From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Sun, 27 Jan 2008 21:33:12 -0800 From: Andrew Morton Subject: Re: [PATCH] remove duplicating priority setting in try_to_free_p Message-Id: <20080127213312.517b8014.akpm@linux-foundation.org> In-Reply-To: <28c262360801252329q7232edc2l2d0e4ed17c054832@mail.gmail.com> References: <28c262360801252329q7232edc2l2d0e4ed17c054832@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: minchan kim Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Martin Bligh , Nick Piggin List-ID: On Sat, 26 Jan 2008 02:29:23 -0500 "minchan kim" wrote: > shrink_zones in try_to_free_pages already set zone through > note_zone_scanning_priority. > So, setting prev_priority in try_to_free_pages is needless. > > This patch is made by 2.6.24-rc8. > > Signed-off-by: barrios > --- > mm/vmscan.c | 17 ----------------- > 1 files changed, 0 insertions(+), 17 deletions(-) > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index e5a9597..fc55c23 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -1273,23 +1273,6 @@ unsigned long try_to_free_pages(struct z > if (!sc.all_unreclaimable) > ret = 1; > out: > - /* > - * Now that we've scanned all the zones at this priority level, note > - * that level within the zone so that the next thread which performs > - * scanning of this zone will immediately start out at this priority > - * level. This affects only the decision whether or not to bring > - * mapped pages onto the inactive list. > - */ > - if (priority < 0) > - priority = 0; > - for (i = 0; zones[i] != NULL; i++) { > - struct zone *zone = zones[i]; > - > - if (!cpuset_zone_allowed_hardwall(zone, GFP_KERNEL)) > - continue; > - > - zone->prev_priority = priority; > - } > return ret; > } (your mail client is replacing tabs with spaces) I think this is actually a bugfix. The code you're removing doesn't do the if (priority < zone->prev_priority) thing. otoh with this change, the only thing which will cause prev_priority to increase (ie: lower priority) is kswapd, which seems odd. So: a) this is a functional change and needs more thought and lots of runtime testing. I'll duck it for now. b) the prev_priority stuff is still screwed up. -- 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