drm/bridge: dw_hdmi: clear ih_mute register when system resume

[firefly-linux-kernel-4.4.55.git] / mm / zsmalloc.c

diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index 9f15bdd9163c2360edf2e070023b6099b683a85c..c1ea19478119f21afa1a3a2d27537c251f6c152d 100644 (file)
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -309,7 +309,12 @@ static void free_handle(struct zs_pool *pool, unsigned long handle)
 
 static void record_obj(unsigned long handle, unsigned long obj)
 {
-       *(unsigned long *)handle = obj;
+       /*
+        * lsb of @obj represents handle lock while other bits
+        * represent object value the handle is pointing so
+        * updating shouldn't do store tearing.
+        */
+       WRITE_ONCE(*(unsigned long *)handle, obj);
 }
 
 /* zpool driver */
@@ -1635,6 +1640,13 @@ static int migrate_zspage(struct zs_pool *pool, struct size_class *class,
                free_obj = obj_malloc(d_page, class, handle);
                zs_object_copy(free_obj, used_obj, class);
                index++;
+               /*
+                * record_obj updates handle's value to free_obj and it will
+                * invalidate lock bit(ie, HANDLE_PIN_BIT) of handle, which
+                * breaks synchronization using pin_tag(e,g, zs_free) so
+                * let's keep the lock bit.
+                */
+               free_obj |= BIT(HANDLE_PIN_BIT);
                record_obj(handle, free_obj);
                unpin_tag(handle);
                obj_free(pool, class, used_obj);
@@ -1720,10 +1732,13 @@ static struct page *isolate_source_page(struct size_class *class)
 static unsigned long zs_can_compact(struct size_class *class)
 {
        unsigned long obj_wasted;
+       unsigned long obj_allocated = zs_stat_get(class, OBJ_ALLOCATED);
+       unsigned long obj_used = zs_stat_get(class, OBJ_USED);
 
-       obj_wasted = zs_stat_get(class, OBJ_ALLOCATED) -
-               zs_stat_get(class, OBJ_USED);
+       if (obj_allocated <= obj_used)
+               return 0;
 
+       obj_wasted = obj_allocated - obj_used;
        obj_wasted /= get_maxobj_per_zspage(class->size,
                        class->pages_per_zspage);