From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f200.google.com (mail-pf0-f200.google.com [209.85.192.200]) by kanga.kvack.org (Postfix) with ESMTP id A15106B0069 for ; Tue, 10 Jan 2017 18:56:54 -0500 (EST) Received: by mail-pf0-f200.google.com with SMTP id f144so234150267pfa.3 for ; Tue, 10 Jan 2017 15:56:54 -0800 (PST) Received: from lgeamrelo13.lge.com (LGEAMRELO13.lge.com. [156.147.23.53]) by mx.google.com with ESMTP id r7si3698692pgf.303.2017.01.10.15.56.53 for ; Tue, 10 Jan 2017 15:56:53 -0800 (PST) Date: Wed, 11 Jan 2017 08:56:51 +0900 From: Minchan Kim Subject: Re: [RFC PATCH 2/2] mm, vmscan: cleanup inactive_list_is_low Message-ID: <20170110235651.GB7130@bbox> References: <20170110125552.4170-1-mhocko@kernel.org> <20170110125552.4170-3-mhocko@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170110125552.4170-3-mhocko@kernel.org> Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: linux-mm@kvack.org, Johannes Weiner , Mel Gorman , Andrew Morton , Michal Hocko Hi Michal, On Tue, Jan 10, 2017 at 01:55:52PM +0100, Michal Hocko wrote: > From: Michal Hocko > > inactive_list_is_low is duplicating logic implemented by > lruvec_lru_size_eligibe_zones. Let's use the dedicated function to get > the number of eligible pages on the lru list and ask use lruvec_lru_size > to get the total LRU lize only when the tracing is really requested. We > are still iterating over all LRUs two times in that case but a) > inactive_list_is_low is not a hot path and b) this can be addressed at > the tracing layer and only evaluate arguments only when the tracing is > enabled in future if that ever matters. Make sense so I was about to add my acked-by but surprised when I found "bool trace variable" and lruvec_lru_size in the trace so I ask some questions to the "+ mm-vmscan-add-mm_vmscan_inactive_list_is_low-tracepoint" thread. Except that part, looks good to me. > > Signed-off-by: Michal Hocko > --- > mm/vmscan.c | 38 ++++++++++---------------------------- > 1 file changed, 10 insertions(+), 28 deletions(-) > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index 137bc85067d3..a9c881f06c0e 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -2054,11 +2054,10 @@ static bool inactive_list_is_low(struct lruvec *lruvec, bool file, > struct scan_control *sc, bool trace) > { > unsigned long inactive_ratio; > - unsigned long total_inactive, inactive; > - unsigned long total_active, active; > + unsigned long inactive, active; > + enum lru_list inactive_lru = file * LRU_FILE; > + enum lru_list active_lru = file * LRU_FILE + LRU_ACTIVE; > unsigned long gb; > - struct pglist_data *pgdat = lruvec_pgdat(lruvec); > - int zid; > > /* > * If we don't have swap space, anonymous page deactivation > @@ -2067,27 +2066,8 @@ static bool inactive_list_is_low(struct lruvec *lruvec, bool file, > if (!file && !total_swap_pages) > return false; > > - total_inactive = inactive = lruvec_lru_size(lruvec, file * LRU_FILE); > - total_active = active = lruvec_lru_size(lruvec, file * LRU_FILE + LRU_ACTIVE); > - > - /* > - * For zone-constrained allocations, it is necessary to check if > - * deactivations are required for lowmem to be reclaimed. This > - * calculates the inactive/active pages available in eligible zones. > - */ > - for (zid = sc->reclaim_idx + 1; zid < MAX_NR_ZONES; zid++) { > - struct zone *zone = &pgdat->node_zones[zid]; > - unsigned long inactive_zone, active_zone; > - > - if (!managed_zone(zone)) > - continue; > - > - inactive_zone = lruvec_zone_lru_size(lruvec, file * LRU_FILE, zid); > - active_zone = lruvec_zone_lru_size(lruvec, (file * LRU_FILE) + LRU_ACTIVE, zid); > - > - inactive -= min(inactive, inactive_zone); > - active -= min(active, active_zone); > - } > + inactive = lruvec_lru_size_eligibe_zones(lruvec, inactive_lru, sc->reclaim_idx); > + active = lruvec_lru_size_eligibe_zones(lruvec, active_lru, sc->reclaim_idx); > > gb = (inactive + active) >> (30 - PAGE_SHIFT); > if (gb) > @@ -2096,10 +2076,12 @@ static bool inactive_list_is_low(struct lruvec *lruvec, bool file, > inactive_ratio = 1; > > if (trace) > - trace_mm_vmscan_inactive_list_is_low(pgdat->node_id, > + trace_mm_vmscan_inactive_list_is_low(lruvec_pgdat(lruvec)->node_id, > sc->reclaim_idx, > - total_inactive, inactive, > - total_active, active, inactive_ratio, file); > + lruvec_lru_size(lruvec, inactive_lru), inactive, > + lruvec_lru_size(lruvec, active_lru), active, > + inactive_ratio, file); > + > return inactive * inactive_ratio < active; > } > > -- > 2.11.0 > > -- > 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 -- 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