From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BC7BFC004D4 for ; Thu, 19 Jan 2023 08:43:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229944AbjASInH (ORCPT ); Thu, 19 Jan 2023 03:43:07 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53324 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229704AbjASInC (ORCPT ); Thu, 19 Jan 2023 03:43:02 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 833835B477 for ; Thu, 19 Jan 2023 00:42:59 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 2073D612BF for ; Thu, 19 Jan 2023 08:42:59 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 16584C433EF; Thu, 19 Jan 2023 08:42:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1674117778; bh=LI6M/IodIDraG4vo0tg2WqsUpGHdn0SKKJzyG9vr+tw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=VOuixRcRgj/7x446d+Ap8L7MWaHxeIl0r71eppXqqUevWV8MuS9Rw0+bF0RX5+Qlx h57Wfn5V3LeXtpdhrJCWJCDYWjJJgghC7Rr5MKg60Lx/2mQRi0bpkBhuPkReUDOunw 2ve8jGS6OjKFanEUZ+yPzmdeVzKStoF6J4AVrn0y3nVzQvNpeG0p9wSxZTjneczSMa 6I4IByf3wUv0DPoo+GtGHMLSDq+xR1yhlTmmLxRnLv4Xp8595wcxneK+w7S7OuUeKs fZQpZrVs2tqaw8o2KVougEhYtEWmTDD2Z/AWKdSTN1tMYec0cZdt9eEH+tA/WEYdef MSVlshASIw6ew== Date: Thu, 19 Jan 2023 10:42:45 +0200 From: Mike Rapoport To: Pasha Tatashin Cc: akpm@linux-foundation.org, mhocko@suse.com, vbabka@suse.cz, david@redhat.com, quic_charante@quicinc.com, lizhe.67@bytedance.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v2] mm/page_ext: init page_ext early if there are no deferred struct pages Message-ID: References: <20230118155251.2522985-1-pasha.tatashin@soleen.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230118155251.2522985-1-pasha.tatashin@soleen.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 18, 2023 at 03:52:51PM +0000, Pasha Tatashin wrote: > page_ext must be initialized after all struct pages are initialized. > Therefore, page_ext is initialized after page_alloc_init_late(), and > can optionally be initialized earlier via early_page_ext kernel > parameter which as a side effect also disables deferred struct pages. > > Allow to automatically init page_ext early when there are no deferred > struct pages in order to be able to use page_ext during kernel boot > and track for example page allocations early. > > Signed-off-by: Pasha Tatashin Acked-by: Mike Rapoport (IBM) > --- > include/linux/page_ext.h | 2 ++ > init/main.c | 6 +++--- > mm/page_alloc.c | 6 +++++- > mm/page_ext.c | 2 +- > 4 files changed, 11 insertions(+), 5 deletions(-) > > Changelog: > v2: Fixed build issue with CONFIG_PAGE_EXTENSION=n > > diff --git a/include/linux/page_ext.h b/include/linux/page_ext.h > index 67314f648aeb..bc2e39090a1f 100644 > --- a/include/linux/page_ext.h > +++ b/include/linux/page_ext.h > @@ -29,6 +29,8 @@ struct page_ext_operations { > bool need_shared_flags; > }; > > +extern bool deferred_struct_pages; > + > #ifdef CONFIG_PAGE_EXTENSION > > /* > diff --git a/init/main.c b/init/main.c > index e1c3911d7c70..64cd2ff051c4 100644 > --- a/init/main.c > +++ b/init/main.c > @@ -855,8 +855,8 @@ static void __init mm_init(void) > pgtable_init(); > debug_objects_mem_init(); > vmalloc_init(); > - /* Should be run after vmap initialization */ > - if (early_page_ext_enabled()) > + /* If no deferred init page_ext now, as vmap is fully initialized */ > + if (!deferred_struct_pages) > page_ext_init(); > /* Should be run before the first non-init thread is created */ > init_espfix_bsp(); > @@ -1628,7 +1628,7 @@ static noinline void __init kernel_init_freeable(void) > padata_init(); > page_alloc_init_late(); > /* Initialize page ext after all struct pages are initialized. */ > - if (!early_page_ext_enabled()) > + if (deferred_struct_pages) > page_ext_init(); > > do_basic_setup(); > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 99ebb08dc3f2..717f12e83b85 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -430,6 +430,8 @@ EXPORT_SYMBOL(nr_online_nodes); > > int page_group_by_mobility_disabled __read_mostly; > > +bool deferred_struct_pages __meminitdata; > + > #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT > /* > * During boot we initialize deferred pages on-demand, as needed, but once > @@ -6803,8 +6805,10 @@ void __meminit memmap_init_range(unsigned long size, int nid, unsigned long zone > if (context == MEMINIT_EARLY) { > if (overlap_memmap_init(zone, &pfn)) > continue; > - if (defer_init(nid, pfn, zone_end_pfn)) > + if (defer_init(nid, pfn, zone_end_pfn)) { > + deferred_struct_pages = true; > break; > + } > } > > page = pfn_to_page(pfn); > diff --git a/mm/page_ext.c b/mm/page_ext.c > index e2c22ffdbb81..dc1626be458b 100644 > --- a/mm/page_ext.c > +++ b/mm/page_ext.c > @@ -92,7 +92,7 @@ unsigned long page_ext_size; > static unsigned long total_usage; > static struct page_ext *lookup_page_ext(const struct page *page); > > -bool early_page_ext; > +bool early_page_ext __meminitdata; > static int __init setup_early_page_ext(char *str) > { > early_page_ext = true; > -- > 2.39.0.314.g84b9a713c41-goog > -- Sincerely yours, Mike.