writeback: do not sleep on the congestion queue if there are no congested BDIs or...

[linux.git] / include / linux / mmzone.h

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index c3c17fb675eedb1e5c7ca5c10c697a7e40c8e797..39c24ebe9cfd4e75b8841deec06aa6d78c91c2ad 100644 (file)
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -423,6 +423,9 @@ struct zone {
 typedef enum {
        ZONE_RECLAIM_LOCKED,            /* prevents concurrent reclaim */
        ZONE_OOM_LOCKED,                /* zone is in OOM killer zonelist */
+       ZONE_CONGESTED,                 /* zone has many dirty pages backed by
+                                        * a congested BDI
+                                        */
 } zone_flags_t;
 
 static inline void zone_set_flag(struct zone *zone, zone_flags_t flag)
@@ -440,6 +443,11 @@ static inline void zone_clear_flag(struct zone *zone, zone_flags_t flag)
        clear_bit(flag, &zone->flags);
 }
 
+static inline int zone_is_reclaim_congested(const struct zone *zone)
+{
+       return test_bit(ZONE_CONGESTED, &zone->flags);
+}
+
 static inline int zone_is_reclaim_locked(const struct zone *zone)
 {
        return test_bit(ZONE_RECLAIM_LOCKED, &zone->flags);