+static void show(char * str)
+{
+ int cpu = smp_processor_id();
+
+ printk(KERN_INFO "\n%s, CPU %d:\n", str, cpu);
+}
+
+#define MAXCOUNT 100000000
+
+static inline void wait_on_bh(void)
+{
+ int count = MAXCOUNT;
+ do {
+ if (!--count) {
+ show("wait_on_bh");
+ count = ~0;
+ }
+ /* nothing .. wait for the other bh's to go away */
+ } while (atomic_read(&global_bh_count) != 0);
+}
+
+/*
+ * This is called when we want to synchronize with
+ * bottom half handlers. We need to wait until
+ * no other CPU is executing any bottom half handler.
+ *
+ * Don't wait if we're already running in an interrupt
+ * context or are inside a bh handler.
+ */
+void synchronize_bh(void)
+{
+ if (atomic_read(&global_bh_count) && !in_interrupt())
+ wait_on_bh();
+}
+