From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752860AbbJOKcj (ORCPT ); Thu, 15 Oct 2015 06:32:39 -0400 Received: from mail-pa0-f49.google.com ([209.85.220.49]:33869 "EHLO mail-pa0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752624AbbJOKch (ORCPT ); Thu, 15 Oct 2015 06:32:37 -0400 Date: Thu, 15 Oct 2015 19:35:27 +0900 From: Minchan Kim To: Sergey Senozhatsky Cc: Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Sergey Senozhatsky Subject: Re: [PATCH] zsmalloc: don't test shrinker_enabled in zs_shrinker_count() Message-ID: <20151015103454.GA3527@bbox> References: <1444787879-5428-1-git-send-email-sergey.senozhatsky@gmail.com> <20151015022928.GB2840@bbox> <20151015035317.GF1735@swordfish> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20151015035317.GF1735@swordfish> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 15, 2015 at 12:53:17PM +0900, Sergey Senozhatsky wrote: > On (10/15/15 11:29), Minchan Kim wrote: > [..] > > I'm in favor of removing shrinker disable feature with this patch( > > although we didn't implement it yet) because if there is some problem > > of compaction, we should reveal and fix it without hiding with the > > feature. > > > > sure. > > > One thing I want is if we decide it, let's remove all things > > about shrinker_enabled(ie, variable). > > If we might need it later, we could introduce it easily. > > well, do we really want to make the shrinker a vital part of zsmalloc? > > it's not that we will tighten the dependency between zsmalloc and > shrinker, we will introduce it instead. in a sense that, at the moment, > zsmalloc is, let's say, ignorant to shrinker registration errors > (shrinker registration implementation is internal to shrinker), because > there is no direct impact on zsmalloc functionality -- zsmalloc will not > be able to release some pages (there are if-s here: first, zsmalloc > shrinker callback may even not be called; second, zsmalloc may not be > albe to migrate objects and release objects). > > no really strong opinion against, but at the same time zsmalloc will > have another point of failure (again, zsmalloc should not be aware of > shrinker registration implementation and why it may fail). > > so... I can prepare a new patch later today. I misunderstood your description. I thought you wanted to remove codes for disabling auto-compaction by user because I really don't want it like same reason of VM's compaction. My bad. You woke up my brain, I remember the reason. Thanks. Acked-by: Minchan Kim