From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Hansen Subject: Re: [PATCH V2 1/2] mm: move FAULT_AROUND_ORDER to arch/ Date: Wed, 09 Apr 2014 08:46:41 -0700 Message-ID: <53456B61.1040901@intel.com> References: <1396592835-24767-1-git-send-email-maddy@linux.vnet.ibm.com> <1396592835-24767-2-git-send-email-maddy@linux.vnet.ibm.com> <533EDB63.8090909@intel.com> <5344A312.80802@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <5344A312.80802@linux.vnet.ibm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linuxppc-dev-bounces+glppe-linuxppc-embedded-2=m.gmane.org@lists.ozlabs.org Sender: "Linuxppc-dev" To: Madhavan Srinivasan , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, x86@kernel.org Cc: riel@redhat.com, ak@linux.intel.com, peterz@infradead.org, rusty@rustcorp.com.au, paulus@samba.org, mgorman@suse.de, akpm@linux-foundation.org, mingo@kernel.org, kirill.shutemov@linux.intel.com List-Id: linux-arch.vger.kernel.org T24gMDQvMDgvMjAxNCAwNjozMiBQTSwgTWFkaGF2YW4gU3Jpbml2YXNhbiB3cm90ZToKPj4gPiBJ biBtbS9LY29uZmlnLCBwdXQKPj4gPiAKPj4gPiAJY29uZmlnIEZBVUxUX0FST1VORF9PUkRFUgo+ PiA+IAkJaW50Cj4+ID4gCQlkZWZhdWx0IDEyMzQgaWYgUE9XRVJQQwo+PiA+IAkJZGVmYXVsdCA0 Cj4+ID4gCj4+ID4gVGhlIHdheSB5b3UgaGF2ZSBpdCBub3csIGV2ZXJ5IHNpbmdsZSBhcmNoaXRl Y3R1cmUgdGhhdCBuZWVkcyB0byBlbmFibGUKPj4gPiB0aGlzIGhhcyB0byBnbyBwdXQgdGhhdCBp biB0aGVpciBLY29uZmlnLiAgVGhhdCdzIG1hZG5lc3MuICBUaGlzIHdheSwKPiBJIHRob3VnaCBh Ym91dCBpdCBhbmQgZGVjaWRlZCBub3QgdG8gZG8gdGhpcyB3YXkgYmVjYXVzZSwgaW4gZnV0dXJl LAo+IHN1YiBwbGF0Zm9ybXMgb2YgdGhlIGFyY2hpdGVjdHVyZSBtYXkgZGVjaWRlIHRvIGNoYW5n ZSB0aGUgdmFsdWVzLiBBbHNvLAo+IGFkZGluZyBhbiBpZiBsaW5lIGZvciBlYWNoIGFyY2hpdGVj dHVyZSB3aXRoIGRpZmZlcmVudCBzdWIgcGxhdGZvcm1zCj4gb3JpbmcgdG8gaXQgd2lsbCBsb29r IG1lc3N5LgoKSSdtIG5vdCBzdXJlIHdoeSBJJ20gdHJ5aW5nIGhlcmUgYW55IG1vcmUuICBZb3Ug ZG8gc2VlbSBxdWl0ZSBjb250ZW50IHRvCmFkZCBhcyBtdWNoIGNydWZ0IHRvIHBwYyBhbmQgZXZl cnkgb3RoZXIgYXJjaGl0ZWN0dXJlIGFzIHBvc3NpYmxlLiAgSWYKeW91ciB0aGVvcmV0aWNhbCBz Y2VuYXJpbyBwb3BzIHVwLCB5b3Ugc2ltcGx5IGRvIHRoaXMgaW4gcHBjOgoKY29uZmlnIEFSQ0hf RkFVTFRfQVJPVU5EX09SREVSCglpbnQKCWRlZmF1bHQgOTk5CglkZWZhdWx0IDg4OCBpZiBPVEhF Ul9TSUxMWV9QT1dFUlBDX1NVQkFSQ0gKCkJ1dCAqT05MWSogaW4gdGhlIGFyY2hpdGVjdHVyZXMg dGhhdCBjYXJlIGFib3V0IGRvaW5nIHRoYXQgc3R1ZmYuICBZb3UKbGVhdmUgZXZlcnkgb3RoZXIg YXJjaGl0ZWN0dXJlIG9uIHRoZSBwbGFuZXQgYWxvbmUuICBUaGVuLCBpbiBtbS9LY29uZmlnOgoK Y29uZmlnIEZBVUxUX0FST1VORF9PUkRFUgoJaW50CglkZWZhdWx0IEFSQ0hfRkFVTFRfQVJPVU5E X09SREVSIGlmIEFSQ0hfRkFVTFRfQVJPVU5EX09SREVSCglkZWZhdWx0IDQKCllvdXIgd2F5IHN0 aWxsIHJlcXVpcmVzIGdvaW5nIGFuZCBpbmRpdmlkdWFsbHkgdG91Y2hpbmcgZXZlcnkgc2luZ2xl CmFyY2hpdGVjdHVyZSdzIEtjb25maWcgdGhhdCB3YW50cyB0byBlbmFibGUgZmF1bHQgYXJvdW5k LiAgVGhhdCdzIG5vdCBhbgphY2NlcHRhYmxlIHNvbHV0aW9uLgpfX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fXwpMaW51eHBwYy1kZXYgbWFpbGluZyBsaXN0Ckxp bnV4cHBjLWRldkBsaXN0cy5vemxhYnMub3JnCmh0dHBzOi8vbGlzdHMub3psYWJzLm9yZy9saXN0 aW5mby9saW51eHBwYy1kZXY= From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga02.intel.com ([134.134.136.20]:62851 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933002AbaDIPvC (ORCPT ); Wed, 9 Apr 2014 11:51:02 -0400 Message-ID: <53456B61.1040901@intel.com> Date: Wed, 09 Apr 2014 08:46:41 -0700 From: Dave Hansen MIME-Version: 1.0 Subject: Re: [PATCH V2 1/2] mm: move FAULT_AROUND_ORDER to arch/ References: <1396592835-24767-1-git-send-email-maddy@linux.vnet.ibm.com> <1396592835-24767-2-git-send-email-maddy@linux.vnet.ibm.com> <533EDB63.8090909@intel.com> <5344A312.80802@linux.vnet.ibm.com> In-Reply-To: <5344A312.80802@linux.vnet.ibm.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-arch-owner@vger.kernel.org List-ID: To: Madhavan Srinivasan , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, x86@kernel.org Cc: benh@kernel.crashing.org, paulus@samba.org, kirill.shutemov@linux.intel.com, rusty@rustcorp.com.au, akpm@linux-foundation.org, riel@redhat.com, mgorman@suse.de, ak@linux.intel.com, peterz@infradead.org, mingo@kernel.org Message-ID: <20140409154641.Jd3qHFzyEgyngZVw8NaHlxIPIyYn5Mvp35TuRtofoSI@z> On 04/08/2014 06:32 PM, Madhavan Srinivasan wrote: >> > In mm/Kconfig, put >> > >> > config FAULT_AROUND_ORDER >> > int >> > default 1234 if POWERPC >> > default 4 >> > >> > The way you have it now, every single architecture that needs to enable >> > this has to go put that in their Kconfig. That's madness. This way, > I though about it and decided not to do this way because, in future, > sub platforms of the architecture may decide to change the values. Also, > adding an if line for each architecture with different sub platforms > oring to it will look messy. I'm not sure why I'm trying here any more. You do seem quite content to add as much cruft to ppc and every other architecture as possible. If your theoretical scenario pops up, you simply do this in ppc: config ARCH_FAULT_AROUND_ORDER int default 999 default 888 if OTHER_SILLY_POWERPC_SUBARCH But *ONLY* in the architectures that care about doing that stuff. You leave every other architecture on the planet alone. Then, in mm/Kconfig: config FAULT_AROUND_ORDER int default ARCH_FAULT_AROUND_ORDER if ARCH_FAULT_AROUND_ORDER default 4 Your way still requires going and individually touching every single architecture's Kconfig that wants to enable fault around. That's not an acceptable solution.