Allocations that do not have to respect the watermarks are rare
high-priority events.  Reorder the code such that per-zone dirty
limits and future checks important only to regular page allocations
are ignored in these extraordinary situations.

Signed-off-by: Johannes Weiner <han...@cmpxchg.org>
---
 mm/page_alloc.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index d9df57d..af1d956b 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1867,12 +1867,17 @@ zonelist_scan:
         */
        for_each_zone_zonelist_nodemask(zone, z, zonelist,
                                                high_zoneidx, nodemask) {
+               unsigned long mark;
+
                if (IS_ENABLED(CONFIG_NUMA) && zlc_active &&
                        !zlc_zone_worth_trying(zonelist, z, allowednodes))
                                continue;
                if ((alloc_flags & ALLOC_CPUSET) &&
                        !cpuset_zone_allowed_softwall(zone, gfp_mask))
                                continue;
+               BUILD_BUG_ON(ALLOC_NO_WATERMARKS < NR_WMARK);
+               if (alloc_flags & ALLOC_NO_WATERMARKS)
+                       goto try_this_zone;
                /*
                 * When allocating a page cache page for writing, we
                 * want to get it from a zone that is within its dirty
@@ -1903,16 +1908,11 @@ zonelist_scan:
                    (gfp_mask & __GFP_WRITE) && !zone_dirty_ok(zone))
                        goto this_zone_full;
 
-               BUILD_BUG_ON(ALLOC_NO_WATERMARKS < NR_WMARK);
-               if (!(alloc_flags & ALLOC_NO_WATERMARKS)) {
-                       unsigned long mark;
+               mark = zone->watermark[alloc_flags & ALLOC_WMARK_MASK];
+               if (!zone_watermark_ok(zone, order, mark,
+                                      classzone_idx, alloc_flags)) {
                        int ret;
 
-                       mark = zone->watermark[alloc_flags & ALLOC_WMARK_MASK];
-                       if (zone_watermark_ok(zone, order, mark,
-                                   classzone_idx, alloc_flags))
-                               goto try_this_zone;
-
                        if (IS_ENABLED(CONFIG_NUMA) &&
                                        !did_zlc_setup && nr_online_nodes > 1) {
                                /*
-- 
1.8.3.2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to