+
+
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(4,2,0)
+
+static struct wb_domain *global_wb_domain_sym;
+
+static inline
+unsigned long wrapper_global_dirty_limit(void)
+{
+ if (!global_wb_domain_sym)
+ global_wb_domain_sym =
+ (void *) kallsyms_lookup_dataptr("global_wb_domain");
+ if (global_wb_domain_sym) {
+ return global_wb_domain_sym->dirty_limit;
+ } else {
+ printk_once(KERN_WARNING "LTTng: global_wb_domain symbol lookup failed.\n");
+ return 0;
+ }
+}
+
+/*
+ * 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)
+