diff options
| author | Mel Gorman <mgorman@techsingularity.net> | 2015-11-06 16:28:12 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-11-06 17:50:42 -0800 |
| commit | c9ab0c4fbeb0202bac3548378a977e1536ebe3ca (patch) | |
| tree | 44d92e1b08afbb47e64ec55d9ceb7704b4f0815c /mm | |
| parent | e2b19197ff9dc46f3e3888f273c4395f9e5a9856 (diff) | |
mm, page_alloc: remove unnecessary recalculations for dirty zone balancing
File-backed pages that will be immediately written are balanced between
zones. This heuristic tries to avoid having a single zone filled with
recently dirtied pages but the checks are unnecessarily expensive. Move
consider_zone_balanced into the alloc_context instead of checking bitmaps
multiple times. The patch also gives the parameter a more meaningful
name.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Vitaly Wool <vitalywool@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/internal.h | 1 | ||||
| -rw-r--r-- | mm/page_alloc.c | 11 |
2 files changed, 8 insertions, 4 deletions
diff --git a/mm/internal.h b/mm/internal.h index d4b807d6c963..ff0f1ada0f67 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -129,6 +129,7 @@ struct alloc_context { int classzone_idx; int migratetype; enum zone_type high_zoneidx; + bool spread_dirty_pages; }; /* diff --git a/mm/page_alloc.c b/mm/page_alloc.c index d73c346d91b3..67390988881a 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2478,8 +2478,6 @@ get_page_from_freelist(gfp_t gfp_mask, unsigned int order, int alloc_flags, nodemask_t *allowednodes = NULL;/* zonelist_cache approximation */ int zlc_active = 0; /* set if using zonelist_cache */ int did_zlc_setup = 0; /* just call zlc_setup() one time */ - bool consider_zone_dirty = (alloc_flags & ALLOC_WMARK_LOW) && - (gfp_mask & __GFP_WRITE); int nr_fair_skipped = 0; bool zonelist_rescan; @@ -2534,14 +2532,14 @@ zonelist_scan: * * XXX: For now, allow allocations to potentially * exceed the per-zone dirty limit in the slowpath - * (ALLOC_WMARK_LOW unset) before going into reclaim, + * (spread_dirty_pages unset) before going into reclaim, * which is important when on a NUMA setup the allowed * zones are together not big enough to reach the * global limit. The proper fix for these situations * will require awareness of zones in the * dirty-throttling and the flusher threads. */ - if (consider_zone_dirty && !zone_dirty_ok(zone)) + if (ac->spread_dirty_pages && !zone_dirty_ok(zone)) continue; mark = zone->watermark[alloc_flags & ALLOC_WMARK_MASK]; @@ -3232,6 +3230,10 @@ retry_cpuset: /* We set it here, as __alloc_pages_slowpath might have changed it */ ac.zonelist = zonelist; + + /* Dirty zone balancing only done in the fast path */ + ac.spread_dirty_pages = (gfp_mask & __GFP_WRITE); + /* The preferred zone is used for statistics later */ preferred_zoneref = first_zones_zonelist(ac.zonelist, ac.high_zoneidx, ac.nodemask ? : &cpuset_current_mems_allowed, @@ -3250,6 +3252,7 @@ retry_cpuset: * complete. */ alloc_mask = memalloc_noio_flags(gfp_mask); + ac.spread_dirty_pages = false; page = __alloc_pages_slowpath(alloc_mask, order, &ac); } |