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 X-Spam-Level: X-Spam-Status: No, score=-11.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7D27DC4363D for ; Fri, 2 Oct 2020 14:12:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3EA05206DD for ; Fri, 2 Oct 2020 14:12:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601647971; bh=lqNTdTkNdsQHcWQ/ycuvV9kZSZGTlIJnGnt90RDqrbc=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:List-ID: From; b=2NfL0nxyJChTFqQfFbLteRsGoYthp4PDE6wZP2b6t4YSx8/gG/dCwFpvqN/qTwAW7 4Ri8VLgyNdygYJ7JEyLa665r75V6CFzaEd5cm6dzRTqvJ3fvu+W+60NCFd00wGBXbE Qs5g2V4wE9NZPh2tWdvcZbvlwppCzjvy8dG/SfdA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726282AbgJBOMv (ORCPT ); Fri, 2 Oct 2020 10:12:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:51002 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726090AbgJBOMu (ORCPT ); Fri, 2 Oct 2020 10:12:50 -0400 Received: from paulmck-ThinkPad-P72.home (50-39-104-11.bvtn.or.frontiernet.net [50.39.104.11]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4411C206DB; Fri, 2 Oct 2020 14:12:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601647970; bh=lqNTdTkNdsQHcWQ/ycuvV9kZSZGTlIJnGnt90RDqrbc=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:From; b=usUyOsupMwL4xMxZfBJFg8t60KKwuUfnFAwSuT6FAfPylsUSQLmCNYfbQawOzfIFQ SsGAbLj/NyS1ZVD1+OwPxiqVE95X+ragy7GFkzcnhLrVJ7MYOhEvItErsv94nNC3Ez Ryw0XZvryq1L6yJDMEf9xMB8XHSbYFpI7SyxphQU= Received: by paulmck-ThinkPad-P72.home (Postfix, from userid 1000) id 097BD3522838; Fri, 2 Oct 2020 07:12:50 -0700 (PDT) Date: Fri, 2 Oct 2020 07:12:50 -0700 From: "Paul E. McKenney" To: Michal Hocko Cc: rcu@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com, mingo@kernel.org, jiangshanlai@gmail.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, fweisbec@gmail.com, oleg@redhat.com, joel@joelfernandes.org, mgorman@techsingularity.net, torvalds@linux-foundation.org, "Uladzislau Rezki (Sony)" Subject: Re: [PATCH tip/core/rcu 14/15] rcu/tree: Allocate a page when caller is preemptible Message-ID: <20201002141250.GH29330@paulmck-ThinkPad-P72> Reply-To: paulmck@kernel.org References: <20200928233041.GA23230@paulmck-ThinkPad-P72> <20200928233102.24265-14-paulmck@kernel.org> <20200929120756.GC2277@dhcp22.suse.cz> <20200930015327.GX29330@paulmck-ThinkPad-P72> <20200930084139.GN2277@dhcp22.suse.cz> <20200930232154.GA29330@paulmck-ThinkPad-P72> <20201001090220.GA22560@dhcp22.suse.cz> <20201001162709.GD29330@paulmck-ThinkPad-P72> <20201002065746.GA20872@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201002065746.GA20872@dhcp22.suse.cz> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: rcu@vger.kernel.org On Fri, Oct 02, 2020 at 08:57:46AM +0200, Michal Hocko wrote: > On Thu 01-10-20 09:27:09, Paul E. McKenney wrote: > [...] > > commit ea5c19d21233b5e8d3d06c0d4ecd6be9f2829dc3 > > Author: Paul E. McKenney > > Date: Thu Oct 1 09:24:40 2020 -0700 > > > > kvfree_rcu: Use __GFP_NOMEMALLOC for single-argument kvfree_rcu() > > > > This commit applies the __GFP_NOMEMALLOC gfp flag to memory allocations > > carried out by the single-argument variant of kvfree_rcu(), thus avoiding > > this can-sleep code path from dipping into the emergency reserves. > > > > Suggested-by: Michal Hocko > > Signed-off-by: Paul E. McKenney > > LGTM. At least for this one I feel competent to give you > Acked-by: Michal Hocko Thank you very much! I will apply this on the next rebase later today, Pacific Time. Thanx, Paul > > diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c > > index 242f0f0..6132452 100644 > > --- a/kernel/rcu/tree.c > > +++ b/kernel/rcu/tree.c > > @@ -3364,7 +3364,8 @@ add_ptr_to_bulk_krc_lock(struct kfree_rcu_cpu **krcp, > > { > > struct kvfree_rcu_bulk_data *bnode; > > bool can_alloc_page = preemptible(); > > - gfp_t gfp = (can_sleep ? GFP_KERNEL | __GFP_RETRY_MAYFAIL : GFP_ATOMIC) | __GFP_NOWARN; > > + gfp_t gfp = (can_sleep ? GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOMEMALLOC > > + : GFP_ATOMIC) | __GFP_NOWARN; > > int idx; > > > > *krcp = krc_this_cpu_lock(flags); > > -- > Michal Hocko > SUSE Labs