2002-09-20 20:00:18

by Robert Love

[permalink] [raw]
Subject: [PATCH] schedule() in_atomic() check

Linus,

Resend of patch to make the in_atomic() check in schedule() actually
work. You merged the PREEMPT_ACTIVE bits, we just need to handle the
exit() case correctly.

Tested with and without CONFIG_PREEMPT -- works like a charm.

Patch is against current BK.

Robert Love

diff -urN linux-2.5.37/kernel/sched.c linux/kernel/sched.c
--- linux-2.5.37/kernel/sched.c Fri Sep 20 11:20:32 2002
+++ linux/kernel/sched.c Fri Sep 20 15:49:05 2002
@@ -940,8 +940,17 @@
struct list_head *queue;
int idx;

- if (unlikely(in_atomic()))
- BUG();
+ /*
+ * Test if we are atomic. Since do_exit() needs to call into
+ * schedule() atomically, we ignore that path for now.
+ * Otherwise, whine if we are scheduling when we should not be.
+ */
+ if (likely(current->state != TASK_ZOMBIE)) {
+ if (unlikely(in_atomic())) {
+ printk(KERN_ERR "bad: scheduling while atomic!\n");
+ dump_stack();
+ }
+ }

#if CONFIG_DEBUG_HIGHMEM
check_highmem_ptes();