mm: introduce debug_kmap_atomic
[linux-2.6.git] / mm / highmem.c
index 9101980..68eb1d9 100644 (file)
@@ -422,3 +422,48 @@ void __init page_address_init(void)
 }
 
 #endif /* defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL) */
+
+#if defined(CONFIG_DEBUG_HIGHMEM) && defined(CONFIG_TRACE_IRQFLAGS_SUPPORT)
+
+void debug_kmap_atomic(enum km_type type)
+{
+       static unsigned warn_count = 10;
+
+       if (unlikely(warn_count == 0))
+               return;
+
+       if (unlikely(in_interrupt())) {
+               if (in_irq()) {
+                       if (type != KM_IRQ0 && type != KM_IRQ1 &&
+                           type != KM_BIO_SRC_IRQ && type != KM_BIO_DST_IRQ &&
+                           type != KM_BOUNCE_READ) {
+                               WARN_ON(1);
+                               warn_count--;
+                       }
+               } else if (!irqs_disabled()) {  /* softirq */
+                       if (type != KM_IRQ0 && type != KM_IRQ1 &&
+                           type != KM_SOFTIRQ0 && type != KM_SOFTIRQ1 &&
+                           type != KM_SKB_SUNRPC_DATA &&
+                           type != KM_SKB_DATA_SOFTIRQ &&
+                           type != KM_BOUNCE_READ) {
+                               WARN_ON(1);
+                               warn_count--;
+                       }
+               }
+       }
+
+       if (type == KM_IRQ0 || type == KM_IRQ1 || type == KM_BOUNCE_READ ||
+                       type == KM_BIO_SRC_IRQ || type == KM_BIO_DST_IRQ) {
+               if (!irqs_disabled()) {
+                       WARN_ON(1);
+                       warn_count--;
+               }
+       } else if (type == KM_SOFTIRQ0 || type == KM_SOFTIRQ1) {
+               if (irq_count() == 0 && !irqs_disabled()) {
+                       WARN_ON(1);
+                       warn_count--;
+               }
+       }
+}
+
+#endif