YAaHdPcc6jnfM8VfvdRDZLt0PAOEcFM5AOL/olrCsUmOCo0qCLbVM4OCvWk Yd/yhEjAvf58wdMkSvJv5k0aXVKKU3nVWlJ7qqJc0zomyaJkOxtdaPniD+VxsbKmRGiW7I we1VUNNp4gn84f5BHsAApkcUMWrcwv4= ARC-Authentication-Results: i=1; imf11.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b="J/wtZVHD"; spf=pass (imf11.hostedemail.com: domain of kbusch@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=kbusch@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1740585103; a=rsa-sha256; cv=none; b=8SuUUsAJ7gDWYF+naqz9WVQRa+Cc6VWrYQwOprPmg59tS3uolRjBFBqVUpH+OPMJfKHXYz Z2clwZNO3jybSwIjgZx0q5j617gZcA9gdjsiHAYIcLTVuu1IRyhhdFY96OpuIth8hyw+pw bmIwv7J9WmHA9wGVT0KK3E2alsLC5uQ= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id CCED35C5D9D; Wed, 26 Feb 2025 15:51:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6B506C4CED6; Wed, 26 Feb 2025 15:51:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1740585101; bh=dystgmSF/TCO8+uxX80prLd9mmlEKMg2wmXGUfrA378=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=J/wtZVHDOkcHb7Wj/XoTGhFH+jxWlVoY/3JmSc85XIsQBGuD3Gxmv325CJ64iW62I sLn3ueeKUKKEkkKxXG1r3zuySs0GQNjC2xBBRb9EJlIYFWS6GbsPUfrvvmRV2a6dvf XZAXHrOF0l30oLCks2wqUQnLjyU0cWBHUEWG6Y+ePaw0Mbm1ktvpkoGZBHjhBfKYwi B7uFEabl3vRtrjctHeND1AeJpBZ72c+gaKOg/ZzNTibJxVnK7fN2grML69IQB6MsBH BpVyRJswqscjYs7RJNdAbTx/Zlf0XO+ANH2X/3e4oTROLG/KcresZY91V6qxiCWYPA BqIqJwDfWeC1Q== Date: Wed, 26 Feb 2025 08:51:37 -0700 From: Keith Busch To: Uladzislau Rezki Cc: Keith Busch , Vlastimil Babka , "Paul E. McKenney" , Joel Fernandes , Josh Triplett , Boqun Feng , Christoph Lameter , David Rientjes , Steven Rostedt , Mathieu Desnoyers , Lai Jiangshan , Zqiang , Julia Lawall , Jakub Kicinski , "Jason A. Donenfeld" , Andrew Morton , Roman Gushchin , Hyeonggon Yoo <42.hyeyoo@gmail.com>, linux-mm@kvack.org, linux-kernel@vger.kernel.org, rcu@vger.kernel.org, Alexander Potapenko , Marco Elver , Dmitry Vyukov , kasan-dev@googlegroups.com, Jann Horn , Mateusz Guzik , linux-nvme@lists.infradead.org, leitao@debian.org Subject: Re: [PATCH v2 6/7] mm, slab: call kvfree_rcu_barrier() from kmem_cache_destroy() Message-ID: References: <20240807-b4-slab-kfree_rcu-destroy-v2-0-ea79102f428c@suse.cz> <20240807-b4-slab-kfree_rcu-destroy-v2-6-ea79102f428c@suse.cz> <2811463a-751f-4443-9125-02628dc315d9@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspam-User: X-Rspamd-Queue-Id: 7293840022 X-Stat-Signature: j3nxk71wzbysef37shmf9uua5sojokdo X-Rspamd-Server: rspam03 X-HE-Tag: 1740585103-611496 X-HE-Meta: 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 P1g1PAx8 nFJJivquBM3WUxOZZ0BjUSMGSCQ1auzAeYxW2Ew6Z/2R2T79v1YrwZpm/GTfDGjeH8fKzxXuIR+D9K2XOqtLT3ITUlbRBMKcHmnahvjxMymsU363x7wRNyNtx9loG/d7OxSpmLqGmkwFnwLmKu2uWcWnm81fzA5zCbceIB2R2mO8kEH3hb929HIFT/BD1Ev/+i+wLPoI9ImKAXKaTsiZZ5D+xcyaX3L5rvTcYkuWia0DjBMMT3eJgMWvsb6LPY8IIfCcaQYndqXY8KrZJ0NweG2p6UiA3usxfqSxDx9x4LaL5ql0kPv/uvHQUxB1ZX2j0l5BXEgLVOCBs7tD8goqdsrmW8Bs7Ju17x5zFRgpxdqLwrlRNUWdGJrT+q2tnIxyqwJsIou+tPjKcPEw= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, Feb 25, 2025 at 07:21:19PM +0100, Uladzislau Rezki wrote: > WQ_MEM_RECLAIM-patch fixes this for me: This is successful with the new kuint test for me as well. I can't readily test this in production where I first learned of this issue (at least not in the near term), but for what it's worth, this looks like a good change to me. Reviewed-by: Keith Busch > > diff --git a/mm/slab_common.c b/mm/slab_common.c > index 4030907b6b7d..1b5ed5512782 100644 > --- a/mm/slab_common.c > +++ b/mm/slab_common.c > @@ -1304,6 +1304,8 @@ module_param(rcu_min_cached_objs, int, 0444); > static int rcu_delay_page_cache_fill_msec = 5000; > module_param(rcu_delay_page_cache_fill_msec, int, 0444); > > +static struct workqueue_struct *rcu_reclaim_wq; > + > /* Maximum number of jiffies to wait before draining a batch. */ > #define KFREE_DRAIN_JIFFIES (5 * HZ) > #define KFREE_N_BATCHES 2 > @@ -1632,10 +1634,10 @@ __schedule_delayed_monitor_work(struct kfree_rcu_cpu *krcp) > if (delayed_work_pending(&krcp->monitor_work)) { > delay_left = krcp->monitor_work.timer.expires - jiffies; > if (delay < delay_left) > - mod_delayed_work(system_unbound_wq, &krcp->monitor_work, delay); > + mod_delayed_work(rcu_reclaim_wq, &krcp->monitor_work, delay); > return; > } > - queue_delayed_work(system_unbound_wq, &krcp->monitor_work, delay); > + queue_delayed_work(rcu_reclaim_wq, &krcp->monitor_work, delay); > } > > static void > @@ -1733,7 +1735,7 @@ kvfree_rcu_queue_batch(struct kfree_rcu_cpu *krcp) > // "free channels", the batch can handle. Break > // the loop since it is done with this CPU thus > // queuing an RCU work is _always_ success here. > - queued = queue_rcu_work(system_unbound_wq, &krwp->rcu_work); > + queued = queue_rcu_work(rcu_reclaim_wq, &krwp->rcu_work); > WARN_ON_ONCE(!queued); > break; > } > @@ -1883,7 +1885,7 @@ run_page_cache_worker(struct kfree_rcu_cpu *krcp) > if (rcu_scheduler_active == RCU_SCHEDULER_RUNNING && > !atomic_xchg(&krcp->work_in_progress, 1)) { > if (atomic_read(&krcp->backoff_page_cache_fill)) { > - queue_delayed_work(system_unbound_wq, > + queue_delayed_work(rcu_reclaim_wq, > &krcp->page_cache_work, > msecs_to_jiffies(rcu_delay_page_cache_fill_msec)); > } else { > @@ -2120,6 +2122,10 @@ void __init kvfree_rcu_init(void) > int i, j; > struct shrinker *kfree_rcu_shrinker; > > + rcu_reclaim_wq = alloc_workqueue("rcu_reclaim", > + WQ_UNBOUND | WQ_MEM_RECLAIM, 0); > + WARN_ON(!rcu_reclaim_wq); > + > /* Clamp it to [0:100] seconds interval. */ > if (rcu_delay_page_cache_fill_msec < 0 || > rcu_delay_page_cache_fill_msec > 100 * MSEC_PER_SEC) { >