From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753761Ab1HKUdR (ORCPT ); Thu, 11 Aug 2011 16:33:17 -0400 Received: from mx1.redhat.com ([209.132.183.28]:25466 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752608Ab1HKUdK (ORCPT ); Thu, 11 Aug 2011 16:33:10 -0400 From: Johannes Weiner To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, KAMEZAWA Hiroyuki , Michal Hocko , Ying Han , Balbir Singh , KOSAKI Motohiro , Daisuke Nishimura , Mel Gorman Subject: [patch 2/2] mm: vmscan: drop nr_force_scan[] from get_scan_count Date: Thu, 11 Aug 2011 22:31:55 +0200 Message-Id: <1313094715-31187-2-git-send-email-jweiner@redhat.com> In-Reply-To: <1313094715-31187-1-git-send-email-jweiner@redhat.com> References: <1313094715-31187-1-git-send-email-jweiner@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The nr_force_scan[] tuple holds the effective scan numbers for anon and file pages in case the situation called for a forced scan and the regularly calculated scan numbers turned out zero. However, the effective scan number can always be assumed to be SWAP_CLUSTER_MAX right before the division into anon and file. The numerators and denominator are properly set up for all cases, be it force scan for just file, just anon, or both, to do the right thing. Signed-off-by: Johannes Weiner Cc: KAMEZAWA Hiroyuki Cc: Michal Hocko Cc: Ying Han Cc: Balbir Singh Cc: KOSAKI Motohiro Cc: Daisuke Nishimura Cc: Mel Gorman --- mm/vmscan.c | 24 ++---------------------- 1 files changed, 2 insertions(+), 22 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 96061d7..45f0986 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1831,7 +1831,6 @@ static void get_scan_count(struct zone *zone, struct scan_control *sc, enum lru_list l; int noswap = 0; bool force_scan = false; - unsigned long nr_force_scan[2]; /* kswapd does zone balancing and need to scan this zone */ if (scanning_global_lru(sc) && current_is_kswapd()) @@ -1846,8 +1845,6 @@ static void get_scan_count(struct zone *zone, struct scan_control *sc, fraction[0] = 0; fraction[1] = 1; denominator = 1; - nr_force_scan[0] = 0; - nr_force_scan[1] = SWAP_CLUSTER_MAX; goto out; } @@ -1864,8 +1861,6 @@ static void get_scan_count(struct zone *zone, struct scan_control *sc, fraction[0] = 1; fraction[1] = 0; denominator = 1; - nr_force_scan[0] = SWAP_CLUSTER_MAX; - nr_force_scan[1] = 0; goto out; } } @@ -1914,11 +1909,6 @@ static void get_scan_count(struct zone *zone, struct scan_control *sc, fraction[0] = ap; fraction[1] = fp; denominator = ap + fp + 1; - if (force_scan) { - unsigned long scan = SWAP_CLUSTER_MAX; - nr_force_scan[0] = div64_u64(scan * ap, denominator); - nr_force_scan[1] = div64_u64(scan * fp, denominator); - } out: for_each_evictable_lru(l) { int file = is_file_lru(l); @@ -1927,20 +1917,10 @@ out: scan = zone_nr_lru_pages(zone, sc, l); if (priority || noswap) { scan >>= priority; + if (!scan && force_scan) + scan = SWAP_CLUSTER_MAX; scan = div64_u64(scan * fraction[file], denominator); } - - /* - * If zone is small or memcg is small, nr[l] can be 0. - * This results no-scan on this priority and priority drop down. - * For global direct reclaim, it can visit next zone and tend - * not to have problems. For global kswapd, it's for zone - * balancing and it need to scan a small amounts. When using - * memcg, priority drop can cause big latency. So, it's better - * to scan small amount. See may_noscan above. - */ - if (!scan && force_scan) - scan = nr_force_scan[file]; nr[l] = scan; } } -- 1.7.6