Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1031104AbbD1Nll (ORCPT ); Tue, 28 Apr 2015 09:41:41 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:50859 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965640AbbD1Nlg (ORCPT ); Tue, 28 Apr 2015 09:41:36 -0400 Date: Tue, 28 Apr 2015 06:48:10 -0700 From: Andrew Morton To: Mel Gorman Cc: Linux-MM , Nathan Zimmer , Dave Hansen , Waiman Long , Scott Norton , Daniel J Blueman , LKML Subject: Re: [PATCH 07/13] mm: meminit: Initialise a subset of struct pages if CONFIG_DEFERRED_STRUCT_PAGE_INIT is set Message-Id: <20150428064810.0882ad36.akpm@linux-foundation.org> In-Reply-To: <20150428095323.GK2449@suse.de> References: <1429785196-7668-1-git-send-email-mgorman@suse.de> <1429785196-7668-8-git-send-email-mgorman@suse.de> <20150427154344.421fd9f151bf27d365d02fd2@linux-foundation.org> <20150428095323.GK2449@suse.de> X-Mailer: Sylpheed 2.7.1 (GTK+ 2.18.9; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1469 Lines: 41 On Tue, 28 Apr 2015 10:53:23 +0100 Mel Gorman wrote: > > > +#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT > > > +#define __defermem_init __meminit > > > +#define __defer_init __meminit > > > +#else > > > +#define __defermem_init > > > +#define __defer_init __init > > > +#endif > > > > Could we get some comments describing these? What they do, when and > > where they should be used. I have a suspicion that the naming isn't > > good, but I didn't spend a lot of time reverse-engineering the > > intent... > > > > Of course. The next version will have > > +/* > + * Deferred struct page initialisation requires some early init functions that > + * are removed before kswapd is up and running. The feature depends on memory > + * hotplug so put the data and code required by deferred initialisation into > + * the __meminit section where they are preserved. > + */ I'm still not getting it even a little bit :( You say "data and code", so I'd expect to see #define __defer_meminitdata __meminitdata #define __defer_meminit __meminit But the patch doesn't mention the data segment at all. The patch uses both __defermem_init and __defer_init to tag functions (ie: text) and I can't work out why. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/