X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=include%2Fwrapper%2Fwriteback.h;h=0aa69486d6fde4c6234b76c98da087d194d38eca;hb=2af7b13b53e4b92d3e76b74e5f1a7e0c26e58e9c;hp=e5f36c258534a211ba76d8b3a316c2dc4bdb3ce1;hpb=117ab60f69a98dcbc365de8008ab93e6699d153a;p=lttng-modules.git

diff --git a/include/wrapper/writeback.h b/include/wrapper/writeback.h
index e5f36c25..0aa69486 100644
--- a/include/wrapper/writeback.h
+++ b/include/wrapper/writeback.h
@@ -37,7 +37,21 @@ unsigned long wrapper_global_dirty_limit(void)
 		return 0;
 	}
 }
-#else
+
+/*
+ * Canary function to check for 'global_wb_domain' at compile time.
+ *
+ * From 'include/linux/writeback.h':
+ *
+ *   extern struct wb_domain global_wb_domain;
+ */
+static inline
+unsigned long __canary__global_wb_domain(void)
+{
+	return global_wb_domain.dirty_limit;
+}
+
+#elif LINUX_VERSION_CODE >= KERNEL_VERSION(3,1,0)
 
 static unsigned long *global_dirty_limit_sym;
 
@@ -54,17 +68,33 @@ unsigned long wrapper_global_dirty_limit(void)
 		return 0;
 	}
 }
+
+/*
+ * Canary function to check for 'global_dirty_limit' at compile time.
+ *
+ * From 'include/linux/writeback.h':
+ *
+ *   extern unsigned long global_dirty_limit;
+ */
+static inline
+unsigned long __canary__global_dirty_limit(void)
+{
+	return global_dirty_limit;
+}
+
 #endif
 
 #else /* CONFIG_KALLSYMS_ALL */
 
 #include <linux/writeback.h>
 
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3,1,0)
 static inline
 unsigned long wrapper_global_dirty_limit(void)
 {
 	return global_dirty_limit;
 }
+#endif
 
 #endif