From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with ESMTP id 6A0906B003D for ; Tue, 10 Feb 2009 11:21:32 -0500 (EST) Date: Tue, 10 Feb 2009 17:20:52 +0100 From: Johannes Weiner Subject: Re: [PATCH] shrink_all_memory() use sc.nr_reclaimed Message-ID: <20090210162052.GB2371@cmpxchg.org> References: <28c262360902100440v765d3f7bnd56cc4b5510349c0@mail.gmail.com> <20090210215718.700D.KOSAKI.MOTOHIRO@jp.fujitsu.com> <20090210215811.7010.KOSAKI.MOTOHIRO@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090210215811.7010.KOSAKI.MOTOHIRO@jp.fujitsu.com> Sender: owner-linux-mm@kvack.org To: KOSAKI Motohiro Cc: MinChan Kim , Rik van Riel , "Rafael J. Wysocki" , William Lee Irwin III , Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On Tue, Feb 10, 2009 at 10:00:26PM +0900, KOSAKI Motohiro wrote: > Impact: cleanup > > Commit a79311c14eae4bb946a97af25f3e1b17d625985d "vmscan: bail out of > direct reclaim after swap_cluster_max pages" moved the nr_reclaimed > counter into the scan control to accumulate the number of all > reclaimed pages in a reclaim invocation. > > shrink_all_memory() can use the same mechanism. it increase code > consistency. > > > Signed-off-by: KOSAKI Motohiro > Cc: MinChan Kim > Cc: Johannes Weiner > Cc: "Rafael J. Wysocki" > Cc: Rik van Riel > --- > mm/vmscan.c | 49 ++++++++++++++++++++++++------------------------- > 1 file changed, 24 insertions(+), 25 deletions(-) > > Index: b/mm/vmscan.c > =================================================================== > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -2004,16 +2004,15 @@ unsigned long global_lru_pages(void) > #ifdef CONFIG_PM > /* > * Helper function for shrink_all_memory(). Tries to reclaim 'nr_pages' pages > - * from LRU lists system-wide, for given pass and priority, and returns the > - * number of reclaimed pages > + * from LRU lists system-wide, for given pass and priority. > * > * For pass > 3 we also try to shrink the LRU lists that contain a few pages > */ > -static unsigned long shrink_all_zones(unsigned long nr_pages, int prio, > +static void shrink_all_zones(unsigned long nr_pages, int prio, > int pass, struct scan_control *sc) > { > struct zone *zone; > - unsigned long nr_to_scan, ret = 0; > + unsigned long nr_to_scan; > enum lru_list l; Basing it on swsusp-clean-up-shrink_all_zones.patch probably makes it easier for Andrew to pick it up. > for_each_zone(zone) { > @@ -2038,15 +2037,13 @@ static unsigned long shrink_all_zones(un > nr_to_scan = min(nr_pages, > zone_page_state(zone, > NR_LRU_BASE + l)); > - ret += shrink_list(l, nr_to_scan, zone, > - sc, prio); > - if (ret >= nr_pages) > - return ret; > + sc->nr_reclaimed += shrink_list(l, nr_to_scan, > + zone, sc, prio); > + if (sc->nr_reclaimed >= nr_pages) > + return; > } > } > } > - > - return ret; > } > > /* > @@ -2060,10 +2057,10 @@ static unsigned long shrink_all_zones(un > unsigned long shrink_all_memory(unsigned long nr_pages) > { > unsigned long lru_pages, nr_slab; > - unsigned long ret = 0; > int pass; > struct reclaim_state reclaim_state; > struct scan_control sc = { > + .nr_reclaimed = 0, > .gfp_mask = GFP_KERNEL, > .may_swap = 0, > .swap_cluster_max = nr_pages, > @@ -2083,8 +2080,8 @@ unsigned long shrink_all_memory(unsigned > if (!reclaim_state.reclaimed_slab) > break; > > - ret += reclaim_state.reclaimed_slab; > - if (ret >= nr_pages) > + sc.nr_reclaimed += reclaim_state.reclaimed_slab; > + if (sc.nr_reclaimed >= nr_pages) > goto out; > > nr_slab -= reclaim_state.reclaimed_slab; > @@ -2108,18 +2105,18 @@ unsigned long shrink_all_memory(unsigned > } > > for (prio = DEF_PRIORITY; prio >= 0; prio--) { > - unsigned long nr_to_scan = nr_pages - ret; > + unsigned long nr_to_scan = nr_pages - sc.nr_reclaimed; > > sc.nr_scanned = 0; > - ret += shrink_all_zones(nr_to_scan, prio, pass, &sc); > - if (ret >= nr_pages) > + shrink_all_zones(nr_to_scan, prio, pass, &sc); > + if (sc.nr_reclaimed >= nr_pages) > goto out; > > reclaim_state.reclaimed_slab = 0; > shrink_slab(sc.nr_scanned, sc.gfp_mask, > global_lru_pages()); > - ret += reclaim_state.reclaimed_slab; > - if (ret >= nr_pages) > + sc.nr_reclaimed += reclaim_state.reclaimed_slab; > + if (sc.nr_reclaimed >= nr_pages) > goto out; > > if (sc.nr_scanned && prio < DEF_PRIORITY - 2) > @@ -2128,21 +2125,23 @@ unsigned long shrink_all_memory(unsigned > } > > /* > - * If ret = 0, we could not shrink LRUs, but there may be something > - * in slab caches > + * If sc.nr_reclaimed = 0, we could not shrink LRUs, but there may be > + * something in slab caches > */ > - if (!ret) { > + if (!sc.nr_reclaimed) { > do { > reclaim_state.reclaimed_slab = 0; > - shrink_slab(nr_pages, sc.gfp_mask, global_lru_pages()); > - ret += reclaim_state.reclaimed_slab; > - } while (ret < nr_pages && reclaim_state.reclaimed_slab > 0); > + shrink_slab(nr_pages, sc.gfp_mask, > + global_lru_pages()); > + sc.nr_reclaimed += reclaim_state.reclaimed_slab; > + } while (sc.nr_reclaimed < nr_pages && > + reclaim_state.reclaimed_slab > 0); :( Is this really an improvement? `ret' is better to read than `sc.nr_reclaimed'. Hannes -- 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