[PATCH] sched: add debugging
These conditions should now be impossible, and we need to fix them if they
happen.
Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/kernel/sched.c b/kernel/sched.c
index 41e69b5..8b035a8 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -1942,15 +1942,7 @@
goto out_balanced;
}
- /*
- * This should be "impossible", but since load
- * balancing is inherently racy and statistical,
- * it could happen in theory.
- */
- if (unlikely(busiest == this_rq)) {
- WARN_ON(1);
- goto out_balanced;
- }
+ BUG_ON(busiest == this_rq);
schedstat_add(sd, lb_imbalance[idle], imbalance);
@@ -2052,11 +2044,13 @@
}
busiest = find_busiest_queue(group);
- if (!busiest || busiest == this_rq) {
+ if (!busiest) {
schedstat_inc(sd, lb_nobusyq[NEWLY_IDLE]);
goto out_balanced;
}
+ BUG_ON(busiest == this_rq);
+
/* Attempt to move tasks */
double_lock_balance(this_rq, busiest);