From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx162.postini.com [74.125.245.162]) by kanga.kvack.org (Postfix) with SMTP id 0F17F6B0032 for ; Tue, 5 Feb 2013 20:44:06 -0500 (EST) Date: Wed, 6 Feb 2013 10:44:04 +0900 From: Minchan Kim Subject: Re: [PATCH] zsmalloc: Add Kconfig for enabling PTE method Message-ID: <20130206014404.GG11197@blaptop> References: <1359937421-19921-1-git-send-email-minchan@kernel.org> <20130204185146.GA31284@kroah.com> <20130205000854.GC2610@blaptop> <20130205192520.GA8441@kroah.com> <20130206011721.GE11197@blaptop> <20130206014259.GC816@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130206014259.GC816@kroah.com> Sender: owner-linux-mm@kvack.org List-ID: To: Greg Kroah-Hartman Cc: Andrew Morton , Seth Jennings , Nitin Gupta , Dan Magenheimer , Konrad Rzeszutek Wilk , linux-mm@kvack.org, linux-kernel@vger.kernel.org Hi Greg, On Tue, Feb 05, 2013 at 05:42:59PM -0800, Greg Kroah-Hartman wrote: > On Wed, Feb 06, 2013 at 10:17:21AM +0900, Minchan Kim wrote: > > > > > Did you test this? I don't see the new config value you added actually > > > > > do anything in this code. Also, if I select it incorrectly on ARM, or > > > > > > > > *slaps self* > > > > > > Ok, so I'll drop this patch now. As for what to do instead, I have no > > > idea, sorry, but the others should. > > > > Okay. Then, let's discuss further. > > The history we introuced copy-based method is due to portability casused by > > set_pte and __flush_tlb_one usage in young zsmalloc age. They are gone now > > so there isn't issue any more. But we found copy-based method is 3 times faster > > than pte-based in VM so I expect you guys don't want to give up it for just > > portability. Of course, > > I can't give up pte-based model as you know well, it's 6 times faster than > > copy-based model in ARM. > > > > Hard-coding for some arch like now isn't good and Kconfig for selecting choice > > was rejected by Greg as you can see above. > > I rejected your patch because it did not do anything, why would I accept > it? > > What would you have done in my situation? > > It's not an issue of "portability" or "speed" or anything other than > "the patch you sent was obviously not correct." I totally misunderstood that you'd like to solve this issue. "Also, if I select it incorrectly on ARM, or or other platforms, what is keeping this from doing bad things?" Then, I will resend it soon. Thanks. > > greg k-h > > -- > 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 -- Kind regards, Minchan Kim -- 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