Direct reclaim currently calls shrink_zones() to reclaim all members of a zonelist, and if that wasn't successful it does another pass through the same zonelist to check overall reclaimability.
Just check reclaimability in shrink_zones() directly and propagate the result through the return value. Then remove all_unreclaimable(). Signed-off-by: Johannes Weiner <[email protected]> --- mm/vmscan.c | 48 +++++++++++++++++++++++------------------------- 1 file changed, 23 insertions(+), 25 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index ed1efb84c542..d0bc1a209746 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2244,9 +2244,10 @@ static inline bool should_continue_reclaim(struct zone *zone, } } -static void shrink_zone(struct zone *zone, struct scan_control *sc) +static unsigned long shrink_zone(struct zone *zone, struct scan_control *sc) { unsigned long nr_reclaimed, nr_scanned; + unsigned long zone_reclaimed = 0; do { struct mem_cgroup *root = sc->target_mem_cgroup; @@ -2290,8 +2291,12 @@ static void shrink_zone(struct zone *zone, struct scan_control *sc) sc->nr_scanned - nr_scanned, sc->nr_reclaimed - nr_reclaimed); + zone_reclaimed += sc->nr_reclaimed - nr_reclaimed; + } while (should_continue_reclaim(zone, sc->nr_reclaimed - nr_reclaimed, sc->nr_scanned - nr_scanned, sc)); + + return zone_reclaimed; } /* Returns true if compaction should go ahead for a high-order request */ @@ -2340,8 +2345,10 @@ static inline bool compaction_ready(struct zone *zone, int order) * * If a zone is deemed to be full of pinned pages then just give it a light * scan then give up on it. + * + * Returns whether the zones overall are reclaimable or not. */ -static void shrink_zones(struct zonelist *zonelist, struct scan_control *sc) +static bool shrink_zones(struct zonelist *zonelist, struct scan_control *sc) { struct zoneref *z; struct zone *zone; @@ -2354,6 +2361,7 @@ static void shrink_zones(struct zonelist *zonelist, struct scan_control *sc) .gfp_mask = sc->gfp_mask, }; enum zone_type requested_highidx = gfp_zone(sc->gfp_mask); + bool all_unreclaimable = true; /* * If the number of buffer_heads in the machine exceeds the maximum @@ -2368,6 +2376,8 @@ static void shrink_zones(struct zonelist *zonelist, struct scan_control *sc) for_each_zone_zonelist_nodemask(zone, z, zonelist, gfp_zone(sc->gfp_mask), sc->nodemask) { + unsigned long zone_reclaimed = 0; + if (!populated_zone(zone)) continue; /* @@ -2414,10 +2424,15 @@ static void shrink_zones(struct zonelist *zonelist, struct scan_control *sc) &nr_soft_scanned); sc->nr_reclaimed += nr_soft_reclaimed; sc->nr_scanned += nr_soft_scanned; + zone_reclaimed += nr_soft_reclaimed; /* need some check for avoid more shrink_zone() */ } - shrink_zone(zone, sc); + zone_reclaimed += shrink_zone(zone, sc); + + if (zone_reclaimed || + (global_reclaim(sc) && zone_reclaimable(zone))) + all_unreclaimable = false; } /* @@ -2439,26 +2454,8 @@ static void shrink_zones(struct zonelist *zonelist, struct scan_control *sc) * promoted it to __GFP_HIGHMEM. */ sc->gfp_mask = orig_mask; -} -/* All zones in zonelist are unreclaimable? */ -static bool all_unreclaimable(struct zonelist *zonelist, - struct scan_control *sc) -{ - struct zoneref *z; - struct zone *zone; - - for_each_zone_zonelist_nodemask(zone, z, zonelist, - gfp_zone(sc->gfp_mask), sc->nodemask) { - if (!populated_zone(zone)) - continue; - if (!cpuset_zone_allowed_hardwall(zone, GFP_KERNEL)) - continue; - if (zone_reclaimable(zone)) - return false; - } - - return true; + return !all_unreclaimable; } /* @@ -2482,6 +2479,7 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist, { unsigned long total_scanned = 0; unsigned long writeback_threshold; + bool zones_reclaimable; delayacct_freepages_start(); @@ -2492,7 +2490,7 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist, vmpressure_prio(sc->gfp_mask, sc->target_mem_cgroup, sc->priority); sc->nr_scanned = 0; - shrink_zones(zonelist, sc); + zones_reclaimable = shrink_zones(zonelist, sc); total_scanned += sc->nr_scanned; if (sc->nr_reclaimed >= sc->nr_to_reclaim) @@ -2533,8 +2531,8 @@ out: if (sc->compaction_ready) return 1; - /* top priority shrink_zones still had more to do? don't OOM, then */ - if (global_reclaim(sc) && !all_unreclaimable(zonelist, sc)) + /* Any of the zones still reclaimable? Don't OOM. */ + if (zones_reclaimable) return 1; return 0; -- 2.0.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
