Fix 'negative objects to delete' warning

[zfs.git] / module / zfs / arc.c

diff --git a/module/zfs/arc.c b/module/zfs/arc.c
index f1f972b..eb5304a 100644 (file)
--- a/module/zfs/arc.c
+++ b/module/zfs/arc.c
@@ -2196,15 +2196,20 @@ SPL_SHRINKER_CALLBACK_PROTO(arc_shrinker_func, cb, nr_to_scan, gfp_mask)
        arc_reclaim_strategy_t strategy;
        int arc_reclaim;
 
-       /* Not allowed to perform filesystem reclaim */
-       if (!(gfp_mask & __GFP_FS))
-               return (-1);
-
        /* Return number of reclaimable pages based on arc_shrink_shift */
-       arc_reclaim = btop((arc_size - arc_c_min)) >> arc_shrink_shift;
+       arc_reclaim = MAX(btop(((int64_t)arc_size - (int64_t)arc_c_min))
+           >> arc_shrink_shift, 0);
        if (nr_to_scan == 0)
                return (arc_reclaim);
 
+       /* Prevent reclaim below arc_c_min */
+       if (arc_reclaim <= 0)
+               return (-1);
+
+       /* Not allowed to perform filesystem reclaim */
+       if (!(gfp_mask & __GFP_FS))
+               return (-1);
+
        /* Reclaim in progress */
        if (mutex_tryenter(&arc_reclaim_thr_lock) == 0)
                return (-1);
@@ -2218,7 +2223,8 @@ SPL_SHRINKER_CALLBACK_PROTO(arc_shrinker_func, cb, nr_to_scan, gfp_mask)
        }
 
        arc_kmem_reap_now(strategy);
-       arc_reclaim = btop((arc_size - arc_c_min)) >> arc_shrink_shift;
+       arc_reclaim = MAX(btop(((int64_t)arc_size - (int64_t)arc_c_min))
+           >> arc_shrink_shift, 0);
        mutex_exit(&arc_reclaim_thr_lock);
 
        return (arc_reclaim);