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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 04052C18E7C for ; Wed, 26 Feb 2025 15:53:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:Date:From:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=eswWLfkEnQpdtu+isG+K14u+ZfJSvAbvqWCgztSMnzs=; b=1+f0y8dd9kbM/Go3fVmla6XM8w rkhbkIVOXXGFnFERwN37CAxYQQ5RcAvqXH/Aad339RgQ2ntfQr451MpjTRxmEa0ZrXOcs3QVTTpIf OzMpCdgAQ05+/Gno9S07ojKojmjlJRYqErEC50eFkN12X8K6quj0/0MMSCcL2gDqgbHGYVbM84oU0 FsavzuOHfRqAX1YvSDo+0HJFHvShYx0hGTuLM341q68Nlk+23JJP1JBirkrmtAtwWwNOw/rb7nNy7 m+DvafjiyXU9HILbEfizFESlhBJxCTRpQ5VPhFw7B3dDwUlnnVxeu7tkqG8kXHvwB23f4nRUuHHyR f3ZsQuAw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tnJif-00000004PTL-1T8X; Wed, 26 Feb 2025 15:53:09 +0000 Received: from mail-lj1-x235.google.com ([2a00:1450:4864:20::235]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tnIRI-000000045rl-0G2D for linux-nvme@lists.infradead.org; Wed, 26 Feb 2025 14:31:09 +0000 Received: by mail-lj1-x235.google.com with SMTP id 38308e7fff4ca-30a2f240156so72204771fa.3 for ; Wed, 26 Feb 2025 06:31:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1740580266; x=1741185066; darn=lists.infradead.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:date:from:from:to:cc:subject:date:message-id:reply-to; bh=eswWLfkEnQpdtu+isG+K14u+ZfJSvAbvqWCgztSMnzs=; b=BLTg8PpVThnATFAZe6yqsUx3WAlSEHyowniF7eke/ajLWAxC5R0SwI1Dzt1iQ+PjnN XaXj5F7F/L2e5mugFyT0LOzyQrgOljHc2YfUMKIu0EW/ER2I6Qup0t2Ft1ON808zPgPs xnfmR8XKB8cwrRv7M9l7VzGWw3WJH0cfxRRIBe1fbEBiNR8e3+JhQBC7LG/7FsqPs3Ur BRCkbw7N6CsnnIBoMuj1m0dF3mtd2bFpepTb31IG/VrB5QccdQ7sjO+R78nXZOJ+0xAR fA4roVtKm7qYHsSFJvnQ9KC+NyhHgFI4rRHgtZopGRQXHh0LMVfrvdyGdOif38kpRod7 Q99A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1740580266; x=1741185066; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:date:from:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=eswWLfkEnQpdtu+isG+K14u+ZfJSvAbvqWCgztSMnzs=; b=veLJVhHFQ8g7CFJVjpxgvtIUhUiBOIfbqTolGAn3TKqO3xArFOp2LPQRDsJu5NykIL +gZOdU2qFYx9HMnbfW9/TL4CxFKNBe9iov2fik+YHyRfIW2jGxvuYek5mmhaSWKhtDLS nASx6rYWPzFgAozLk2aNlNDcM7SngZcsRuTFOys/qrEIyfvc9XCeAq4UX7VkOndVNXCx G+dI6nfs5UP1fDztrk2CJJkCLInzqXZAf/40+Nm+ZjY9UTkl3PtxZJvl+3p2gx1/6IBa BHzfeVNOHbqMFOeTeO2z2toec5xGuNlAdE2U6gRwXoVKYVZdd7fdc22xSOHra16rrQ4w TOKg== X-Forwarded-Encrypted: i=1; AJvYcCWKxzSg/8EjECoMXjjV0EJ59op0/Mk7xtig5T/hviO/EF9reiMF6jhKdDz+dSrZjf4ZU+b0Ym9Z+mut@lists.infradead.org X-Gm-Message-State: AOJu0YxG6TSu5UhM3a7hVUyIq7OpB5NOeFsRKMsLl5QJWs29HvzAe1+5 KqmMB25E1epX5R1j3EziajoDBP0H5buKHgQSRnG2pfr3lw/jLQq1 X-Gm-Gg: ASbGnctZniZsv/zduCWoLAMkOuYXArAXv+dvZjvjsCm/iXF54UdiXtrXyMaZg4Eu0MN R/60Yfrk3HXRZPgsZ9TJfl1VGdRvlE7jMnyOi4aTUzdtZgIlX2/z9dk6syZtZZDC50Wwf/66whU 51WQ/wgjrjpmL5FVKRIiFTBHBJEOiDW9R3vBo8Xks4yuaKyNGxZp8eIE/OWF689BlqHrvVgK8ed afXnmSLfH2NniDBoqfACgiFUnpsvnf+fPrfda3ElDVk2sVPpp02JhfeJz7OHYVpejE7dvdDbOur 0q5JvMHGBUWfjSiCsmZScBaOwf3osXDmTdBtKGlyPMmIUSlr X-Google-Smtp-Source: AGHT+IGJW1NAlywvROVKX3Fy47FV/keZ7CVdQO/S4ffINoO6dO3Lou+LoCLXMQL+bGSH5kPPCn5/wg== X-Received: by 2002:a2e:9a98:0:b0:307:5879:e7d8 with SMTP id 38308e7fff4ca-30b792cb29cmr26025521fa.30.1740580265244; Wed, 26 Feb 2025 06:31:05 -0800 (PST) Received: from pc636 (host-95-203-6-24.mobileonline.telia.com. [95.203.6.24]) by smtp.gmail.com with ESMTPSA id 38308e7fff4ca-30a819f5e4asm5422341fa.63.2025.02.26.06.31.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 26 Feb 2025 06:31:04 -0800 (PST) From: Uladzislau Rezki X-Google-Original-From: Uladzislau Rezki Date: Wed, 26 Feb 2025 15:31:01 +0100 To: Vlastimil Babka Cc: Uladzislau Rezki , Keith Busch , "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-v2-6-ea79102f428c@suse.cz> <2811463a-751f-4443-9125-02628dc315d9@suse.cz> <8d7aabb2-2836-4c09-9fc7-8bde271e7f23@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8d7aabb2-2836-4c09-9fc7-8bde271e7f23@suse.cz> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250226_063108_099427_DD1219A8 X-CRM114-Status: GOOD ( 23.91 ) X-Mailman-Approved-At: Wed, 26 Feb 2025 07:53:07 -0800 X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Wed, Feb 26, 2025 at 11:59:53AM +0100, Vlastimil Babka wrote: > On 2/25/25 7:21 PM, Uladzislau Rezki wrote: > >> > > WQ_MEM_RECLAIM-patch fixes this for me: > > Sounds good, can you send a formal patch then? > Do you mean both? Test case and fix? I can :) > Some nits below: > > > > > 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", > > Should we name it "kvfree_rcu_reclaim"? rcu_reclaim sounds too generic > as if it's part of rcu itself? > > > + WQ_UNBOUND | WQ_MEM_RECLAIM, 0); > > Do we want WQ_SYSFS? Or maybe only when someone asks, with a use case? > If someone asks, IMO. -- Uladzislau Rezki