From: Con Kolivas <kernel@kolivas.org>

Avoid entering trickle_swap() when first initialising kprefetchd to prevent
endless loops.

Signed-off-by: Con Kolivas <kernel@kolivas.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/swap_prefetch.c |    4 ++++
 1 file changed, 4 insertions(+)

diff -puN mm/swap_prefetch.c~swap-prefetch-avoid-repeating-entry mm/swap_prefetch.c
--- a/mm/swap_prefetch.c~swap-prefetch-avoid-repeating-entry
+++ a/mm/swap_prefetch.c
@@ -515,6 +515,10 @@ static int kprefetchd(void *__unused)
 	/* Set ioprio to lowest if supported by i/o scheduler */
 	sys_ioprio_set(IOPRIO_WHO_PROCESS, 0, IOPRIO_CLASS_IDLE);
 
+	/* kprefetchd has nothing to do until it is woken up the first time */
+	set_current_state(TASK_INTERRUPTIBLE);
+	schedule();
+
 	do {
 		try_to_freeze();
 
_