From mboxrd@z Thu Jan 1 00:00:00 1970 From: Johannes Weiner Subject: Re: [RFC 01/22] Generic show_mem() implementation Date: Fri, 04 Apr 2008 00:33:42 +0200 Message-ID: <87prt6muux.fsf@saeurebad.de> References: <12071688283927-git-send-email-hannes@saeurebad.de> <1207168839586-git-send-email-hannes@saeurebad.de> <20080403075545.GC4125@osiris.boeblingen.de.ibm.com> <20080403124820.GA30356@uranus.ravnborg.org> <871w5nouwp.fsf@saeurebad.de> <20080403181202.GA32319@uranus.ravnborg.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: In-Reply-To: <20080403181202.GA32319@uranus.ravnborg.org> (Sam Ravnborg's message of "Thu, 3 Apr 2008 20:12:02 +0200") Sender: linux-kernel-owner@vger.kernel.org To: Sam Ravnborg Cc: Heiko Carstens , linux-kernel@vger.kernel.org, linux-mm@kvack.org, mingo@elte.hu, davem@davemloft.net, hskinnemoen@atmel.com, cooloney@kernel.org, starvik@axis.com, dhowells@redhat.com, ysato@users.sf.net, takata@linux-m32r.org, geert@linux-m68k.org, ralf@linux-mips.org, kyle@parisc-linux.org, paulus@samba.org, schwidefsky@de.ibm.com, lethal@linux-sh.org, jdike@addtoit.com, miles@gnu.org, chris@zankel.net, rmk@arm.linux.org.uk, tony.luck@intel.com List-Id: linux-mm.kvack.org Hi, Sam Ravnborg writes: > On Thu, Apr 03, 2008 at 04:49:42PM +0200, Johannes Weiner wrote: >> Hi, >> >> Sam Ravnborg writes: >> >> >> e.g. we currently have this in arch/s390/Kconfig: >> >> >> >> config S390 >> >> def_bool y >> >> select HAVE_OPROFILE >> >> select HAVE_KPROBES >> >> select HAVE_KRETPROBES >> >> >> >> just add a select HAVE_GENERIC_SHOWMEM or something like that in the arch >> >> specific patches. >> > Seconded. >> > See Documentation/kbuild/kconfig-language.txt for a few more hints >> > how to do it. >> >> After more thinking about it, wouldn't it be better to have >> HAVE_ARCH_SHOW_MEM in mm/Kconfig and let archs with their own show_mem() >> select it? Because there are far more archs that use the generic >> version than those having their own. > > Positive logic is almost always simpler to grasp. > And the usual way to do this is to let arch's select what they > use. > We do not want to have a situation where in most cases we select > a generic version but in some oddball case we select to have > a local version. I can not follow you. Of course the arch selects what they use. But they should not _all_ have to be flagged with an extra select. So what default-value are you arguing for? Hannes