staging: android: lowmemorykiller: Don't count reserved free memory

The amount of reserved memory varies between devices. Subtract it
here to reduce the amount of devices specific tuning needed for the
minfree values.

Cc: Android Kernel Team <kernel-team@android.com>
Cc: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/android/lowmemorykiller.c

@@ -35,6 +35,7 @@
 #include <linux/mm.h>
 #include <linux/oom.h>
 #include <linux/sched.h>
+#include <linux/swap.h>
 #include <linux/rcupdate.h>
 #include <linux/profile.h>
 #include <linux/notifier.h>
@@ -74,7 +75,7 @@ static int lowmem_shrink(struct shrinker *s, struct shrink_control *sc)
 	int selected_tasksize = 0;
 	short selected_oom_score_adj;
 	int array_size = ARRAY_SIZE(lowmem_adj);
-	int other_free = global_page_state(NR_FREE_PAGES);
+	int other_free = global_page_state(NR_FREE_PAGES) - totalreserve_pages;
 	int other_file = global_page_state(NR_FILE_PAGES) -
 						global_page_state(NR_SHMEM);