From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751068AbdKTJZb (ORCPT ); Mon, 20 Nov 2017 04:25:31 -0500 Received: from mx2.suse.de ([195.135.220.15]:57693 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750764AbdKTJZa (ORCPT ); Mon, 20 Nov 2017 04:25:30 -0500 Date: Mon, 20 Nov 2017 10:25:26 +0100 From: Michal Hocko To: Christoph Hellwig Cc: Tetsuo Handa , Minchan Kim , Huang Ying , Mel Gorman , Vladimir Davydov , Johannes Weiner , Andrew Morton , Shakeel Butt , Greg Thelen , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] mm,vmscan: Kill global shrinker lock. Message-ID: <20171120092526.llj2q3lqbbxwn4g4@dhcp22.suse.cz> References: <1510609063-3327-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp> <20171117173521.GA21692@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171117173521.GA21692@infradead.org> User-Agent: NeoMutt/20170609 (1.8.3) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri 17-11-17 09:35:21, Christoph Hellwig wrote: > On Tue, Nov 14, 2017 at 06:37:42AM +0900, Tetsuo Handa wrote: > > Since do_shrink_slab() can reschedule, we cannot protect shrinker_list > > using one RCU section. But using atomic_inc()/atomic_dec() for each > > do_shrink_slab() call will not impact so much. > > But you could use SRCU.. Davidlohr has tried that already http://lkml.kernel.org/r/1434398602.1903.15.camel@stgolabs.net and failed. Doing SRCU inside core kernel is not seen with a great support... -- Michal Hocko SUSE Labs From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f69.google.com (mail-wm0-f69.google.com [74.125.82.69]) by kanga.kvack.org (Postfix) with ESMTP id ABC176B0038 for ; Mon, 20 Nov 2017 04:25:30 -0500 (EST) Received: by mail-wm0-f69.google.com with SMTP id v186so6017986wma.9 for ; Mon, 20 Nov 2017 01:25:30 -0800 (PST) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id i10si6176037edk.445.2017.11.20.01.25.29 for (version=TLS1 cipher=AES128-SHA bits=128/128); Mon, 20 Nov 2017 01:25:29 -0800 (PST) Date: Mon, 20 Nov 2017 10:25:26 +0100 From: Michal Hocko Subject: Re: [PATCH 1/2] mm,vmscan: Kill global shrinker lock. Message-ID: <20171120092526.llj2q3lqbbxwn4g4@dhcp22.suse.cz> References: <1510609063-3327-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp> <20171117173521.GA21692@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171117173521.GA21692@infradead.org> Sender: owner-linux-mm@kvack.org List-ID: To: Christoph Hellwig Cc: Tetsuo Handa , Minchan Kim , Huang Ying , Mel Gorman , Vladimir Davydov , Johannes Weiner , Andrew Morton , Shakeel Butt , Greg Thelen , linux-mm@kvack.org, linux-kernel@vger.kernel.org On Fri 17-11-17 09:35:21, Christoph Hellwig wrote: > On Tue, Nov 14, 2017 at 06:37:42AM +0900, Tetsuo Handa wrote: > > Since do_shrink_slab() can reschedule, we cannot protect shrinker_list > > using one RCU section. But using atomic_inc()/atomic_dec() for each > > do_shrink_slab() call will not impact so much. > > But you could use SRCU.. Davidlohr has tried that already http://lkml.kernel.org/r/1434398602.1903.15.camel@stgolabs.net and failed. Doing SRCU inside core kernel is not seen with a great support... -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org