From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ee0-f48.google.com (mail-ee0-f48.google.com [74.125.83.48]) by kanga.kvack.org (Postfix) with ESMTP id 3CFD06B0031 for ; Thu, 9 Jan 2014 04:02:14 -0500 (EST) Received: by mail-ee0-f48.google.com with SMTP id e49so1155200eek.21 for ; Thu, 09 Jan 2014 01:02:13 -0800 (PST) Received: from mx2.suse.de (cantor2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id 5si2504600eei.228.2014.01.09.01.02.10 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Thu, 09 Jan 2014 01:02:12 -0800 (PST) Date: Thu, 9 Jan 2014 10:02:08 +0100 From: Michal Hocko Subject: Re: [RFC] mm: show message when updating min_free_kbytes in thp Message-ID: <20140109090208.GA27538@dhcp22.suse.cz> References: <20140101002935.GA15683@localhost.localdomain> <52C5AA61.8060701@intel.com> <20140103033303.GB4106@localhost.localdomain> <52C6FED2.7070700@intel.com> <20140105003501.GC4106@localhost.localdomain> <20140106164604.GC27602@dhcp22.suse.cz> <20140108101611.GD27937@dhcp22.suse.cz> <20140109073259.GK4106@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140109073259.GK4106@localhost.localdomain> Sender: owner-linux-mm@kvack.org List-ID: To: linux-kernel@vger.kernel.org, Mel Gorman , Andrew Morton , linux-mm@kvack.org, Dave Hansen , David Rientjes On Thu 09-01-14 15:32:59, Han Pingtian wrote: [...] > From b8db4f157a17d6d8652cc9cff024a192c3ee0779 Mon Sep 17 00:00:00 2001 > From: Han Pingtian > Date: Thu, 9 Jan 2014 15:24:26 +0800 > Subject: [PATCH] mm: show message when raising min_free_kbytes in THP > > min_free_kbytes may be raised during THP's initialization. Sometimes, > this will change the value being set by user. Showing message will > clarify this confusion. > > Only show this message when changing the value set by user according to > Michal Hocko's suggestion. > > Showing the old value of min_free_kbytes according to Dave Hansen's > suggestion. This will give user the chance to restore old value of > min_free_kbytes. > > Signed-off-by: Han Pingtian Looks good to me Reviewed-by: Michal Hocko Thanks! > --- > mm/huge_memory.c | 9 ++++++++- > mm/page_alloc.c | 2 +- > 2 files changed, 9 insertions(+), 2 deletions(-) > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index 7de1bf8..e0e4e29 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -100,6 +100,7 @@ static struct khugepaged_scan khugepaged_scan = { > .mm_head = LIST_HEAD_INIT(khugepaged_scan.mm_head), > }; > > +extern int user_min_free_kbytes; > > static int set_recommended_min_free_kbytes(void) > { > @@ -130,8 +131,14 @@ static int set_recommended_min_free_kbytes(void) > (unsigned long) nr_free_buffer_pages() / 20); > recommended_min <<= (PAGE_SHIFT-10); > > - if (recommended_min > min_free_kbytes) > + if (recommended_min > min_free_kbytes) { > + if (user_min_free_kbytes >= 0) > + pr_info("raising min_free_kbytes from %d to %lu " > + "to help transparent hugepage allocations\n", > + min_free_kbytes, recommended_min); > + > min_free_kbytes = recommended_min; > + } > setup_per_zone_wmarks(); > return 0; > } > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 9ea62b2..a9dcfd8 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -205,7 +205,7 @@ static char * const zone_names[MAX_NR_ZONES] = { > }; > > int min_free_kbytes = 1024; > -int user_min_free_kbytes; > +int user_min_free_kbytes = -1; > > static unsigned long __meminitdata nr_kernel_pages; > static unsigned long __meminitdata nr_all_pages; > -- > 1.7.7.6 > -- Michal Hocko SUSE Labs -- 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