diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c
index d559af9..35abcb8 100644
--- a/arch/x86/kernel/setup_percpu.c
+++ b/arch/x86/kernel/setup_percpu.c
@@ -1,3 +1,5 @@
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/init.h>
@@ -20,9 +22,9 @@
 #include <asm/stackprotector.h>
 
 #ifdef CONFIG_DEBUG_PER_CPU_MAPS
-# define DBG(x...) printk(KERN_DEBUG x)
+# define DBG(fmt, ...) pr_dbg(fmt, ##__VA_ARGS__)
 #else
-# define DBG(x...)
+# define DBG(fmt, ...) do { if (0) pr_dbg(fmt, ##__VA_ARGS__); } while (0)
 #endif
 
 DEFINE_PER_CPU(int, cpu_number);
@@ -116,8 +118,8 @@
 	} else {
 		ptr = __alloc_bootmem_node_nopanic(NODE_DATA(node),
 						   size, align, goal);
-		pr_debug("per cpu data for cpu%d %lu bytes on node%d at "
-			 "%016lx\n", cpu, size, node, __pa(ptr));
+		pr_debug("per cpu data for cpu%d %lu bytes on node%d at %016lx\n",
+			 cpu, size, node, __pa(ptr));
 	}
 	return ptr;
 #else
@@ -198,8 +200,7 @@
 					    pcpu_cpu_distance,
 					    pcpu_fc_alloc, pcpu_fc_free);
 		if (rc < 0)
-			pr_warning("PERCPU: %s allocator failed (%d), "
-				   "falling back to page size\n",
+			pr_warning("%s allocator failed (%d), falling back to page size\n",
 				   pcpu_fc_names[pcpu_chosen_fc], rc);
 	}
 	if (rc < 0)